diff options
| author | Jens Axboe <axboe@kernel.dk> | 2026-02-03 09:56:55 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-02-03 10:58:32 -0700 |
| commit | 38cfdd9dd279473a73814df9fd7e6e716951d361 (patch) | |
| tree | e60a82275805c20883f8cc2843728610c4a30c8e | |
| parent | b1dfe4e0fcef0cc01233a70ec8fd95b900024a5a (diff) | |
io_uring/fdinfo: be a bit nicer when looping a lot of SQEs/CQEs
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>
| -rw-r--r-- | io_uring/fdinfo.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c index 4f12e98b22c3..80178b69e05a 100644 --- a/io_uring/fdinfo.c +++ b/io_uring/fdinfo.c @@ -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_tail = READ_ONCE(r->cq.tail); unsigned int sq_shift = 0; - unsigned int sq_entries; + unsigned int cq_entries, sq_entries; int sq_pid = -1, sq_cpu = -1; u64 sq_total_time = 0, sq_work_time = 0; 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"); + cond_resched(); } 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; 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]); seq_printf(m, "\n"); cq_head++; - if (cqe32) + if (cqe32) { cq_head++; + i++; + } + cond_resched(); } if (ctx->flags & IORING_SETUP_SQPOLL) { |