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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2011-04-07 14:09:58 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-04-11 14:05:00 +0200 |
| commit | 4cb988395da6e16627a8be69729e50cd72ebb23e (patch) | |
| tree | 17a655fbac5348de9a70ad8726354fa878bc66cb /kernel/sched.c | |
| parent | f96225fd51893b6650cffd5427f13f6b1b356488 (diff) | |
| download | lwn-4cb988395da6e16627a8be69729e50cd72ebb23e.tar.gz lwn-4cb988395da6e16627a8be69729e50cd72ebb23e.zip | |
sched: Avoid allocations in sched_domain_debug()
Since we're all serialized by sched_domains_mutex we can use
sched_domains_tmpmask and avoid having to do allocations. This means
we can use sched_domains_debug() for cpu_attach_domain() again.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20110407122942.664347467@chello.nl
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 17 |
1 files changed, 5 insertions, 12 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index fd73e91be089..35fc9959b564 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6395,6 +6395,8 @@ early_initcall(migration_init); #ifdef CONFIG_SMP +static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ + #ifdef CONFIG_SCHED_DEBUG static __read_mostly int sched_domain_debug_enabled; @@ -6490,7 +6492,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, static void sched_domain_debug(struct sched_domain *sd, int cpu) { - cpumask_var_t groupmask; int level = 0; if (!sched_domain_debug_enabled) @@ -6503,20 +6504,14 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu) printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); - if (!alloc_cpumask_var(&groupmask, GFP_KERNEL)) { - printk(KERN_DEBUG "Cannot load-balance (out of memory)\n"); - return; - } - for (;;) { - if (sched_domain_debug_one(sd, cpu, level, groupmask)) + if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) break; level++; sd = sd->parent; if (!sd) break; } - free_cpumask_var(groupmask); } #else /* !CONFIG_SCHED_DEBUG */ # define sched_domain_debug(sd, cpu) do { } while (0) @@ -6721,7 +6716,7 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) sd->child = NULL; } - /* sched_domain_debug(sd, cpu); */ + sched_domain_debug(sd, cpu); rq_attach_root(rq, rd); tmp = rq->sd; @@ -6851,8 +6846,6 @@ static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg) return cpu; } -static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ - /* * build_sched_groups takes the cpumask we wish to span, and a pointer * to a function which identifies what group(along with sched group) a CPU @@ -7896,8 +7889,8 @@ void __init sched_init(void) /* Allocate the nohz_cpu_mask if CONFIG_CPUMASK_OFFSTACK */ zalloc_cpumask_var(&nohz_cpu_mask, GFP_NOWAIT); - zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); #ifdef CONFIG_SMP + zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); #ifdef CONFIG_NO_HZ zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT); alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT); |