Re: [PATCH 08/22] xfs: pass perags through to the busy extent code

Darrick J. Wong
2021-05-12T22:42:56Z

On Thu, May 06, 2021 at 05:20:40PM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@redhat.com>
>
> All of the callers of the busy extent API either have perag
> references available to use so we can pass a perag to the busy
> extent functions rather than having them have to do unnecessary
> lookups.
>
> Signed-off-by: Dave Chinner <dchinner@redhat.com>

I began to wonder during this patch if the cur->bc_ag ought to hold a
reference to the perag struct instead of the agno, but I guess that
makes little difference since we still have to attach the AG header
buffer to the cursor.

Just thought I'd mention that in case anyone else was thinking along the
same lines, but I don't expect to see such a ch{ange,urn} in this
series, so:

Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
> fs/xfs/libxfs/xfs_alloc.c | 37 +++++++++++++++++----------------
> fs/xfs/libxfs/xfs_alloc.h | 2 +-
> fs/xfs/libxfs/xfs_alloc_btree.c | 5 ++---
> fs/xfs/libxfs/xfs_rmap.c | 32 ++++++++++++++++------------
> fs/xfs/libxfs/xfs_rmap_btree.c | 7 +++----
> fs/xfs/scrub/repair.c | 4 ++--
> fs/xfs/xfs_discard.c | 2 +-
> fs/xfs/xfs_extent_busy.c | 24 ++++++---------------
> fs/xfs/xfs_extent_busy.h | 7 ++++---
> 9 files changed, 57 insertions(+), 63 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> index dc2b77829915..ce31c00dbf6f 100644
> --- a/fs/xfs/libxfs/xfs_alloc.c
> +++ b/fs/xfs/libxfs/xfs_alloc.c
> @@ -1063,7 +1063,7 @@ xfs_alloc_ag_vextent_small(
> if (fbno == NULLAGBLOCK)
> goto out;
>
> - xfs_extent_busy_reuse(args->mp, args->agno, fbno, 1,
> + xfs_extent_busy_reuse(args->mp, args->pag, fbno, 1,
> (args->datatype & XFS_ALLOC_NOBUSY));
>
> if (args->datatype & XFS_ALLOC_USERDATA) {
> @@ -1178,7 +1178,7 @@ xfs_alloc_ag_vextent(
> if (error)
> return error;
>
> - ASSERT(!xfs_extent_busy_search(args->mp, args->agno,
> + ASSERT(!xfs_extent_busy_search(args->mp, args->pag,
> args->agbno, args->len));
> }
>
> @@ -3292,7 +3292,7 @@ xfs_alloc_vextent(
> int
> xfs_free_extent_fix_freelist(
> struct xfs_trans *tp,
> - xfs_agnumber_t agno,
> + struct xfs_perag *pag,
> struct xfs_buf **agbp)
> {
> struct xfs_alloc_arg args;
> @@ -3301,7 +3301,8 @@ xfs_free_extent_fix_freelist(
> memset(&args, 0, sizeof(struct xfs_alloc_arg));
> args.tp = tp;
> args.mp = tp->t_mountp;
> - args.agno = agno;
> + args.agno = pag->pag_agno;
> + args.pag = pag;
>
> /*
> * validate that the block number is legal - the enables us to detect
> @@ -3310,17 +3311,12 @@ xfs_free_extent_fix_freelist(
> if (args.agno >= args.mp->m_sb.sb_agcount)
> return -EFSCORRUPTED;
>
> - args.pag = xfs_perag_get(args.mp, args.agno);
> - ASSERT(args.pag);
> -
> error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
> if (error)
> - goto out;
> + return error;
>
> *agbp = args.agbp;
> -out:
> - xfs_perag_put(args.pag);
> - return error;
> + return 0;
> }
>
> /*
> @@ -3344,6 +3340,7 @@ __xfs_free_extent(
> struct xfs_agf *agf;
> int error;
> unsigned int busy_flags = 0;
> + struct xfs_perag *pag;
>
> ASSERT(len != 0);
> ASSERT(type != XFS_AG_RESV_AGFL);
> @@ -3352,33 +3349,37 @@ __xfs_free_extent(
> XFS_ERRTAG_FREE_EXTENT))
> return -EIO;
>
> - error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
> + pag = xfs_perag_get(mp, agno);
> + error = xfs_free_extent_fix_freelist(tp, pag, &agbp);
> if (error)
> - return error;
> + goto err;
> agf = agbp->b_addr;
>
> if (XFS_IS_CORRUPT(mp, agbno >= mp->m_sb.sb_agblocks)) {
> error = -EFSCORRUPTED;
> - goto err;
> + goto err_release;
> }
>
> /* validate the extent size is legal now we have the agf locked */
> if (XFS_IS_CORRUPT(mp, agbno + len > be32_to_cpu(agf->agf_length))) {
> error = -EFSCORRUPTED;
> - goto err;
> + goto err_release;
> }
>
> error = xfs_free_ag_extent(tp, agbp, agno, agbno, len, oinfo, type);
> if (error)
> - goto err;
> + goto err_release;
>
> if (skip_discard)
> busy_flags |= XFS_EXTENT_BUSY_SKIP_DISCARD;
> - xfs_extent_busy_insert(tp, agno, agbno, len, busy_flags);
> + xfs_extent_busy_insert(tp, pag, agbno, len, busy_flags);
> + xfs_perag_put(pag);
> return 0;
>
> -err:
> +err_release:
> xfs_trans_brelse(tp, agbp);
> +err:
> + xfs_perag_put(pag);
> return error;
> }
>
> diff --git a/fs/xfs/libxfs/xfs_alloc.h b/fs/xfs/libxfs/xfs_alloc.h
> index a4427c5775c2..e30900b6f8ba 100644
> --- a/fs/xfs/libxfs/xfs_alloc.h
> +++ b/fs/xfs/libxfs/xfs_alloc.h
> @@ -214,7 +214,7 @@ int xfs_alloc_read_agfl(struct xfs_mount *mp, struct xfs_trans *tp,
> int xfs_free_agfl_block(struct xfs_trans *, xfs_agnumber_t, xfs_agblock_t,
> struct xfs_buf *, struct xfs_owner_info *);
> int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
> -int xfs_free_extent_fix_freelist(struct xfs_trans *tp, xfs_agnumber_t agno,
> +int xfs_free_extent_fix_freelist(struct xfs_trans *tp, struct xfs_perag *pag,
> struct xfs_buf **agbp);
>
> xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
> diff --git a/fs/xfs/libxfs/xfs_alloc_btree.c b/fs/xfs/libxfs/xfs_alloc_btree.c
> index a540b6e799e0..19fdf87e86b9 100644
> --- a/fs/xfs/libxfs/xfs_alloc_btree.c
> +++ b/fs/xfs/libxfs/xfs_alloc_btree.c
> @@ -72,7 +72,7 @@ xfs_allocbt_alloc_block(
> }
>
> atomic64_inc(&cur->bc_mp->m_allocbt_blks);
> - xfs_extent_busy_reuse(cur->bc_mp, cur->bc_ag.agno, bno, 1, false);
> + xfs_extent_busy_reuse(cur->bc_mp, cur->bc_ag.agbp->b_pag, bno, 1, false);
>
> new->s = cpu_to_be32(bno);
>
> @@ -86,7 +86,6 @@ xfs_allocbt_free_block(
> struct xfs_buf *bp)
> {
> struct xfs_buf *agbp = cur->bc_ag.agbp;
> - struct xfs_agf *agf = agbp->b_addr;
> xfs_agblock_t bno;
> int error;
>
> @@ -96,7 +95,7 @@ xfs_allocbt_free_block(
> return error;
>
> atomic64_dec(&cur->bc_mp->m_allocbt_blks);
> - xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
> + xfs_extent_busy_insert(cur->bc_tp, agbp->b_pag, bno, 1,
> XFS_EXTENT_BUSY_SKIP_DISCARD);
> return 0;
> }
> diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c
> index 61e8f10436ac..1d0a6b686eea 100644
> --- a/fs/xfs/libxfs/xfs_rmap.c
> +++ b/fs/xfs/libxfs/xfs_rmap.c
> @@ -11,6 +11,7 @@
> #include "xfs_trans_resv.h"
> #include "xfs_bit.h"
> #include "xfs_mount.h"
> +#include "xfs_sb.h"
> #include "xfs_defer.h"
> #include "xfs_btree.h"
> #include "xfs_trans.h"
> @@ -2363,31 +2364,32 @@ xfs_rmap_finish_one(
> struct xfs_btree_cur **pcur)
> {
> struct xfs_mount *mp = tp->t_mountp;
> + struct xfs_perag *pag;
> struct xfs_btree_cur *rcur;
> struct xfs_buf *agbp = NULL;
> int error = 0;
> - xfs_agnumber_t agno;
> struct xfs_owner_info oinfo;
> xfs_agblock_t bno;
> bool unwritten;
>
> - agno = XFS_FSB_TO_AGNO(mp, startblock);
> - ASSERT(agno != NULLAGNUMBER);
> + pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, startblock));
> bno = XFS_FSB_TO_AGBNO(mp, startblock);
>
> - trace_xfs_rmap_deferred(mp, agno, type, bno, owner, whichfork,
> + trace_xfs_rmap_deferred(mp, pag->pag_agno, type, bno, owner, whichfork,
> startoff, blockcount, state);
>
> - if (XFS_TEST_ERROR(false, mp,
> - XFS_ERRTAG_RMAP_FINISH_ONE))
> - return -EIO;
> + if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_RMAP_FINISH_ONE)) {
> + error = -EIO;
> + goto out_drop;
> + }
> +
>
> /*
> * If we haven't gotten a cursor or the cursor AG doesn't match
> * the startblock, get one now.
> */
> rcur = *pcur;
> - if (rcur != NULL && rcur->bc_ag.agno != agno) {
> + if (rcur != NULL && rcur->bc_ag.agno != pag->pag_agno) {
> xfs_rmap_finish_one_cleanup(tp, rcur, 0);
> rcur = NULL;
> *pcur = NULL;
> @@ -2398,13 +2400,15 @@ xfs_rmap_finish_one(
> * rmapbt, because a shape change could cause us to
> * allocate blocks.
> */
> - error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
> + error = xfs_free_extent_fix_freelist(tp, pag, &agbp);
> if (error)
> - return error;
> - if (XFS_IS_CORRUPT(tp->t_mountp, !agbp))
> - return -EFSCORRUPTED;
> + goto out_drop;
> + if (XFS_IS_CORRUPT(tp->t_mountp, !agbp)) {
> + error = -EFSCORRUPTED;
> + goto out_drop;
> + }
>
> - rcur = xfs_rmapbt_init_cursor(mp, tp, agbp, agno);
> + rcur = xfs_rmapbt_init_cursor(mp, tp, agbp, pag->pag_agno);
> }
> *pcur = rcur;
>
> @@ -2442,6 +2446,8 @@ xfs_rmap_finish_one(
> ASSERT(0);
> error = -EFSCORRUPTED;
> }
> +out_drop:
> + xfs_perag_put(pag);
> return error;
> }
>
> diff --git a/fs/xfs/libxfs/xfs_rmap_btree.c b/fs/xfs/libxfs/xfs_rmap_btree.c
> index f1fee42dda2d..46a5295ecf35 100644
> --- a/fs/xfs/libxfs/xfs_rmap_btree.c
> +++ b/fs/xfs/libxfs/xfs_rmap_btree.c
> @@ -100,8 +100,7 @@ xfs_rmapbt_alloc_block(
> return 0;
> }
>
> - xfs_extent_busy_reuse(cur->bc_mp, cur->bc_ag.agno, bno, 1,
> - false);
> + xfs_extent_busy_reuse(cur->bc_mp, agbp->b_pag, bno, 1, false);
>
> new->s = cpu_to_be32(bno);
> be32_add_cpu(&agf->agf_rmap_blocks, 1);
> @@ -133,10 +132,10 @@ xfs_rmapbt_free_block(
> if (error)
> return error;
>
> - xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
> + pag = cur->bc_ag.agbp->b_pag;
> + xfs_extent_busy_insert(cur->bc_tp, pag, bno, 1,
> XFS_EXTENT_BUSY_SKIP_DISCARD);
>
> - pag = cur->bc_ag.agbp->b_pag;
> xfs_ag_resv_free_extent(pag, XFS_AG_RESV_RMAPBT, NULL, 1);
> return 0;
> }
> diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
> index 1308b62a8170..6b62872c4d10 100644
> --- a/fs/xfs/scrub/repair.c
> +++ b/fs/xfs/scrub/repair.c
> @@ -304,7 +304,7 @@ xrep_alloc_ag_block(
> return error;
> if (bno == NULLAGBLOCK)
> return -ENOSPC;
> - xfs_extent_busy_reuse(sc->mp, sc->sa.agno, bno,
> + xfs_extent_busy_reuse(sc->mp, sc->sa.pag, bno,
> 1, false);
> *fsbno = XFS_AGB_TO_FSB(sc->mp, sc->sa.agno, bno);
> if (resv == XFS_AG_RESV_RMAPBT)
> @@ -519,7 +519,7 @@ xrep_put_freelist(
> agbno, 0);
> if (error)
> return error;
> - xfs_extent_busy_insert(sc->tp, sc->sa.agno, agbno, 1,
> + xfs_extent_busy_insert(sc->tp, sc->sa.pag, agbno, 1,
> XFS_EXTENT_BUSY_SKIP_DISCARD);
>
> return 0;
> diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
> index 3bf6dba1a040..972864250bd2 100644
> --- a/fs/xfs/xfs_discard.c
> +++ b/fs/xfs/xfs_discard.c
> @@ -108,7 +108,7 @@ xfs_trim_extents(
> * If any blocks in the range are still busy, skip the
> * discard and try again the next time.
> */
> - if (xfs_extent_busy_search(mp, agno, fbno, flen)) {
> + if (xfs_extent_busy_search(mp, pag, fbno, flen)) {
> trace_xfs_discard_busy(mp, agno, fbno, flen);
> goto next_extent;
> }
> diff --git a/fs/xfs/xfs_extent_busy.c b/fs/xfs/xfs_extent_busy.c
> index 6af0b5a1c7b0..a0ea63fcc50d 100644
> --- a/fs/xfs/xfs_extent_busy.c
> +++ b/fs/xfs/xfs_extent_busy.c
> @@ -22,28 +22,26 @@
> void
> xfs_extent_busy_insert(
> struct xfs_trans *tp,
> - xfs_agnumber_t agno,
> + struct xfs_perag *pag,
> xfs_agblock_t bno,
> xfs_extlen_t len,
> unsigned int flags)
> {
> struct xfs_extent_busy *new;
> struct xfs_extent_busy *busyp;
> - struct xfs_perag *pag;
> struct rb_node **rbp;
> struct rb_node *parent = NULL;
>
> new = kmem_zalloc(sizeof(struct xfs_extent_busy), 0);
> - new->agno = agno;
> + new->agno = pag->pag_agno;
> new->bno = bno;
> new->length = len;
> INIT_LIST_HEAD(&new->list);
> new->flags = flags;
>
> /* trace before insert to be able to see failed inserts */
> - trace_xfs_extent_busy(tp->t_mountp, agno, bno, len);
> + trace_xfs_extent_busy(tp->t_mountp, pag->pag_agno, bno, len);
>
> - pag = xfs_perag_get(tp->t_mountp, new->agno);
> spin_lock(&pag->pagb_lock);
> rbp = &pag->pagb_tree.rb_node;
> while (*rbp) {
> @@ -66,7 +64,6 @@ xfs_extent_busy_insert(
>
> list_add(&new->list, &tp->t_busy);
> spin_unlock(&pag->pagb_lock);
> - xfs_perag_put(pag);
> }
>
> /*
> @@ -81,21 +78,17 @@ xfs_extent_busy_insert(
> int
> xfs_extent_busy_search(
> struct xfs_mount *mp,
> - xfs_agnumber_t agno,
> + struct xfs_perag *pag,
> xfs_agblock_t bno,
> xfs_extlen_t len)
> {
> - struct xfs_perag *pag;
> struct rb_node *rbp;
> struct xfs_extent_busy *busyp;
> int match = 0;
>
> - pag = xfs_perag_get(mp, agno);
> + /* find closest start bno overlap */
> spin_lock(&pag->pagb_lock);
> -
> rbp = pag->pagb_tree.rb_node;
> -
> - /* find closest start bno overlap */
> while (rbp) {
> busyp = rb_entry(rbp, struct xfs_extent_busy, rb_node);
> if (bno < busyp->bno) {
> @@ -115,7 +108,6 @@ xfs_extent_busy_search(
> }
> }
> spin_unlock(&pag->pagb_lock);
> - xfs_perag_put(pag);
> return match;
> }
>
> @@ -281,17 +273,14 @@ xfs_extent_busy_update_extent(
> void
> xfs_extent_busy_reuse(
> struct xfs_mount *mp,
> - xfs_agnumber_t agno,
> + struct xfs_perag *pag,
> xfs_agblock_t fbno,
> xfs_extlen_t flen,
> bool userdata)
> {
> - struct xfs_perag *pag;
> struct rb_node *rbp;
>
> ASSERT(flen > 0);
> -
> - pag = xfs_perag_get(mp, agno);
> spin_lock(&pag->pagb_lock);
> restart:
> rbp = pag->pagb_tree.rb_node;
> @@ -314,7 +303,6 @@ xfs_extent_busy_reuse(
> goto restart;
> }
> spin_unlock(&pag->pagb_lock);
> - xfs_perag_put(pag);
> }
>
> /*
> diff --git a/fs/xfs/xfs_extent_busy.h b/fs/xfs/xfs_extent_busy.h
> index 990ab3891971..8031617bb6ef 100644
> --- a/fs/xfs/xfs_extent_busy.h
> +++ b/fs/xfs/xfs_extent_busy.h
> @@ -9,6 +9,7 @@
> #define __XFS_EXTENT_BUSY_H__
>
> struct xfs_mount;
> +struct xfs_perag;
> struct xfs_trans;
> struct xfs_alloc_arg;
>
> @@ -31,7 +32,7 @@ struct xfs_extent_busy {
> };
>
> void
> -xfs_extent_busy_insert(struct xfs_trans *tp, xfs_agnumber_t agno,
> +xfs_extent_busy_insert(struct xfs_trans *tp, struct xfs_perag *pag,
> xfs_agblock_t bno, xfs_extlen_t len, unsigned int flags);
>
> void
> @@ -39,11 +40,11 @@ xfs_extent_busy_clear(struct xfs_mount *mp, struct list_head *list,
> bool do_discard);
>
> int
> -xfs_extent_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
> +xfs_extent_busy_search(struct xfs_mount *mp, struct xfs_perag *pag,
> xfs_agblock_t bno, xfs_extlen_t len);
>
> void
> -xfs_extent_busy_reuse(struct xfs_mount *mp, xfs_agnumber_t agno,
> +xfs_extent_busy_reuse(struct xfs_mount *mp, struct xfs_perag *pag,
> xfs_agblock_t fbno, xfs_extlen_t flen, bool userdata);
>
> bool
> --
> 2.31.1
>