diff options
author | Tejun Heo <tj@kernel.org> | 2014-06-28 08:10:14 -0400 |
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committer | Tejun Heo <tj@kernel.org> | 2014-06-28 08:10:14 -0400 |
commit | 2d7227828e1475c7b272e55bd70c4cec8eea219a (patch) | |
tree | 068171c424acc2390b1e6ecf514182c82cc5811d /kernel | |
parent | 9a1049da9bd2cd83fe11d46433e603c193aa9c71 (diff) |
percpu-refcount: implement percpu_ref_reinit() and percpu_ref_is_zero()
Now that explicit invocation of percpu_ref_exit() is necessary to free
the percpu counter, we can implement percpu_ref_reinit() which
reinitializes a released percpu_ref. This can be used implement
scalable gating switch which can be drained and then re-opened without
worrying about memory allocation failures.
percpu_ref_is_zero() is added to be used in a sanity check in
percpu_ref_exit(). As this function will be useful for other purposes
too, make it a public interface.
v2: Use smp_read_barrier_depends() instead of smp_load_acquire(). We
only need data dep barrier and smp_load_acquire() is stronger and
heavier on some archs. Spotted by Lai Jiangshan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Diffstat (limited to 'kernel')
0 files changed, 0 insertions, 0 deletions