diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-10-06 23:42:33 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-10-13 01:30:56 +0300 |
| commit | 44f87745d5f24a3cdf0548bf1d84fbb7316ce229 (patch) | |
| tree | c4de76d2b6b2ab7c696c8cc31cc87b2c088e197d /io_uring | |
| parent | fc86f9d3bb4904117eea70347d323fde34a47c79 (diff) | |
| download | linux-44f87745d5f24a3cdf0548bf1d84fbb7316ce229.tar.xz | |
io_uring: optimise locking for local tw with submit_wait
Running local task_work requires taking uring_lock, for submit + wait we
can try to run them right after submit while we still hold the lock and
save one lock/unlokc pair. The optimisation was implemented in the first
local tw patches but got dropped for simplicity.
Suggested-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/281fc79d98b5d91fe4778c5137a17a2ab4693e5c.1665088876.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 | 12 | ||||
| -rw-r--r-- | io_uring/io_uring.h | 7 |
2 files changed, 17 insertions, 2 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 12870cd7cb07..de08d9902b30 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3227,8 +3227,16 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, mutex_unlock(&ctx->uring_lock); goto out; } - if ((flags & IORING_ENTER_GETEVENTS) && ctx->syscall_iopoll) - goto iopoll_locked; + if (flags & IORING_ENTER_GETEVENTS) { + if (ctx->syscall_iopoll) + goto iopoll_locked; + /* + * Ignore errors, we'll soon call io_cqring_wait() and + * it should handle ownership problems if any. + */ + if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) + (void)io_run_local_work_locked(ctx); + } mutex_unlock(&ctx->uring_lock); } diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h index 47d4cad1e9c4..ef77d2aa3172 100644 --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -275,6 +275,13 @@ static inline int io_run_task_work_ctx(struct io_ring_ctx *ctx) return ret; } +static inline int io_run_local_work_locked(struct io_ring_ctx *ctx) +{ + if (llist_empty(&ctx->work_llist)) + return 0; + return __io_run_local_work(ctx, true); +} + static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked) { if (!*locked) { |