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| author | Peter Zijlstra <peterz@infradead.org> | 2013-10-07 11:29:33 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-10-09 14:48:10 +0200 |
| commit | 0ec8aa00f2b4dc457836ef4e2662b02483e94fb7 (patch) | |
| tree | ffd621a5f639a10b1a7213892649e512ea0ee1ba /kernel/sched/sched.h | |
| parent | ca28aa53dd95868c9e38917b9881c09dacfacf1a (diff) | |
| download | lwn-0ec8aa00f2b4dc457836ef4e2662b02483e94fb7.tar.gz lwn-0ec8aa00f2b4dc457836ef4e2662b02483e94fb7.zip | |
sched/numa: Avoid migrating tasks that are placed on their preferred node
This patch classifies scheduler domains and runqueues into types depending
the number of tasks that are about their NUMA placement and the number
that are currently running on their preferred node. The types are
regular: There are tasks running that do not care about their NUMA
placement.
remote: There are tasks running that care about their placement but are
currently running on a node remote to their ideal placement
all: No distinction
To implement this the patch tracks the number of tasks that are optimally
NUMA placed (rq->nr_preferred_running) and the number of tasks running
that care about their placement (nr_numa_running). The load balancer
uses this information to avoid migrating idea placed NUMA tasks as long
as better options for load balancing exists. For example, it will not
consider balancing between a group whose tasks are all perfectly placed
and a group with remote tasks.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
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>
Link: http://lkml.kernel.org/r/1381141781-10992-56-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/sched.h')
| -rw-r--r-- | kernel/sched/sched.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index eeb1923812a1..d69cb325c27e 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -409,6 +409,10 @@ struct rq { * remote CPUs use both these fields when doing load calculation. */ unsigned int nr_running; +#ifdef CONFIG_NUMA_BALANCING + unsigned int nr_numa_running; + unsigned int nr_preferred_running; +#endif #define CPU_LOAD_IDX_MAX 5 unsigned long cpu_load[CPU_LOAD_IDX_MAX]; unsigned long last_load_update_tick; @@ -557,6 +561,7 @@ static inline u64 rq_clock_task(struct rq *rq) } #ifdef CONFIG_NUMA_BALANCING +extern void sched_setnuma(struct task_struct *p, int node); extern int migrate_task_to(struct task_struct *p, int cpu); extern int migrate_swap(struct task_struct *, struct task_struct *); #endif /* CONFIG_NUMA_BALANCING */ |