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* [PATCH] Silence warning if CONFIG_LOCKDEP isn't set
@ 2013-01-24 20:53 Paul Bolle
  2013-01-25 10:40 ` [tip:core/locking] lockdep: Silence warning if CONFIG_LOCKDEP isn 't set tip-bot for Paul Bolle
  2013-02-22 12:24 ` tip-bot for Paul Bolle
  0 siblings, 2 replies; 3+ messages in thread
From: Paul Bolle @ 2013-01-24 20:53 UTC (permalink / raw)
  To: Peter Zijlstra, Ingo Molnar, Stanislav Kinsbursky, J. Bruce Fields
  Cc: linux-kernel

Since commit c9a4962881929df7f1ef6e63e1b9da304faca4dd ("nfsd: make
client_lock per net") compiling nfs4state.o without CONFIG_LOCKDEP set,
triggers this GCC warning:
    fs/nfsd/nfs4state.c: In function ‘free_client’:
    fs/nfsd/nfs4state.c:1051:19: warning: unused variable ‘nn’ [-Wunused-variable]

The cause of that warning is that lockdep_assert_held() compiles away if
CONFIG_LOCKDEP is not set. Silence this warning by using the argument to
lockdep_assert_held() as a nop if CONFIG_LOCKDEP is not set.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
---
0) Compile tested only.

1) This patch triggers a checkpatch false positive:
    WARNING: Single statement macros should not use a do {} while (0) loop

2) Review is rather needed here, since I'm not sure what, if any, the
downsides are of this patch for all other "calls" of
lockdep_assert_held(). Besides, a cleaner solution might be to simply
drop lockdep_assert_held() in free_client(). There are only three
callers of that function and it seems obvious that all three do hold
'client_lock'.

 include/linux/lockdep.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 2bca44b..f05631e 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -410,7 +410,7 @@ struct lock_class_key { };
 
 #define lockdep_depth(tsk)	(0)
 
-#define lockdep_assert_held(l)			do { } while (0)
+#define lockdep_assert_held(l)			do { (void)(l); } while (0)
 
 #define lockdep_recursing(tsk)			(0)
 
-- 
1.7.11.7


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [tip:core/locking] lockdep: Silence warning if CONFIG_LOCKDEP isn 't set
  2013-01-24 20:53 [PATCH] Silence warning if CONFIG_LOCKDEP isn't set Paul Bolle
@ 2013-01-25 10:40 ` tip-bot for Paul Bolle
  2013-02-22 12:24 ` tip-bot for Paul Bolle
  1 sibling, 0 replies; 3+ messages in thread
From: tip-bot for Paul Bolle @ 2013-01-25 10:40 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, peterz, bfields, pebolle, skinsbursky, tglx

Commit-ID:  61b48fd031db92de6fe74ebba4bc3799bd55c3fa
Gitweb:     http://git.kernel.org/tip/61b48fd031db92de6fe74ebba4bc3799bd55c3fa
Author:     Paul Bolle <pebolle@tiscali.nl>
AuthorDate: Thu, 24 Jan 2013 21:53:17 +0100
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 25 Jan 2013 08:43:57 +0100

lockdep: Silence warning if CONFIG_LOCKDEP isn't set

Since commit c9a4962881929df7f1ef6e63e1b9da304faca4dd ("nfsd:
make client_lock per net") compiling nfs4state.o without
CONFIG_LOCKDEP set, triggers this GCC warning:

    fs/nfsd/nfs4state.c: In function ‘free_client’:
    fs/nfsd/nfs4state.c:1051:19: warning: unused variable ‘nn’ [-Wunused-variable]

The cause of that warning is that lockdep_assert_held() compiles
away if CONFIG_LOCKDEP is not set. Silence this warning by using
the argument to lockdep_assert_held() as a nop if CONFIG_LOCKDEP
is not set.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Link: http://lkml.kernel.org/r/1359060797.1325.33.camel@x61.thuisdomein
Signed-off-by: Ingo Molnar <mingo@kernel.org>
--
 include/linux/lockdep.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
 include/linux/lockdep.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 2bca44b..f05631e 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -410,7 +410,7 @@ struct lock_class_key { };
 
 #define lockdep_depth(tsk)	(0)
 
-#define lockdep_assert_held(l)			do { } while (0)
+#define lockdep_assert_held(l)			do { (void)(l); } while (0)
 
 #define lockdep_recursing(tsk)			(0)
 

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [tip:core/locking] lockdep: Silence warning if CONFIG_LOCKDEP isn 't set
  2013-01-24 20:53 [PATCH] Silence warning if CONFIG_LOCKDEP isn't set Paul Bolle
  2013-01-25 10:40 ` [tip:core/locking] lockdep: Silence warning if CONFIG_LOCKDEP isn 't set tip-bot for Paul Bolle
@ 2013-02-22 12:24 ` tip-bot for Paul Bolle
  1 sibling, 0 replies; 3+ messages in thread
From: tip-bot for Paul Bolle @ 2013-02-22 12:24 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, peterz, bfields, pebolle, skinsbursky, tglx

Commit-ID:  5cd3f5affad2109fd1458aab3f6216f2181e26ea
Gitweb:     http://git.kernel.org/tip/5cd3f5affad2109fd1458aab3f6216f2181e26ea
Author:     Paul Bolle <pebolle@tiscali.nl>
AuthorDate: Thu, 24 Jan 2013 21:53:17 +0100
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 19 Feb 2013 08:42:41 +0100

lockdep: Silence warning if CONFIG_LOCKDEP isn't set

Since commit c9a4962881929df7f1ef6e63e1b9da304faca4dd ("nfsd:
make client_lock per net") compiling nfs4state.o without
CONFIG_LOCKDEP set, triggers this GCC warning:

    fs/nfsd/nfs4state.c: In function ‘free_client’:
    fs/nfsd/nfs4state.c:1051:19: warning: unused variable ‘nn’ [-Wunused-variable]

The cause of that warning is that lockdep_assert_held() compiles
away if CONFIG_LOCKDEP is not set. Silence this warning by using
the argument to lockdep_assert_held() as a nop if CONFIG_LOCKDEP
is not set.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Link: http://lkml.kernel.org/r/1359060797.1325.33.camel@x61.thuisdomein
Signed-off-by: Ingo Molnar <mingo@kernel.org>
--
 include/linux/lockdep.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
 include/linux/lockdep.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 2bca44b..f05631e 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -410,7 +410,7 @@ struct lock_class_key { };
 
 #define lockdep_depth(tsk)	(0)
 
-#define lockdep_assert_held(l)			do { } while (0)
+#define lockdep_assert_held(l)			do { (void)(l); } while (0)
 
 #define lockdep_recursing(tsk)			(0)
 

^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2013-02-22 12:26 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-01-24 20:53 [PATCH] Silence warning if CONFIG_LOCKDEP isn't set Paul Bolle
2013-01-25 10:40 ` [tip:core/locking] lockdep: Silence warning if CONFIG_LOCKDEP isn 't set tip-bot for Paul Bolle
2013-02-22 12:24 ` tip-bot for Paul Bolle

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