| Date | Wed, 9 Oct 2013 10:28:12 -0700 | From | tip-bot for Mel Gorman <> | Subject | [tip:sched/core] sched/numa: Check current-> mm before allocating NUMA faults |
| |
Commit-ID: 9ff1d9ff3c2c8ab3feaeb2e8056a07ca293f7bde Gitweb: http://git.kernel.org/tip/9ff1d9ff3c2c8ab3feaeb2e8056a07ca293f7bde Author: Mel Gorman <mgorman@suse.de> AuthorDate: Mon, 7 Oct 2013 11:29:04 +0100 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Wed, 9 Oct 2013 12:40:31 +0200
sched/numa: Check current->mm before allocating NUMA faults
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> --- kernel/sched/fair.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 89eeb89..3383079 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -930,8 +930,6 @@ static void task_numa_placement(struct task_struct *p) int seq, nid, max_nid = -1; 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); if (p->numa_scan_seq == seq) return; @@ -998,6 +996,10 @@ void task_numa_fault(int last_nid, int node, int pages, bool migrated) if (!numabalancing_enabled) return; + /* for example, ksmd faulting in a user's mm */ + if (!p->mm) + return; + /* For now, do not attempt to detect private/shared accesses */ priv = 1;
|