NetBSD Problem Report #51422

From jose@pc2.bigmail.com  Thu Aug 18 02:31:32 2016
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Date: Thu, 18 Aug 2016 04:31:17 +0200 (CEST)
From: joseyluis@gmail.com
Reply-To: joseyluis@gmail.com
To: gnats-bugs@NetBSD.org
Subject: unnecesary assignation in buf_destroy sbin/fsck_lfs/bufcache.c
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>Number:         51422
>Category:       bin
>Synopsis:       unnecesary assignation in buf_destroy sbin/fsck_lfs/bufcache.c
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    bin-bug-people
>State:          closed
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Aug 18 02:35:00 +0000 2016
>Closed-Date:    Sun Nov 13 23:26:13 +0000 2016
>Last-Modified:  Sun Nov 13 23:26:13 +0000 2016
>Originator:     Jose Luis Rodriguez Garcia
>Release:        current
>Organization:

>Environment:
>Description:
	In bufcache.c the assignation bp->b_flags |= B_NEEDCOMMIT; is
unncesary because in the same function bp is freed with: free(bp);is
>How-To-Repeat:
code review
>Fix:
Index: bufcache.c
===================================================================
RCS file: /cvsroot/src/sbin/fsck_lfs/bufcache.c,v
retrieving revision 1.16
diff -u -r1.16 bufcache.c
--- bufcache.c  31 Jul 2016 18:27:26 -0000      1.16
+++ bufcache.c  18 Aug 2016 02:17:21 -0000
@@ -155,7 +155,6 @@
 void
 buf_destroy(struct ubuf * bp)
 {
-       bp->b_flags |= B_NEEDCOMMIT;
	LIST_REMOVE(bp, b_vnbufs);
	LIST_REMOVE(bp, b_hash);
	if (!(bp->b_flags & B_DONTFREE))

>Release-Note:

>Audit-Trail:
From: Jose Luis Rodriguez Garcia <joseyluis@gmail.com>
To: gnats-bugs@netbsd.org
Cc: 
Subject: Re: bin/51422: unnecesary assignation in buf_destroy sbin/fsck_lfs/bufcache.c
Date: Thu, 18 Aug 2016 05:20:58 +0200

 Lookin further, it seems that B_NEEDCOMMIT is only used in
 sys/fs/nfs/client and sys/fs/smbfs.

 What was the purpose of the author of the code using B_NEEDCOMMIT?

 I send a new patch removing B_NEEDCOMMIT from the user bufer cache of lfs:



 Index: bufcache.c
 ===================================================================
 RCS file: /cvsroot/src/sbin/fsck_lfs/bufcache.c,v
 retrieving revision 1.16
 diff -u -r1.16 bufcache.c
 --- bufcache.c  31 Jul 2016 18:27:26 -0000      1.16
 +++ bufcache.c  18 Aug 2016 03:18:03 -0000
 @@ -155,7 +155,6 @@
  void
  buf_destroy(struct ubuf * bp)
  {
 -       bp->b_flags |= B_NEEDCOMMIT;
         LIST_REMOVE(bp, b_vnbufs);
         LIST_REMOVE(bp, b_hash);
         if (!(bp->b_flags & B_DONTFREE))
 @@ -231,7 +230,6 @@
          * the buffer, its contents are invalid; but shrinking is okay.
          */
         if ((bp = incore(vp, lbn)) != NULL) {
 -               assert(!(bp->b_flags & B_NEEDCOMMIT));
                 assert(!(bp->b_flags & B_BUSY));
                 bp->b_flags |= B_BUSY;
                 bremfree(bp);
 @@ -309,7 +307,6 @@
  {
         int age;

 -       assert(!(bp->b_flags & B_NEEDCOMMIT));
         assert(bp->b_flags & B_BUSY);

         bp->b_flags |= set;
 Index: bufcache.h
 ===================================================================
 RCS file: /cvsroot/src/sbin/fsck_lfs/bufcache.h,v
 retrieving revision 1.12
 diff -u -r1.12 bufcache.h
 --- bufcache.h  29 Mar 2015 19:35:58 -0000      1.12
 +++ bufcache.h  18 Aug 2016 03:18:03 -0000
 @@ -92,7 +92,6 @@
   * These flags are kept in b_flags.
   */
  #define        B_AGE           0x00000001      /* Move to age queue
 when I/O done. */
 -#define        B_NEEDCOMMIT    0x00000002      /* Needs committing to
 stable storage */
  #define        B_BUSY          0x00000010      /* I/O in progress. */
  #define        B_DELWRI        0x00000080      /* Delay I/O until
 buffer reused. */
  #define        B_DONE          0x00000200      /* I/O completed. */



 On Thu, Aug 18, 2016 at 4:35 AM,  <gnats-admin@netbsd.org> wrote:
 > Thank you very much for your problem report.
 > It has the internal identification `bin/51422'.
 > The individual assigned to look at your
 > report is: bin-bug-people.
 >
 >>Category:       bin
 >>Responsible:    bin-bug-people
 >>Synopsis:       unnecesary assignation in buf_destroy sbin/fsck_lfs/bufcache.c
 >>Arrival-Date:   Thu Aug 18 02:35:00 +0000 2016
 >

From: "Christos Zoulas" <christos@netbsd.org>
To: gnats-bugs@gnats.NetBSD.org
Cc: 
Subject: PR/51422 CVS commit: src/sbin/fsck_lfs
Date: Thu, 18 Aug 2016 04:04:28 -0400

 Module Name:	src
 Committed By:	christos
 Date:		Thu Aug 18 08:04:28 UTC 2016

 Modified Files:
 	src/sbin/fsck_lfs: bufcache.c

 Log Message:
 PR/51422: Jose Luis Rodriguez Garcia: Remove unnecessary assignment.


 To generate a diff of this commit:
 cvs rdiff -u -r1.16 -r1.17 src/sbin/fsck_lfs/bufcache.c

 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.

From: "Christos Zoulas" <christos@netbsd.org>
To: gnats-bugs@gnats.NetBSD.org
Cc: 
Subject: PR/51422 CVS commit: src/sbin/fsck_lfs
Date: Thu, 18 Aug 2016 04:08:02 -0400

 Module Name:	src
 Committed By:	christos
 Date:		Thu Aug 18 08:08:02 UTC 2016

 Modified Files:
 	src/sbin/fsck_lfs: bufcache.c bufcache.h

 Log Message:
 PR/51422: Jose Luis Rodriguez Garcia: completely remove B_NEEDCOMMIT


 To generate a diff of this commit:
 cvs rdiff -u -r1.17 -r1.18 src/sbin/fsck_lfs/bufcache.c
 cvs rdiff -u -r1.12 -r1.13 src/sbin/fsck_lfs/bufcache.h

 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.

State-Changed-From-To: open->closed
State-Changed-By: dholland@NetBSD.org
State-Changed-When: Sun, 13 Nov 2016 23:26:13 +0000
State-Changed-Why:
christos committed it in august


>Unformatted:

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