Commit graph

630 commits

Author SHA1 Message Date
Linus Torvalds
505d195b0f Char/Misc/IIO driver changes for 7.0-rc1
Here is the big set of char/misc/iio and other smaller driver subsystem
 changes for 7.0-rc1.  Lots of little things in here, including:
   - Loads of iio driver changes and updates and additions
   - gpib driver updates
   - interconnect driver updates
   - i3c driver updates
   - hwtracing (coresight and intel) driver updates
   - deletion of the obsolete mwave driver
   - binder driver updates (rust and c versions)
   - mhi driver updates (causing a merge conflict, see below)
   - mei driver updates
   - fsi driver updates
   - eeprom driver updates
   - lots of other small char and misc driver updates and cleanups
 
 All of these have been in linux-next for a while, with no reported
 issues except for a merge conflict with your tree due to the mhi driver
 changes in the drivers/net/wireless/ath/ath12k/mhi.c file.  To fix that
 up, just delete the "auto_queue" structure fields being set, see this
 message for the full change needed:
 	https://lore.kernel.org/r/aXD6X23btw8s-RZP@sirena.org.uk
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc/IIO driver updates from Greg KH:
 "Here is the big set of char/misc/iio and other smaller driver
  subsystem changes for 7.0-rc1. Lots of little things in here,
  including:

   - Loads of iio driver changes and updates and additions

   - gpib driver updates

   - interconnect driver updates

   - i3c driver updates

   - hwtracing (coresight and intel) driver updates

   - deletion of the obsolete mwave driver

   - binder driver updates (rust and c versions)

   - mhi driver updates (causing a merge conflict, see below)

   - mei driver updates

   - fsi driver updates

   - eeprom driver updates

   - lots of other small char and misc driver updates and cleanups

  All of these have been in linux-next for a while, with no reported
  issues"

* tag 'char-misc-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (297 commits)
  mux: mmio: fix regmap leak on probe failure
  rust_binder: return p from rust_binder_transaction_target_node()
  drivers: android: binder: Update ARef imports from sync::aref
  rust_binder: fix needless borrow in context.rs
  iio: magn: mmc5633: Fix Kconfig for combination of I3C as module and driver builtin
  iio: sca3000: Fix a resource leak in sca3000_probe()
  iio: proximity: rfd77402: Add interrupt handling support
  iio: proximity: rfd77402: Document device private data structure
  iio: proximity: rfd77402: Use devm-managed mutex initialization
  iio: proximity: rfd77402: Use kernel helper for result polling
  iio: proximity: rfd77402: Align polling timeout with datasheet
  iio: cros_ec: Allow enabling/disabling calibration mode
  iio: frequency: ad9523: correct kernel-doc bad line warning
  iio: buffer: buffer_impl.h: fix kernel-doc warnings
  iio: gyro: itg3200: Fix unchecked return value in read_raw
  MAINTAINERS: add entry for ADE9000 driver
  iio: accel: sca3000: remove unused last_timestamp field
  iio: accel: adxl372: remove unused int2_bitmask field
  iio: adc: ad7766: Use iio_trigger_generic_data_rdy_poll()
  iio: magnetometer: Remove IRQF_ONESHOT
  ...
2026-02-17 09:11:04 -08:00
Linus Torvalds
3c6e577d5a tracing updates for 7.0:
User visible changes:
 
 - Add an entry into MAINTAINERS file for RUST versions of code
 
   There's now RUST code for tracing and static branches. To differentiate
   that code from the C code, add entries in for the RUST version (with "[RUST]"
   around it) so that the right maintainers get notified on changes.
 
 - New bitmask-list option added to tracefs
 
   When this is set, bitmasks in trace event are not displayed as hex
   numbers, but instead as lists: e.g. 0-5,7,9 instead of 0000015f
 
 - New show_event_filters file in tracefs
 
   Instead of having to search all events/*/*/filter for any active filters
   enabled in the trace instance, the file show_event_filters will list them
   so that there's only one file that needs to be examined to see if any
   filters are active.
 
 - New show_event_triggers file in tracefs
 
   Instead of having to search all events/*/*/trigger for any active triggers
   enabled in the trace instance, the file show_event_triggers will list them
   so that there's only one file that needs to be examined to see if any
   triggers are active.
 
 - Have traceoff_on_warning disable trace pintk buffer too
 
   Recently recording of trace_printk() could go to other trace instances
   instead of the top level instance. But if traceoff_on_warning triggers, it
   doesn't stop the buffer with trace_printk() and that data can easily be
   lost by being overwritten. Have traceoff_on_warning also disable the
   instance that has trace_printk() being written to it.
 
 - Update the hist_debug file to show what function the field uses
 
   When CONFIG_HIST_TRIGGERS_DEBUG is enabled, a hist_debug file exists for
   every event. This displays the internal data of any histogram enabled for
   that event. But it is lacking the function that is called to process one
   of its fields. This is very useful information that was missing when
   debugging histograms.
 
 - Up the histogram stack size from 16 to 31
 
   Stack traces can be used as keys for event histograms. Currently the size
   of the stack that is stored is limited to just 16 entries. But the storage
   space in the histogram is 256 bytes, meaning that it can store up to 31
   entries (plus one for the count of entries). Instead of letting that space
   go to waste, up the limit from 16 to 31. This makes the keys much more
   useful.
 
 - Fix permissions of per CPU file buffer_size_kb
 
   The per CPU file of buffer_size_kb was incorrectly set to read only in a
   previous cleanup. It should be writable.
 
 - Reset "last_boot_info" if the persistent buffer is cleared
 
   The last_boot_info shows address information of a persistent ring buffer
   if it contains data from a previous boot. It is cleared when recording
   starts again, but it is not cleared when the buffer is reset. The data is
   useless after a reset so clear it on reset too.
 
 Internal changes:
 
 - A change was made to allow tracepoint callbacks to have preemption
   enabled, and instead be protected by SRCU. This required some updates to
   the callbacks for perf and BPF.
 
   perf needed to disable preemption directly in its callback because it
   expects preemption disabled in the later code.
 
   BPF needed to disable migration, as its code expects to run completely on
   the same CPU.
 
 - Have irq_work wake up other CPU if current CPU is "isolated"
 
   When there's a waiter waiting on ring buffer data and a new event happens,
   an irq work is triggered to wake up that waiter. This is noisy on isolated
   CPUs (running NO_HZ_FULL). Trigger an IPI to a house keeping CPU instead.
 
 - Use proper free of trigger_data instead of open coding it in.
 
 - Remove redundant call of event_trigger_reset_filter()
 
   It was called immediately in a function that was called right after it.
 
 - Workqueue cleanups
 
 - Report errors if tracing_update_buffers() were to fail.
 
 - Make the enum update workqueue generic for other parts of tracing
 
   On boot up, a work queue is created to convert enum names into their
   numbers in the trace event format files. This work queue can also be used
   for other aspects of tracing that takes some time and shouldn't be called
   by the init call code.
 
   The blk_trace initialization takes a bit of time. Have the initialization
   code moved to the new tracing generic work queue function.
 
 - Skip kprobe boot event creation call if there's no kprobes defined on cmdline
 
   The kprobe initialization to set up kprobes if they are defined on the
   cmdline requires taking the event_mutex lock. This can be held by other
   tracing code doing initialization for a long time. Since kprobes added to
   the kernel command line need to be setup immediately, as they may be
   tracing early initialization code, they cannot be postponed in a work
   queue and must be setup in the initcall code.
 
   If there's no kprobe on the kernel cmdline, there's no reason to take the
   mutex and slow down the boot up code waiting to get the lock only to find
   out there's nothing to do. Simply exit out early if there's no kprobes on
   the kernel cmdline.
 
   If there are kprobes on the cmdline, then someone cares more about tracing
   over the speed of boot up.
 
 - Clean up the trigger code a bit
 
 - Move code out of trace.c and into their own files
 
   trace.c is now over 11,000 lines of code and has become more difficult to
   maintain. Start splitting it up so that related code is in their own
   files.
 
   Move all the trace_printk() related code into trace_printk.c.
 
   Move the __always_inline stack functions into trace.h.
 
   Move the pid filtering code into a new trace_pid.c file.
 
 - Better define the max latency and snapshot code
 
   The latency tracers have a "max latency" buffer that is a copy of the main
   buffer and gets swapped with it when a new high latency is detected. This
   keeps the trace up to the highest latency around where this max_latency
   buffer is never written to. It is only used to save the last max latency
   trace.
 
   A while ago a snapshot feature was added to tracefs to allow user space to
   perform the same logic. It could also enable events to trigger a
   "snapshot" if one of their fields hit a new high. This was built on top of
   the latency max_latency buffer logic.
 
   Because snapshots came later, they were dependent on the latency tracers
   to be enabled. In reality, the latency tracers depend on the snapshot code
   and not the other way around. It was just that they came first.
 
   Restructure the code and the kconfigs to have the latency tracers depend
   on snapshot code instead. This actually simplifies the logic a bit and
   allows to disable more when the latency tracers are not defined and the
   snapshot code is.
 
 - Fix a "false sharing" in the hwlat tracer code
 
   The loop to search for latency in hardware was using a variable that could
   be changed by user space for each sample. If the user change this
   variable, it could cause a bus contention, and reading that variable can
   show up as a large latency in the trace causing a false positive. Read
   this variable at the start of the sample with a READ_ONCE() into a local
   variable and keep the code from sharing cache lines with readers.
 
 - Fix function graph tracer static branch optimization code
 
   When only one tracer is defined for function graph tracing, it uses a
   static branch to call that tracer directly. When another tracer is added,
   it goes into loop logic to call all the registered callbacks.
 
   The code was incorrect when going back to one tracer and never re-enabled
   the static branch again to do the optimization code.
 
 - And other small fixes and cleanups.
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Merge tag 'trace-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:
 "User visible changes:

   - Add an entry into MAINTAINERS file for RUST versions of code

     There's now RUST code for tracing and static branches. To
     differentiate that code from the C code, add entries in for the
     RUST version (with "[RUST]" around it) so that the right
     maintainers get notified on changes.

   - New bitmask-list option added to tracefs

     When this is set, bitmasks in trace event are not displayed as hex
     numbers, but instead as lists: e.g. 0-5,7,9 instead of 0000015f

   - New show_event_filters file in tracefs

     Instead of having to search all events/*/*/filter for any active
     filters enabled in the trace instance, the file show_event_filters
     will list them so that there's only one file that needs to be
     examined to see if any filters are active.

   - New show_event_triggers file in tracefs

     Instead of having to search all events/*/*/trigger for any active
     triggers enabled in the trace instance, the file
     show_event_triggers will list them so that there's only one file
     that needs to be examined to see if any triggers are active.

   - Have traceoff_on_warning disable trace pintk buffer too

     Recently recording of trace_printk() could go to other trace
     instances instead of the top level instance. But if
     traceoff_on_warning triggers, it doesn't stop the buffer with
     trace_printk() and that data can easily be lost by being
     overwritten. Have traceoff_on_warning also disable the instance
     that has trace_printk() being written to it.

   - Update the hist_debug file to show what function the field uses

     When CONFIG_HIST_TRIGGERS_DEBUG is enabled, a hist_debug file
     exists for every event. This displays the internal data of any
     histogram enabled for that event. But it is lacking the function
     that is called to process one of its fields. This is very useful
     information that was missing when debugging histograms.

   - Up the histogram stack size from 16 to 31

     Stack traces can be used as keys for event histograms. Currently
     the size of the stack that is stored is limited to just 16 entries.
     But the storage space in the histogram is 256 bytes, meaning that
     it can store up to 31 entries (plus one for the count of entries).
     Instead of letting that space go to waste, up the limit from 16 to
     31. This makes the keys much more useful.

   - Fix permissions of per CPU file buffer_size_kb

     The per CPU file of buffer_size_kb was incorrectly set to read only
     in a previous cleanup. It should be writable.

   - Reset "last_boot_info" if the persistent buffer is cleared

     The last_boot_info shows address information of a persistent ring
     buffer if it contains data from a previous boot. It is cleared when
     recording starts again, but it is not cleared when the buffer is
     reset. The data is useless after a reset so clear it on reset too.

  Internal changes:

   - A change was made to allow tracepoint callbacks to have preemption
     enabled, and instead be protected by SRCU. This required some
     updates to the callbacks for perf and BPF.

     perf needed to disable preemption directly in its callback because
     it expects preemption disabled in the later code.

     BPF needed to disable migration, as its code expects to run
     completely on the same CPU.

   - Have irq_work wake up other CPU if current CPU is "isolated"

     When there's a waiter waiting on ring buffer data and a new event
     happens, an irq work is triggered to wake up that waiter. This is
     noisy on isolated CPUs (running NO_HZ_FULL). Trigger an IPI to a
     house keeping CPU instead.

   - Use proper free of trigger_data instead of open coding it in.

   - Remove redundant call of event_trigger_reset_filter()

     It was called immediately in a function that was called right after
     it.

   - Workqueue cleanups

   - Report errors if tracing_update_buffers() were to fail.

   - Make the enum update workqueue generic for other parts of tracing

     On boot up, a work queue is created to convert enum names into
     their numbers in the trace event format files. This work queue can
     also be used for other aspects of tracing that takes some time and
     shouldn't be called by the init call code.

     The blk_trace initialization takes a bit of time. Have the
     initialization code moved to the new tracing generic work queue
     function.

   - Skip kprobe boot event creation call if there's no kprobes defined
     on cmdline

     The kprobe initialization to set up kprobes if they are defined on
     the cmdline requires taking the event_mutex lock. This can be held
     by other tracing code doing initialization for a long time. Since
     kprobes added to the kernel command line need to be setup
     immediately, as they may be tracing early initialization code, they
     cannot be postponed in a work queue and must be setup in the
     initcall code.

     If there's no kprobe on the kernel cmdline, there's no reason to
     take the mutex and slow down the boot up code waiting to get the
     lock only to find out there's nothing to do. Simply exit out early
     if there's no kprobes on the kernel cmdline.

     If there are kprobes on the cmdline, then someone cares more about
     tracing over the speed of boot up.

   - Clean up the trigger code a bit

   - Move code out of trace.c and into their own files

     trace.c is now over 11,000 lines of code and has become more
     difficult to maintain. Start splitting it up so that related code
     is in their own files.

     Move all the trace_printk() related code into trace_printk.c.

     Move the __always_inline stack functions into trace.h.

     Move the pid filtering code into a new trace_pid.c file.

   - Better define the max latency and snapshot code

     The latency tracers have a "max latency" buffer that is a copy of
     the main buffer and gets swapped with it when a new high latency is
     detected. This keeps the trace up to the highest latency around
     where this max_latency buffer is never written to. It is only used
     to save the last max latency trace.

     A while ago a snapshot feature was added to tracefs to allow user
     space to perform the same logic. It could also enable events to
     trigger a "snapshot" if one of their fields hit a new high. This
     was built on top of the latency max_latency buffer logic.

     Because snapshots came later, they were dependent on the latency
     tracers to be enabled. In reality, the latency tracers depend on
     the snapshot code and not the other way around. It was just that
     they came first.

     Restructure the code and the kconfigs to have the latency tracers
     depend on snapshot code instead. This actually simplifies the logic
     a bit and allows to disable more when the latency tracers are not
     defined and the snapshot code is.

   - Fix a "false sharing" in the hwlat tracer code

     The loop to search for latency in hardware was using a variable
     that could be changed by user space for each sample. If the user
     change this variable, it could cause a bus contention, and reading
     that variable can show up as a large latency in the trace causing a
     false positive. Read this variable at the start of the sample with
     a READ_ONCE() into a local variable and keep the code from sharing
     cache lines with readers.

   - Fix function graph tracer static branch optimization code

     When only one tracer is defined for function graph tracing, it uses
     a static branch to call that tracer directly. When another tracer
     is added, it goes into loop logic to call all the registered
     callbacks.

     The code was incorrect when going back to one tracer and never
     re-enabled the static branch again to do the optimization code.

   - And other small fixes and cleanups"

* tag 'trace-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (46 commits)
  function_graph: Restore direct mode when callbacks drop to one
  tracing: Fix indentation of return statement in print_trace_fmt()
  tracing: Reset last_boot_info if ring buffer is reset
  tracing: Fix to set write permission to per-cpu buffer_size_kb
  tracing: Fix false sharing in hwlat get_sample()
  tracing: Move d_max_latency out of CONFIG_FSNOTIFY protection
  tracing: Better separate SNAPSHOT and MAX_TRACE options
  tracing: Add tracer_uses_snapshot() helper to remove #ifdefs
  tracing: Rename trace_array field max_buffer to snapshot_buffer
  tracing: Move pid filtering into trace_pid.c
  tracing: Move trace_printk functions out of trace.c and into trace_printk.c
  tracing: Use system_state in trace_printk_init_buffers()
  tracing: Have trace_printk functions use flags instead of using global_trace
  tracing: Make tracing_update_buffers() take NULL for global_trace
  tracing: Make printk_trace global for tracing system
  tracing: Move ftrace_trace_stack() out of trace.c and into trace.h
  tracing: Move __trace_buffer_{un}lock_*() functions to trace.h
  tracing: Make tracing_selftest_running global to the tracing subsystem
  tracing: Make tracing_disabled global for tracing system
  tracing: Clean up use of trace_create_maxlat_file()
  ...
2026-02-13 19:25:16 -08:00
Linus Torvalds
f75c03a761 runtime verifier changes for 7.0:
- Refactor da_monitor to minimise macros
 
   Complete refactor of da_monitor.h to reduce reliance on macros
   generating functions. Use generic static functions and uses the
   preprocessor only when strictly necessary (e.g. for tracepoint
   handlers).
 
   The change essentially relies on functions with generic names (e.g.
   da_handle) instead of monitor-specific as well adding the need to
   define constant (e.g. MONITOR_NAME, MONITOR_TYPE) before including the
   header rather than calling macros that would define functions.
   Also adapt monitors and documentation accordingly.
 
 - Cleanup DA code generation scripts
 
   Clean up functions in dot2c removing reimplementations of trivial
   library functions (__buff_to_string) and removing some other unused
   intermediate steps.
 
 - Annotate functions with types in the rvgen python scripts
 
 - Remove superfluous assignments and cleanup generated code
 
   The rvgen scripts generate a superfluous assignment to 0 for enum
   variables and don't add commas to the last elements, which is against
   the kernel coding standards. Change the generation process for a
   better compliance and slightly simpler logic.
 
 - Remove superfluous declarations from generated code
 
   The monitor container source files contained a declaration and a
   definition for the rv_monitor variable. The former is superfluous and
   was removed.
 
 - Fix reference to outdated documentation
 
   s/da_monitor_synthesis.rst/monitor_synthesis.rst in comment in
   da_monitor.h
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Merge tag 'trace-rv-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull runtime verifier updates from Steven Rostedt:

 - Refactor da_monitor to minimize macros

   Complete refactor of da_monitor.h to reduce reliance on macros
   generating functions. Use generic static functions and uses the
   preprocessor only when strictly necessary (e.g. for tracepoint
   handlers).

   The change essentially relies on functions with generic names (e.g.
   da_handle) instead of monitor-specific as well adding the need to
   define constant (e.g. MONITOR_NAME, MONITOR_TYPE) before including
   the header rather than calling macros that would define functions.
   Also adapt monitors and documentation accordingly.

 - Cleanup DA code generation scripts

   Clean up functions in dot2c removing reimplementations of trivial
   library functions (__buff_to_string) and removing some other unused
   intermediate steps.

 - Annotate functions with types in the rvgen python scripts

 - Remove superfluous assignments and cleanup generated code

   The rvgen scripts generate a superfluous assignment to 0 for enum
   variables and don't add commas to the last elements, which is against
   the kernel coding standards. Change the generation process for a
   better compliance and slightly simpler logic.

 - Remove superfluous declarations from generated code

   The monitor container source files contained a declaration and a
   definition for the rv_monitor variable. The former is superfluous and
   was removed.

 - Fix reference to outdated documentation

   s/da_monitor_synthesis.rst/monitor_synthesis.rst in comment in
   da_monitor.h

* tag 'trace-rv-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  rv: Fix documentation reference in da_monitor.h
  verification/rvgen: Remove unused variable declaration from containers
  verification/dot2c: Remove superfluous enum assignment and add last comma
  verification/dot2c: Remove __buff_to_string() and cleanup
  verification/rvgen: Annotate DA functions with types
  verification/rvgen: Adapt dot2k and templates after refactoring da_monitor.h
  Documentation/rv: Adapt documentation after da_monitor refactoring
  rv: Cleanup da_monitor after refactor
  rv: Refactor da_monitor to minimise macros
2026-02-12 14:08:49 -08:00
Linus Torvalds
1c2b4a4c2b pci-v7.0-changes
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Merge tag 'pci-v7.0-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:

   - Don't try to enable Extended Tags on VFs since that bit is Reserved
     and causes misleading log messages (Håkon Bugge)

   - Initialize Endpoint Read Completion Boundary to match Root Port,
     regardless of ACPI _HPX (Håkon Bugge)

   - Apply _HPX PCIe Setting Record only to AER configuration, and only
     when OS owns PCIe hotplug but not AER, to avoid clobbering Extended
     Tag and Relaxed Ordering settings (Håkon Bugge)

  Resource management:

   - Move CardBus code to setup-cardbus.c and only build it when
     CONFIG_CARDBUS is set (Ilpo Järvinen)

   - Fix bridge window alignment with optional resources, where
     additional alignment requirement was previously lost (Ilpo
     Järvinen)

   - Stop over-estimating bridge window size since they are now assigned
     without any gaps between them (Ilpo Järvinen)

   - Increase resource MAX_IORES_LEVEL to avoid /proc/iomem flattening
     for nested bridges and endpoints (Ilpo Järvinen)

   - Add pbus_mem_size_optional() to handle sizes of optional resources
     (SR-IOV VF BARs, expansion ROMs, bridge windows) (Ilpo Järvinen)

   - Don't claim disabled bridge windows to avoid spurious claim
     failures (Ilpo Järvinen)

  Driver binding:

   - Fix device reference leak in pcie_port_remove_service() (Uwe
     Kleine-König)

   - Move pcie_port_bus_match() and pcie_port_bus_type to PCIe-specific
     portdrv.c (Uwe Kleine-König)

   - Convert portdrv to use pcie_port_bus_type.probe() and .remove()
     callbacks so .probe() and .remove() can eventually be removed from
     struct device_driver (Uwe Kleine-König)

  Error handling:

   - Clear stale errors on reporting agents upon probe so they don't
     look like recent errors (Lukas Wunner)

   - Add generic RAS tracepoint for hotplug events (Shuai Xue)

   - Add RAS tracepoint for link speed changes (Shuai Xue)

  Power management:

   - Avoid redundant delay on transition from D3hot to D3cold if the
     device was already in D3hot (Brian Norris)

   - Prevent runtime suspend until devices are fully initialized to
     avoid saving incompletely configured device state (Brian Norris)

  Power control:

   - Add power_on/off callbacks with generic signature to pwrseq,
     tc9563, and slot drivers so they can be used by pwrctrl core
     (Manivannan Sadhasivam)

   - Add PCIe M.2 connector support to the slot pwrctrl driver
     (Manivannan Sadhasivam)

   - Switch to pwrctrl interfaces to create, destroy, and power on/off
     devices, calling them from host controller drivers instead of the
     PCI core (Manivannan Sadhasivam)

   - Drop qcom .assert_perst() callbacks since this is now done by the
     controller driver instead of the pwrctrl driver (Manivannan
     Sadhasivam)

  Virtualization:

   - Remove an incorrect unlock in pci_slot_trylock() error handling
     (Jinhui Guo)

   - Lock the bridge device for slot reset (Keith Busch)

   - Enable ACS after IOMMU configuration on OF platforms so ACS is
     enabled an all devices; previously the first device enumerated
     (typically a Root Port) didn't have ACS enabled (Manivannan
     Sadhasivam)

   - Disable ACS Source Validation for IDT 0x80b5 and 0x8090 switches to
     work around hardware erratum; previously ACS SV was only
     temporarily disabled, which worked for enumeration but not after
     reset (Manivannan Sadhasivam)

  Peer-to-peer DMA:

   - Release per-CPU pgmap ref when vm_insert_page() fails to avoid hang
     when removing the PCI device (Hou Tao)

   - Remove incorrect p2pmem_alloc_mmap() warning about page refcount
     (Hou Tao)

  Endpoint framework:

   - Add configfs sub-groups synchronously to avoid NULL pointer
     dereference when racing with removal (Liu Song)

   - Fix swapped parameters in pci_{primary/secondary}_epc_epf_unlink()
     functions (Manikanta Maddireddy)

  ASPEED PCIe controller driver:

   - Add ASPEED Root Complex DT binding and driver (Jacky Chou)

  Freescale i.MX6 PCIe controller driver:

   - Add DT binding and driver support for an optional external refclock
     in addition to the refclock from the internal PLL (Richard Zhu)

   - Fix CLKREQ# control so host asserts it during enumeration and
     Endpoints can use it afterwards to exit the L1.2 link state
     (Richard Zhu)

  NVIDIA Tegra PCIe controller driver:

   - Export irq_domain_free_irqs() to allow PCI/MSI drivers that tear
     down MSI domains to be built as modules (Aaron Kling)

   - Allow pci-tegra to be built as a module (Aaron Kling)

  NVIDIA Tegra194 PCIe controller driver:

   - Relax Kconfig so tegra194 can be built for platforms beyond
     Tegra194 (Vidya Sagar)

  Qualcomm PCIe controller driver:

   - Merge SC8180x DT binding into SM8150 (Krzysztof Kozlowski)

   - Move SDX55, SDM845, QCS404, IPQ5018, IPQ6018, IPQ8074 Gen3,
     IPQ8074, IPQ4019, IPQ9574, APQ8064, MSM8996, APQ8084 to dedicated
     schema (Krzysztof Kozlowski)

   - Add DT binding and driver support for SA8255p Endpoint being
     configured by firmware (Mrinmay Sarkar)

   - Parse PERST# from all PCIe bridge nodes for future platforms that
     will have PERST# in Switch Downstream Ports as well as in Root
     Ports (Manivannan Sadhasivam)

  Renesas RZ/G3S PCIe controller driver:

   - Use pci_generic_config_write() since the writability provided by
     the custom wrapper is unnecessary (Claudiu Beznea)

  SOPHGO PCIe controller driver:

   - Disable ASPM L0s and L1 on Sophgo 2044 PCIe Root Ports (Inochi
     Amaoto)

  Synopsys DesignWare PCIe controller driver:

   - Extend PCI_FIND_NEXT_CAP() and PCI_FIND_NEXT_EXT_CAP() to return a
     pointer to the preceding Capability, to allow removal of
     Capabilities that are advertised but not fully implemented (Qiang
     Yu)

   - Remove MSI and MSI-X Capabilities in platforms that can't support
     them, so the PCI core automatically falls back to INTx (Qiang Yu)

   - Add ASPM L1.1 and L1.2 Substates context to debugfs ltssm_status
     for drivers that support this (Shawn Lin)

   - Skip PME_Turn_Off broadcast and L2/L3 transition during suspend if
     link is not up to avoid an unnecessary timeout (Manivannan
     Sadhasivam)

   - Revert dw-rockchip, qcom, and DWC core changes that used link-up
     IRQs to trigger enumeration instead of waiting for link to be up
     because the PCI core doesn't allocate bus number space for
     hierarchies that might be attached (Niklas Cassel)

   - Make endpoint iATU entry for MSI permanent instead of programming
     it dynamically, which is slow and racy with respect to other
     concurrent traffic, e.g., eDMA (Koichiro Den)

   - Use iMSI-RX MSI target address when possible to fix endpoints using
     32-bit MSI (Shawn Lin)

   - Allow DWC host controller driver probe to continue if device is not
     found or found but inactive; only fail when there's an error with
     the link (Manivannan Sadhasivam)

   - For controllers like NXP i.MX6QP and i.MX7D, where LTSSM registers
     are not accessible after PME_Turn_Off, simply wait 10ms instead of
     polling for L2/L3 Ready (Richard Zhu)

   - Use multiple iATU entries to map large bridge windows and DMA
     ranges when necessary instead of failing (Samuel Holland)

   - Add EPC dynamic_inbound_mapping feature bit for Endpoint
     Controllers that can update BAR inbound address translation without
     requiring EPF driver to clear/reset the BAR first, and advertise it
     for DWC-based Endpoints (Koichiro Den)

   - Add EPC subrange_mapping feature bit for Endpoint Controllers that
     can map multiple independent inbound regions in a single BAR,
     implement subrange mapping, advertise it for DWC-based Endpoints,
     and add Endpoint selftests for it (Koichiro Den)

   - Make resizable BARs work for Endpoint multi-PF configurations;
     previously it only worked for PF 0 (Aksh Garg)

   - Fix Endpoint non-PF 0 support for BAR configuration, ATU mappings,
     and Address Match Mode (Aksh Garg)

   - Set up iATU when ECAM is enabled; previously IO and MEM outbound
     windows weren't programmed, and ECAM-related iATU entries weren't
     restored after suspend/resume, so config accesses failed (Krishna
     Chaitanya Chundru)

  Miscellaneous:

   - Use system_percpu_wq and WQ_PERCPU to explicitly request per-CPU
     work so WQ_UNBOUND can eventually be removed (Marco Crivellari)"

* tag 'pci-v7.0-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (176 commits)
  PCI/bwctrl: Disable BW controller on Intel P45 using a quirk
  PCI: Disable ACS SV for IDT 0x8090 switch
  PCI: Disable ACS SV for IDT 0x80b5 switch
  PCI: Cache ACS Capabilities register
  PCI: Enable ACS after configuring IOMMU for OF platforms
  PCI: Add ACS quirk for Pericom PI7C9X2G404 switches [12d8:b404]
  PCI: Add ACS quirk for Qualcomm Hamoa & Glymur
  PCI: Use device_lock_assert() to verify device lock is held
  PCI: Use lockdep_assert_held(pci_bus_sem) to verify lock is held
  PCI: Fix pci_slot_lock () device locking
  PCI: Fix pci_slot_trylock() error handling
  PCI: Mark Nvidia GB10 to avoid bus reset
  PCI: Mark ASM1164 SATA controller to avoid bus reset
  PCI: host-generic: Avoid reporting incorrect 'missing reg property' error
  PCI/PME: Replace RMW of Root Status register with direct write
  PCI/AER: Clear stale errors on reporting agents upon probe
  PCI: Don't claim disabled bridge windows
  PCI: rzg3s-host: Fix device node reference leak in rzg3s_pcie_host_parse_port()
  PCI: dwc: Fix missing iATU setup when ECAM is enabled
  PCI: dwc: Clean up iATU index usage in dw_pcie_iatu_setup()
  ...
2026-02-11 17:20:38 -08:00
Aaron Tomlin
6a80838814 tracing: Add show_event_triggers to expose active event triggers
To audit active event triggers, userspace currently must traverse the
events/ directory and read each individual trigger file. This is
cumbersome for system-wide auditing or debugging.

Introduce "show_event_triggers" at the trace root directory. This file
displays all events that currently have one or more triggers applied,
alongside the trigger configuration, in a consolidated
system:event [tab] trigger format.

The implementation leverages the existing trace_event_file iterators
and uses the trigger's own print() operation to ensure output
consistency with the per-event trigger files.

Link: https://patch.msgid.link/20260105142939.2655342-3-atomlin@atomlin.com
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-01-26 17:44:24 -05:00
Aaron Tomlin
729757b96a tracing: Add show_event_filters to expose active event filters
Currently, to audit active Ftrace event filters, userspace must
recursively traverse the events/ directory and read each individual
filter file. This is inefficient for monitoring tools and debugging.

Introduce "show_event_filters" at the trace root directory. This file
displays all events that currently have a filter applied, alongside the
actual filter string, in a consolidated system:event [tab] filter
format.

The implementation reuses the existing trace_event_file iterators to
ensure atomic traversal of the event list and utilises guard(rcu)() for
automatic, scope-based protection when accessing volatile filter
strings.

Link: https://patch.msgid.link/20260105142939.2655342-2-atomlin@atomlin.com
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-01-26 17:44:15 -05:00
Aaron Tomlin
2cddfc2e8f tracing: Add bitmask-list option for human-readable bitmask display
Add support for displaying bitmasks in human-readable list format (e.g.,
0,2-5,7) in addition to the default hexadecimal bitmap representation.
This is particularly useful when tracing CPU masks and other large
bitmasks where individual bit positions are more meaningful than their
hexadecimal encoding.

When the "bitmask-list" option is enabled, the printk "%*pbl" format
specifier is used to render bitmasks as comma-separated ranges, making
trace output easier to interpret for complex CPU configurations and
large bitmask values.

Link: https://patch.msgid.link/20251226160724.2246493-2-atomlin@atomlin.com
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-01-26 17:00:50 -05:00
Jani Nikula
a592a36e49 Documentation: use a source-read extension for the index link boilerplate
The root document usually has a special :ref:`genindex` link to the
generated index. This is also the case for Documentation/index.rst. The
other index.rst files deeper in the directory hierarchy usually don't.

For SPHINXDIRS builds, the root document isn't Documentation/index.rst,
but some other index.rst in the hierarchy. Currently they have a
".. only::" block to add the index link when doing SPHINXDIRS html
builds.

This is obviously very tedious and repetitive. The link is also added to
all index.rst files in the hierarchy for SPHINXDIRS builds, not just the
root document.

Put the boilerplate in a sphinx-includes/subproject-index.rst file, and
include it at the end of the root document for subproject builds in an
ad-hoc source-read extension defined in conf.py.

For now, keep having the boilerplate in translations, because this
approach currently doesn't cover translated index link headers.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[jc: did s/doctree/kern_doc_dir/ ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
2026-01-23 11:59:34 -07:00
Petr Vorel
a02857e734 Documentation/trace: Fix links to other documents
Link to another document does not require 'file:'. Removing it fixes
links in generated html docs.

Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260111223643.174812-2-pvorel@suse.cz>
2026-01-12 09:31:19 -07:00
Gabriele Monaco
e4a1e415eb Documentation/rv: Adapt documentation after da_monitor refactoring
Previous changes refactored the da_monitor header file to avoid using
macros. This implies a few changes in how to import and use da_monitor
helpers:

 DECLARE_DA_MON_<TYPE>(name, type) is substituted by
 #define RV_MON_TYPE RV_MON_<TYPE>

 da_handle_event_<name>() is substituted by
 da_handle_event()

Update the documentation to reflect the changes.

Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://lore.kernel.org/r/20251126104241.291258-4-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-01-12 07:43:50 +01:00
Shuai Xue
8236fc613d Documentation: tracing: Add PCI tracepoint documentation
The PCI tracing system provides tracepoints to monitor critical hardware
events that can impact system performance and reliability. Add
documentation about it.

Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
[bhelgaas: squash fixes:
https://lore.kernel.org/r/20260108013956.14351-2-bagasdotme@gmail.com
https://lore.kernel.org/r/20260108013956.14351-3-bagasdotme@gmail.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://patch.msgid.link/20251210132907.58799-4-xueshuai@linux.alibaba.com
2026-01-08 10:06:19 -06:00
Soham Metha
7508b208f1 Documentation/rv: Fix dead link to monitor_synthesis.rst
The file 'da_monitor_synthesis.rst' was renamed to 'monitor_synthesis.rst' in
commit f40a7c0602
("Documentation/rv: Prepare monitor synthesis document for LTL inclusion").

Signed-off-by: Soham Metha <sohammetha01@gmail.com>
Fixes: f40a7c0602 ("Documentation/rv: Prepare monitor synthesis document for LTL inclusion")
Acked-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251204032452.9523-1-sohammetha01@gmail.com>
2025-12-22 15:30:26 -07:00
James Clark
19214ad0a4 coresight: docs: Document etm4x timestamp interval option
Document how the new field is used, maximum value and the interaction
with SYNC timestamps.

Tested-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20251128-james-cs-syncfreq-v8-13-4d319764cc58@linaro.org
2025-12-22 15:30:54 +00:00
Linus Torvalds
69c5079b49 tracing updates for v6.19:
- Merge branch shared with kprobes on extending trace options
 
   The trace options were defined by a 32 bit variable. This limits the
   tracing instances to have a total of 32 different options. As that limit
   has been hit, and more options are being added, increase the option mask
   to a 64 bit number, doubling the number of options available.
 
   As this is required for the kprobe topic branches as well as the tracing
   topic branch, a separate branch was created and merged into both.
 
 - Make trace_user_fault_read() available for the rest of tracing
 
   The function trace_user_fault_read() is used by trace_marker file read to
   allow reading user space to be done fast and without locking or
   allocations. Make this available so that the system call trace events can
   use it too.
 
 - Have system call trace events read user space values
 
   Now that the system call trace events callbacks are called in a faultable
   context, take advantage of this and read the user space buffers for
   various system calls. For example, show the path name of the openat system
   call instead of just showing the pointer to that path name in user space.
   Also show the contents of the buffer of the write system call. Several
   system call trace events are updated to make tracing into a light weight
   strace tool for all applications in the system.
 
 - Update perf system call tracing to do the same
 
 - And a config and syscall_user_buf_size file to control the size of the buffer
 
   Limit the amount of data that can be read from user space. The default
   size is 63 bytes but that can be expanded to 165 bytes.
 
 - Allow the persistent ring buffer to print system calls normally
 
   The persistent ring buffer prints trace events by their type and ignores
   the print_fmt. This is because the print_fmt may change from kernel to
   kernel. As the system call output is fixed by the system call ABI itself,
   there's no reason to limit that. This makes reading the system call events
   in the persistent ring buffer much nicer and easier to understand.
 
 - Add options to show text offset to function profiler
 
   The function profiler that counts the number of times a function is hit
   currently lists all functions by its name and offset. But this becomes
   ambiguous when there are several functions with the same name. Add a
   tracing option that changes the output to be that of _text+offset
   instead. Now a user space tool can use this information to map the
   _text+offset to the unique function it is counting.
 
 - Report bad dynamic event command
 
   If a bad command is passed to the dynamic_events file, report it properly
   in the error log.
 
 - Clean up tracer options
 
   Clean up the tracer option code a bit, by removing some useless code and
   also using switch statements instead of a series of if statements.
 
 - Have tracing options be instance specific
 
   Tracers can have their own options (function tracer, irqsoff tracer,
   function graph tracer, etc). But now that the same tracer can be enabled
   in multiple trace instances, their options are still global. The API is
   per instance, thus changing one affects other instances. This isn't even
   consistent, as the option take affect differently depending on when an
   tracer started in an instance.  Make the options for instances only affect
   the instance it is changed under.
 
 - Optimize pid_list lock contention
 
   Whenever the pid_list is read, it uses a spin lock. This happens at every
   sched switch. Taking the lock at sched switch can be removed by instead
   using a seqlock counter.
 
 - Clean up the trace trigger structures
 
   The trigger code uses two different structures to implement a single
   tigger. This was due to trying to reuse code for the two different types
   of triggers (always on trigger, and count limited trigger). But by adding
   a single field to one structure, the other structure could be absorbed
   into the first structure making he code easier to understand.
 
 - Create a bulk garbage collector for trace triggers
 
   If user space has triggers for several hundreds of events and then removes
   them, it can take several seconds to complete. This is because each
   removal calls the slow tracepoint_synchronize_unregister() that can take
   hundreds of milliseconds to complete. Instead, create a helper thread that
   will do the clean up. When a trigger is removed, it will create the
   kthread if it isn't already created, and then add the trigger to a llist.
   The kthread will take the items off the llist, call
   tracepoint_synchronize_unregister(), and then remove the items it took
   off. It will then check if there's more items to free before sleeping.
 
   This makes user space removing all these triggers to finish in less than a
   second.
 
 - Allow function tracing of some of the tracing infrastructure code
 
   Because the tracing code can cause recursion issues if it is traced by the
   function tracer the entire tracing directory disables function tracing.
   But not all of tracing causes issues if it is traced. Namely, the event
   tracing code. Add a config that enables some of the tracing code to be
   traced to help in debugging it. Note, when this is enabled, it does add
   noise to general function tracing, especially if events are enabled as
   well (which is a common case).
 
 - Add boot-time backup instance for persistent buffer
 
   The persistent ring buffer is used mostly for kernel crash analysis in the
   field. One issue is that if there's a crash, the data in the persistent
   ring buffer must be read before tracing can begin using it. This slows
   down the boot process. Once tracing starts in the persistent ring buffer,
   the old data must be freed and the addresses no longer match and old
   events can't be in the buffer with new events.
 
   Create a way to create a backup buffer that copies the persistent ring
   buffer at boot up. Then after a crash, the always on tracer can begin
   immediately as well as the normal boot process while the crash analysis
   tooling uses the backup buffer. After the backup buffer is finished being
   read, it can be removed.
 
 - Enable function graph args and return address options at the same time
 
   Currently the when reading of arguments in the function graph tracer is
   enabled, the option to record the parent function in the entry event can
   not be enabled. Update the code so that it can.
 
 - Add new struct_offset() helper macro
 
   Add a new macro that takes a pointer to a structure and a name of one of
   its members and it will return the offset of that member. This allows the
   ring buffer code to simplify the following:
 
   From:  size = struct_size(entry, buf, cnt - sizeof(entry->id));
     To:  size = struct_offset(entry, id) + cnt;
 
   There should be other simplifications that this macro can help out with as
   well.
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Merge tag 'trace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Extend tracing option mask to 64 bits

   The trace options were defined by a 32 bit variable. This limits the
   tracing instances to have a total of 32 different options. As that
   limit has been hit, and more options are being added, increase the
   option mask to a 64 bit number, doubling the number of options
   available.

   As this is required for the kprobe topic branches as well as the
   tracing topic branch, a separate branch was created and merged into
   both.

 - Make trace_user_fault_read() available for the rest of tracing

   The function trace_user_fault_read() is used by trace_marker file
   read to allow reading user space to be done fast and without locking
   or allocations. Make this available so that the system call trace
   events can use it too.

 - Have system call trace events read user space values

   Now that the system call trace events callbacks are called in a
   faultable context, take advantage of this and read the user space
   buffers for various system calls. For example, show the path name of
   the openat system call instead of just showing the pointer to that
   path name in user space. Also show the contents of the buffer of the
   write system call. Several system call trace events are updated to
   make tracing into a light weight strace tool for all applications in
   the system.

 - Update perf system call tracing to do the same

 - And a config and syscall_user_buf_size file to control the size of
   the buffer

   Limit the amount of data that can be read from user space. The
   default size is 63 bytes but that can be expanded to 165 bytes.

 - Allow the persistent ring buffer to print system calls normally

   The persistent ring buffer prints trace events by their type and
   ignores the print_fmt. This is because the print_fmt may change from
   kernel to kernel. As the system call output is fixed by the system
   call ABI itself, there's no reason to limit that. This makes reading
   the system call events in the persistent ring buffer much nicer and
   easier to understand.

 - Add options to show text offset to function profiler

   The function profiler that counts the number of times a function is
   hit currently lists all functions by its name and offset. But this
   becomes ambiguous when there are several functions with the same
   name.

   Add a tracing option that changes the output to be that of
   '_text+offset' instead. Now a user space tool can use this
   information to map the '_text+offset' to the unique function it is
   counting.

 - Report bad dynamic event command

   If a bad command is passed to the dynamic_events file, report it
   properly in the error log.

 - Clean up tracer options

   Clean up the tracer option code a bit, by removing some useless code
   and also using switch statements instead of a series of if
   statements.

 - Have tracing options be instance specific

   Tracers can have their own options (function tracer, irqsoff tracer,
   function graph tracer, etc). But now that the same tracer can be
   enabled in multiple trace instances, their options are still global.
   The API is per instance, thus changing one affects other instances.
   This isn't even consistent, as the option take affect differently
   depending on when an tracer started in an instance. Make the options
   for instances only affect the instance it is changed under.

 - Optimize pid_list lock contention

   Whenever the pid_list is read, it uses a spin lock. This happens at
   every sched switch. Taking the lock at sched switch can be removed by
   instead using a seqlock counter.

 - Clean up the trace trigger structures

   The trigger code uses two different structures to implement a single
   tigger. This was due to trying to reuse code for the two different
   types of triggers (always on trigger, and count limited trigger). But
   by adding a single field to one structure, the other structure could
   be absorbed into the first structure making he code easier to
   understand.

 - Create a bulk garbage collector for trace triggers

   If user space has triggers for several hundreds of events and then
   removes them, it can take several seconds to complete. This is
   because each removal calls tracepoint_synchronize_unregister() that
   can take hundreds of milliseconds to complete.

   Instead, create a helper thread that will do the clean up. When a
   trigger is removed, it will create the kthread if it isn't already
   created, and then add the trigger to a llist. The kthread will take
   the items off the llist, call tracepoint_synchronize_unregister(),
   and then remove the items it took off. It will then check if there's
   more items to free before sleeping.

   This makes user space removing all these triggers to finish in less
   than a second.

 - Allow function tracing of some of the tracing infrastructure code

   Because the tracing code can cause recursion issues if it is traced
   by the function tracer the entire tracing directory disables function
   tracing. But not all of tracing causes issues if it is traced.
   Namely, the event tracing code. Add a config that enables some of the
   tracing code to be traced to help in debugging it. Note, when this is
   enabled, it does add noise to general function tracing, especially if
   events are enabled as well (which is a common case).

 - Add boot-time backup instance for persistent buffer

   The persistent ring buffer is used mostly for kernel crash analysis
   in the field. One issue is that if there's a crash, the data in the
   persistent ring buffer must be read before tracing can begin using
   it. This slows down the boot process. Once tracing starts in the
   persistent ring buffer, the old data must be freed and the addresses
   no longer match and old events can't be in the buffer with new
   events.

   Create a way to create a backup buffer that copies the persistent
   ring buffer at boot up. Then after a crash, the always on tracer can
   begin immediately as well as the normal boot process while the crash
   analysis tooling uses the backup buffer. After the backup buffer is
   finished being read, it can be removed.

 - Enable function graph args and return address options at the same
   time

   Currently the when reading of arguments in the function graph tracer
   is enabled, the option to record the parent function in the entry
   event can not be enabled. Update the code so that it can.

 - Add new struct_offset() helper macro

   Add a new macro that takes a pointer to a structure and a name of one
   of its members and it will return the offset of that member. This
   allows the ring buffer code to simplify the following:

   From:  size = struct_size(entry, buf, cnt - sizeof(entry->id));
     To:  size = struct_offset(entry, id) + cnt;

   There should be other simplifications that this macro can help out
   with as well

* tag 'trace-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (42 commits)
  overflow: Introduce struct_offset() to get offset of member
  function_graph: Enable funcgraph-args and funcgraph-retaddr to work simultaneously
  tracing: Add boot-time backup of persistent ring buffer
  ftrace: Allow tracing of some of the tracing code
  tracing: Use strim() in trigger_process_regex() instead of skip_spaces()
  tracing: Add bulk garbage collection of freeing event_trigger_data
  tracing: Remove unneeded event_mutex lock in event_trigger_regex_release()
  tracing: Merge struct event_trigger_ops into struct event_command
  tracing: Remove get_trigger_ops() and add count_func() from trigger ops
  tracing: Show the tracer options in boot-time created instance
  ftrace: Avoid redundant initialization in register_ftrace_direct
  tracing: Remove unused variable in tracing_trace_options_show()
  fgraph: Make fgraph_no_sleep_time signed
  tracing: Convert function graph set_flags() to use a switch() statement
  tracing: Have function graph tracer option sleep-time be per instance
  tracing: Move graph-time out of function graph options
  tracing: Have function graph tracer option funcgraph-irqs be per instance
  trace/pid_list: optimize pid_list->lock contention
  tracing: Have function graph tracer define options per instance
  tracing: Have function tracer define options per instance
  ...
2025-12-05 09:51:37 -08:00
Tomas Glozar
b9f6a40dc3 Documentation/trace: Specify exact priority for timerlat
The timerlat tracer documentation mentions that threads are created with
real-time priority, but does not mention which priority and scheduling
class is used.

Add the information so that users do not have to look it up in
trace_osnoise.c.

Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251010083338.478961-9-tglozar@redhat.com>
2025-11-05 11:19:20 -07:00
Steven Rostedt
299ea67e6a tracing: Add a config and syscall_user_buf_size file to limit amount written
When a system call that can copy user space addresses into the ring
buffer, it can copy up to 511 bytes of data. This can waste precious ring
buffer space if the user isn't interested in the output. Add a new file
"syscall_user_buf_size" that gets initialized to a new config
CONFIG_SYSCALL_BUF_SIZE_DEFAULT that defaults to 63.

The config also is used to limit how much perf can read from user space.

Also lower the max down to 165, as this isn't to record everything that a
system call may be passing through to the kernel. 165 is more than enough.

The reason for 165 is because adding one for the nul terminating byte, as
well as possibly needing to append the "..." string turns it into 170
bytes. As this needs to save up to 3 arguments and 3 * 170 is 510 which
fits nicely in 512 bytes (a power of 2).

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Takaya Saeki <takayas@google.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ian Rogers <irogers@google.com>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/20251028231148.260068913@kernel.org
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-10-28 20:10:59 -04:00
Bagas Sanjaya
b8874ea3d0 Documentation: trace: histogram: Convert ftrace docs cross-reference
In brief "Extended error information" section, details on error
condition is referred to ftrace docs, which is written in :file:
directive instead of a proper cross-reference. Convert it.

Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250916054202.582074-7-bagasdotme@gmail.com>
2025-09-18 11:49:26 -06:00
Bagas Sanjaya
fa06220f34 Documentation: trace: histogram-design: Wrap introductory note in note:: directive
Use Sphinx note:: directive for the introductory note at the beginning
of docs, instead of aligned-text paragraph that renders as definition
list.

Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250916054202.582074-6-bagasdotme@gmail.com>
2025-09-18 11:49:26 -06:00
Bagas Sanjaya
8c716e87ea Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram
Section heading for sched_waking histogram is shown as normal paragraph
instead due to codeblock marker for the following diagram being in the
same line as the section underline. Separate them.

Fixes: daceabf1b4 ("tracing/doc: Fix ascii-art in histogram-design.rst")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250916054202.582074-5-bagasdotme@gmail.com>
2025-09-18 11:49:26 -06:00
Bagas Sanjaya
f867a298ac Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text
Diagram explanation text is supposed to be interleaved commentary
between diagram parts that are spread out, but it outputs ugly in
htmldocs due to trailing vertices as if both the explanation and the
diagram are in the same literal code block.

Trim trailing vertices.

Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250916054202.582074-4-bagasdotme@gmail.com>
2025-09-18 11:49:26 -06:00
Bagas Sanjaya
348b7ca8d3 Documentation: trace: histogram: Fix histogram trigger subsection number order
Section numbering in subsections of "Histogram Trigger Command" sections
is inconsistent in order. In particular, "'hist' trigger examples" is
erroneously numbered as 6.2, which is a leftover from  b8df4a3634
("tracing: Move hist trigger Documentation to histogram.txt").

Fix the order.

Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250916054202.582074-3-bagasdotme@gmail.com>
2025-09-18 11:49:26 -06:00
Ryan Chung
b65988af71 tracing: fix grammar error in debugging.rst
Signed-off-by: Ryan Chung <seokwoo.chung130@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250831101736.11519-3-seokwoo.chung130@gmail.com
2025-09-03 15:31:48 -06:00
Ryan Chung
d5958c8a09 tracing: rephrase for clearer documentation
Signed-off-by: Ryan Chung <seokwoo.chung130@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250831101736.11519-2-seokwoo.chung130@gmail.com
2025-09-03 15:31:30 -06:00
Mehdi Ben Hadj Khelifa
915fb5caad docs: Corrected typo in trace/events
-Changed 'Dyamically' to 'Dynamically' in trace/events.rst

under sections 7.1 and 7.3

Signed-off-by: Mehdi Ben Hadj Khelifa <mehdi.benhadjkhelifa@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250819085040.974388-1-mehdi.benhadjkhelifa@gmail.com
2025-08-21 11:59:11 -06:00
Jonathan Corbet
4e18a0b090 Merge branch 'bjorn' into docs-mw
A big set of typo fixes from Bjorn Helgaas
2025-08-18 10:40:16 -06:00
Bjorn Helgaas
29fe206065 Documentation: Fix trace typos
Fix typos.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250813200526.290420-9-helgaas@kernel.org
2025-08-18 10:31:20 -06:00
Gopi Krishna Menon
70d476b63a Documentation/rv: Fix minor typo in monitor_synthesis page
Specifically, fix spelling of "practice"

Signed-off-by: Gopi Krishna Menon <krishnagopi487@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250810111249.93181-1-krishnagopi487@gmail.com
2025-08-12 12:41:20 -06:00
Linus Torvalds
d6f38c1239 tracing changes for 6.17
- Deprecate auto-mounting tracefs to /sys/kernel/debug/tracing
 
   When tracefs was first introduced back in 2014, the directory
   /sys/kernel/tracing was added and is the designated location to mount
   tracefs. To keep backward compatibility, tracefs was auto-mounted in
   /sys/kernel/debug/tracing as well.
 
   All distros now mount tracefs on /sys/kernel/tracing. Having it seen in two
   different locations has lead to various issues and inconsistencies.
 
   The VFS folks have to also maintain debugfs_create_automount() for this
   single user.
 
   It's been over 10 years. Tooling and scripts should start replacing the
   debugfs location with the tracefs one. The reason tracefs was created in the
   first place was to allow access to the tracing facilities without the need
   to configure debugfs into the kernel. Using tracefs should now be more
   robust.
 
   A new config is created: CONFIG_TRACEFS_AUTOMOUNT_DEPRECATED
   which is default y, so that the kernel is still built with the automount.
   This config allows those that want to remove the automount from debugfs to
   do so.
 
   When tracefs is accessed from /sys/kernel/debug/tracing, the following
   printk is triggerd:
 
    pr_warn("NOTICE: Automounting of tracing to debugfs is deprecated and will be removed in 2030\n");
 
   This gives users another 5 years to fix their scripts.
 
 - Use queue_rcu_work() instead of call_rcu() for freeing event filters
 
   The number of filters to be free can be many depending on the number of
   events within an event system. Freeing them from softirq context can
   potentially cause undesired latency. Use the RCU workqueue to free them
   instead.
 
 - Remove pointless memory barriers in latency code
 
   Memory barriers were added to some of the latency code a long time ago with
   the idea of "making them visible", but that's not what memory barriers are
   for. They are to synchronize access between different variables. There was
   no synchronization here making them pointless.
 
 - Remove "__attribute__()" from the type field of event format
 
   When LLVM is used to compile the kernel with CONFIG_DEBUG_INFO_BTF=y and
   PAHOLE_HAS_BTF_TAG=y, some of the format fields get expanded with the
   following:
 
     field:const char * filename;      offset:24;      size:8; signed:0;
 
   Turns into:
 
     field:const char __attribute__((btf_type_tag("user"))) * filename;      offset:24;      size:8; signed:0;
 
   This confuses parsers. Add code to strip these tags from the strings.
 
 - Add eprobe config option CONFIG_EPROBE_EVENTS
 
   Eprobes were added back in 5.15 but were only enabled when another probe was
   enabled (kprobe, fprobe, uprobe, etc). The eprobes had no config option
   of their own. Add one as they should be a separate entity.
 
   It's default y to keep with the old kernels but still has dependencies on
   TRACING and HAVE_REGS_AND_STACK_ACCESS_API.
 
 - Add eprobe documentation
 
   When eprobes were added back in 5.15 no documentation was added to describe
   them. This needs to be rectified.
 
 - Replace open coded cpumask_next_wrap() in move_to_next_cpu()
 
 - Have preemptirq_delay_run() use off-stack CPU mask
 
 - Remove obsolete comment about pelt_cfs event
 
   DECLARE_TRACE() appends "_tp" to trace events now, but the comment above
   pelt_cfs still mentioned appending it manually.
 
 - Remove EVENT_FILE_FL_SOFT_MODE flag
 
   The SOFT_MODE flag was required when the soft enabling and disabling of
   trace events was first introduced. But there was a bug with this approach
   as it only worked for a single instance. When multiple users required soft
   disabling and disabling the code was changed to have a ref count. The
   SOFT_MODE flag is now set iff the ref count is non zero. This is redundant
   and just reading the ref count is good enough.
 
 - Fix typo in comment
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Merge tag 'trace-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Deprecate auto-mounting tracefs to /sys/kernel/debug/tracing

   When tracefs was first introduced back in 2014, the directory
   /sys/kernel/tracing was added and is the designated location to mount
   tracefs. To keep backward compatibility, tracefs was auto-mounted in
   /sys/kernel/debug/tracing as well.

   All distros now mount tracefs on /sys/kernel/tracing. Having it seen
   in two different locations has lead to various issues and
   inconsistencies.

   The VFS folks have to also maintain debugfs_create_automount() for
   this single user.

   It's been over 10 years. Tooling and scripts should start replacing
   the debugfs location with the tracefs one. The reason tracefs was
   created in the first place was to allow access to the tracing
   facilities without the need to configure debugfs into the kernel.
   Using tracefs should now be more robust.

   A new config is created: CONFIG_TRACEFS_AUTOMOUNT_DEPRECATED which is
   default y, so that the kernel is still built with the automount. This
   config allows those that want to remove the automount from debugfs to
   do so.

   When tracefs is accessed from /sys/kernel/debug/tracing, the
   following printk is triggerd:

     pr_warn("NOTICE: Automounting of tracing to debugfs is deprecated and will be removed in 2030\n");

   This gives users another 5 years to fix their scripts.

 - Use queue_rcu_work() instead of call_rcu() for freeing event filters

   The number of filters to be free can be many depending on the number
   of events within an event system. Freeing them from softirq context
   can potentially cause undesired latency. Use the RCU workqueue to
   free them instead.

 - Remove pointless memory barriers in latency code

   Memory barriers were added to some of the latency code a long time
   ago with the idea of "making them visible", but that's not what
   memory barriers are for. They are to synchronize access between
   different variables. There was no synchronization here making them
   pointless.

 - Remove "__attribute__()" from the type field of event format

   When LLVM is used to compile the kernel with CONFIG_DEBUG_INFO_BTF=y
   and PAHOLE_HAS_BTF_TAG=y, some of the format fields get expanded with
   the following:

     field:const char * filename;      offset:24;      size:8; signed:0;

   Turns into:

     field:const char __attribute__((btf_type_tag("user"))) * filename;      offset:24;      size:8; signed:0;

   This confuses parsers. Add code to strip these tags from the strings.

 - Add eprobe config option CONFIG_EPROBE_EVENTS

   Eprobes were added back in 5.15 but were only enabled when another
   probe was enabled (kprobe, fprobe, uprobe, etc). The eprobes had no
   config option of their own. Add one as they should be a separate
   entity.

   It's default y to keep with the old kernels but still has
   dependencies on TRACING and HAVE_REGS_AND_STACK_ACCESS_API.

 - Add eprobe documentation

   When eprobes were added back in 5.15 no documentation was added to
   describe them. This needs to be rectified.

 - Replace open coded cpumask_next_wrap() in move_to_next_cpu()

 - Have preemptirq_delay_run() use off-stack CPU mask

 - Remove obsolete comment about pelt_cfs event

   DECLARE_TRACE() appends "_tp" to trace events now, but the comment
   above pelt_cfs still mentioned appending it manually.

 - Remove EVENT_FILE_FL_SOFT_MODE flag

   The SOFT_MODE flag was required when the soft enabling and disabling
   of trace events was first introduced. But there was a bug with this
   approach as it only worked for a single instance. When multiple users
   required soft disabling and disabling the code was changed to have a
   ref count. The SOFT_MODE flag is now set iff the ref count is non
   zero. This is redundant and just reading the ref count is good
   enough.

 - Fix typo in comment

* tag 'trace-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  Documentation: tracing: Add documentation about eprobes
  tracing: Have eprobes have their own config option
  tracing: Remove "__attribute__()" from the type field of event format
  tracing: Deprecate auto-mounting tracefs in debugfs
  tracing: Fix comment in trace_module_remove_events()
  tracing: Remove EVENT_FILE_FL_SOFT_MODE flag
  tracing: Remove pointless memory barriers
  tracing/sched: Remove obsolete comment on suffixes
  kernel: trace: preemptirq_delay_test: use offstack cpu mask
  tracing: Use queue_rcu_work() to free filters
  tracing: Replace opencoded cpumask_next_wrap() in move_to_next_cpu()
2025-08-01 10:29:36 -07:00
Linus Torvalds
b1cce98493 It has been a relatively busy cycle for docs, especially the build system:
- The Perl kernel-doc script was added to 2.3.52pre1 just after the turn of
   the millennium.  Over the following 25 years, it accumulated a vast
   amount of cruft, all in a language few people want to deal with anymore.
   Mauro's Python replacement in 6.16 faithfully reproduced all of the cruft
   in the hope of avoiding regressions.  Now that we have a more reasonable
   code base, though, we can work on cleaning it up; many of the changes
   this time around are toward that end.
 
 - A reorganization of the ext4 docs into the usual TOC format.
 
 - Various Chinese translations and updates.
 
 - A new script from Mauro to help with docs-build testing.
 
 - A new document for linked lists
 
 - A sweep through MAINTAINERS fixing broken GitHub git:// repository links.
 
 ...and lots of fixes and updates.
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Merge tag 'docs-6.17' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a relatively busy cycle for docs, especially the build
  system:

   - The Perl kernel-doc script was added to 2.3.52pre1 just after the
     turn of the millennium. Over the following 25 years, it accumulated
     a vast amount of cruft, all in a language few people want to deal
     with anymore. Mauro's Python replacement in 6.16 faithfully
     reproduced all of the cruft in the hope of avoiding regressions.

     Now that we have a more reasonable code base, though, we can work
     on cleaning it up; many of the changes this time around are toward
     that end.

   - A reorganization of the ext4 docs into the usual TOC format.

   - Various Chinese translations and updates.

   - A new script from Mauro to help with docs-build testing.

   - A new document for linked lists

   - A sweep through MAINTAINERS fixing broken GitHub git:// repository
     links.

  ...and lots of fixes and updates"

* tag 'docs-6.17' of git://git.lwn.net/linux: (147 commits)
  scripts: add origin commit identification based on specific patterns
  sphinx: kernel_abi: fix performance regression with O=<dir>
  Documentation: core-api: entry: Replace deprecated KVM entry/exit functions
  docs: fault-injection: drop reference to md-faulty
  docs: document linked lists
  scripts: kdoc: make it backward-compatible with Python 3.7
  docs: kernel-doc: emit warnings for ancient versions of Python
  Documentation/rtla: Describe exit status
  Documentation/rtla: Add include common_appendix.rst
  docs: kernel: Clarify printk_ratelimit_burst reset behavior
  Documentation: ioctl-number: Don't repeat macro names
  Documentation: ioctl-number: Shorten macros table
  Documentation: ioctl-number: Correct full path to papr-physical-attestation.h
  Documentation: ioctl-number: Extend "Include File" column width
  Documentation: ioctl-number: Fix linuxppc-dev mailto link
  overlayfs.rst: fix typos
  docs: kdoc: emit a warning for ancient versions of Python
  docs: kdoc: clean up check_sections()
  docs: kdoc: directly access the always-there KdocItem fields
  docs: kdoc: straighten up dump_declaration()
  ...
2025-07-31 08:36:51 -07:00
Linus Torvalds
4ff261e725 Runtime verification changes for 6.17
- Added Linear temporal logic monitors for RT application
 
   Real-time applications may have design flaws causing them to have
   unexpected latency. For example, the applications may raise page faults, or
   may be blocked trying to take a mutex without priority inheritance.
 
   However, while attempting to implement DA monitors for these real-time
   rules, deterministic automaton is found to be inappropriate as the
   specification language. The automaton is complicated, hard to understand,
   and error-prone.
 
   For these cases, linear temporal logic is found to be more suitable. The
   LTL is more concise and intuitive.
 
 - Make printk_deferred() public
 
   The new monitors needed access to printk_deferred(). Make them visible for
   the entire kernel.
 
 - Add a vpanic() to allow for va_list to be passed to panic.
 
 - Add rtapp container monitor.
 
   A collection of monitors that check for common problems with real-time
   applications that cause unexpected latency.
 
 - Add page fault tracepoints to risc-v
 
   These tracepoints are necessary to for the RV monitor to run on risc-v.
 
 - Fix the behaviour of the rv tool with -s and idle tasks.
 
 - Allow the rv tool to gracefully terminate with SIGTERM
 
 - Adjusts dot2c not to create lines over 100 columns
 
 - Properly order nested monitors in the RV Kconfig file
 
 - Return the registration error in all DA monitor instead of 0
 
 - Update and add new sched collection monitors
 
   Replace tss and sncid monitors with more complete sts:
   Not only prove that switches occur in scheduling context and scheduling
   needs interrupt disabled but also that each call to the scheduler
   disables interrupts to (optionally) switch.
 
   New monitor: nrp
    Preemption requires need resched which is cleared by any switch
    (includes a non optimal workaround for /nested/ preemptions)
 
   New monitor: sssw
    suspension requires setting the task to sleepable and, after the
    switch occurs, the task requires a wakeup to come back to runnable
 
   New monitor: opid
    waking and need-resched operations occur with interrupts and
    preemption disabled or in IRQ without explicitly disabling preemption
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Merge tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull runtime verification updates from Steven Rostedt:

 - Added Linear temporal logic monitors for RT application

   Real-time applications may have design flaws causing them to have
   unexpected latency. For example, the applications may raise page
   faults, or may be blocked trying to take a mutex without priority
   inheritance.

   However, while attempting to implement DA monitors for these
   real-time rules, deterministic automaton is found to be inappropriate
   as the specification language. The automaton is complicated, hard to
   understand, and error-prone.

   For these cases, linear temporal logic is found to be more suitable.
   The LTL is more concise and intuitive.

 - Make printk_deferred() public

   The new monitors needed access to printk_deferred(). Make them
   visible for the entire kernel.

 - Add a vpanic() to allow for va_list to be passed to panic.

 - Add rtapp container monitor.

   A collection of monitors that check for common problems with
   real-time applications that cause unexpected latency.

 - Add page fault tracepoints to risc-v

   These tracepoints are necessary to for the RV monitor to run on
   risc-v.

 - Fix the behaviour of the rv tool with -s and idle tasks.

 - Allow the rv tool to gracefully terminate with SIGTERM

 - Adjusts dot2c not to create lines over 100 columns

 - Properly order nested monitors in the RV Kconfig file

 - Return the registration error in all DA monitor instead of 0

 - Update and add new sched collection monitors

   Replace tss and sncid monitors with more complete sts:

   Not only prove that switches occur in scheduling context and scheduling
   needs interrupt disabled but also that each call to the scheduler
   disables interrupts to (optionally) switch.

   New monitor: nrp
     Preemption requires need resched which is cleared by any switch
     (includes a non optimal workaround for /nested/ preemptions)

   New monitor: sssw
     suspension requires setting the task to sleepable and, after the
     switch occurs, the task requires a wakeup to come back to runnable

   New monitor: opid
      waking and need-resched operations occur with interrupts and
      preemption disabled or in IRQ without explicitly disabling
      preemption"

* tag 'trace-rv-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (48 commits)
  rv: Add opid per-cpu monitor
  rv: Add nrp and sssw per-task monitors
  rv: Replace tss and sncid monitors with more complete sts
  sched: Adapt sched tracepoints for RV task model
  rv: Retry when da monitor detects race conditions
  rv: Adjust monitor dependencies
  rv: Use strings in da monitors tracepoints
  rv: Remove trailing whitespace from tracepoint string
  rv: Add da_handle_start_run_event_ to per-task monitors
  rv: Fix wrong type cast in reactors_show() and monitor_reactor_show()
  rv: Fix wrong type cast in monitors_show()
  rv: Remove struct rv_monitor::reacting
  rv: Remove rv_reactor's reference counter
  rv: Merge struct rv_reactor_def into struct rv_reactor
  rv: Merge struct rv_monitor_def into struct rv_monitor
  rv: Remove unused field in struct rv_monitor_def
  rv: Return init error when registering monitors
  verification/rvgen: Organise Kconfig entries for nested monitors
  tools/dot2c: Fix generated files going over 100 column limit
  tools/rv: Stop gracefully also on SIGTERM
  ...
2025-07-30 16:23:12 -07:00
Steven Rostedt
623526ba89 Documentation: tracing: Add documentation about eprobes
Eprobes was added back in 5.15, but was never documented. It became a
"secret" interface even though it has been a topic of several
presentations. For some reason, when eprobes was added, documenting it
never became a priority, until now.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/20250730140945.528135548@kernel.org
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-30 10:38:43 -04:00
Gabriele Monaco
614384533d rv: Add opid per-cpu monitor
Add a per-cpu monitor as part of the sched model:
* opid: operations with preemption and irq disabled
    Monitor to ensure wakeup and need_resched occur with irq and
    preemption disabled or in irq handlers.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-10-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Acked-by: Nam Cao <namcao@linutronix.de>
Tested-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:35 -04:00
Gabriele Monaco
e8440a88e5 rv: Add nrp and sssw per-task monitors
Add 2 per-task monitors as part of the sched model:

* nrp: need-resched preempts
    Monitor to ensure preemption requires need resched.
* sssw: set state sleep and wakeup
    Monitor to ensure sched_set_state to sleepable leads to sleeping and
    sleeping tasks require wakeup.

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-9-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Acked-by: Nam Cao <namcao@linutronix.de>
Tested-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Gabriele Monaco
d0096c2f9c rv: Replace tss and sncid monitors with more complete sts
The tss monitor currently guarantees task switches can happen only while
scheduling, whereas the sncid monitor enforces scheduling occurs with
interrupt disabled.

Replace the monitors with a more comprehensive specification which
implies both but also ensures that:
* each scheduler call disable interrupts to switch
* each task switch happens with interrupts disabled

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/20250728135022.255578-8-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-28 16:47:34 -04:00
Nam Cao
8cfcf9b0e9 verification/rvgen: Support the 'next' operator
The 'next' operator is a unary operator. It is defined as: "next time, the
operand must be true".

Support this operator. For RV monitors, "next time" means the next
invocation of ltl_validate().

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/9c32cec04dd18d2e956fddd84b0e0a2503daa75a.1752239482.git.namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Tested-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:43:23 -04:00
Nam Cao
e93648e862 Documentation/rv: Add documentation for linear temporal logic monitors
Add documents describing linear temporal logic runtime verification
monitors and how to generate them using rvgen.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/be13719e66fd8da147d7c69d5365aa23c52b743f.1751634289.git.namcao@linutronix.de
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:42:47 -04:00
Nam Cao
f40a7c0602 Documentation/rv: Prepare monitor synthesis document for LTL inclusion
Monitor synthesis from deterministic automaton and linear temporal logic
have a lot in common. Therefore a single document should describe both.

Change da_monitor_synthesis.rst to monitor_synthesis.rst. LTL monitor
synthesis will be added to this file by a follow-up commit.

This makes the diff far easier to read. If renaming and adding LTL info is
done in a single commit, git wouldn't recognize it as a rename, but a file
removal and a file addition.

While at it, correct the old dot2k commands to the new rvgen commands.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/d91c6e4600287f4732d68a014219e576a75ce6dc.1751634289.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-24 10:42:46 -04:00
Steven Rostedt
4d6d0a6263 tracing: Remove redundant config HAVE_FTRACE_MCOUNT_RECORD
Ftrace is tightly coupled with architecture specific code because it
requires the use of trampolines written in assembly. This means that when
a new feature or optimization is made, it must be done for all
architectures. To simplify the approach, CONFIG_HAVE_FTRACE_* configs are
added to denote which architecture has the new enhancement so that other
architectures can still function until they too have been updated.

The CONFIG_HAVE_FTRACE_MCOUNT was added to help simplify the
DYNAMIC_FTRACE work, but now every architecture that implements
DYNAMIC_FTRACE also has HAVE_FTRACE_MCOUNT set too, making it redundant
with the HAVE_DYNAMIC_FTRACE.

Remove the HAVE_FTRACE_MCOUNT config and use DYNAMIC_FTRACE directly where
applicable.

Link: https://lore.kernel.org/all/20250703154916.48e3ada7@gandalf.local.home/

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20250704104838.27a18690@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-22 20:15:56 -04:00
Nam Cao
670ff946b9 rv: Add documentation for rtapp monitor
Add documentation describing the rtapp monitor.

Cc: John Ogness <john.ogness@linutronix.de>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/df0242d74c12511e82cc9d73c082def91a160c74.1752088709.git.namcao@linutronix.de
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-07-09 15:27:02 -04:00
Ahelenia Ziemiańska
f55b3ca3cf tracing: doc: fix "for a while" typo
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/xygdnynf7m55p7d27ovzqtdjaa7pua3bxuk5c22cnmoovaji5e@tarta.nabijaczleweli.xyz
2025-07-08 08:14:28 -06:00
Runji Liu
ea08e53d4d docs: trace: boottime-trace.rst: fix typo
Replace misspelled "eariler" with "earlier" and drop the stray period
after "example".

Signed-off-by: Runji Liu <runjiliu.tech@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250526134046.1042-1-runjiliu.tech@gmail.com
2025-06-09 14:35:07 -06:00
Linus Torvalds
c26f4fbd58 Char/Misc/IIO pull request for 6.16-rc1
Here is the big char/misc/iio and other small driver subsystem pull
 request for 6.16-rc1.
 
 Overall, a lot of individual changes, but nothing major, just the normal
 constant forward progress of new device support and cleanups to existing
 subsystems.  Highlights in here are:
   - Large IIO driver updates and additions and device tree changes
   - Android binder bugfixes and logfile fixes
   - mhi driver updates
   - comedi driver updates
   - counter driver updates and additions
   - coresight driver updates and additions
   - echo driver removal as there are no in-kernel users of it
   - nvmem driver updates
   - spmi driver updates
   - new amd-sbi driver "subsystem" and drivers added
   - rust miscdriver binding documentation fix
   - other small driver fixes and updates (uio, w1, acrn, hpet, xillybus,
     cardreader drivers, fastrpc and others.)
 
 All of these have been in linux-next for quite a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc / iio driver updates from Greg KH:
 "Here is the big char/misc/iio and other small driver subsystem pull
  request for 6.16-rc1.

  Overall, a lot of individual changes, but nothing major, just the
  normal constant forward progress of new device support and cleanups to
  existing subsystems. Highlights in here are:

   - Large IIO driver updates and additions and device tree changes

   - Android binder bugfixes and logfile fixes

   - mhi driver updates

   - comedi driver updates

   - counter driver updates and additions

   - coresight driver updates and additions

   - echo driver removal as there are no in-kernel users of it

   - nvmem driver updates

   - spmi driver updates

   - new amd-sbi driver "subsystem" and drivers added

   - rust miscdriver binding documentation fix

   - other small driver fixes and updates (uio, w1, acrn, hpet,
     xillybus, cardreader drivers, fastrpc and others)

  All of these have been in linux-next for quite a while with no
  reported problems"

* tag 'char-misc-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (390 commits)
  binder: fix yet another UAF in binder_devices
  counter: microchip-tcb-capture: Add watch validation support
  dt-bindings: iio: adc: Add ROHM BD79100G
  iio: adc: add support for Nuvoton NCT7201
  dt-bindings: iio: adc: add NCT7201 ADCs
  iio: chemical: Add driver for SEN0322
  dt-bindings: trivial-devices: Document SEN0322
  iio: adc: ad7768-1: reorganize driver headers
  iio: bmp280: zero-init buffer
  iio: ssp_sensors: optimalize -> optimize
  HID: sensor-hub: Fix typo and improve documentation
  iio: admv1013: replace redundant ternary operator with just len
  iio: chemical: mhz19b: Fix error code in probe()
  iio: adc: at91-sama5d2: use IIO_DECLARE_BUFFER_WITH_TS
  iio: accel: sca3300: use IIO_DECLARE_BUFFER_WITH_TS
  iio: adc: ad7380: use IIO_DECLARE_DMA_BUFFER_WITH_TS
  iio: adc: ad4695: rename AD4695_MAX_VIN_CHANNELS
  iio: adc: ad4695: use IIO_DECLARE_DMA_BUFFER_WITH_TS
  iio: introduce IIO_DECLARE_BUFFER_WITH_TS macros
  iio: make IIO_DMA_MINALIGN minimum of 8 bytes
  ...
2025-06-06 11:50:47 -07:00
Linus Torvalds
b78f1293f9 tracing updates for v6.16:
- Have module addresses get updated in the persistent ring buffer
 
   The addresses of the modules from the previous boot are saved in the
   persistent ring buffer. If the same modules are loaded and an address is
   in the old buffer points to an address that was both saved in the
   persistent ring buffer and is loaded in memory, shift the address to point
   to the address that is loaded in memory in the trace event.
 
 - Print function names for irqs off and preempt off callsites
 
   When ignoring the print fmt of a trace event and just printing the fields
   directly, have the fields for preempt off and irqs off events still show
   the function name (via kallsyms) instead of just showing the raw address.
 
 - Clean ups of the histogram code
 
   The histogram functions saved over 800 bytes on the stack to process
   events as they come in. Instead, create per-cpu buffers that can hold this
   information and have a separate location for each context level (thread,
   softirq, IRQ and NMI).
 
   Also add some more comments to the code.
 
 - Add "common_comm" field for histograms
 
   Add "common_comm" that uses the current->comm as a field in an event
   histogram and acts like any of the other fields of the event.
 
 - Show "subops" in the enabled_functions file
 
   When the function graph infrastructure is used, a subsystem has a "subops"
   that it attaches its callback function to. Instead of the
   enabled_functions just showing a function calling the function that calls
   the subops functions, also show the subops functions that will get called
   for that function too.
 
 - Add "copy_trace_marker" option to instances
 
   There are cases where an instance is created for tooling to write into,
   but the old tooling has the top level instance hardcoded into the
   application. New tools want to consume the data from an instance and not
   the top level buffer. By adding a copy_trace_marker option, whenever the
   top instance trace_marker is written into, a copy of it is also written
   into the instance with this option set. This allows new tools to read what
   old tools are writing into the top buffer.
 
   If this option is cleared by the top instance, then what is written into
   the trace_marker is not written into the top instance. This is a way to
   redirect the trace_marker writes into another instance.
 
 - Have tracepoints created by DECLARE_TRACE() use trace_<name>_tp()
 
   If a tracepoint is created by DECLARE_TRACE() instead of TRACE_EVENT(),
   then it will not be exposed via tracefs. Currently there's no way to
   differentiate in the kernel the tracepoint functions between those that
   are exposed via tracefs or not. A calling convention has been made
   manually to append a "_tp" prefix for events created by DECLARE_TRACE().
   Instead of doing this manually, force it so that all DECLARE_TRACE()
   events have this notation.
 
 - Use __string() for task->comm in some sched events
 
   Instead of hardcoding the comm to be TASK_COMM_LEN in some of the
   scheduler events use __string() which makes it dynamic. Note, if these
   events are parsed by user space it they may break, and the event may have
   to be converted back to the hardcoded size.
 
 - Have function graph "depth" be unsigned to the user
 
   Internally to the kernel, the "depth" field of the function graph event is
   signed due to -1 being used for end of boundary. What actually gets
   recorded in the event itself is zero or positive. Reflect this to user
   space by showing "depth" as unsigned int and be consistent across all
   events.
 
 - Allow an arbitrary long CPU string to osnoise_cpus_write()
 
   The filtering of which CPUs to write to can exceed 256 bytes. If a machine
   has 256 CPUs, and the filter is to filter every other CPU, the write would
   take a string larger than 256 bytes. Instead of using a fixed size buffer
   on the stack that is 256 bytes, allocate it to handle what is passed in.
 
 - Stop having ftrace check the per-cpu data "disabled" flag
 
   The "disabled" flag in the data structure passed to most ftrace functions
   is checked to know if tracing has been disabled or not. This flag was
   added back in 2008 before the ring buffer had its own way to disable
   tracing. The "disable" flag is now not always set when needed, and the
   ring buffer flag should be used in all locations where the disabled is
   needed. Since the "disable" flag is redundant and incorrect, stop using it.
   Fix up some locations that use the "disable" flag to use the ring buffer
   info.
 
 - Use a new tracer_tracing_disable/enable() instead of data->disable flag
 
   There's a few cases that set the data->disable flag to stop tracing, but
   this flag is not consistently used. It is also an on/off switch where if a
   function set it and calls another function that sets it, the called
   function may incorrectly enable it.
 
   Use a new trace_tracing_disable() and tracer_tracing_enable() that uses a
   counter and can be nested. These use the ring buffer flags which are
   always checked making the disabling more consistent.
 
 - Save the trace clock in the persistent ring buffer
 
   Save what clock was used for tracing in the persistent ring buffer and set
   it back to that clock after a reboot.
 
 - Remove unused reference to a per CPU data pointer in mmiotrace functions
 
 - Remove unused buffer_page field from trace_array_cpu structure
 
 - Remove more strncpy() instances
 
 - Other minor clean ups and fixes
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Merge tag 'trace-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Have module addresses get updated in the persistent ring buffer

   The addresses of the modules from the previous boot are saved in the
   persistent ring buffer. If the same modules are loaded and an address
   is in the old buffer points to an address that was both saved in the
   persistent ring buffer and is loaded in memory, shift the address to
   point to the address that is loaded in memory in the trace event.

 - Print function names for irqs off and preempt off callsites

   When ignoring the print fmt of a trace event and just printing the
   fields directly, have the fields for preempt off and irqs off events
   still show the function name (via kallsyms) instead of just showing
   the raw address.

 - Clean ups of the histogram code

   The histogram functions saved over 800 bytes on the stack to process
   events as they come in. Instead, create per-cpu buffers that can hold
   this information and have a separate location for each context level
   (thread, softirq, IRQ and NMI).

   Also add some more comments to the code.

 - Add "common_comm" field for histograms

   Add "common_comm" that uses the current->comm as a field in an event
   histogram and acts like any of the other fields of the event.

 - Show "subops" in the enabled_functions file

   When the function graph infrastructure is used, a subsystem has a
   "subops" that it attaches its callback function to. Instead of the
   enabled_functions just showing a function calling the function that
   calls the subops functions, also show the subops functions that will
   get called for that function too.

 - Add "copy_trace_marker" option to instances

   There are cases where an instance is created for tooling to write
   into, but the old tooling has the top level instance hardcoded into
   the application. New tools want to consume the data from an instance
   and not the top level buffer. By adding a copy_trace_marker option,
   whenever the top instance trace_marker is written into, a copy of it
   is also written into the instance with this option set. This allows
   new tools to read what old tools are writing into the top buffer.

   If this option is cleared by the top instance, then what is written
   into the trace_marker is not written into the top instance. This is a
   way to redirect the trace_marker writes into another instance.

 - Have tracepoints created by DECLARE_TRACE() use trace_<name>_tp()

   If a tracepoint is created by DECLARE_TRACE() instead of
   TRACE_EVENT(), then it will not be exposed via tracefs. Currently
   there's no way to differentiate in the kernel the tracepoint
   functions between those that are exposed via tracefs or not. A
   calling convention has been made manually to append a "_tp" prefix
   for events created by DECLARE_TRACE(). Instead of doing this
   manually, force it so that all DECLARE_TRACE() events have this
   notation.

 - Use __string() for task->comm in some sched events

   Instead of hardcoding the comm to be TASK_COMM_LEN in some of the
   scheduler events use __string() which makes it dynamic. Note, if
   these events are parsed by user space it they may break, and the
   event may have to be converted back to the hardcoded size.

 - Have function graph "depth" be unsigned to the user

   Internally to the kernel, the "depth" field of the function graph
   event is signed due to -1 being used for end of boundary. What
   actually gets recorded in the event itself is zero or positive.
   Reflect this to user space by showing "depth" as unsigned int and be
   consistent across all events.

 - Allow an arbitrary long CPU string to osnoise_cpus_write()

   The filtering of which CPUs to write to can exceed 256 bytes. If a
   machine has 256 CPUs, and the filter is to filter every other CPU,
   the write would take a string larger than 256 bytes. Instead of using
   a fixed size buffer on the stack that is 256 bytes, allocate it to
   handle what is passed in.

 - Stop having ftrace check the per-cpu data "disabled" flag

   The "disabled" flag in the data structure passed to most ftrace
   functions is checked to know if tracing has been disabled or not.
   This flag was added back in 2008 before the ring buffer had its own
   way to disable tracing. The "disable" flag is now not always set when
   needed, and the ring buffer flag should be used in all locations
   where the disabled is needed. Since the "disable" flag is redundant
   and incorrect, stop using it. Fix up some locations that use the
   "disable" flag to use the ring buffer info.

 - Use a new tracer_tracing_disable/enable() instead of data->disable
   flag

   There's a few cases that set the data->disable flag to stop tracing,
   but this flag is not consistently used. It is also an on/off switch
   where if a function set it and calls another function that sets it,
   the called function may incorrectly enable it.

   Use a new trace_tracing_disable() and tracer_tracing_enable() that
   uses a counter and can be nested. These use the ring buffer flags
   which are always checked making the disabling more consistent.

 - Save the trace clock in the persistent ring buffer

   Save what clock was used for tracing in the persistent ring buffer
   and set it back to that clock after a reboot.

 - Remove unused reference to a per CPU data pointer in mmiotrace
   functions

 - Remove unused buffer_page field from trace_array_cpu structure

 - Remove more strncpy() instances

 - Other minor clean ups and fixes

* tag 'trace-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (36 commits)
  tracing: Fix compilation warning on arm32
  tracing: Record trace_clock and recover when reboot
  tracing/sched: Use __string() instead of fixed lengths for task->comm
  tracepoint: Have tracepoints created with DECLARE_TRACE() have _tp suffix
  tracing: Cleanup upper_empty() in pid_list
  tracing: Allow the top level trace_marker to write into another instances
  tracing: Add a helper function to handle the dereference arg in verifier
  tracing: Remove unnecessary "goto out" that simply returns ret is trigger code
  tracing: Fix error handling in event_trigger_parse()
  tracing: Rename event_trigger_alloc() to trigger_data_alloc()
  tracing: Replace deprecated strncpy() with strscpy() for stack_trace_filter_buf
  tracing: Remove unused buffer_page field from trace_array_cpu structure
  tracing: Use atomic_inc_return() for updating "disabled" counter in irqsoff tracer
  tracing: Convert the per CPU "disabled" counter to local from atomic
  tracing: branch: Use trace_tracing_is_on_cpu() instead of "disabled" field
  ring-buffer: Add ring_buffer_record_is_on_cpu()
  tracing: Do not use per CPU array_buffer.data->disabled for cpumask
  ftrace: Do not disabled function graph based on "disabled" field
  tracing: kdb: Use tracer_tracing_on/off() instead of setting per CPU disabled
  tracing: Use tracer_tracing_disable() instead of "disabled" field for ftrace_dump_one()
  ...
2025-05-29 21:04:36 -07:00
Hendrik Hamerlinck
52092c1d50 docs: fix "incase" typo in coresight/panic.rst
Corrects a spelling mistake in Documentation/trace/coresight/panic.rst
where "incase" was used instead of "in case".

Signed-off-by: Hendrik Hamerlinck <hendrik.hamerlinck@hammernet.be>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250513110931.15072-1-hendrik.hamerlinck@hammernet.be>
2025-05-19 08:02:14 -06:00
Steven Rostedt
ac01fa73f5 tracepoint: Have tracepoints created with DECLARE_TRACE() have _tp suffix
Most tracepoints in the kernel are created with TRACE_EVENT(). The
TRACE_EVENT() macro (and DECLARE_EVENT_CLASS() and DEFINE_EVENT() where in
reality, TRACE_EVENT() is just a helper macro that calls those other two
macros), will create not only a tracepoint (the function trace_<event>()
used in the kernel), it also exposes the tracepoint to user space along
with defining what fields will be saved by that tracepoint.

There are a few places that tracepoints are created in the kernel that are
not exposed to userspace via tracefs. They can only be accessed from code
within the kernel. These tracepoints are created with DEFINE_TRACE()

Most of these tracepoints end with "_tp". This is useful as when the
developer sees that, they know that the tracepoint is for in-kernel only
(meaning it can only be accessed inside the kernel, either directly by the
kernel or indirectly via modules and BPF programs) and is not exposed to
user space.

Instead of making this only a process to add "_tp", enforce it by making
the DECLARE_TRACE() append the "_tp" suffix to the tracepoint. This
requires adding DECLARE_TRACE_EVENT() macros for the TRACE_EVENT() macro
to use that keeps the original name.

Link: https://lore.kernel.org/all/20250418083351.20a60e64@gandalf.local.home/

Cc: netdev <netdev@vger.kernel.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/20250510163730.092fad5b@gandalf.local.home
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-05-14 11:19:32 -04:00
Leo Yan
5161890f13 Documentation: coresight: Document AUX pause and resume
This adds description for AUX pause and resume.  It gives introduction
for what's AUX pause and resume and records usage examples.

Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250401180708.385396-8-leo.yan@arm.com
2025-05-14 11:56:17 +01:00
Steven Rostedt
7b382efd5e tracing: Allow the top level trace_marker to write into another instances
There are applications that have it hard coded to write into the top level
trace_marker instance (/sys/kernel/tracing/trace_marker). This can be
annoying if a profiler is using that instance for other work, or if it
needs all writes to go into a new instance.

A new option is created called "copy_trace_marker". By default, the top
level has this set, as that is the default buffer that writing into the
top level trace_marker file will go to. But now if an instance is created
and sets this option, all writes into the top level trace_marker will also
be written into that instance buffer just as if an application were to
write into the instance's trace_marker file.

If the top level instance disables this option, then writes to its own
trace_marker and trace_marker_raw files will not go into its buffer.

If no instance has this option set, then the write will return an error
and errno will contain ENODEV.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250508095639.39f84eda@gandalf.local.home
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-05-09 15:19:11 -04:00
Purva Yeshi
f0ba72e655 Documentation: trace: Refactor toctree
Refactor table of contents of kernel tracing subsystem docs to improve
clarity, structure, and organization:

- Reformat sections and add appropriate headings
- Improve section grouping and refine descriptions for each group
- Add docs intro paragraph

Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com>
Link: https://lore.kernel.org/r/20250318113230.24950-2-purvayeshi550@gmail.com
[Bagas: massage commit message and address reviews]
Co-developed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2025-04-21 10:37:13 -06:00
Purva Yeshi
33583537dd Documentation: trace: Reduce toctree depth
Reduce toctree depth from 2 to 1 so that only docs titles are listed
in the toctree.

Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com>
Link: https://lore.kernel.org/r/20250318113230.24950-1-purvayeshi550@gmail.com
[Bagas: massage commit message]
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2025-04-21 10:37:01 -06:00
Nam Cao
244132c4e5 tracing/timers: Rename the hrtimer_init event to hrtimer_setup
The function hrtimer_init() doesn't exist anymore. It was replaced by
hrtimer_setup().

Thus, rename the hrtimer_init trace event to hrtimer_setup to keep it
consistent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/cba84c3d853c5258aa3a262363a6eac08e2c7afc.1738746927.git.namcao@linutronix.de
2025-04-05 10:30:17 +02:00