archives/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-03-08 01:24:47 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

io_uring/fdinfo: be a bit nicer when looping a lot of SQEs/CQEs

Browse source 
Add cond_resched() in those dump loops, just in case a lot of entries
are being dumped. And detect invalid CQ ring head/tail entries, to avoid
iterating more than what is necessary. Generally not an issue, but can be
if things like KASAN or other debugging metrics are enabled.

Reported-by: 是参差 <shicenci@gmail.com>
Link: https://lore.kernel.org/all/PS1PPF7E1D7501FE5631002D242DD89403FAB9BA@PS1PPF7E1D7501F.apcprd02.prod.outlook.com/
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2026-02-03 09:56:55 -07:00
parent b1dfe4e0fc
commit 38cfdd9dd2
1 changed files with 8 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

11
io_uring/fdinfo.c
View file

@ -67,7 +67,7 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
unsigned int cq_head = READ_ONCE(r->cq.head); unsigned int cq_head = READ_ONCE(r->cq.head);
unsigned int cq_tail = READ_ONCE(r->cq.tail); unsigned int cq_tail = READ_ONCE(r->cq.tail);
unsigned int sq_shift = 0; unsigned int sq_shift = 0;
unsigned int sq_entries; unsigned int cq_entries, sq_entries;
int sq_pid = -1, sq_cpu = -1; int sq_pid = -1, sq_cpu = -1;
u64 sq_total_time = 0, sq_work_time = 0; u64 sq_total_time = 0, sq_work_time = 0;
unsigned int i; unsigned int i;
@ -146,9 +146,11 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
} }
} }
seq_printf(m, "\n"); seq_printf(m, "\n");
cond_resched();
} }
seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head); seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
while (cq_head < cq_tail) { cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
for (i = 0; i < cq_entries; i++) {
struct io_uring_cqe *cqe; struct io_uring_cqe *cqe;
bool cqe32 = false; bool cqe32 = false;
@ -163,8 +165,11 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
cqe->big_cqe[0], cqe->big_cqe[1]); cqe->big_cqe[0], cqe->big_cqe[1]);
seq_printf(m, "\n"); seq_printf(m, "\n");
cq_head++; cq_head++;
if (cqe32) if (cqe32) {
cq_head++; cq_head++;
i++;
}
cond_resched();
} }
if (ctx->flags & IORING_SETUP_SQPOLL) { if (ctx->flags & IORING_SETUP_SQPOLL) {