[XFS] split xfs_icsb_balance_counter

Add an xfs_icsb_balance_counter_locked for the case where mp->m_sb_lock is
already locked.

SGI-PV: 976035
SGI-Modid: xfs-linux-melb:xfs-kern:30918a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

fs/xfs/xfs_mount.c

@@ -54,7 +54,9 @@ STATIC void	xfs_unmountfs_wait(xfs_mount_t *);
 #ifdef HAVE_PERCPU_SB
 STATIC void	xfs_icsb_destroy_counters(xfs_mount_t *);
 STATIC void	xfs_icsb_balance_counter(xfs_mount_t *, xfs_sb_field_t,
-						int, int);
+						int);
+STATIC void	xfs_icsb_balance_counter_locked(xfs_mount_t *, xfs_sb_field_t,
+						int);
 STATIC int	xfs_icsb_modify_counters(xfs_mount_t *, xfs_sb_field_t,
 						int64_t, int);
 STATIC void	xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
@@ -62,7 +64,8 @@ STATIC void	xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
 #else
 
 #define xfs_icsb_destroy_counters(mp)			do { } while (0)
-#define xfs_icsb_balance_counter(mp, a, b, c)		do { } while (0)
+#define xfs_icsb_balance_counter(mp, a, b)		do { } while (0)
+#define xfs_icsb_balance_counter_locked(mp, a, b)	do { } while (0)
 #define xfs_icsb_modify_counters(mp, a, b, c)		do { } while (0)
 
 #endif
@@ -2024,9 +2027,9 @@ xfs_icsb_cpu_notify(
 	case CPU_ONLINE:
 	case CPU_ONLINE_FROZEN:
 		xfs_icsb_lock(mp);
-		xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0, 0);
-		xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0, 0);
-		xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0, 0);
+		xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
+		xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
+		xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
 		xfs_icsb_unlock(mp);
 		break;
 	case CPU_DEAD:
@@ -2046,12 +2049,9 @@ xfs_icsb_cpu_notify(
 
 		memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
 
-		xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT,
-					 XFS_ICSB_SB_LOCKED, 0);
-		xfs_icsb_balance_counter(mp, XFS_SBS_IFREE,
-					 XFS_ICSB_SB_LOCKED, 0);
-		xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS,
-					 XFS_ICSB_SB_LOCKED, 0);
+		xfs_icsb_balance_counter_locked(mp, XFS_SBS_ICOUNT, 0);
+		xfs_icsb_balance_counter_locked(mp, XFS_SBS_IFREE, 0);
+		xfs_icsb_balance_counter_locked(mp, XFS_SBS_FDBLOCKS, 0);
 		spin_unlock(&mp->m_sb_lock);
 		xfs_icsb_unlock(mp);
 		break;
@@ -2103,9 +2103,9 @@ xfs_icsb_reinit_counters(
 	 * initial balance kicks us off correctly
 	 */
 	mp->m_icsb_counters = -1;
-	xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0, 0);
-	xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0, 0);
-	xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0, 0);
+	xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
+	xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
+	xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
 	xfs_icsb_unlock(mp);
 }
 
@@ -2325,19 +2325,15 @@ xfs_icsb_sync_counters(
 #define XFS_ICSB_FDBLK_CNTR_REENABLE(mp) \
 		(uint64_t)(512 + XFS_ALLOC_SET_ASIDE(mp))
 STATIC void
-xfs_icsb_balance_counter(
+xfs_icsb_balance_counter_locked(
 	xfs_mount_t	*mp,
 	xfs_sb_field_t  field,
-	int		flags,
 	int		min_per_cpu)
 {
 	uint64_t	count, resid;
 	int		weight = num_online_cpus();
 	uint64_t	min = (uint64_t)min_per_cpu;
 
-	if (!(flags & XFS_ICSB_SB_LOCKED))
-		spin_lock(&mp->m_sb_lock);
-
 	/* disable counter and sync counter */
 	xfs_icsb_disable_counter(mp, field);
 
@@ -2347,19 +2343,19 @@ xfs_icsb_balance_counter(
 		count = mp->m_sb.sb_icount;
 		resid = do_div(count, weight);
 		if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
-			goto out;
+			return;
 		break;
 	case XFS_SBS_IFREE:
 		count = mp->m_sb.sb_ifree;
 		resid = do_div(count, weight);
 		if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
-			goto out;
+			return;
 		break;
 	case XFS_SBS_FDBLOCKS:
 		count = mp->m_sb.sb_fdblocks;
 		resid = do_div(count, weight);
 		if (count < max(min, XFS_ICSB_FDBLK_CNTR_REENABLE(mp)))
-			goto out;
+			return;
 		break;
 	default:
 		BUG();
@@ -2368,8 +2364,16 @@ xfs_icsb_balance_counter(
 	}
 
 	xfs_icsb_enable_counter(mp, field, count, resid);
-out:
-	if (!(flags & XFS_ICSB_SB_LOCKED))
+}
+
+STATIC void
+xfs_icsb_balance_counter(
+	xfs_mount_t	*mp,
+	xfs_sb_field_t  fields,
+	int		min_per_cpu)
+{
+	spin_lock(&mp->m_sb_lock);
+	xfs_icsb_balance_counter_locked(mp, fields, min_per_cpu);
 	spin_unlock(&mp->m_sb_lock);
 }
 
@@ -2477,7 +2481,7 @@ xfs_icsb_modify_counters(
 	 * we are done.
 	 */
 	if (ret != ENOSPC)
-		xfs_icsb_balance_counter(mp, field, 0, 0);
+		xfs_icsb_balance_counter(mp, field, 0);
 	xfs_icsb_unlock(mp);
 	return ret;
 
@@ -2501,7 +2505,7 @@ xfs_icsb_modify_counters(
 	 * will either succeed through the fast path or slow path without
 	 * another balance operation being required.
 	 */
-	xfs_icsb_balance_counter(mp, field, 0, delta);
+	xfs_icsb_balance_counter(mp, field, delta);
 	xfs_icsb_unlock(mp);
 	goto again;
 }