diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2023-01-05 14:22:24 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-01-30 01:17:39 +0300 |
| commit | 3fcf19d592d5cb63eb209400b22055651e3c27d0 (patch) | |
| tree | 7709c204357d7a58896f73272698835ef7a1c170 /io_uring | |
| parent | 140102ae9a9f2f83f0592b98b3c5c6119d9a9b32 (diff) | |
| download | linux-3fcf19d592d5cb63eb209400b22055651e3c27d0.tar.xz | |
io_uring: parse check_cq out of wq waiting
We already avoid flushing overflows in io_cqring_wait_schedule() but
only return an error for the outer loop to handle it. Minimise it even
further by moving all ->check_cq parsing there.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9dfcec3121013f98208dbf79368d636d74e1231a.1672916894.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/io_uring.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 97b749203ba8..524ef5a2bb9c 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -2471,21 +2471,13 @@ static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx, ktime_t *timeout) { int ret; - unsigned long check_cq; + if (unlikely(READ_ONCE(ctx->check_cq))) + return 1; /* make sure we run task_work before checking for signals */ ret = io_run_task_work_sig(ctx); if (ret || io_should_wake(iowq)) return ret; - - check_cq = READ_ONCE(ctx->check_cq); - if (unlikely(check_cq)) { - /* let the caller flush overflows, retry */ - if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) - return 1; - if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) - return -EBADR; - } if (!schedule_hrtimeout(timeout, HRTIMER_MODE_ABS)) return -ETIME; @@ -2551,13 +2543,25 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, trace_io_uring_cqring_wait(ctx, min_events); do { - if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) { - finish_wait(&ctx->cq_wait, &iowq.wq); - io_cqring_do_overflow_flush(ctx); - } + unsigned long check_cq; + prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq, TASK_INTERRUPTIBLE); ret = io_cqring_wait_schedule(ctx, &iowq, &timeout); + + check_cq = READ_ONCE(ctx->check_cq); + if (unlikely(check_cq)) { + /* let the caller flush overflows, retry */ + if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) { + finish_wait(&ctx->cq_wait, &iowq.wq); + io_cqring_do_overflow_flush(ctx); + } + if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) { + ret = -EBADR; + break; + } + } + if (__io_cqring_events_user(ctx) >= min_events) break; cond_resched(); |