linux/include
Frederic Weisbecker f400565faa perf: Remove too early and redundant CPU hotplug handling
The CPU hotplug handlers are called twice: at prepare and online stage.

Their role is to:

1) Enable/disable a CPU context. This is irrelevant and even buggy at
   the prepare stage because the CPU is still offline. On early
   secondary CPU up, creating an event attached to that CPU might
   silently fail because the CPU context is observed as online but the
   context installation's IPI failure is ignored.

2) Update the scope cpumasks and re-migrate the events accordingly in
   the CPU down case. This is irrelevant at the prepare stage.

3) Remove the events attached to the context of the offlining CPU. It
   even uses an (unnecessary) IPI for it. This is also irrelevant at the
   prepare stage.

Also none of the *_PREPARE and *_STARTING architecture perf related CPU
hotplug callbacks rely on CPUHP_PERF_PREPARE.

CPUHP_AP_PERF_ONLINE is enough and the right place to perform the work.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20250424161128.29176-4-frederic@kernel.org
2025-05-08 21:50:19 +02:00
..
acpi gcc-15: acpi: sprinkle random '__nonstring' crumbles around 2025-04-20 11:57:54 -07:00
asm-generic RISC-V Patches for the 6.15 Merge Window, Part 1 2025-04-04 09:49:17 -07:00
clocksource
crypto crypto: ahash - Disable request chaining 2025-04-12 09:33:09 +08:00
cxl cxl for v6.15 2025-04-02 20:04:43 -07:00
drm Short summary of fixes pull: 2025-04-18 08:38:29 +10:00
dt-bindings Char/Misc/IIO driver updates for 6.15-rc1 2025-04-01 11:26:08 -07:00
hyperv x86/hyperv: Add comments about hv_vpset and var size hypercall input args 2025-03-21 18:24:22 +00:00
keys
kunit kunit: Spelling s/slowm/slow/ 2025-04-08 14:57:24 -06:00
kvm Merge branch 'kvm-arm64/pmu-fixes' into kvmarm/next 2025-03-19 14:54:52 -07:00
linux perf: Remove too early and redundant CPU hotplug handling 2025-05-08 21:50:19 +02:00
math-emu
media
memory
misc cxl: Remove driver 2025-03-16 22:04:27 +11:00
net net: fib_rules: Fix iif / oif matching on L3 master device 2025-04-15 17:54:56 -07:00
pcmcia
ras
rdma RDMA/mlx5: Fix compilation warning when USER_ACCESS isn't set 2025-04-07 15:14:34 -03:00
rv
scsi
soc soc: driver updates for 6.15, part 1 2025-03-27 09:05:55 -07:00
sound soundwire updates for 6.15 2025-04-01 12:43:13 -07:00
target
trace tracing/timers: Rename the hrtimer_init event to hrtimer_setup 2025-04-05 10:30:17 +02:00
uapi drm fixes for 6.15-rc3 2025-04-19 09:31:21 -07:00
ufs scsi: ufs: core: Add device level exception support 2025-04-03 10:54:31 -04:00
vdso vdso: Address variable shadowing in macros 2025-04-10 11:07:10 +02:00
video
xen xen/mcelog: Add __nonstring annotations for unterminated strings 2025-03-14 11:15:16 +01:00
Kbuild