Messages in this thread Patch in this message | | | From | Jesper Dangaard Brouer <> | Subject | [PATCH 09/10] cfq-iosched: Uses its own open-coded rcu_barrier. | Date | Tue, 23 Jun 2009 17:04:39 +0200 |
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This module cfq-iosched, has discovered the value of waiting for call_rcu() completion, but its has its own open-coded implementation of rcu_barrier(), which I don't think is 'strong' enough.
This patch only leaves a comment for the maintainers to consider.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk> ---
block/cfq-iosched.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 833ec18..c15555b 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2657,6 +2657,12 @@ static void __exit cfq_exit(void) /* * this also protects us from entering cfq_slab_kill() with * pending RCU callbacks + * + * hawk@comx.dk 2009-06-18: Maintainer please consider using + * rcu_barrier() instead of this open-coded wait for + * completion implementation. I think it provides a better + * guarantee that all CPUs are finished, although + * elv_ioc_count_read() do consider all CPUs. */ if (elv_ioc_count_read(ioc_count)) wait_for_completion(&all_gone);
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