[src/trunk]: src/sys/kern wapbl_biodone: Release the buffer before reclaiming...

[hannken <hannken%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c855aec3304a
branches:  trunk
changeset: 782719:c855aec3304a
user:      hannken <hannken%NetBSD.org@localhost>
date:      Sat Nov 17 10:10:17 2012 +0000

description:
wapbl_biodone: Release the buffer before reclaiming the log.
    wapbl_flush() may wait for the log to become empty and
    all buffers should be unbusy before it returns.

diffstat:

 sys/kern/vfs_wapbl.c |  27 ++++++++++++++++++---------
 1 files changed, 18 insertions(+), 9 deletions(-)

diffs (74 lines):

diff -r 04180fb68fd0 -r c855aec3304a sys/kern/vfs_wapbl.c
--- a/sys/kern/vfs_wapbl.c      Sat Nov 17 04:57:25 2012 +0000
+++ b/sys/kern/vfs_wapbl.c      Sat Nov 17 10:10:17 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_wapbl.c,v 1.52 2012/04/29 22:55:11 chs Exp $       */
+/*     $NetBSD: vfs_wapbl.c,v 1.53 2012/11/17 10:10:17 hannken Exp $   */
 
 /*-
  * Copyright (c) 2003, 2008, 2009 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
 #define WAPBL_INTERNAL
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_wapbl.c,v 1.52 2012/04/29 22:55:11 chs Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_wapbl.c,v 1.53 2012/11/17 10:10:17 hannken Exp $");
 
 #include <sys/param.h>
 #include <sys/bitops.h>
@@ -1224,6 +1224,9 @@
 {
        struct wapbl_entry *we = bp->b_private;
        struct wapbl *wl = we->we_wapbl;
+#ifdef WAPBL_DEBUG_BUFBYTES
+       const int bufsize = bp->b_bufsize;
+#endif
 
        /*
         * Handle possible flushing of buffers after log has been
@@ -1233,8 +1236,8 @@
                KASSERT(we->we_bufcount > 0);
                we->we_bufcount--;
 #ifdef WAPBL_DEBUG_BUFBYTES
-               KASSERT(we->we_unsynced_bufbytes >= bp->b_bufsize);
-               we->we_unsynced_bufbytes -= bp->b_bufsize;
+               KASSERT(we->we_unsynced_bufbytes >= bufsize);
+               we->we_unsynced_bufbytes -= bufsize;
 #endif
 
                if (we->we_bufcount == 0) {
@@ -1300,15 +1303,22 @@
 #endif
        }
 
+       /*
+        * Release the buffer here. wapbl_flush() may wait for the
+        * log to become empty and we better unbusy the buffer before
+        * wapbl_flush() returns.
+        */
+       brelse(bp, 0);
+
        mutex_enter(&wl->wl_mtx);
 
        KASSERT(we->we_bufcount > 0);
        we->we_bufcount--;
 #ifdef WAPBL_DEBUG_BUFBYTES
-       KASSERT(we->we_unsynced_bufbytes >= bp->b_bufsize);
-       we->we_unsynced_bufbytes -= bp->b_bufsize;
-       KASSERT(wl->wl_unsynced_bufbytes >= bp->b_bufsize);
-       wl->wl_unsynced_bufbytes -= bp->b_bufsize;
+       KASSERT(we->we_unsynced_bufbytes >= bufsize);
+       we->we_unsynced_bufbytes -= bufsize;
+       KASSERT(wl->wl_unsynced_bufbytes >= bufsize);
+       wl->wl_unsynced_bufbytes -= bufsize;
 #endif
 
        /*
@@ -1345,7 +1355,6 @@
        }
 
        mutex_exit(&wl->wl_mtx);
-       brelse(bp, 0);
 }
 
 /*