lkml.org 
[lkml]   [2009]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:core/locking] lockdep: fix deadlock in lockdep_trace_alloc, take 2
Commit-ID:  da40a037c5ed51693e739ff9b21e013414244644
Gitweb: http://git.kernel.org/tip/da40a037c5ed51693e739ff9b21e013414244644
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Sat, 21 Mar 2009 13:33:08 +0100
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Sat, 21 Mar 2009 17:15:42 +0100

lockdep: fix deadlock in lockdep_trace_alloc, take 2

Since we now disabled IRQs, checking for IRQs disabled is a bit
pointless, check for it in the saved flags.

Also, add the missing check_flags() check for completeness.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: npiggin@suse.de
Cc: heiko.carstens@de.ibm.com
LKML-Reference: <1237638788.4667.263.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


---
kernel/lockdep.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index c750038..a288ae1 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -2257,7 +2257,7 @@ void trace_softirqs_off(unsigned long ip)
debug_atomic_inc(&redundant_softirqs_off);
}

-static void __lockdep_trace_alloc(gfp_t gfp_mask)
+static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags)
{
struct task_struct *curr = current;

@@ -2276,12 +2276,14 @@ static void __lockdep_trace_alloc(gfp_t gfp_mask)
if (!(gfp_mask & __GFP_FS))
return;

- if (DEBUG_LOCKS_WARN_ON(irqs_disabled()))
+ if (DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags)))
return;

mark_held_locks(curr, RECLAIM_FS);
}

+static void check_flags(unsigned long flags);
+
void lockdep_trace_alloc(gfp_t gfp_mask)
{
unsigned long flags;
@@ -2290,8 +2292,9 @@ void lockdep_trace_alloc(gfp_t gfp_mask)
return;

raw_local_irq_save(flags);
+ check_flags(flags);
current->lockdep_recursion = 1;
- __lockdep_trace_alloc(gfp_mask);
+ __lockdep_trace_alloc(gfp_mask, flags);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}

\
 
 \ /
  Last update: 2009-03-21 17:23    [W:0.051 / U:5.952 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site