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Ilya Dryomov authored
This reverts commit 89baaa57. Dirty page throttling should be sufficient for us in the general case so there is no need to use __GFP_MEMALLOC - it would be needed only in the swap-over-rbd case, which we currently don't support. (It would probably take approximately the commit that is being reverted to add that support, but we would also need the "swap" option to distinguish from the general case and make sure swap ceph_client-s aren't shared with anything else.) See ceph-devel threads [1] and [2] for the details of why enabling pfmemalloc reserves for all cases is a bad thing. On top of potential system lockups related to drained emergency reserves, this turned out to cause ceph lockups in case peers are on the same host and communicating via loopback due to sk_filter() dropping pfmemalloc skbs on the receiving side because the receiving loopback socket is not tagged with SOCK_MEMALLOC. [1] "SOCK_MEMALLOC vs loopback" http://www.spinics.net/lists/ceph-devel/msg22998.html [2] "[PATCH] libceph: don't set memalloc flags in loopback case" http://www.spinics.net/lists/ceph-devel/msg23392.html Conflicts: net/ceph/messenger.c [ context: tcp_nodelay option ] Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Mel Gorman <mgorman@suse.de> Cc: Sage Weil <sage@redhat.com> Cc: stable@vger.kernel.org # 3.18+, needs backporting Signed-off-by:
Ilya Dryomov <idryomov@gmail.com> Acked-by:
Mike Christie <michaelc@cs.wisc.edu> Acked-by:
Mel Gorman <mgorman@suse.de>
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