[PATCH 4/7] xfs: Remove icsb infrastructure

Dave Chinner
2015-02-04T20:54:34Z

From: Dave Chinner <dchinner@redhat.com>

Now that the in-core superblock infrastructure has been replaced with
generic per-cpu counters, we don't need it anymore. Nuke it from
orbit so we are sure that it won't haunt us again...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/libxfs/xfs_sb.c | 8 +-
fs/xfs/xfs_fsops.c | 2 -
fs/xfs/xfs_iomap.c | 1 -
fs/xfs/xfs_linux.h | 9 -
fs/xfs/xfs_log_recover.c | 4 +-
fs/xfs/xfs_mount.c | 516 +----------------------------------------------
fs/xfs/xfs_mount.h | 67 ------
fs/xfs/xfs_super.c | 84 ++++++--
fs/xfs/xfs_super.h | 2 +
9 files changed, 72 insertions(+), 621 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index 31a3e97..a270095 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -743,17 +743,15 @@ xfs_initialize_perag_data(
btree += pag->pagf_btreeblks;
xfs_perag_put(pag);
}
- /*
- * Overwrite incore superblock counters with just-read data
- */
+
+ /* Overwrite incore superblock counters with just-read data */
spin_lock(&mp->m_sb_lock);
sbp->sb_ifree = ifree;
sbp->sb_icount = ialloc;
sbp->sb_fdblocks = bfree + bfreelst + btree;
spin_unlock(&mp->m_sb_lock);

- /* Fixup the per-cpu counters as well. */
- xfs_icsb_reinit_counters(mp);
+ xfs_reinit_percpu_counters(mp);

return 0;
}
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index fed97a9..a45c82b4 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -630,7 +630,6 @@ xfs_fs_counts(
xfs_mount_t *mp,
xfs_fsop_counts_t *cnt)
{
- xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
cnt->allocino = percpu_counter_read_positive(&mp->m_icount);
cnt->freeino = percpu_counter_read_positive(&mp->m_ifree);
cnt->freedata = percpu_counter_read_positive(&mp->m_fdblocks) -
@@ -694,7 +693,6 @@ xfs_reserve_blocks(
*/
retry:
spin_lock(&mp->m_sb_lock);
- xfs_icsb_sync_counters_locked(mp, 0);

/*
* If our previous reservation was larger than the current value,
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 205b948..38e633b 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -460,7 +460,6 @@ xfs_iomap_prealloc_size(
alloc_blocks = XFS_FILEOFF_MIN(roundup_pow_of_two(MAXEXTLEN),
alloc_blocks);

- xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
freesp = percpu_counter_read_positive(&mp->m_fdblocks);
if (freesp < mp->m_low_space[XFS_LOWSP_5_PCNT]) {
shift = 2;
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index c31d2c2..7c7842c 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -116,15 +116,6 @@ typedef __uint64_t __psunsigned_t;
#undef XFS_NATIVE_HOST
#endif

-/*
- * Feature macros (disable/enable)
- */
-#ifdef CONFIG_SMP
-#define HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */
-#else
-#undef HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */
-#endif
-
#define irix_sgid_inherit xfs_params.sgid_inherit.val
#define irix_symlink_mode xfs_params.symlink_mode.val
#define xfs_panic_mask xfs_params.panic_mask.val
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index a5a945f..4f5784f 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -4463,10 +4463,10 @@ xlog_do_recover(
xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
ASSERT(sbp->sb_magicnum == XFS_SB_MAGIC);
ASSERT(xfs_sb_good_version(sbp));
+ xfs_reinit_percpu_counters(log->l_mp);
+
xfs_buf_relse(bp);

- /* We've re-read the superblock so re-initialize per-cpu counters */
- xfs_icsb_reinit_counters(log->l_mp);

xlog_recover_check_summary(log);

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 9e433b2..1d26200 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -43,18 +43,6 @@
#include "xfs_sysfs.h"

-#ifdef HAVE_PERCPU_SB
-STATIC void xfs_icsb_balance_counter(xfs_mount_t *, xfs_sb_field_t,
- int);
-STATIC void xfs_icsb_balance_counter_locked(xfs_mount_t *, xfs_sb_field_t,
- int);
-STATIC void xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
-#else
-
-#define xfs_icsb_balance_counter(mp, a, b) do { } while (0)
-#define xfs_icsb_balance_counter_locked(mp, a, b) do { } while (0)
-#endif
-
static DEFINE_MUTEX(xfs_uuid_table_mutex);
static int xfs_uuid_table_size;
static uuid_t *xfs_uuid_table;
@@ -347,8 +335,7 @@ reread:
goto reread;
}

- /* Initialize per-cpu counters */
- xfs_icsb_reinit_counters(mp);
+ xfs_reinit_percpu_counters(mp);

/* no need to be quiet anymore, so reset the buf ops */
bp->b_ops = &xfs_sb_buf_ops;
@@ -1087,8 +1074,6 @@ xfs_log_sbcount(xfs_mount_t *mp)
if (!xfs_fs_writable(mp, SB_FREEZE_COMPLETE))
return 0;

- xfs_icsb_sync_counters(mp, 0);
-
/*
* we don't need to do this if we are updating the superblock
* counters on every modification.
@@ -1467,502 +1452,3 @@ xfs_dev_is_read_only(
}
return 0;
}
-
-#ifdef HAVE_PERCPU_SB
-/*
- * Per-cpu incore superblock counters
- *
- * Simple concept, difficult implementation
- *
- * Basically, replace the incore superblock counters with a distributed per cpu
- * counter for contended fields (e.g. free block count).
- *
- * Difficulties arise in that the incore sb is used for ENOSPC checking, and
- * hence needs to be accurately read when we are running low on space. Hence
- * there is a method to enable and disable the per-cpu counters based on how
- * much "stuff" is available in them.
- *
- * Basically, a counter is enabled if there is enough free resource to justify
- * running a per-cpu fast-path. If the per-cpu counter runs out (i.e. a local
- * ENOSPC), then we disable the counters to synchronise all callers and
- * re-distribute the available resources.
- *
- * If, once we redistributed the available resources, we still get a failure,
- * we disable the per-cpu counter and go through the slow path.
- *
- * The slow path is the current xfs_mod_incore_sb() function. This means that
- * when we disable a per-cpu counter, we need to drain its resources back to
- * the global superblock. We do this after disabling the counter to prevent
- * more threads from queueing up on the counter.
- *
- * Essentially, this means that we still need a lock in the fast path to enable
- * synchronisation between the global counters and the per-cpu counters. This
- * is not a problem because the lock will be local to a CPU almost all the time
- * and have little contention except when we get to ENOSPC conditions.
- *
- * Basically, this lock becomes a barrier that enables us to lock out the fast
- * path while we do things like enabling and disabling counters and
- * synchronising the counters.
- *
- * Locking rules:
- *
- * 1. m_sb_lock before picking up per-cpu locks
- * 2. per-cpu locks always picked up via for_each_online_cpu() order
- * 3. accurate counter sync requires m_sb_lock + per cpu locks
- * 4. modifying per-cpu counters requires holding per-cpu lock
- * 5. modifying global counters requires holding m_sb_lock
- * 6. enabling or disabling a counter requires holding the m_sb_lock
- * and _none_ of the per-cpu locks.
- *
- * Disabled counters are only ever re-enabled by a balance operation
- * that results in more free resources per CPU than a given threshold.
- * To ensure counters don't remain disabled, they are rebalanced when
- * the global resource goes above a higher threshold (i.e. some hysteresis
- * is present to prevent thrashing).
- */
-
-#ifdef CONFIG_HOTPLUG_CPU
-/*
- * hot-plug CPU notifier support.
- *
- * We need a notifier per filesystem as we need to be able to identify
- * the filesystem to balance the counters out. This is achieved by
- * having a notifier block embedded in the xfs_mount_t and doing pointer
- * magic to get the mount pointer from the notifier block address.
- */
-STATIC int
-xfs_icsb_cpu_notify(
- struct notifier_block *nfb,
- unsigned long action,
- void *hcpu)
-{
- xfs_icsb_cnts_t *cntp;
- xfs_mount_t *mp;
-
- mp = (xfs_mount_t *)container_of(nfb, xfs_mount_t, m_icsb_notifier);
- cntp = (xfs_icsb_cnts_t *)
- per_cpu_ptr(mp->m_sb_cnts, (unsigned long)hcpu);
- switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- /* Easy Case - initialize the area and locks, and
- * then rebalance when online does everything else for us. */
- memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
- break;
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- xfs_icsb_lock(mp);
- xfs_icsb_unlock(mp);
- break;
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- /* Disable all the counters, then fold the dead cpu's
- * count into the total on the global superblock and
- * re-enable the counters. */
- xfs_icsb_lock(mp);
- spin_lock(&mp->m_sb_lock);
-
- memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
-
- spin_unlock(&mp->m_sb_lock);
- xfs_icsb_unlock(mp);
- break;
- }
-
- return NOTIFY_OK;
-}
-#endif /* CONFIG_HOTPLUG_CPU */
-
-int
-xfs_icsb_init_counters(
- xfs_mount_t *mp)
-{
- xfs_icsb_cnts_t *cntp;
- int error;
- int i;
-
- error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
- if (error)
- return error;
-
- error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
- if (error)
- goto free_icount;
-
- error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
- if (error)
- goto free_ifree;
-
- mp->m_sb_cnts = alloc_percpu(xfs_icsb_cnts_t);
- if (!mp->m_sb_cnts) {
- error = -ENOMEM;
- goto free_fdblocks;
- }
-
- for_each_online_cpu(i) {
- cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
- memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
- }
-
- mutex_init(&mp->m_icsb_mutex);
-
- /*
- * start with all counters disabled so that the
- * initial balance kicks us off correctly
- */
- mp->m_icsb_counters = -1;
-
-#ifdef CONFIG_HOTPLUG_CPU
- mp->m_icsb_notifier.notifier_call = xfs_icsb_cpu_notify;
- mp->m_icsb_notifier.priority = 0;
- register_hotcpu_notifier(&mp->m_icsb_notifier);
-#endif /* CONFIG_HOTPLUG_CPU */
-
- return 0;
-
-free_fdblocks:
- percpu_counter_destroy(&mp->m_fdblocks);
-free_ifree:
- percpu_counter_destroy(&mp->m_ifree);
-free_icount:
- percpu_counter_destroy(&mp->m_icount);
- return error;
-}
-
-void
-xfs_icsb_reinit_counters(
- xfs_mount_t *mp)
-{
- percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
- percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
- percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
-
- xfs_icsb_lock(mp);
- /*
- * start with all counters disabled so that the
- * initial balance kicks us off correctly
- */
- mp->m_icsb_counters = -1;
- xfs_icsb_unlock(mp);
-}
-
-void
-xfs_icsb_destroy_counters(
- xfs_mount_t *mp)
-{
- if (mp->m_sb_cnts) {
- unregister_hotcpu_notifier(&mp->m_icsb_notifier);
- free_percpu(mp->m_sb_cnts);
- }
-
- percpu_counter_destroy(&mp->m_icount);
- percpu_counter_destroy(&mp->m_ifree);
- percpu_counter_destroy(&mp->m_fdblocks);
-
- mutex_destroy(&mp->m_icsb_mutex);
-}
-
-STATIC void
-xfs_icsb_lock_cntr(
- xfs_icsb_cnts_t *icsbp)
-{
- while (test_and_set_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags)) {
- ndelay(1000);
- }
-}
-
-STATIC void
-xfs_icsb_unlock_cntr(
- xfs_icsb_cnts_t *icsbp)
-{
- clear_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags);
-}
-
-
-STATIC void
-xfs_icsb_lock_all_counters(
- xfs_mount_t *mp)
-{
- xfs_icsb_cnts_t *cntp;
- int i;
-
- for_each_online_cpu(i) {
- cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
- xfs_icsb_lock_cntr(cntp);
- }
-}
-
-STATIC void
-xfs_icsb_unlock_all_counters(
- xfs_mount_t *mp)
-{
- xfs_icsb_cnts_t *cntp;
- int i;
-
- for_each_online_cpu(i) {
- cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
- xfs_icsb_unlock_cntr(cntp);
- }
-}
-
-STATIC void
-xfs_icsb_count(
- xfs_mount_t *mp,
- xfs_icsb_cnts_t *cnt,
- int flags)
-{
- memset(cnt, 0, sizeof(xfs_icsb_cnts_t));
-
- if (!(flags & XFS_ICSB_LAZY_COUNT))
- xfs_icsb_lock_all_counters(mp);
-
-
- if (!(flags & XFS_ICSB_LAZY_COUNT))
- xfs_icsb_unlock_all_counters(mp);
-}
-
-STATIC int
-xfs_icsb_counter_disabled(
- xfs_mount_t *mp,
- xfs_sb_field_t field)
-{
- return test_bit(field, &mp->m_icsb_counters);
-}
-
-STATIC void
-xfs_icsb_disable_counter(
- xfs_mount_t *mp,
- xfs_sb_field_t field)
-{
- xfs_icsb_cnts_t cnt;
-
- /*
- * If we are already disabled, then there is nothing to do
- * here. We check before locking all the counters to avoid
- * the expensive lock operation when being called in the
- * slow path and the counter is already disabled. This is
- * safe because the only time we set or clear this state is under
- * the m_icsb_mutex.
- */
- if (xfs_icsb_counter_disabled(mp, field))
- return;
-
- xfs_icsb_lock_all_counters(mp);
- if (!test_and_set_bit(field, &mp->m_icsb_counters)) {
- /* drain back to superblock */
-
- xfs_icsb_count(mp, &cnt, XFS_ICSB_LAZY_COUNT);
- switch(field) {
- default:
- BUG();
- }
- }
-
- xfs_icsb_unlock_all_counters(mp);
-}
-
-STATIC void
-xfs_icsb_enable_counter(
- xfs_mount_t *mp,
- xfs_sb_field_t field,
- uint64_t count,
- uint64_t resid)
-{
- int i;
-
- xfs_icsb_lock_all_counters(mp);
- for_each_online_cpu(i) {
- switch (field) {
- default:
- BUG();
- break;
- }
- resid = 0;
- }
- clear_bit(field, &mp->m_icsb_counters);
- xfs_icsb_unlock_all_counters(mp);
-}
-
-void
-xfs_icsb_sync_counters_locked(
- xfs_mount_t *mp,
- int flags)
-{
- xfs_icsb_cnts_t cnt;
-
- xfs_icsb_count(mp, &cnt, flags);
-}
-
-/*
- * Accurate update of per-cpu counters to incore superblock
- */
-void
-xfs_icsb_sync_counters(
- xfs_mount_t *mp,
- int flags)
-{
- spin_lock(&mp->m_sb_lock);
- xfs_icsb_sync_counters_locked(mp, flags);
- spin_unlock(&mp->m_sb_lock);
-}
-
-/*
- * Balance and enable/disable counters as necessary.
- *
- * Thresholds for re-enabling counters are somewhat magic. inode counts are
- * chosen to be the same number as single on disk allocation chunk per CPU, and
- * free blocks is something far enough zero that we aren't going thrash when we
- * get near ENOSPC. We also need to supply a minimum we require per cpu to
- * prevent looping endlessly when xfs_alloc_space asks for more than will
- * be distributed to a single CPU but each CPU has enough blocks to be
- * reenabled.
- *
- * Note that we can be called when counters are already disabled.
- * xfs_icsb_disable_counter() optimises the counter locking in this case to
- * prevent locking every per-cpu counter needlessly.
- */
-
-#define XFS_ICSB_INO_CNTR_REENABLE (uint64_t)64
-#define XFS_ICSB_FDBLK_CNTR_REENABLE(mp) \
- (uint64_t)(512 + XFS_ALLOC_SET_ASIDE(mp))
-STATIC void
-xfs_icsb_balance_counter_locked(
- xfs_mount_t *mp,
- xfs_sb_field_t field,
- int min_per_cpu)
-{
- uint64_t count, resid;
-
- /* disable counter and sync counter */
- xfs_icsb_disable_counter(mp, field);
-
- /* update counters - first CPU gets residual*/
- switch (field) {
- default:
- BUG();
- count = resid = 0; /* quiet, gcc */
- break;
- }
-
- xfs_icsb_enable_counter(mp, field, count, resid);
-}
-
-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);
-}
-
-int
-xfs_icsb_modify_counters(
- xfs_mount_t *mp,
- xfs_sb_field_t field,
- int64_t delta,
- int rsvd)
-{
- xfs_icsb_cnts_t *icsbp;
- int ret = 0;
-
- might_sleep();
-again:
- preempt_disable();
- icsbp = this_cpu_ptr(mp->m_sb_cnts);
-
- /*
- * if the counter is disabled, go to slow path
- */
- if (unlikely(xfs_icsb_counter_disabled(mp, field)))
- goto slow_path;
- xfs_icsb_lock_cntr(icsbp);
- if (unlikely(xfs_icsb_counter_disabled(mp, field))) {
- xfs_icsb_unlock_cntr(icsbp);
- goto slow_path;
- }
-
- switch (field) {
- default:
- BUG();
- goto balance_counter; /* be still, gcc */
- }
- xfs_icsb_unlock_cntr(icsbp);
- preempt_enable();
- return 0;
-
-slow_path:
- preempt_enable();
-
- /*
- * serialise with a mutex so we don't burn lots of cpu on
- * the superblock lock. We still need to hold the superblock
- * lock, however, when we modify the global structures.
- */
- xfs_icsb_lock(mp);
-
- /*
- * Now running atomically.
- *
- * If the counter is enabled, someone has beaten us to rebalancing.
- * Drop the lock and try again in the fast path....
- */
- if (!(xfs_icsb_counter_disabled(mp, field))) {
- xfs_icsb_unlock(mp);
- goto again;
- }
-
- /*
- * The counter is currently disabled. Because we are
- * running atomically here, we know a rebalance cannot
- * be in progress. Hence we can go straight to operating
- * on the global superblock. We do not call xfs_mod_incore_sb()
- * here even though we need to get the m_sb_lock. Doing so
- * will cause us to re-enter this function and deadlock.
- * Hence we get the m_sb_lock ourselves and then call
- * xfs_mod_incore_sb_unlocked() as the unlocked path operates
- * directly on the global counters.
- */
- spin_lock(&mp->m_sb_lock);
- ret = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
- spin_unlock(&mp->m_sb_lock);
-
- /*
- * Now that we've modified the global superblock, we
- * may be able to re-enable the distributed counters
- * (e.g. lots of space just got freed). After that
- * we are done.
- */
- if (ret != -ENOSPC)
- xfs_icsb_balance_counter(mp, field, 0);
- xfs_icsb_unlock(mp);
- return ret;
-
-balance_counter:
- xfs_icsb_unlock_cntr(icsbp);
- preempt_enable();
-
- /*
- * We may have multiple threads here if multiple per-cpu
- * counters run dry at the same time. This will mean we can
- * do more balances than strictly necessary but it is not
- * the common slowpath case.
- */
- xfs_icsb_lock(mp);
-
- /*
- * running atomically.
- *
- * This will leave the counter in the correct state for future
- * accesses. After the rebalance, we simply try again and our retry
- * will either succeed through the fast path or slow path without
- * another balance operation being required.
- */
- xfs_icsb_balance_counter(mp, field, delta);
- xfs_icsb_unlock(mp);
- goto again;
-}
-
-#endif
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 76f5d25..ff1d1d5 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -18,8 +18,6 @@
#ifndef __XFS_MOUNT_H__
#define __XFS_MOUNT_H__

-#ifdef __KERNEL__
-
struct xlog;
struct xfs_inode;
struct xfs_mru_cache;
@@ -29,43 +27,6 @@ struct xfs_quotainfo;
struct xfs_dir_ops;
struct xfs_da_geometry;

-#ifdef HAVE_PERCPU_SB
-
-/*
- * Valid per-cpu incore superblock counters. Note that if you add new counters,
- * you may need to define new counter disabled bit field descriptors as there
- * are more possible fields in the superblock that can fit in a bitfield on a
- * 32 bit platform. The XFS_SBS_* values for the current current counters just
- * fit.
- */
-typedef struct xfs_icsb_cnts {
- uint64_t icsb_fdblocks;
- uint64_t icsb_ifree;
- unsigned long icsb_flags;
-} xfs_icsb_cnts_t;
-
-#define XFS_ICSB_FLAG_LOCK (1 << 0) /* counter lock bit */
-
-#define XFS_ICSB_LAZY_COUNT (1 << 1) /* accuracy not needed */
-
-extern int xfs_icsb_init_counters(struct xfs_mount *);
-extern void xfs_icsb_reinit_counters(struct xfs_mount *);
-extern void xfs_icsb_destroy_counters(struct xfs_mount *);
-extern void xfs_icsb_sync_counters(struct xfs_mount *, int);
-extern void xfs_icsb_sync_counters_locked(struct xfs_mount *, int);
-extern int xfs_icsb_modify_counters(struct xfs_mount *, xfs_sb_field_t,
- int64_t, int);
-
-#else
-#define xfs_icsb_init_counters(mp) (0)
-#define xfs_icsb_destroy_counters(mp) do { } while (0)
-#define xfs_icsb_reinit_counters(mp) do { } while (0)
-#define xfs_icsb_sync_counters(mp, flags) do { } while (0)
-#define xfs_icsb_sync_counters_locked(mp, flags) do { } while (0)
-#define xfs_icsb_modify_counters(mp, field, delta, rsvd) \
- xfs_mod_incore_sb(mp, field, delta, rsvd)
-#endif
-
/* dynamic preallocation free space thresholds, 5% down to 1% */
enum {
XFS_LOWSP_1_PCNT = 0,
@@ -156,12 +117,6 @@ typedef struct xfs_mount {
const struct xfs_dir_ops *m_nondir_inode_ops; /* !dir inode ops */
uint m_chsize; /* size of next field */
atomic_t m_active_trans; /* number trans frozen */
-#ifdef HAVE_PERCPU_SB
- xfs_icsb_cnts_t __percpu *m_sb_cnts; /* per-cpu superblock counters */
- unsigned long m_icsb_counters; /* disabled per-cpu counters */
- struct notifier_block m_icsb_notifier; /* hotplug cpu notifier */
- struct mutex m_icsb_mutex; /* balancer sync lock */
-#endif
struct xfs_mru_cache *m_filestream; /* per-mount filestream data */
struct delayed_work m_reclaim_work; /* background inode reclaim */
struct delayed_work m_eofblocks_work; /* background eof blocks
@@ -294,26 +249,6 @@ xfs_daddr_to_agbno(struct xfs_mount *mp, xfs_daddr_t d)
}

/*
- * Per-cpu superblock locking functions
- */
-#ifdef HAVE_PERCPU_SB
-static inline void
-xfs_icsb_lock(xfs_mount_t *mp)
-{
- mutex_lock(&mp->m_icsb_mutex);
-}
-
-static inline void
-xfs_icsb_unlock(xfs_mount_t *mp)
-{
- mutex_unlock(&mp->m_icsb_mutex);
-}
-#else
-#define xfs_icsb_lock(mp)
-#define xfs_icsb_unlock(mp)
-#endif
-
-/*
* This structure is for use by the xfs_mod_incore_sb_batch() routine.
* xfs_growfs can specify a few fields which are more than int limit
*/
@@ -396,6 +331,4 @@ extern int xfs_dev_is_read_only(struct xfs_mount *, char *);

extern void xfs_set_low_space_thresholds(struct xfs_mount *);

-#endif /* __KERNEL__ */
-
#endif /* __XFS_MOUNT_H__ */
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 4c6af31..af6d268 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1035,23 +1035,6 @@ xfs_free_fsname(
kfree(mp->m_logname);
}

-STATIC void
-xfs_fs_put_super(
- struct super_block *sb)
-{
- struct xfs_mount *mp = XFS_M(sb);
-
- xfs_filestream_unmount(mp);
- xfs_unmountfs(mp);
-
- xfs_freesb(mp);
- xfs_icsb_destroy_counters(mp);
- xfs_destroy_mount_workqueues(mp);
- xfs_close_devices(mp);
- xfs_free_fsname(mp);
- kfree(mp);
-}
-
STATIC int
xfs_fs_sync_fs(
struct super_block *sb,
@@ -1100,7 +1083,6 @@ xfs_fs_statfs(
statp->f_fsid.val[0] = (u32)id;
statp->f_fsid.val[1] = (u32)(id >> 32);

- xfs_icsb_sync_counters(mp, XFS_ICSB_LAZY_COUNT);
icount = percpu_counter_sum(&mp->m_icount);
ifree = percpu_counter_sum(&mp->m_ifree);
fdblocks = percpu_counter_sum(&mp->m_fdblocks);
@@ -1405,6 +1387,51 @@ xfs_finish_flags(
return 0;
}

+static int
+xfs_init_percpu_counters(
+ struct xfs_mount *mp)
+{
+ int error;
+
+ error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
+ if (error)
+ return ENOMEM;
+
+ error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
+ if (error)
+ goto free_icount;
+
+ error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
+ if (error)
+ goto free_ifree;
+
+ return 0;
+
+free_ifree:
+ percpu_counter_destroy(&mp->m_ifree);
+free_icount:
+ percpu_counter_destroy(&mp->m_icount);
+ return -ENOMEM;
+}
+
+void
+xfs_reinit_percpu_counters(
+ struct xfs_mount *mp)
+{
+ percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
+ percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
+ percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
+}
+
+static void
+xfs_destroy_percpu_counters(
+ struct xfs_mount *mp)
+{
+ percpu_counter_destroy(&mp->m_icount);
+ percpu_counter_destroy(&mp->m_ifree);
+ percpu_counter_destroy(&mp->m_fdblocks);
+}
+
STATIC int
xfs_fs_fill_super(
struct super_block *sb,
@@ -1453,7 +1480,7 @@ xfs_fs_fill_super(
if (error)
goto out_close_devices;

- error = xfs_icsb_init_counters(mp);
+ error = xfs_init_percpu_counters(mp);
if (error)
goto out_destroy_workqueues;

@@ -1511,7 +1538,7 @@ xfs_fs_fill_super(
out_free_sb:
xfs_freesb(mp);
out_destroy_counters:
- xfs_icsb_destroy_counters(mp);
+ xfs_destroy_percpu_counters(mp);
out_destroy_workqueues:
xfs_destroy_mount_workqueues(mp);
out_close_devices:
@@ -1528,6 +1555,23 @@ out_destroy_workqueues:
goto out_free_sb;
}

+STATIC void
+xfs_fs_put_super(
+ struct super_block *sb)
+{
+ struct xfs_mount *mp = XFS_M(sb);
+
+ xfs_filestream_unmount(mp);
+ xfs_unmountfs(mp);
+
+ xfs_freesb(mp);
+ xfs_destroy_percpu_counters(mp);
+ xfs_destroy_mount_workqueues(mp);
+ xfs_close_devices(mp);
+ xfs_free_fsname(mp);
+ kfree(mp);
+}
+
STATIC struct dentry *
xfs_fs_mount(
struct file_system_type *fs_type,
diff --git a/fs/xfs/xfs_super.h b/fs/xfs/xfs_super.h
index 2b830c2..499058f 100644
--- a/fs/xfs/xfs_super.h
+++ b/fs/xfs/xfs_super.h
@@ -72,6 +72,8 @@ extern const struct export_operations xfs_export_operations;
extern const struct xattr_handler *xfs_xattr_handlers[];
extern const struct quotactl_ops xfs_quotactl_operations;

+extern void xfs_reinit_percpu_counters(struct xfs_mount *mp);
+
#define XFS_M(sb) ((struct xfs_mount *)((sb)->s_fs_info))

#endif /* __XFS_SUPER_H__ */
--
2.0.0