Messages in this thread | | | Date | Mon, 29 Aug 2011 23:26:49 +0800 | Subject | Re: blkdev_issue_discard() hangs forever if the underlying storage device is removed | From | Lin Ming <> |
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On Mon, Aug 29, 2011 at 11:16 PM, Lukas Czerner <lczerner@redhat.com> wrote: > On Mon, 29 Aug 2011, Lin Ming wrote: > >> On Mon, Aug 29, 2011 at 10:42 PM, Lukas Czerner <lczerner@redhat.com> wrote: >> > On Mon, 29 Aug 2011, Lin Ming wrote: >> > >> >> On Mon, Aug 29, 2011 at 7:56 PM, Lukas Czerner <lczerner@redhat.com> wrote: >> >> > >> >> > Regarding the atomic operations I do not think that implicit memory >> >> > barriers are needed here as atomic_dec_and_test() implies memory >> >> >> >> Which implicit memory barrier you are talking about? >> > >> > smp_mb() at both side of the operation as documented here in >> > Documentation/memory-barriers.txt >> >> Thanks for the info. >> >> But I don't follow you ... why that implicit memory barriers are NOT needed? >> > > Oh, I am sorry I have actually wanted to say that *explicit* memory > barriers are no needed in that case. Sorry for the confusion!
Make sense now :)
Thanks.
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