From: Hao Xu <howeyxu@xxxxxxxxxxx>
From: Hao Xu <howeyxu@xxxxxxxxxxx>
Use per list lock for cancel_hash, this removes some completion lock
invocation and remove contension between different cancel_hash entries
Signed-off-by: Hao Xu <howeyxu@xxxxxxxxxxx>
---
io_uring/cancel.c | 12 ++++++++++--
io_uring/cancel.h | 1 +
io_uring/io_uring.c | 9 +++++++++
io_uring/io_uring_types.h | 1 +
io_uring/poll.c | 30 ++++++++++++++++--------------
5 files changed, 37 insertions(+), 16 deletions(-)
diff --git a/io_uring/cancel.c b/io_uring/cancel.c
index 83cceb52d82d..0b1aa3ab7664 100644
--- a/io_uring/cancel.c
+++ b/io_uring/cancel.c
@@ -93,14 +93,14 @@ int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd)
if (!ret)
return 0;
- spin_lock(&ctx->completion_lock);
ret = io_poll_cancel(ctx, cd);
if (ret != -ENOENT)
goto out;
+ spin_lock(&ctx->completion_lock);
if (!(cd->flags & IORING_ASYNC_CANCEL_FD))
ret = io_timeout_cancel(ctx, cd);
-out:
spin_unlock(&ctx->completion_lock);
+out:
return ret;
}
@@ -192,3 +192,11 @@ int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
io_req_set_res(req, ret, 0);
return IOU_OK;
}
+
+inline void init_cancel_hash_locks(spinlock_t *cancel_hash_locks, unsigned size)
+{
+ int i;
+
+ for (i = 0; i < size; i++)
+ spin_lock_init(&cancel_hash_locks[i]);
+}
diff --git a/io_uring/cancel.h b/io_uring/cancel.h
index 4f35d8696325..fdec2595797e 100644
--- a/io_uring/cancel.h
+++ b/io_uring/cancel.h
@@ -4,3 +4,4 @@ int io_async_cancel_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags);
int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd);
+inline void init_cancel_hash_locks(spinlock_t *cancel_hash_locks, unsigned size);
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index f31d3446dcbf..6eaa27aea197 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -706,7 +706,14 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
GFP_KERNEL);
if (!ctx->cancel_hash)
goto err;
+ ctx->cancel_hash_locks =
+ kmalloc((1U << hash_bits) * sizeof(spinlock_t),
+ GFP_KERNEL);
+ if (!ctx->cancel_hash_locks)
+ goto err;
+
__hash_init(ctx->cancel_hash, 1U << hash_bits);
+ init_cancel_hash_locks(ctx->cancel_hash_locks, 1U << hash_bits);
ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
if (!ctx->dummy_ubuf)
@@ -749,6 +756,7 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
err:
kfree(ctx->dummy_ubuf);
kfree(ctx->cancel_hash);
+ kfree(ctx->cancel_hash_locks);
kfree(ctx->io_bl);
xa_destroy(&ctx->io_bl_xa);
kfree(ctx);
@@ -3045,6 +3053,7 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
if (ctx->hash_map)
io_wq_put_hash(ctx->hash_map);
kfree(ctx->cancel_hash);
+ kfree(ctx->cancel_hash_locks);
kfree(ctx->dummy_ubuf);
kfree(ctx->io_bl);
xa_destroy(&ctx->io_bl_xa);
diff --git a/io_uring/io_uring_types.h b/io_uring/io_uring_types.h
index 7c22cf35a7e2..4619a46f7ecd 100644
--- a/io_uring/io_uring_types.h
+++ b/io_uring/io_uring_types.h
@@ -231,6 +231,7 @@ struct io_ring_ctx {
*/
struct io_wq_work_list iopoll_list;
struct hlist_head *cancel_hash;
+ spinlock_t *cancel_hash_locks;
unsigned cancel_hash_bits;
bool poll_multi_queue;
diff --git a/io_uring/poll.c b/io_uring/poll.c
index c8982c5ef0fa..e1b6dd282860 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -73,10 +73,11 @@ static struct io_poll *io_poll_get_single(struct io_kiocb *req)
static void io_poll_req_insert(struct io_kiocb *req)
{
struct io_ring_ctx *ctx = req->ctx;
- struct hlist_head *list;
+ u32 index = hash_long(req->cqe.user_data, ctx->cancel_hash_bits);
- list = &ctx->cancel_hash[hash_long(req->cqe.user_data, ctx->cancel_hash_bits)];
- hlist_add_head(&req->hash_node, list);
+ spin_lock(&ctx->cancel_hash_locks[index]);
+ hlist_add_head(&req->hash_node, &ctx->cancel_hash[index]);
+ spin_unlock(&ctx->cancel_hash_locks[index]);
}
static void io_init_poll_iocb(struct io_poll *poll, __poll_t events,
@@ -439,9 +440,7 @@ static int __io_arm_poll_handler(struct io_kiocb *req,
return 0;
}
- spin_lock(&ctx->completion_lock);
io_poll_req_insert(req);
- spin_unlock(&ctx->completion_lock);
if (mask && (poll->events & EPOLLET)) {
/* can't multishot if failed, just queue the event we've got */
@@ -538,10 +537,10 @@ __cold bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
bool found = false;
int i;
- spin_lock(&ctx->completion_lock);
for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
struct hlist_head *list;
+ spin_lock(&ctx->cancel_hash_locks[i]);
list = &ctx->cancel_hash[i];
hlist_for_each_entry_safe(req, tmp, list, hash_node) {
if (io_match_task_safe(req, tsk, cancel_all)) {
@@ -550,19 +549,19 @@ __cold bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
found = true;
}
}
+ spin_unlock(&ctx->cancel_hash_locks[i]);
}
- spin_unlock(&ctx->completion_lock);
return found;
}
static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, bool poll_only,
struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
{
struct hlist_head *list;
struct io_kiocb *req;
u32 index = hash_long(cd->data, ctx->cancel_hash_bits);
+ spin_lock(&ctx->cancel_hash_locks[index]);
list = &ctx->cancel_hash[index];
hlist_for_each_entry(req, list, hash_node) {
if (cd->data != req->cqe.user_data)
@@ -574,15 +573,16 @@ static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, bool poll_only,
continue;
req->work.cancel_seq = cd->seq;
}
+ spin_unlock(&ctx->cancel_hash_locks[index]);
cd->flags = index;
return req;
}
+ spin_unlock(&ctx->cancel_hash_locks[index]);
return NULL;
}
static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
{
struct io_kiocb *req;
int i;
@@ -590,6 +590,7 @@ static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
struct hlist_head *list;
+ spin_lock(&ctx->cancel_hash_locks[i]);
list = &ctx->cancel_hash[i];
hlist_for_each_entry(req, list, hash_node) {
if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
@@ -598,24 +599,28 @@ static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
if (cd->seq == req->work.cancel_seq)
continue;
req->work.cancel_seq = cd->seq;
+ spin_unlock(&ctx->cancel_hash_locks[i]);
return req;
}
+ spin_unlock(&ctx->cancel_hash_locks[i]);
}
return NULL;
}
static bool io_poll_disarm(struct io_kiocb *req, u32 index)
- __must_hold(&ctx->completion_lock)
{
+ struct io_ring_ctx *ctx = req->ctx;
+
if (!io_poll_get_ownership(req))
return false;
io_poll_remove_entries(req);
+ spin_lock(&ctx->cancel_hash_locks[index]);
hash_del(&req->hash_node);
+ spin_unlock(&ctx->cancel_hash_locks[index]);
return true;
}
int io_poll_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
- __must_hold(&ctx->completion_lock)
{
struct io_kiocb *req;
@@ -724,14 +729,11 @@ int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
int ret2, ret = 0;
bool locked;
- spin_lock(&ctx->completion_lock);
preq = io_poll_find(ctx, true, &cd);
if (!preq || !io_poll_disarm(preq, cd.flags)) {
- spin_unlock(&ctx->completion_lock);
ret = preq ? -EALREADY : -ENOENT;
goto out;
}
- spin_unlock(&ctx->completion_lock);
if (poll_update->update_events || poll_update->update_user_data) {
/* only mask one event flags, keep behavior flags */
--
2.25.1
