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| author | Srikar Dronamraju <srikar@linux.vnet.ibm.com> | 2015-08-11 21:54:21 +0530 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-09-13 09:52:54 +0200 |
| commit | 2a595721a1fa6b684c1c818f379bef834ac3d65e (patch) | |
| tree | 36ad793dceb62bdefefb9ec58d0f98d017c61676 | |
| parent | 2b49d84b259fc18e131026e5d38e7855352f71b9 (diff) | |
| download | op-kernel-dev-2a595721a1fa6b684c1c818f379bef834ac3d65e.zip op-kernel-dev-2a595721a1fa6b684c1c818f379bef834ac3d65e.tar.gz | |
sched/numa: Convert sched_numa_balancing to a static_branch
Variable sched_numa_balancing toggles numa_balancing feature. Hence
moving from a simple read mostly variable to a more apt static_branch.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1439310261-16124-1-git-send-email-srikar@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | kernel/sched/core.c | 10 | ||||
| -rw-r--r-- | kernel/sched/fair.c | 6 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 6 |
3 files changed, 11 insertions, 11 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index e0bd88b..b621271 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2114,12 +2114,16 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) #endif /* CONFIG_NUMA_BALANCING */ } +DEFINE_STATIC_KEY_FALSE(sched_numa_balancing); + #ifdef CONFIG_NUMA_BALANCING -__read_mostly bool sched_numa_balancing; void set_numabalancing_state(bool enabled) { - sched_numa_balancing = enabled; + if (enabled) + static_branch_enable(&sched_numa_balancing); + else + static_branch_disable(&sched_numa_balancing); } #ifdef CONFIG_PROC_SYSCTL @@ -2128,7 +2132,7 @@ int sysctl_numa_balancing(struct ctl_table *table, int write, { struct ctl_table t; int err; - int state = sched_numa_balancing; + int state = static_branch_likely(&sched_numa_balancing); if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index e8f0828..47ece22 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2069,7 +2069,7 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags) int local = !!(flags & TNF_FAULT_LOCAL); int priv; - if (!sched_numa_balancing) + if (!static_branch_likely(&sched_numa_balancing)) return; /* for example, ksmd faulting in a user's mm */ @@ -5562,7 +5562,7 @@ static int migrate_degrades_locality(struct task_struct *p, struct lb_env *env) unsigned long src_faults, dst_faults; int src_nid, dst_nid; - if (!sched_numa_balancing) + if (!static_branch_likely(&sched_numa_balancing)) return -1; if (!p->numa_faults || !(env->sd->flags & SD_NUMA)) @@ -7874,7 +7874,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) entity_tick(cfs_rq, se, queued); } - if (sched_numa_balancing) + if (!static_branch_unlikely(&sched_numa_balancing)) task_tick_numa(rq, curr); } diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 0d8f885..2e8530d0 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1003,11 +1003,7 @@ extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ -#ifdef CONFIG_NUMA_BALANCING -extern bool sched_numa_balancing; -#else -#define sched_numa_balancing (0) -#endif /* CONFIG_NUMA_BALANCING */ +extern struct static_key_false sched_numa_balancing; static inline u64 global_rt_period(void) { |
