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| author | Pavel Begunkov <asml.silence@gmail.com> | 2024-04-10 02:26:54 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-08 16:26:47 +0100 |
| commit | 9f5a834715d04f32cb8a8d25fe329d67e7d16e46 (patch) | |
| tree | 28c151baae9813f2dfe1087dead3cc14ec5a90ee /io_uring | |
| parent | 79a727a9b88c5b390a4c54e5868473e83031d350 (diff) | |
| download | linux-9f5a834715d04f32cb8a8d25fe329d67e7d16e46.tar.gz linux-9f5a834715d04f32cb8a8d25fe329d67e7d16e46.tar.bz2 linux-9f5a834715d04f32cb8a8d25fe329d67e7d16e46.zip | |
io_uring: always lock __io_cqring_overflow_flush
Commit 8d09a88ef9d3cb7d21d45c39b7b7c31298d23998 upstream.
Conditional locking is never great, in case of
__io_cqring_overflow_flush(), which is a slow path, it's not justified.
Don't handle IOPOLL separately, always grab uring_lock for overflow
flushing.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/162947df299aa12693ac4b305dacedab32ec7976.1712708261.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/io_uring.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index f902b161f02c..92c1aa8f3501 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -593,6 +593,8 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) bool all_flushed; size_t cqe_size = sizeof(struct io_uring_cqe); + lockdep_assert_held(&ctx->uring_lock); + if (!force && __io_cqring_events(ctx) == ctx->cq_entries) return false; @@ -647,12 +649,9 @@ static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx) bool ret = true; if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) { - /* iopoll syncs against uring_lock, not completion_lock */ - if (ctx->flags & IORING_SETUP_IOPOLL) - mutex_lock(&ctx->uring_lock); + mutex_lock(&ctx->uring_lock); ret = __io_cqring_overflow_flush(ctx, false); - if (ctx->flags & IORING_SETUP_IOPOLL) - mutex_unlock(&ctx->uring_lock); + mutex_unlock(&ctx->uring_lock); } return ret; @@ -1405,6 +1404,8 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min) int ret = 0; unsigned long check_cq; + lockdep_assert_held(&ctx->uring_lock); + if (!io_allowed_run_tw(ctx)) return -EEXIST; |