[PATCH 6/7] xfs: remove efi_next_extent

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

As the new code shows much more clearly we always have a 1:1 relationship
between EFI and EFD items, and thus don't need to count the number of
extents that and EFD cancels out.  Thus we can remove the efi_next_extent
field and all logic related to it.

Also this makes clear that the only field we actually use in the EFD is
the efi_id, thus there's no need to even bother formatting the extents
into the EFD.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 fs/xfs/xfs_extfree_item.c |   37 ++++++++++---------------------------
 fs/xfs/xfs_extfree_item.h |    1 -
 fs/xfs/xfs_log_recover.c  |    2 +-
 fs/xfs/xfs_trans.h        |    2 +-
 4 files changed, 12 insertions(+), 30 deletions(-)

diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c
index 7ed0e01..da0ac7c 100644
--- a/fs/xfs/xfs_extfree_item.c
+++ b/fs/xfs/xfs_extfree_item.c
@@ -47,14 +47,17 @@ xfs_efi_item_free(
 }
 
 /*
+ * This is called by the efd item code below to release references to the given
+ * efi item.
+ *
  * Freeing the efi requires that we remove it from the AIL if it has already
  * been placed there. However, the EFI may not yet have been placed in the AIL
- * when called by xfs_efi_release() from EFD processing due to the ordering of
- * committed vs unpin operations in bulk insert operations. Hence the reference
- * count to ensure only the last caller frees the EFI.
+ * when called by xfs_efd_item_committed due to the ordering of committed vs
+ * unpin operations in bulk insert operations. Hence the reference count to
+ * ensure only the last caller frees the EFI.
  */
-STATIC void
-__xfs_efi_release(
+void
+xfs_efi_release(
        struct xfs_efi_log_item *efip)
 {
        struct xfs_ail          *ailp = efip->efi_item.li_ailp;
@@ -120,8 +123,6 @@ xfs_efi_item_format(
        elf->efi_id = efip->efi_id;
 
        for (free = efip->efi_flist.xbf_first; free; free = free->xbfi_next) {
-               atomic_inc(&efip->efi_next_extent);
-
                elf->efi_extents[e].ext_start = free->xbfi_startblock;
                elf->efi_extents[e].ext_len = free->xbfi_blockcount;
                e++;
@@ -161,7 +162,7 @@ xfs_efi_item_unpin(
                xfs_efi_item_free(efip);
                return;
        }
-       __xfs_efi_release(efip);
+       xfs_efi_release(efip);
 }
 
 /*
@@ -240,7 +241,6 @@ xfs_efi_init(
        efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
        xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
 
-       atomic_set(&efip->efi_next_extent, 0);
        atomic_set(&efip->efi_refcount, 2);
        efip->efi_id = (unsigned long)efip;
 
@@ -333,27 +333,10 @@ xfs_efi_item_from_disk(
                return EFSCORRUPTED;
        }
 
-       atomic_set(&efip->efi_next_extent, efip->efi_flist.xbf_count);
        *efipp = efip;
        return 0;
 }
 
-
-/*
- * This is called by the efd item code below to release references to the given
- * efi item.  Each efd calls this with the number of extents that it has
- * logged, and when the sum of these reaches the total number of extents logged
- * by this efi item we can free the efi item.
- */
-void
-xfs_efi_release(xfs_efi_log_item_t     *efip,
-               uint                    nextents)
-{
-       ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
-       if (atomic_sub_and_test(nextents, &efip->efi_next_extent))
-               __xfs_efi_release(efip);
-}
-
 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
 {
        return container_of(lip, struct xfs_efd_log_item, efd_item);
@@ -479,7 +462,7 @@ xfs_efd_item_committed(
         * EFI got unpinned and freed before the EFD got aborted.
         */
        if (!(lip->li_flags & XFS_LI_ABORTED))
-               xfs_efi_release(efdp->efd_efip, efdp->efd_flist.xbf_count);
+               xfs_efi_release(efdp->efd_efip);
 
        kmem_zone_free(xfs_efd_zone, efdp);
        return (xfs_lsn_t)-1;
diff --git a/fs/xfs/xfs_extfree_item.h b/fs/xfs/xfs_extfree_item.h
index 724a7e4..e658d42 100644
--- a/fs/xfs/xfs_extfree_item.h
+++ b/fs/xfs/xfs_extfree_item.h
@@ -46,7 +46,6 @@ struct kmem_zone;
 typedef struct xfs_efi_log_item {
        xfs_log_item_t          efi_item;
        atomic_t                efi_refcount;
-       atomic_t                efi_next_extent;
        unsigned long           efi_flags;      /* misc flags */
        struct xfs_bmap_free    efi_flist;
        unsigned long           efi_id;
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 61e8587..b679a0b 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -3641,7 +3641,7 @@ xlog_recover_process_efi(
                         * memory associated with it.
                         */
                        set_bit(XFS_EFI_RECOVERED, &efip->efi_flags);
-                       xfs_efi_release(efip, efip->efi_flist.xbf_count);
+                       xfs_efi_release(efip);
                        return XFS_ERROR(EIO);
                }
        }
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index f6b4cf0..6723157 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -216,7 +216,7 @@ void                xfs_trans_ichgtime(struct xfs_trans *, 
struct xfs_inode *, int);
 void           xfs_trans_ijoin(struct xfs_trans *, struct xfs_inode *, uint);
 void           xfs_trans_log_buf(xfs_trans_t *, struct xfs_buf *, uint, uint);
 void           xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint);
-void           xfs_efi_release(struct xfs_efi_log_item *, uint);
+void           xfs_efi_release(struct xfs_efi_log_item *);
 struct xfs_efi_log_item *xfs_trans_log_efi(struct xfs_trans *,
                        struct xfs_bmap_free *);
 struct xfs_efd_log_item        *xfs_trans_log_efd(struct xfs_trans *,
-- 
1.7.10.4