diff options
| author | Mel Gorman <mgorman@suse.de> | 2012-11-22 14:40:03 +0000 |
|---|---|---|
| committer | Mel Gorman <mgorman@suse.de> | 2012-12-11 14:42:56 +0000 |
| commit | 5bca23035391928c4c7301835accca3551b96cc2 (patch) | |
| tree | 2feb63abf318e6edfded8bb97b43ca29c3c5b312 /include/linux | |
| parent | 3105b86a9fee7d2c2e76edb53bbbc4027599628f (diff) | |
mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node
Due to the fact that migrations are driven by the CPU a task is running
on there is no point tracking NUMA faults until one task runs on a new
node. This patch tracks the first node used by an address space. Until
it changes, PTE scanning is disabled and no NUMA hinting faults are
trapped. This should help workloads that are short-lived, do not care
about NUMA placement or have bound themselves to a single node.
This takes advantage of the logic in "mm: sched: numa: Implement slow
start for working set sampling" to delay when the checks are made. This
will take advantage of processes that set their CPU and node bindings
early in their lifetime. It will also potentially allow any initial load
balancing to take place.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/mm_types.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index e850a23dd6ec..197422a1598c 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -418,10 +418,20 @@ struct mm_struct { /* numa_scan_seq prevents two threads setting pte_numa */ int numa_scan_seq; + + /* + * The first node a task was scheduled on. If a task runs on + * a different node than Make PTE Scan Go Now. + */ + int first_nid; #endif struct uprobes_state uprobes_state; }; +/* first nid will either be a valid NID or one of these values */ +#define NUMA_PTE_SCAN_INIT -1 +#define NUMA_PTE_SCAN_ACTIVE -2 + static inline void mm_init_cpumask(struct mm_struct *mm) { #ifdef CONFIG_CPUMASK_OFFSTACK |