[PATCH for-next 0/5] 5.15 cleanups and optimisations

[PATCH for-next 0/5] 5.15 cleanups and optimisations

[Pavel Begunkov]

Some improvements after killing refcounting, and other cleanups.

With 2/2 with will be only tracking reqs with
file->f_op == &io_uring_fops, which is nice.

Pavel Begunkov (5):
  io_uring: optimise iowq refcounting
  io_uring: don't inflight-track linked timeouts
  io_uring: optimise initial ltimeout refcounting
  io_uring: kill not necessary resubmit switch
  io_uring: deduplicate cancellation code

 fs/io_uring.c | 82 ++++++++++++++++++++++++---------------------------
 1 file changed, 38 insertions(+), 44 deletions(-)

-- 
2.32.0

[PATCH 1/5] io_uring: optimise iowq refcounting

[Pavel Begunkov]

If a requests is forwarded into io-wq, there is a good chance it hasn't
been refcounted yet and we can save one req_ref_get() by setting the
refcount number to the right value directly.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 51c4166f68b5..0d9a443d4987 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
 	atomic_inc(&req->refs);
 }
 
-static inline void io_req_refcount(struct io_kiocb *req)
+static inline void __io_req_refcount(struct io_kiocb *req, int nr)
 {
 	if (!(req->flags & REQ_F_REFCOUNT)) {
 		req->flags |= REQ_F_REFCOUNT;
-		atomic_set(&req->refs, 1);
+		atomic_set(&req->refs, nr);
 	}
 }
 
+static inline void io_req_refcount(struct io_kiocb *req)
+{
+	__io_req_refcount(req, 1);
+}
+
 static inline void io_req_set_rsrc_node(struct io_kiocb *req)
 {
 	struct io_ring_ctx *ctx = req->ctx;
@@ -6311,9 +6316,11 @@ static void io_wq_submit_work(struct io_wq_work *work)
 	struct io_kiocb *timeout;
 	int ret = 0;
 
-	io_req_refcount(req);
-	/* will be dropped by ->io_free_work() after returning to io-wq */
-	req_ref_get(req);
+	/* one will be dropped by ->io_free_work() after returning to io-wq */
+	if (!(req->flags & REQ_F_REFCOUNT))
+		__io_req_refcount(req, 2);
+	else
+		req_ref_get(req);
 
 	timeout = io_prep_linked_timeout(req);
 	if (timeout)
-- 
2.32.0

[PATCH 2/5] io_uring: don't inflight-track linked timeouts

[Pavel Begunkov]

Tracking linked timeouts as infligh was needed to make sure that io-wq
is not destroyed by io_uring_cancel_generic() racing with
io_async_cancel_one() accessing it. Now, cancellations issued by linked
timeouts are done in the task context, so it's already synchronised.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 0d9a443d4987..d572a831cf85 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5699,8 +5699,6 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 
 	data->mode = io_translate_timeout_mode(flags);
 	hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
-	if (is_timeout_link)
-		io_req_track_inflight(req);
 	return 0;
 }
 
-- 
2.32.0

[PATCH 3/5] io_uring: optimise initial ltimeout refcounting

[Pavel Begunkov]

Linked timeouts are never refcounted when it comes to the first call to
__io_prep_linked_timeout(), so save an io_ref_get() and set the desired
value directly.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index d572a831cf85..37b5516b63c8 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1310,8 +1310,7 @@ static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
 
 	/* linked timeouts should have two refs once prep'ed */
 	io_req_refcount(req);
-	io_req_refcount(nxt);
-	req_ref_get(nxt);
+	__io_req_refcount(nxt, 2);
 
 	nxt->timeout.head = req;
 	nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
-- 
2.32.0

[PATCH 4/5] io_uring: kill not necessary resubmit switch

[Pavel Begunkov]

773af69121ecc ("io_uring: always reissue from task_work context") makes
all resubmission to be made from task_work, so we don't need that hack
with resubmit/not-resubmit switch anymore.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 37b5516b63c8..c16d172ca37f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2291,7 +2291,7 @@ static inline bool io_run_task_work(void)
  * Find and free completed poll iocbs
  */
 static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
-			       struct list_head *done, bool resubmit)
+			       struct list_head *done)
 {
 	struct req_batch rb;
 	struct io_kiocb *req;
@@ -2306,7 +2306,7 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
 		req = list_first_entry(done, struct io_kiocb, inflight_entry);
 		list_del(&req->inflight_entry);
 
-		if (READ_ONCE(req->result) == -EAGAIN && resubmit &&
+		if (READ_ONCE(req->result) == -EAGAIN &&
 		    !(req->flags & REQ_F_DONT_REISSUE)) {
 			req->iopoll_completed = 0;
 			io_req_task_queue_reissue(req);
@@ -2329,7 +2329,7 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
 }
 
 static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
-			long min, bool resubmit)
+			long min)
 {
 	struct io_kiocb *req, *tmp;
 	LIST_HEAD(done);
@@ -2369,7 +2369,7 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
 	}
 
 	if (!list_empty(&done))
-		io_iopoll_complete(ctx, nr_events, &done, resubmit);
+		io_iopoll_complete(ctx, nr_events, &done);
 
 	return 0;
 }
@@ -2387,7 +2387,7 @@ static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
 	while (!list_empty(&ctx->iopoll_list)) {
 		unsigned int nr_events = 0;
 
-		io_do_iopoll(ctx, &nr_events, 0, false);
+		io_do_iopoll(ctx, &nr_events, 0);
 
 		/* let it sleep and repeat later if can't complete a request */
 		if (nr_events == 0)
@@ -2449,7 +2449,7 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
 			    list_empty(&ctx->iopoll_list))
 				break;
 		}
-		ret = io_do_iopoll(ctx, &nr_events, min, true);
+		ret = io_do_iopoll(ctx, &nr_events, min);
 	} while (!ret && nr_events < min && !need_resched());
 out:
 	mutex_unlock(&ctx->uring_lock);
@@ -6855,7 +6855,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
 
 		mutex_lock(&ctx->uring_lock);
 		if (!list_empty(&ctx->iopoll_list))
-			io_do_iopoll(ctx, &nr_events, 0, true);
+			io_do_iopoll(ctx, &nr_events, 0);
 
 		/*
 		 * Don't submit if refs are dying, good for io_uring_register(),
-- 
2.32.0

[PATCH 5/5] io_uring: deduplicate cancellations

[Pavel Begunkov]

IORING_OP_ASYNC_CANCEL and IORING_OP_LINK_TIMEOUT have enough of
overlap, so extract a helper for request cancellation and use in both.
Also, removes some amount of ugliness because of success_ret.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 46 ++++++++++++++++++----------------------------
 1 file changed, 18 insertions(+), 28 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index c16d172ca37f..5560620968c9 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5790,32 +5790,24 @@ static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
 	return ret;
 }
 
-static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
-				     struct io_kiocb *req, __u64 sqe_addr,
-				     int success_ret)
+static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
+	__acquires(&req->ctx->completion_lock)
 {
+	struct io_ring_ctx *ctx = req->ctx;
 	int ret;
 
+	WARN_ON_ONCE(req->task != current);
+
 	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
 	spin_lock(&ctx->completion_lock);
 	if (ret != -ENOENT)
-		goto done;
+		return ret;
 	spin_lock_irq(&ctx->timeout_lock);
 	ret = io_timeout_cancel(ctx, sqe_addr);
 	spin_unlock_irq(&ctx->timeout_lock);
 	if (ret != -ENOENT)
-		goto done;
-	ret = io_poll_cancel(ctx, sqe_addr, false);
-done:
-	if (!ret)
-		ret = success_ret;
-	io_cqring_fill_event(ctx, req->user_data, ret, 0);
-	io_commit_cqring(ctx);
-	spin_unlock(&ctx->completion_lock);
-	io_cqring_ev_posted(ctx);
-
-	if (ret < 0)
-		req_set_fail(req);
+		return ret;
+	return io_poll_cancel(ctx, sqe_addr, false);
 }
 
 static int io_async_cancel_prep(struct io_kiocb *req,
@@ -5839,17 +5831,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
 	struct io_tctx_node *node;
 	int ret;
 
-	/* tasks should wait for their io-wq threads, so safe w/o sync */
-	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
-	spin_lock(&ctx->completion_lock);
-	if (ret != -ENOENT)
-		goto done;
-	spin_lock_irq(&ctx->timeout_lock);
-	ret = io_timeout_cancel(ctx, sqe_addr);
-	spin_unlock_irq(&ctx->timeout_lock);
-	if (ret != -ENOENT)
-		goto done;
-	ret = io_poll_cancel(ctx, sqe_addr, false);
+	ret = io_try_cancel_userdata(req, sqe_addr);
 	if (ret != -ENOENT)
 		goto done;
 	spin_unlock(&ctx->completion_lock);
@@ -6416,9 +6398,17 @@ static void io_req_task_link_timeout(struct io_kiocb *req)
 {
 	struct io_kiocb *prev = req->timeout.prev;
 	struct io_ring_ctx *ctx = req->ctx;
+	int ret;
 
 	if (prev) {
-		io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
+		ret = io_try_cancel_userdata(req, prev->user_data);
+		if (!ret)
+			ret = -ETIME;
+		io_cqring_fill_event(ctx, req->user_data, ret, 0);
+		io_commit_cqring(ctx);
+		spin_unlock(&ctx->completion_lock);
+		io_cqring_ev_posted(ctx);
+
 		io_put_req(prev);
 		io_put_req(req);
 	} else {
-- 
2.32.0

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Jens Axboe]

On 8/14/21 10:26 AM, Pavel Begunkov wrote:
> If a requests is forwarded into io-wq, there is a good chance it hasn't
> been refcounted yet and we can save one req_ref_get() by setting the
> refcount number to the right value directly.

Not sure this really matters, but can't hurt either. But...

> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>  	atomic_inc(&req->refs);
>  }
>  
> -static inline void io_req_refcount(struct io_kiocb *req)
> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>  {
>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>  		req->flags |= REQ_F_REFCOUNT;
> -		atomic_set(&req->refs, 1);
> +		atomic_set(&req->refs, nr);
>  	}
>  }
>  
> +static inline void io_req_refcount(struct io_kiocb *req)
> +{
> +	__io_req_refcount(req, 1);
> +}
> +

I really think these should be io_req_set_refcount() or something like
that, making it clear that we're actively setting/manipulating the ref
count.

-- 
Jens Axboe

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Pavel Begunkov]

On 8/14/21 8:13 PM, Jens Axboe wrote:
> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>> been refcounted yet and we can save one req_ref_get() by setting the
>> refcount number to the right value directly.
> 
> Not sure this really matters, but can't hurt either. But...

The refcount patches made this one atomic worse, and I just prefer
to not regress, even if slightly

>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>  	atomic_inc(&req->refs);
>>  }
>>  
>> -static inline void io_req_refcount(struct io_kiocb *req)
>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>  {
>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>  		req->flags |= REQ_F_REFCOUNT;
>> -		atomic_set(&req->refs, 1);
>> +		atomic_set(&req->refs, nr);
>>  	}
>>  }
>>  
>> +static inline void io_req_refcount(struct io_kiocb *req)
>> +{
>> +	__io_req_refcount(req, 1);
>> +}
>> +
> 
> I really think these should be io_req_set_refcount() or something like
> that, making it clear that we're actively setting/manipulating the ref
> count.

Agree. A separate patch, maybe?

-- 
Pavel Begunkov

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Pavel Begunkov]

On 8/14/21 8:31 PM, Pavel Begunkov wrote:
> On 8/14/21 8:13 PM, Jens Axboe wrote:
>> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>>> been refcounted yet and we can save one req_ref_get() by setting the
>>> refcount number to the right value directly.
>>
>> Not sure this really matters, but can't hurt either. But...
> 
> The refcount patches made this one atomic worse, and I just prefer
> to not regress, even if slightly
> 
>>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>>  	atomic_inc(&req->refs);
>>>  }
>>>  
>>> -static inline void io_req_refcount(struct io_kiocb *req)
>>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>>  {
>>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>>  		req->flags |= REQ_F_REFCOUNT;
>>> -		atomic_set(&req->refs, 1);
>>> +		atomic_set(&req->refs, nr);
>>>  	}
>>>  }
>>>  
>>> +static inline void io_req_refcount(struct io_kiocb *req)
>>> +{
>>> +	__io_req_refcount(req, 1);
>>> +}
>>> +
>>
>> I really think these should be io_req_set_refcount() or something like
>> that, making it clear that we're actively setting/manipulating the ref
>> count.
> 
> Agree. A separate patch, maybe?

I mean it just would be a bit easier for me, instead of rebasing
this series and not yet sent patches.

-- 
Pavel Begunkov

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Jens Axboe]

On 8/14/21 1:31 PM, Pavel Begunkov wrote:
> On 8/14/21 8:13 PM, Jens Axboe wrote:
>> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>>> been refcounted yet and we can save one req_ref_get() by setting the
>>> refcount number to the right value directly.
>>
>> Not sure this really matters, but can't hurt either. But...
> 
> The refcount patches made this one atomic worse, and I just prefer
> to not regress, even if slightly

Not really against it, but doubt it's measurable if you end up hitting
the io-wq slower path anyway. But as I said, can't really hurt, so not
aginst it.

>>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>>  	atomic_inc(&req->refs);
>>>  }
>>>  
>>> -static inline void io_req_refcount(struct io_kiocb *req)
>>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>>  {
>>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>>  		req->flags |= REQ_F_REFCOUNT;
>>> -		atomic_set(&req->refs, 1);
>>> +		atomic_set(&req->refs, nr);
>>>  	}
>>>  }
>>>  
>>> +static inline void io_req_refcount(struct io_kiocb *req)
>>> +{
>>> +	__io_req_refcount(req, 1);
>>> +}
>>> +
>>
>> I really think these should be io_req_set_refcount() or something like
>> that, making it clear that we're actively setting/manipulating the ref
>> count.
> 
> Agree. A separate patch, maybe?

Maybe just fold it into this one, as it's splitting out a helper anyway.
Or do it as a prep patch before this one, up to you.

-- 
Jens Axboe

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Jens Axboe]

On 8/14/21 1:36 PM, Pavel Begunkov wrote:
> On 8/14/21 8:31 PM, Pavel Begunkov wrote:
>> On 8/14/21 8:13 PM, Jens Axboe wrote:
>>> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>>>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>>>> been refcounted yet and we can save one req_ref_get() by setting the
>>>> refcount number to the right value directly.
>>>
>>> Not sure this really matters, but can't hurt either. But...
>>
>> The refcount patches made this one atomic worse, and I just prefer
>> to not regress, even if slightly
>>
>>>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>>>  	atomic_inc(&req->refs);
>>>>  }
>>>>  
>>>> -static inline void io_req_refcount(struct io_kiocb *req)
>>>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>>>  {
>>>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>>>  		req->flags |= REQ_F_REFCOUNT;
>>>> -		atomic_set(&req->refs, 1);
>>>> +		atomic_set(&req->refs, nr);
>>>>  	}
>>>>  }
>>>>  
>>>> +static inline void io_req_refcount(struct io_kiocb *req)
>>>> +{
>>>> +	__io_req_refcount(req, 1);
>>>> +}
>>>> +
>>>
>>> I really think these should be io_req_set_refcount() or something like
>>> that, making it clear that we're actively setting/manipulating the ref
>>> count.
>>
>> Agree. A separate patch, maybe?
> 
> I mean it just would be a bit easier for me, instead of rebasing
> this series and not yet sent patches.

I think it should come before this series at least, or be folded into the
first patch. So probably no way around the rebase, sorry...
-- 
Jens Axboe

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Pavel Begunkov]

On 8/14/21 8:38 PM, Jens Axboe wrote:
> On 8/14/21 1:36 PM, Pavel Begunkov wrote:
>> On 8/14/21 8:31 PM, Pavel Begunkov wrote:
>>> On 8/14/21 8:13 PM, Jens Axboe wrote:
>>>> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>>>>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>>>>> been refcounted yet and we can save one req_ref_get() by setting the
>>>>> refcount number to the right value directly.
>>>>
>>>> Not sure this really matters, but can't hurt either. But...
>>>
>>> The refcount patches made this one atomic worse, and I just prefer
>>> to not regress, even if slightly
>>>
>>>>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>>>>  	atomic_inc(&req->refs);
>>>>>  }
>>>>>  
>>>>> -static inline void io_req_refcount(struct io_kiocb *req)
>>>>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>>>>  {
>>>>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>>>>  		req->flags |= REQ_F_REFCOUNT;
>>>>> -		atomic_set(&req->refs, 1);
>>>>> +		atomic_set(&req->refs, nr);
>>>>>  	}
>>>>>  }
>>>>>  
>>>>> +static inline void io_req_refcount(struct io_kiocb *req)
>>>>> +{
>>>>> +	__io_req_refcount(req, 1);
>>>>> +}
>>>>> +
>>>>
>>>> I really think these should be io_req_set_refcount() or something like
>>>> that, making it clear that we're actively setting/manipulating the ref
>>>> count.
>>>
>>> Agree. A separate patch, maybe?
>>
>> I mean it just would be a bit easier for me, instead of rebasing
>> this series and not yet sent patches.
> 
> I think it should come before this series at least, or be folded into the
> first patch. So probably no way around the rebase, sorry...

Don't see the point, but anyway, just resent it

-- 
Pavel Begunkov

Re: [PATCH 1/5] io_uring: optimise iowq refcounting

[Jens Axboe]

On 8/15/21 3:41 AM, Pavel Begunkov wrote:
> On 8/14/21 8:38 PM, Jens Axboe wrote:
>> On 8/14/21 1:36 PM, Pavel Begunkov wrote:
>>> On 8/14/21 8:31 PM, Pavel Begunkov wrote:
>>>> On 8/14/21 8:13 PM, Jens Axboe wrote:
>>>>> On 8/14/21 10:26 AM, Pavel Begunkov wrote:
>>>>>> If a requests is forwarded into io-wq, there is a good chance it hasn't
>>>>>> been refcounted yet and we can save one req_ref_get() by setting the
>>>>>> refcount number to the right value directly.
>>>>>
>>>>> Not sure this really matters, but can't hurt either. But...
>>>>
>>>> The refcount patches made this one atomic worse, and I just prefer
>>>> to not regress, even if slightly
>>>>
>>>>>> @@ -1115,14 +1115,19 @@ static inline void req_ref_get(struct io_kiocb *req)
>>>>>>  	atomic_inc(&req->refs);
>>>>>>  }
>>>>>>  
>>>>>> -static inline void io_req_refcount(struct io_kiocb *req)
>>>>>> +static inline void __io_req_refcount(struct io_kiocb *req, int nr)
>>>>>>  {
>>>>>>  	if (!(req->flags & REQ_F_REFCOUNT)) {
>>>>>>  		req->flags |= REQ_F_REFCOUNT;
>>>>>> -		atomic_set(&req->refs, 1);
>>>>>> +		atomic_set(&req->refs, nr);
>>>>>>  	}
>>>>>>  }
>>>>>>  
>>>>>> +static inline void io_req_refcount(struct io_kiocb *req)
>>>>>> +{
>>>>>> +	__io_req_refcount(req, 1);
>>>>>> +}
>>>>>> +
>>>>>
>>>>> I really think these should be io_req_set_refcount() or something like
>>>>> that, making it clear that we're actively setting/manipulating the ref
>>>>> count.
>>>>
>>>> Agree. A separate patch, maybe?
>>>
>>> I mean it just would be a bit easier for me, instead of rebasing
>>> this series and not yet sent patches.
>>
>> I think it should come before this series at least, or be folded into the
>> first patch. So probably no way around the rebase, sorry...
> 
> Don't see the point, but anyway, just resent it

That's the usual approach, first a prep patch to clean it up, then change
on top. The opposite might be easier since the other patches already exist,
but it's backwards in terms of ordering imho.

-- 
Jens Axboe