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| author | Li Zefan <lizf@cn.fujitsu.com> | 2008-07-25 01:47:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-25 10:53:38 -0700 |
| commit | c372e817afc629fea9ff6321313325ed0b4a855b (patch) | |
| tree | 931188486a41a7923e4eb9b658a272b256b3c048 /kernel/cpuset.c | |
| parent | f9b4fb8dabf38fb456c97f01aace07cb6e7c1723 (diff) | |
| download | linux-c372e817afc629fea9ff6321313325ed0b4a855b.tar.gz linux-c372e817afc629fea9ff6321313325ed0b4a855b.tar.bz2 linux-c372e817afc629fea9ff6321313325ed0b4a855b.zip | |
cpuset: avoid unnecessary sched domains rebuilding
When changing 'sched_relax_domain_level', don't rebuild sched domains if
'cpus' is empty or 'sched_load_balance' is not set.
Also make the comments of rebuild_sched_domains() more readable.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/cpuset.c')
| -rw-r--r-- | kernel/cpuset.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 6eae6639e851..60d2c4702c6c 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -496,11 +496,16 @@ update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c) /* * rebuild_sched_domains() * - * If the flag 'sched_load_balance' of any cpuset with non-empty - * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset - * which has that flag enabled, or if any cpuset with a non-empty - * 'cpus' is removed, then call this routine to rebuild the - * scheduler's dynamic sched domains. + * This routine will be called to rebuild the scheduler's dynamic + * sched domains: + * - if the flag 'sched_load_balance' of any cpuset with non-empty + * 'cpus' changes, + * - or if the 'cpus' allowed changes in any cpuset which has that + * flag enabled, + * - or if the 'sched_relax_domain_level' of any cpuset which has + * that flag enabled and with non-empty 'cpus' changes, + * - or if any cpuset with non-empty 'cpus' is removed, + * - or if a cpu gets offlined. * * This routine builds a partial partition of the systems CPUs * (the set of non-overlappping cpumask_t's in the array 'part' @@ -1076,7 +1081,8 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val) if (val != cs->relax_domain_level) { cs->relax_domain_level = val; - rebuild_sched_domains(); + if (!cpus_empty(cs->cpus_allowed) && is_sched_load_balance(cs)) + rebuild_sched_domains(); } return 0; |