From d60aa65ba221f038404b98d8484f562f72bb807b Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Mon, 4 Oct 2021 20:02:52 +0100
Subject: [PATCH] io_uring: merge CQ and poll waitqueues
Git-commit: d60aa65ba221f038404b98d8484f562f72bb807b
Patch-mainline: v5.16-rc1
References: bsc#1205205
->cq_wait and ->poll_wait and waken up in the same manner, use a single
waitqueue for both of them. CQ waiters are queued exclusively, so wake
up should first go over all pollers and that's what we need.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/00fe603e50000365774cf8435ef5fe03f049c1c9.1633373302.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
fs/io_uring.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index af2cbe633345..c9e6f4b68718 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -394,7 +394,6 @@ struct io_ring_ctx {
unsigned cached_cq_tail;
unsigned cq_entries;
struct eventfd_ctx *cq_ev_fd;
- struct wait_queue_head poll_wait;
struct wait_queue_head cq_wait;
unsigned cq_extra;
atomic_t cq_timeouts;
@@ -1300,7 +1299,6 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
ctx->flags = p->flags;
init_waitqueue_head(&ctx->sqo_sq_wait);
INIT_LIST_HEAD(&ctx->sqd_list);
- init_waitqueue_head(&ctx->poll_wait);
INIT_LIST_HEAD(&ctx->cq_overflow_list);
init_completion(&ctx->ref_comp);
xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
@@ -1621,8 +1619,6 @@ static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
wake_up_all(&ctx->cq_wait);
if (io_should_trigger_evfd(ctx))
eventfd_signal(ctx->cq_ev_fd, 1);
- if (waitqueue_active(&ctx->poll_wait))
- wake_up_interruptible(&ctx->poll_wait);
}
static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
@@ -1636,8 +1632,6 @@ static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
}
if (io_should_trigger_evfd(ctx))
eventfd_signal(ctx->cq_ev_fd, 1);
- if (waitqueue_active(&ctx->poll_wait))
- wake_up_interruptible(&ctx->poll_wait);
}
/* Returns true if there are no backlogged entries after the flush */
@@ -9253,7 +9247,7 @@ static __poll_t io_uring_poll(struct file *file, poll_table *wait)
struct io_ring_ctx *ctx = file->private_data;
__poll_t mask = 0;
- poll_wait(file, &ctx->poll_wait, wait);
+ poll_wait(file, &ctx->cq_wait, wait);
/*
* synchronizes with barrier from wq_has_sleeper call in
* io_commit_cqring
--
2.35.3