[src/trunk]: src/sys/kern Delete debugging option wapbl_lazy_truncate. Simpl...

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

details:   https://anonhg.NetBSD.org/src/rev/d0390458fb9a
branches:  trunk
changeset: 345107:d0390458fb9a
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat May 07 20:39:33 2016 +0000

description:
Delete debugging option wapbl_lazy_truncate.  Simplify.

Likely nobody has used this in the past decade -- you would have to
enter ddb and write 1 to it in order to enable it anyway.

Patch prepared by coypu.

diffstat:

 sys/kern/vfs_wapbl.c |  40 ++++++++++++++--------------------------
 1 files changed, 14 insertions(+), 26 deletions(-)

diffs (103 lines):

diff -r 864ed70aac03 -r d0390458fb9a sys/kern/vfs_wapbl.c
--- a/sys/kern/vfs_wapbl.c      Sat May 07 20:18:44 2016 +0000
+++ b/sys/kern/vfs_wapbl.c      Sat May 07 20:39:33 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_wapbl.c,v 1.72 2016/05/07 20:18:44 riastradh Exp $ */
+/*     $NetBSD: vfs_wapbl.c,v 1.73 2016/05/07 20:39:33 riastradh 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 1.72 2016/05/07 20:18:44 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_wapbl.c,v 1.73 2016/05/07 20:39:33 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/bitops.h>
@@ -269,12 +269,6 @@
 
 static int wapbl_replay_isopen1(struct wapbl_replay *);
 
-/*
- * This is useful for debugging.  If set, the log will
- * only be truncated when necessary.
- */
-int wapbl_lazy_truncate = 0;
-
 struct wapbl_ops wapbl_ops = {
        .wo_wapbl_discard       = wapbl_discard,
        .wo_wapbl_replay_isopen = wapbl_replay_isopen1,
@@ -1295,19 +1289,18 @@
 /****************************************************************/
 
 /*
- * wapbl_truncate(wl, minfree, waitonly)
+ * wapbl_truncate(wl, minfree)
  *
  *     Wait until at least minfree bytes are available in the log.
  *
- *     If it was necessary to wait for writes to complete, and if
- *     waitonly is not true, advance the circular queue tail to
- *     reflect the new write completions and issue a write commit to
- *     the log.
+ *     If it was necessary to wait for writes to complete,
+ *     advance the circular queue tail to reflect the new write
+ *     completions and issue a write commit to the log.
  *
  *     => Caller must hold wl->wl_rwlock writer lock.
  */
 static int
-wapbl_truncate(struct wapbl *wl, size_t minfree, int waitonly)
+wapbl_truncate(struct wapbl *wl, size_t minfree)
 {
        size_t delta;
        size_t avail;
@@ -1366,9 +1359,6 @@
        if (error)
                return error;
 
-       if (waitonly)
-               return 0;
-
        /*
         * This is where head, tail and delta are unprotected
         * from races against itself or flush.  This is ok since
@@ -1624,7 +1614,7 @@
                panic("wapbl_flush: current transaction too big to flush");
        }
 
-       error = wapbl_truncate(wl, flushsize, 0);
+       error = wapbl_truncate(wl, flushsize);
        if (error)
                goto out;
 
@@ -1658,13 +1648,11 @@
            flushsize);
 
        /* Opportunistically move the tail forward if we can */
-       if (!wapbl_lazy_truncate) {
-               mutex_enter(&wl->wl_mtx);
-               delta = wl->wl_reclaimable_bytes;
-               mutex_exit(&wl->wl_mtx);
-               wapbl_advance_tail(wl->wl_circ_size, wl->wl_circ_off, delta,
-                   &head, &tail);
-       }
+       mutex_enter(&wl->wl_mtx);
+       delta = wl->wl_reclaimable_bytes;
+       mutex_exit(&wl->wl_mtx);
+       wapbl_advance_tail(wl->wl_circ_size, wl->wl_circ_off, delta,
+           &head, &tail);
 
        error = wapbl_write_commit(wl, head, tail);
        if (error)
@@ -1754,7 +1742,7 @@
         */
        if (waitfor) {
                error = wapbl_truncate(wl, wl->wl_circ_size - 
-                       wl->wl_reserved_bytes, wapbl_lazy_truncate);
+                       wl->wl_reserved_bytes);
        }
 
  out: