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| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-07-12 22:52:40 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-07-25 02:41:06 +0200 |
| commit | e58d498e81baa9fd8acf5132d8b2d4f829361f6b (patch) | |
| tree | addc514ac82d4325ee3fa2dc2f0e7b0aa9ca97bb /io_uring | |
| parent | io_uring: cache struct io_notif (diff) | |
| download | linux-e58d498e81baa9fd8acf5132d8b2d4f829361f6b.tar.xz linux-e58d498e81baa9fd8acf5132d8b2d4f829361f6b.zip | |
io_uring: complete notifiers in tw
We need a task context to post CQEs but using wq is too expensive.
Try to complete notifiers using task_work and fall back to wq if fails.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/089799ab665b10b78fdc614ae6d59fa7ef0d5f91.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/notif.c | 22 | ||||
| -rw-r--r-- | io_uring/notif.h | 3 |
2 files changed, 22 insertions, 3 deletions
diff --git a/io_uring/notif.c b/io_uring/notif.c index b257db2120b4..aec74f88fc33 100644 --- a/io_uring/notif.c +++ b/io_uring/notif.c @@ -13,6 +13,11 @@ static void __io_notif_complete_tw(struct callback_head *cb) struct io_notif *notif = container_of(cb, struct io_notif, task_work); struct io_ring_ctx *ctx = notif->ctx; + if (likely(notif->task)) { + io_put_task(notif->task, 1); + notif->task = NULL; + } + io_cq_lock(ctx); io_fill_cqe_aux(ctx, notif->tag, 0, notif->seq, true); @@ -43,6 +48,14 @@ static void io_uring_tx_zerocopy_callback(struct sk_buff *skb, if (!refcount_dec_and_test(&uarg->refcnt)) return; + + if (likely(notif->task)) { + init_task_work(¬if->task_work, __io_notif_complete_tw); + if (likely(!task_work_add(notif->task, ¬if->task_work, + TWA_SIGNAL))) + return; + } + INIT_WORK(¬if->commit_work, io_notif_complete_wq); queue_work(system_unbound_wq, ¬if->commit_work); } @@ -134,12 +147,15 @@ __cold int io_notif_unregister(struct io_ring_ctx *ctx) for (i = 0; i < ctx->nr_notif_slots; i++) { struct io_notif_slot *slot = &ctx->notif_slots[i]; - if (slot->notif) - io_notif_slot_flush(slot); + if (!slot->notif) + continue; + if (WARN_ON_ONCE(slot->notif->task)) + slot->notif->task = NULL; + io_notif_slot_flush(slot); } kvfree(ctx->notif_slots); ctx->notif_slots = NULL; ctx->nr_notif_slots = 0; return 0; -}
\ No newline at end of file +} diff --git a/io_uring/notif.h b/io_uring/notif.h index b23c9c0515bb..23ca7620fff9 100644 --- a/io_uring/notif.h +++ b/io_uring/notif.h @@ -11,6 +11,9 @@ struct io_notif { struct ubuf_info uarg; struct io_ring_ctx *ctx; + /* complete via tw if ->task is non-NULL, fallback to wq otherwise */ + struct task_struct *task; + /* cqe->user_data, io_notif_slot::tag if not overridden */ u64 tag; /* see struct io_notif_slot::seq */ |