Module Name: src
Committed By: ad
Date: Sun Dec 8 19:26:05 UTC 2019
Modified Files:
src/sys/kern: vfs_bio.c
Log Message:
- Avoid thundering herd: cv_broadcast(&bp->b_busy) -> cv_signal(&bp->b_busy)
- Sprinkle __cacheline_aligned.
To generate a diff of this commit:
cvs rdiff -u -r1.279 -r1.280 src/sys/kern/vfs_bio.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/vfs_bio.c
diff -u src/sys/kern/vfs_bio.c:1.279 src/sys/kern/vfs_bio.c:1.280
--- src/sys/kern/vfs_bio.c:1.279 Mon Aug 26 10:24:39 2019
+++ src/sys/kern/vfs_bio.c Sun Dec 8 19:26:05 2019
@@ -1,7 +1,7 @@
-/* $NetBSD: vfs_bio.c,v 1.279 2019/08/26 10:24:39 msaitoh Exp $ */
+/* $NetBSD: vfs_bio.c,v 1.280 2019/12/08 19:26:05 ad Exp $ */
/*-
- * Copyright (c) 2007, 2008, 2009 The NetBSD Foundation, Inc.
+ * Copyright (c) 2007, 2008, 2009, 2019 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
@@ -123,7 +123,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_bio.c,v 1.279 2019/08/26 10:24:39 msaitoh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_bio.c,v 1.280 2019/12/08 19:26:05 ad Exp $");
#ifdef _KERNEL_OPT
#include "opt_bufcache.h"
@@ -184,7 +184,7 @@ struct bqueue {
uint64_t bq_bytes;
buf_t *bq_marker;
};
-static struct bqueue bufqueues[BQUEUES];
+static struct bqueue bufqueues[BQUEUES] __cacheline_aligned;
/* Function prototypes */
static void buf_setwm(void);
@@ -237,8 +237,8 @@ static kcondvar_t needbuffer_cv;
/*
* Buffer queue lock.
*/
-kmutex_t bufcache_lock;
-kmutex_t buffer_lock;
+kmutex_t bufcache_lock __cacheline_aligned;
+kmutex_t buffer_lock __cacheline_aligned;
/* Software ISR for completed transfers. */
static void *biodone_sih;
@@ -1140,7 +1140,7 @@ already_queued:
/* Unlock the buffer. */
CLR(bp->b_cflags, BC_AGE|BC_BUSY|BC_NOCACHE);
CLR(bp->b_flags, B_ASYNC);
- cv_broadcast(&bp->b_busy);
+ cv_signal(&bp->b_busy);
if (bp->b_bufsize <= 0)
brele(bp);
