xfs: do not use xfs_mod_incore_sb_batch for per-cpu counters
Update the per-cpu counters manually in xfs_trans_unreserve_and_mod_sb
and remove support for per-cpu counters from xfs_mod_incore_sb_batch
to simplify it. And added benefit is that we don't have to take
m_sb_lock for transactions that only modify per-cpu counters.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 20c67ff..00538b7 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -1856,98 +1856,54 @@
}
/*
- * xfs_mod_incore_sb_batch() is used to change more than one field
- * in the in-core superblock structure at a time. This modification
- * is protected by a lock internal to this module. The fields and
- * changes to those fields are specified in the array of xfs_mod_sb
- * structures passed in.
+ * Change more than one field in the in-core superblock structure at a time.
*
- * Either all of the specified deltas will be applied or none of
- * them will. If any modified field dips below 0, then all modifications
- * will be backed out and EINVAL will be returned.
+ * The fields and changes to those fields are specified in the array of
+ * xfs_mod_sb structures passed in. Either all of the specified deltas
+ * will be applied or none of them will. If any modified field dips below 0,
+ * then all modifications will be backed out and EINVAL will be returned.
+ *
+ * Note that this function may not be used for the superblock values that
+ * are tracked with the in-memory per-cpu counters - a direct call to
+ * xfs_icsb_modify_counters is required for these.
*/
int
-xfs_mod_incore_sb_batch(xfs_mount_t *mp, xfs_mod_sb_t *msb, uint nmsb, int rsvd)
+xfs_mod_incore_sb_batch(
+ struct xfs_mount *mp,
+ xfs_mod_sb_t *msb,
+ uint nmsb,
+ int rsvd)
{
- int status=0;
- xfs_mod_sb_t *msbp;
+ xfs_mod_sb_t *msbp = &msb[0];
+ int error = 0;
/*
- * Loop through the array of mod structures and apply each
- * individually. If any fail, then back out all those
- * which have already been applied. Do all of this within
- * the scope of the m_sb_lock so that all of the changes will
- * be atomic.
+ * Loop through the array of mod structures and apply each individually.
+ * If any fail, then back out all those which have already been applied.
+ * Do all of this within the scope of the m_sb_lock so that all of the
+ * changes will be atomic.
*/
spin_lock(&mp->m_sb_lock);
- msbp = &msb[0];
for (msbp = &msbp[0]; msbp < (msb + nmsb); msbp++) {
- /*
- * Apply the delta at index n. If it fails, break
- * from the loop so we'll fall into the undo loop
- * below.
- */
- switch (msbp->msb_field) {
-#ifdef HAVE_PERCPU_SB
- case XFS_SBS_ICOUNT:
- case XFS_SBS_IFREE:
- case XFS_SBS_FDBLOCKS:
- spin_unlock(&mp->m_sb_lock);
- status = xfs_icsb_modify_counters(mp,
- msbp->msb_field,
- msbp->msb_delta, rsvd);
- spin_lock(&mp->m_sb_lock);
- break;
-#endif
- default:
- status = xfs_mod_incore_sb_unlocked(mp,
- msbp->msb_field,
- msbp->msb_delta, rsvd);
- break;
- }
+ ASSERT(msbp->msb_field < XFS_SBS_ICOUNT ||
+ msbp->msb_field > XFS_SBS_FDBLOCKS);
- if (status != 0) {
- break;
- }
- }
-
- /*
- * If we didn't complete the loop above, then back out
- * any changes made to the superblock. If you add code
- * between the loop above and here, make sure that you
- * preserve the value of status. Loop back until
- * we step below the beginning of the array. Make sure
- * we don't touch anything back there.
- */
- if (status != 0) {
- msbp--;
- while (msbp >= msb) {
- switch (msbp->msb_field) {
-#ifdef HAVE_PERCPU_SB
- case XFS_SBS_ICOUNT:
- case XFS_SBS_IFREE:
- case XFS_SBS_FDBLOCKS:
- spin_unlock(&mp->m_sb_lock);
- status = xfs_icsb_modify_counters(mp,
- msbp->msb_field,
- -(msbp->msb_delta),
- rsvd);
- spin_lock(&mp->m_sb_lock);
- break;
-#endif
- default:
- status = xfs_mod_incore_sb_unlocked(mp,
- msbp->msb_field,
- -(msbp->msb_delta),
- rsvd);
- break;
- }
- ASSERT(status == 0);
- msbp--;
- }
+ error = xfs_mod_incore_sb_unlocked(mp, msbp->msb_field,
+ msbp->msb_delta, rsvd);
+ if (error)
+ goto unwind;
}
spin_unlock(&mp->m_sb_lock);
- return status;
+ return 0;
+
+unwind:
+ while (--msbp >= msb) {
+ error = xfs_mod_incore_sb_unlocked(mp, msbp->msb_field,
+ -msbp->msb_delta, rsvd);
+ ASSERT(error == 0);
+ }
+ spin_unlock(&mp->m_sb_lock);
+ return error;
}
/*
@@ -2478,7 +2434,7 @@
spin_unlock(&mp->m_sb_lock);
}
-STATIC int
+int
xfs_icsb_modify_counters(
xfs_mount_t *mp,
xfs_sb_field_t field,