From 4560e78f40cb55bd2ea8f1ef4001c5baa88531c7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Feb 2017 14:07:58 -0800 Subject: xfs: don't block the log commit handler for discards Instead we submit the discard requests and use another workqueue to release the extents from the extent busy list. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_log_cil.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 76 insertions(+), 8 deletions(-) (limited to 'fs/xfs/xfs_log_cil.c') diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c index a4ab192e1792..82f1cbcc4de1 100644 --- a/fs/xfs/xfs_log_cil.c +++ b/fs/xfs/xfs_log_cil.c @@ -30,6 +30,9 @@ #include "xfs_trans_priv.h" #include "xfs_log.h" #include "xfs_log_priv.h" +#include "xfs_trace.h" + +struct workqueue_struct *xfs_discard_wq; /* * Allocate a new ticket. Failing to get a new ticket makes it really hard to @@ -491,6 +494,75 @@ xlog_cil_free_logvec( } } +static void +xlog_discard_endio_work( + struct work_struct *work) +{ + struct xfs_cil_ctx *ctx = + container_of(work, struct xfs_cil_ctx, discard_endio_work); + struct xfs_mount *mp = ctx->cil->xc_log->l_mp; + + xfs_extent_busy_clear(mp, &ctx->busy_extents, false); + kmem_free(ctx); +} + +/* + * Queue up the actual completion to a thread to avoid IRQ-safe locking for + * pagb_lock. Note that we need a unbounded workqueue, otherwise we might + * get the execution delayed up to 30 seconds for weird reasons. + */ +static void +xlog_discard_endio( + struct bio *bio) +{ + struct xfs_cil_ctx *ctx = bio->bi_private; + + INIT_WORK(&ctx->discard_endio_work, xlog_discard_endio_work); + queue_work(xfs_discard_wq, &ctx->discard_endio_work); +} + +static void +xlog_discard_busy_extents( + struct xfs_mount *mp, + struct xfs_cil_ctx *ctx) +{ + struct list_head *list = &ctx->busy_extents; + struct xfs_extent_busy *busyp; + struct bio *bio = NULL; + struct blk_plug plug; + int error = 0; + + ASSERT(mp->m_flags & XFS_MOUNT_DISCARD); + + blk_start_plug(&plug); + list_for_each_entry(busyp, list, list) { + trace_xfs_discard_extent(mp, busyp->agno, busyp->bno, + busyp->length); + + error = __blkdev_issue_discard(mp->m_ddev_targp->bt_bdev, + XFS_AGB_TO_DADDR(mp, busyp->agno, busyp->bno), + XFS_FSB_TO_BB(mp, busyp->length), + GFP_NOFS, 0, &bio); + if (error && error != -EOPNOTSUPP) { + xfs_info(mp, + "discard failed for extent [0x%llx,%u], error %d", + (unsigned long long)busyp->bno, + busyp->length, + error); + break; + } + } + + if (bio) { + bio->bi_private = ctx; + bio->bi_end_io = xlog_discard_endio; + submit_bio(bio); + } else { + xlog_discard_endio_work(&ctx->discard_endio_work); + } + blk_finish_plug(&plug); +} + /* * Mark all items committed and clear busy extents. We free the log vector * chains in a separate pass so that we unpin the log items as quickly as @@ -525,14 +597,10 @@ xlog_cil_committed( xlog_cil_free_logvec(ctx->lv_chain); - if (!list_empty(&ctx->busy_extents)) { - ASSERT(mp->m_flags & XFS_MOUNT_DISCARD); - - xfs_discard_extents(mp, &ctx->busy_extents); - xfs_extent_busy_clear(mp, &ctx->busy_extents, false); - } - - kmem_free(ctx); + if (!list_empty(&ctx->busy_extents)) + xlog_discard_busy_extents(mp, ctx); + else + kmem_free(ctx); } /* -- cgit v1.2.3