Commit 552d0e17 authored by Jeff Layton's avatar Jeff Layton Committed by Chuck Lever
Browse files

sunrpc: convert queue_wait from global to per-cache-detail waitqueue 



The queue_wait waitqueue is currently a file-scoped global, so a
wake_up for one cache_detail wakes pollers on all caches. Convert it
to a per-cache-detail field so that only pollers on the relevant cache
are woken.

Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 17c1d665

include/linux/sunrpc/cache.h

+2 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/atomic.h>

#include <linux/kstrtox.h>

#include <linux/proc_fs.h>

#include <linux/wait.h>



/*

 * Each cache requires:
@@ -114,6 +115,7 @@ struct cache_detail { 
	/* fields for communication over channel */

	struct list_head	queue;

	spinlock_t		queue_lock;

	wait_queue_head_t	queue_wait;



	atomic_t		writers;		/* how many time is /channel open */

	time64_t		last_close;		/* if no writers, when did last close */

net/sunrpc/cache.c

+3 −4
Original line number Diff line number Diff line
@@ -401,6 +401,7 @@ void sunrpc_init_cache_detail(struct cache_detail *cd) 
	spin_lock_init(&cd->hash_lock);

	INIT_LIST_HEAD(&cd->queue);

	spin_lock_init(&cd->queue_lock);

	init_waitqueue_head(&cd->queue_wait);

	spin_lock(&cache_list_lock);

	cd->nextcheck = 0;

	cd->entries = 0;
@@ -970,8 +971,6 @@ static ssize_t cache_write(struct file *filp, const char __user *buf, 
	return ret;

}



static DECLARE_WAIT_QUEUE_HEAD(queue_wait);



static __poll_t cache_poll(struct file *filp, poll_table *wait,

			       struct cache_detail *cd)

{
@@ -979,7 +978,7 @@ static __poll_t cache_poll(struct file *filp, poll_table *wait, 
	struct cache_reader *rp = filp->private_data;

	struct cache_queue *cq;



	poll_wait(filp, &queue_wait, wait);

	poll_wait(filp, &cd->queue_wait, wait);



	/* alway allow write */

	mask = EPOLLOUT | EPOLLWRNORM;
@@ -1259,7 +1258,7 @@ static int cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h) 
		/* Lost a race, no longer PENDING, so don't enqueue */

		ret = -EAGAIN;

	spin_unlock(&detail->queue_lock);

	wake_up(&queue_wait);

	wake_up(&detail->queue_wait);

	if (ret == -EAGAIN) {

		kfree(buf);

		kfree(crq);