On Thu, Feb 13, 2025 at 06:17:49AM +0100, Christoph Hellwig wrote: > On Fri, Feb 07, 2025 at 09:52:31AM -0800, Darrick J. Wong wrote: > > On Thu, Feb 06, 2025 at 07:44:39AM +0100, Christoph Hellwig wrote: > > > For zoned file systems garbage collection (GC) has to take the iolock > > > and mmaplock after moving data to a new place to synchronize with > > > readers. This means waiting for garbage collection with the iolock can > > > deadlock. > > > > > > To avoid this, the worst case required blocks have to be reserved before > > > taking the iolock, which is done using a new RTAVAILABLE counter that > > > tracks blocks that are free to write into and don't require garbage > > > > Wasn't that in the last patch? Should this sentence move there? > > The last patch added the counter, it really should be here. Let me > reshuffle the patches a bit to make that happen. > > > > + if (flags & XFS_ZR_NOWAIT) > > > + return -EAGAIN; > > > + > > > + spin_lock(&zi->zi_reservation_lock); > > > + list_add_tail(&reservation.entry, &zi->zi_reclaim_reservations); > > > > I think you're supposed to have initialized reservation.entry already. > > What do you mean with that? I think the reservation was declared to be initialized as zeroes, but there was never an INIT_LIST_HEAD(&reservation.entry) to set the pointers to each other? > > > + int error; > > > + > > > + ASSERT(ac->reserved_blocks == 0); > > > + ASSERT(ac->open_zone == NULL); > > > + > > > + error = xfs_dec_freecounter(mp, XC_FREE_RTEXTENTS, count_fsb, > > > + flags & XFS_ZR_RESERVED); > > > + if (error == -ENOSPC && (flags & XFS_ZR_GREEDY) && count_fsb > 1) > > > + error = xfs_zoned_reserve_extents_greedy(ip, &count_fsb, flags); > > > > Overly long line. > > It's exactly 80 characters :) There are two things I'm bad at: off by one errors. --D
