On Thu, Dec 13 2012 at 3:19pm -0500, Joe Thornber <ejt@xxxxxxxxxx> wrote: > The deferred_set entries should not be incremented until the bio > prison cells are held. Otherwise quiescing a block for discard may > end up waiting for a bio that's held in the discard bios cell. This patch's subject and header needs help. We've already fixed the race with discards and normal bios in an earlier patch: https://www.redhat.com/archives/dm-devel/2012-December/msg00010.html This patch is purely about adapting dm-thin to use the new bio-prison interface where the memory is now passed in rather than using a mempool in bio-prison. Two preallocated cells are now included in struct thin_c; this allows the map function to not block performing allocations (we want to avoid the cell allocation that is done in bio_detain). The thin_c is allocated once in the constructor (thin_ctr). Because the thin_c is a shared resource, access to its cells must be serialized using a new spinlock. (NOTE: elevating the dm_bio_prison_cell structure from dm-bio-prison.c to dm-bio-prison.h really should be part of this patch -- rather than the previous patch). -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
