lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

sched/numa: Check current->mm before allocating NUMA faults

Browse Source 
task_numa_placement checks current->mm but after buffers for faults
have already been uselessly allocated. Move the check earlier.

[peterz@infradead.org: Identified the problem]

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-27-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Mel Gorman
2013-10-07 11:29:04 +01:00
committed by Ingo Molnar
parent ac8e895bd2
commit 9ff1d9ff3c
1 changed files with 4 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
kernel/sched/fair.c
View File

@@ -930,8 +930,6 @@ static void task_numa_placement(struct task_struct *p)
int seq, nid, max_nid = -1; int seq, nid, max_nid = -1;
unsigned long max_faults = 0; unsigned long max_faults = 0;
if (!p->mm) /* for example, ksmd faulting in a user's mm */
return;
seq = ACCESS_ONCE(p->mm->numa_scan_seq); seq = ACCESS_ONCE(p->mm->numa_scan_seq);
if (p->numa_scan_seq == seq) if (p->numa_scan_seq == seq)
return; return;
@@ -998,6 +996,10 @@ void task_numa_fault(int last_nid, int node, int pages, bool migrated)
if (!numabalancing_enabled) if (!numabalancing_enabled)
return; return;
/* for example, ksmd faulting in a user's mm */
if (!p->mm)
return;
/* For now, do not attempt to detect private/shared accesses */ /* For now, do not attempt to detect private/shared accesses */
priv = 1; priv = 1;