diff options
| author | Jens Axboe <axboe@kernel.dk> | 2019-04-13 17:28:55 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-04-14 03:08:22 +0200 |
| commit | 917257daa0fea7a007102691c0e27d9216a96768 (patch) | |
| tree | b9eb940786c1bc428f79025919777848b2fd6e54 /fs | |
| parent | io_uring: park SQPOLL thread if it's percpu (diff) | |
| download | linux-917257daa0fea7a007102691c0e27d9216a96768.tar.xz linux-917257daa0fea7a007102691c0e27d9216a96768.zip | |
io_uring: only test SQPOLL cpu after we've verified it
We currently call cpu_possible() even if we don't use the CPU. Move the
test under the SQ_AFF branch, which is the only place where we'll use
the value. Do the cpu_possible() test AFTER we've limited it to a max
of NR_CPUS. This avoids triggering the following warning:
WARNING: CPU: 1 PID: 7600 at include/linux/cpumask.h:121 cpu_max_bits_warn
if CONFIG_DEBUG_PER_CPU_MAPS is enabled.
While in there, also move the SQ thread idle period assignment inside
SETUP_SQPOLL, as we don't use it otherwise either.
Reported-by: syzbot+cd714a07c6de2bc34293@syzkaller.appspotmail.com
Fixes: 6c271ce2f1d5 ("io_uring: add submission polling")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/io_uring.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index e5008c1b82be..24355e0c47f0 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2241,10 +2241,6 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx, mmgrab(current->mm); ctx->sqo_mm = current->mm; - ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle); - if (!ctx->sq_thread_idle) - ctx->sq_thread_idle = HZ; - ret = -EINVAL; if (!cpu_possible(p->sq_thread_cpu)) goto err; @@ -2254,10 +2250,18 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx, if (!capable(CAP_SYS_ADMIN)) goto err; + ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle); + if (!ctx->sq_thread_idle) + ctx->sq_thread_idle = HZ; + if (p->flags & IORING_SETUP_SQ_AFF) { int cpu; cpu = array_index_nospec(p->sq_thread_cpu, NR_CPUS); + ret = -EINVAL; + if (!cpu_possible(p->sq_thread_cpu)) + goto err; + ctx->sqo_thread = kthread_create_on_cpu(io_sq_thread, ctx, cpu, "io_uring-sq"); |