Messages in this thread Patch in this message | | | From | Frederic Weisbecker <> | Subject | [RFC PATCH 3/4] cgroups: New resource counter inheritance API | Date | Mon, 20 Jun 2011 01:51:13 +0200 |
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Provide an API to inherit a counter value from a parent. This can be useful to implement cgroup.clone_children on a resource counter.
Still the resources of the children are limited by those of the parent, so this is only to provide a default setting behaviour when clone_children is set.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrew Morton <akpm@linux-foundation.org> --- include/linux/res_counter.h | 2 ++ kernel/res_counter.c | 25 +++++++++++++++++++++++++ 2 files changed, 27 insertions(+), 0 deletions(-)
diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h index 1b3fe05..109d118 100644 --- a/include/linux/res_counter.h +++ b/include/linux/res_counter.h @@ -84,6 +84,8 @@ int res_counter_write(struct res_counter *counter, int member, void res_counter_write_u64(struct res_counter *counter, int member, u64 val); +void res_counter_inherit(struct res_counter *counter, int member); + /* * the field descriptors. one for each member of res_counter */ diff --git a/kernel/res_counter.c b/kernel/res_counter.c index 806d041..8cb0362 100644 --- a/kernel/res_counter.c +++ b/kernel/res_counter.c @@ -198,3 +198,28 @@ int res_counter_write(struct res_counter *counter, int member, return 0; } + +void res_counter_inherit(struct res_counter *counter, int member) +{ + struct res_counter *parent; + unsigned long long *pval, val; + unsigned long flags; + + parent = counter->parent; + if (!parent) + return; + + local_irq_save(flags); + + spin_lock(&counter->lock); + pval = res_counter_member(counter, member); + val = *pval; + spin_unlock(&counter->lock); + + spin_lock(&parent->lock); + pval = res_counter_member(parent, member); + *pval = val; + spin_unlock(&parent->lock); + + local_irq_restore(flags); +} -- 1.7.5.4
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