lkml.org 
[lkml]   [2005]   [Nov]   [4]   [last100]   RSS Feed
Views: [more markup]   [less markup]   [headers]   [forward]  
 
Messages in this thread
Patch in this message
/
DateFri, 4 Nov 2005 00:28:33 -0800 (PST)
FromPaul Jackson <>
Subject[PATCH 6/5] cpuset: rebind numa vma mempolicy fix
The patch:
  [PATCH 2/5] cpuset: rebind numa vma mempolicy
requires this fix to avoid a deadlock situation
in certain cpuset removal cases.

It's ok to not complete the refresh_mems() operation
if we notice we are already holding mmap_sem.  We
will try again, next time we allocate memory.

Signed-off-by: Paul Jackson <pj@sgi.com>

---
 (This fix was included in my testing, but in another
  patch that has not been sent in yet.)

 kernel/cpuset.c |    5 +++++
 1 files changed, 5 insertions(+)
--- 2.6.14-rc5-mm1-cpuset-patches.orig/kernel/cpuset.c	2005-11-03 21:18:26.783391082 -0800
+++ 2.6.14-rc5-mm1-cpuset-patches/kernel/cpuset.c	2005-11-03 23:11:15.480042373 -0800
@@ -656,7 +656,12 @@ static void refresh_mems(void)
 	if (current->cpuset_mems_generation != my_cpusets_mem_gen) {
 		struct cpuset *cs;
 		nodemask_t oldmem = current->mems_allowed;
+		struct mm_struct *mm = current->mm;
 
+		/* numa_policy_rebind() needs mmap_sem - don't nest */
+		if (!mm || !down_write_trylock(&mm->mmap_sem))
+			return;
+		up_write(&mm->mmap_sem);
 		down(&callback_sem);
 		task_lock(current);
 		cs = current->cpuset;
-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-11-04 08:31    [W:0.266 / U:0.040 seconds]
©2003-2008 Jasper Spaans