[PATCH 041/102] xfs: add the xlog_grant_head structure

Dave Chinner
2012-08-23T05:03:37Z

From: Christoph Hellwig <hch@infradead.org>

Upstream commit: 28496968a6ac37c8b8c44b5156e633c581bb8378

Add a new data structure to allow sharing code between the log grant and
regrant code.

Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
---
fs/xfs/linux-2.6/xfs_trace.h | 8 +--
fs/xfs/xfs_log.c | 112 +++++++++++++++++++++---------------------
fs/xfs/xfs_log_priv.h | 23 ++++-----
fs/xfs/xfs_log_recover.c | 4 +-
4 files changed, 74 insertions(+), 73 deletions(-)

diff --git a/fs/xfs/linux-2.6/xfs_trace.h b/fs/xfs/linux-2.6/xfs_trace.h
index 70c7739..cc7311c 100644
--- a/fs/xfs/linux-2.6/xfs_trace.h
+++ b/fs/xfs/linux-2.6/xfs_trace.h
@@ -786,12 +786,12 @@ DECLARE_EVENT_CLASS(xfs_loggrant_class,
__entry->curr_res = tic->t_curr_res;
__entry->unit_res = tic->t_unit_res;
__entry->flags = tic->t_flags;
- __entry->reserveq = list_empty(&log->l_reserveq);
- __entry->writeq = list_empty(&log->l_writeq);
- xlog_crack_grant_head(&log->l_grant_reserve_head,
+ __entry->reserveq = list_empty(&log->l_reserve_head.waiters);
+ __entry->writeq = list_empty(&log->l_write_head.waiters);
+ xlog_crack_grant_head(&log->l_reserve_head.grant,
&__entry->grant_reserve_cycle,
&__entry->grant_reserve_bytes);
- xlog_crack_grant_head(&log->l_grant_write_head,
+ xlog_crack_grant_head(&log->l_write_head.grant,
&__entry->grant_write_cycle,
&__entry->grant_write_bytes);
__entry->curr_cycle = log->l_curr_cycle;
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index fc2b84b..5c5aa54 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -158,7 +158,7 @@ xlog_reserveq_wake(
struct xlog_ticket *tic;
int need_bytes;

- list_for_each_entry(tic, &log->l_reserveq, t_queue) {
+ list_for_each_entry(tic, &log->l_reserve_head.waiters, t_queue) {
if (tic->t_flags & XLOG_TIC_PERM_RESERV)
need_bytes = tic->t_unit_res * tic->t_cnt;
else
@@ -183,7 +183,7 @@ xlog_writeq_wake(
struct xlog_ticket *tic;
int need_bytes;

- list_for_each_entry(tic, &log->l_writeq, t_queue) {
+ list_for_each_entry(tic, &log->l_write_head.waiters, t_queue) {
ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);

need_bytes = tic->t_unit_res;
@@ -205,7 +205,7 @@ xlog_reserveq_wait(
struct xlog_ticket *tic,
int need_bytes)
{
- list_add_tail(&tic->t_queue, &log->l_reserveq);
+ list_add_tail(&tic->t_queue, &log->l_reserve_head.waiters);

do {
if (XLOG_FORCED_SHUTDOWN(log))
@@ -213,7 +213,7 @@ xlog_reserveq_wait(
xlog_grant_push_ail(log, need_bytes);

__set_current_state(TASK_UNINTERRUPTIBLE);
- spin_unlock(&log->l_grant_reserve_lock);
+ spin_unlock(&log->l_reserve_head.lock);

XFS_STATS_INC(xs_sleep_logspace);

@@ -221,10 +221,10 @@ xlog_reserveq_wait(
schedule();
trace_xfs_log_grant_wake(log, tic);

- spin_lock(&log->l_grant_reserve_lock);
+ spin_lock(&log->l_reserve_head.lock);
if (XLOG_FORCED_SHUTDOWN(log))
goto shutdown;
- } while (xlog_space_left(log, &log->l_grant_reserve_head) < need_bytes);
+ } while (xlog_space_left(log, &log->l_reserve_head.grant) < need_bytes);

list_del_init(&tic->t_queue);
return 0;
@@ -239,7 +239,7 @@ xlog_writeq_wait(
struct xlog_ticket *tic,
int need_bytes)
{
- list_add_tail(&tic->t_queue, &log->l_writeq);
+ list_add_tail(&tic->t_queue, &log->l_write_head.waiters);

do {
if (XLOG_FORCED_SHUTDOWN(log))
@@ -247,7 +247,7 @@ xlog_writeq_wait(
xlog_grant_push_ail(log, need_bytes);

__set_current_state(TASK_UNINTERRUPTIBLE);
- spin_unlock(&log->l_grant_write_lock);
+ spin_unlock(&log->l_write_head.lock);

XFS_STATS_INC(xs_sleep_logspace);

@@ -255,10 +255,10 @@ xlog_writeq_wait(
schedule();
trace_xfs_log_regrant_write_wake(log, tic);

- spin_lock(&log->l_grant_write_lock);
+ spin_lock(&log->l_write_head.lock);
if (XLOG_FORCED_SHUTDOWN(log))
goto shutdown;
- } while (xlog_space_left(log, &log->l_grant_write_head) < need_bytes);
+ } while (xlog_space_left(log, &log->l_write_head.grant) < need_bytes);

list_del_init(&tic->t_queue);
return 0;
@@ -811,22 +811,22 @@ xfs_log_space_wake(
if (XLOG_FORCED_SHUTDOWN(log))
return;

- if (!list_empty_careful(&log->l_writeq)) {
+ if (!list_empty_careful(&log->l_write_head.waiters)) {
ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));

- spin_lock(&log->l_grant_write_lock);
- free_bytes = xlog_space_left(log, &log->l_grant_write_head);
+ spin_lock(&log->l_write_head.lock);
+ free_bytes = xlog_space_left(log, &log->l_write_head.grant);
xlog_writeq_wake(log, &free_bytes);
- spin_unlock(&log->l_grant_write_lock);
+ spin_unlock(&log->l_write_head.lock);
}

- if (!list_empty_careful(&log->l_reserveq)) {
+ if (!list_empty_careful(&log->l_reserve_head.waiters)) {
ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));

- spin_lock(&log->l_grant_reserve_lock);
- free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
+ spin_lock(&log->l_reserve_head.lock);
+ free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
xlog_reserveq_wake(log, &free_bytes);
- spin_unlock(&log->l_grant_reserve_lock);
+ spin_unlock(&log->l_reserve_head.lock);
}
}

@@ -1108,12 +1108,12 @@ xlog_alloc_log(xfs_mount_t *mp,
xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0);
xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0);
log->l_curr_cycle = 1; /* 0 is bad since this is initial value */
- xlog_assign_grant_head(&log->l_grant_reserve_head, 1, 0);
- xlog_assign_grant_head(&log->l_grant_write_head, 1, 0);
- INIT_LIST_HEAD(&log->l_reserveq);
- INIT_LIST_HEAD(&log->l_writeq);
- spin_lock_init(&log->l_grant_reserve_lock);
- spin_lock_init(&log->l_grant_write_lock);
+ xlog_assign_grant_head(&log->l_reserve_head.grant, 1, 0);
+ xlog_assign_grant_head(&log->l_write_head.grant, 1, 0);
+ INIT_LIST_HEAD(&log->l_reserve_head.waiters);
+ INIT_LIST_HEAD(&log->l_write_head.waiters);
+ spin_lock_init(&log->l_reserve_head.lock);
+ spin_lock_init(&log->l_write_head.lock);

error = EFSCORRUPTED;
if (xfs_sb_version_hassector(&mp->m_sb)) {
@@ -1293,7 +1293,7 @@ xlog_grant_push_ail(

ASSERT(BTOBB(need_bytes) < log->l_logBBsize);

- free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
+ free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
free_blocks = BTOBBT(free_bytes);

/*
@@ -1427,8 +1427,8 @@ xlog_sync(xlog_t *log,
roundoff < BBTOB(1)));

/* move grant heads by roundoff in sync */
- xlog_grant_add_space(log, &log->l_grant_reserve_head, roundoff);
- xlog_grant_add_space(log, &log->l_grant_write_head, roundoff);
+ xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff);
+ xlog_grant_add_space(log, &log->l_write_head.grant, roundoff);

/* put cycle number in every block */
xlog_pack_data(log, iclog, roundoff);
@@ -2595,8 +2595,8 @@ restart:
* path. Hence any lock will be globally hot if we take it unconditionally on
* every pass.
*
- * As tickets are only ever moved on and off the reserveq under the
- * l_grant_reserve_lock, we only need to take that lock if we are going to add
+ * As tickets are only ever moved on and off the l_reserve.waiters under the
+ * l_reserve.lock, we only need to take that lock if we are going to add
* the ticket to the queue and sleep. We can avoid taking the lock if the ticket
* was never added to the reserveq because the t_queue list head will be empty
* and we hold the only reference to it so it can safely be checked unlocked.
@@ -2622,23 +2622,23 @@ xlog_grant_log_space(
need_bytes = tic->t_unit_res;
if (tic->t_flags & XFS_LOG_PERM_RESERV)
need_bytes *= tic->t_ocnt;
- free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
- if (!list_empty_careful(&log->l_reserveq)) {
- spin_lock(&log->l_grant_reserve_lock);
+ free_bytes = xlog_space_left(log, &log->l_reserve_head.grant);
+ if (!list_empty_careful(&log->l_reserve_head.waiters)) {
+ spin_lock(&log->l_reserve_head.lock);
if (!xlog_reserveq_wake(log, &free_bytes) ||
free_bytes < need_bytes)
error = xlog_reserveq_wait(log, tic, need_bytes);
- spin_unlock(&log->l_grant_reserve_lock);
+ spin_unlock(&log->l_reserve_head.lock);
} else if (free_bytes < need_bytes) {
- spin_lock(&log->l_grant_reserve_lock);
+ spin_lock(&log->l_reserve_head.lock);
error = xlog_reserveq_wait(log, tic, need_bytes);
- spin_unlock(&log->l_grant_reserve_lock);
+ spin_unlock(&log->l_reserve_head.lock);
}
if (error)
return error;

- xlog_grant_add_space(log, &log->l_grant_reserve_head, need_bytes);
- xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes);
+ xlog_grant_add_space(log, &log->l_reserve_head.grant, need_bytes);
+ xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
trace_xfs_log_grant_exit(log, tic);
xlog_verify_grant_tail(log);
return 0;
@@ -2675,23 +2675,23 @@ xlog_regrant_write_log_space(
* otherwise try to get some space for this transaction.
*/
need_bytes = tic->t_unit_res;
- free_bytes = xlog_space_left(log, &log->l_grant_write_head);
- if (!list_empty_careful(&log->l_writeq)) {
- spin_lock(&log->l_grant_write_lock);
+ free_bytes = xlog_space_left(log, &log->l_write_head.grant);
+ if (!list_empty_careful(&log->l_write_head.waiters)) {
+ spin_lock(&log->l_write_head.lock);
if (!xlog_writeq_wake(log, &free_bytes) ||
free_bytes < need_bytes)
error = xlog_writeq_wait(log, tic, need_bytes);
- spin_unlock(&log->l_grant_write_lock);
+ spin_unlock(&log->l_write_head.lock);
} else if (free_bytes < need_bytes) {
- spin_lock(&log->l_grant_write_lock);
+ spin_lock(&log->l_write_head.lock);
error = xlog_writeq_wait(log, tic, need_bytes);
- spin_unlock(&log->l_grant_write_lock);
+ spin_unlock(&log->l_write_head.lock);
}

if (error)
return error;

- xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes);
+ xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes);
trace_xfs_log_regrant_write_exit(log, tic);
xlog_verify_grant_tail(log);
return 0;
@@ -2713,9 +2713,9 @@ xlog_regrant_reserve_log_space(xlog_t *log,
if (ticket->t_cnt > 0)
ticket->t_cnt--;

- xlog_grant_sub_space(log, &log->l_grant_reserve_head,
+ xlog_grant_sub_space(log, &log->l_reserve_head.grant,
ticket->t_curr_res);
- xlog_grant_sub_space(log, &log->l_grant_write_head,
+ xlog_grant_sub_space(log, &log->l_write_head.grant,
ticket->t_curr_res);
ticket->t_curr_res = ticket->t_unit_res;
xlog_tic_reset_res(ticket);
@@ -2726,7 +2726,7 @@ xlog_regrant_reserve_log_space(xlog_t *log,
if (ticket->t_cnt > 0)
return;

- xlog_grant_add_space(log, &log->l_grant_reserve_head,
+ xlog_grant_add_space(log, &log->l_reserve_head.grant,
ticket->t_unit_res);

trace_xfs_log_regrant_reserve_exit(log, ticket);
@@ -2772,8 +2772,8 @@ xlog_ungrant_log_space(xlog_t *log,
bytes += ticket->t_unit_res*ticket->t_cnt;
}

- xlog_grant_sub_space(log, &log->l_grant_reserve_head, bytes);
- xlog_grant_sub_space(log, &log->l_grant_write_head, bytes);
+ xlog_grant_sub_space(log, &log->l_reserve_head.grant, bytes);
+ xlog_grant_sub_space(log, &log->l_write_head.grant, bytes);

trace_xfs_log_ungrant_exit(log, ticket);

@@ -3400,7 +3400,7 @@ xlog_verify_grant_tail(
int tail_cycle, tail_blocks;
int cycle, space;

- xlog_crack_grant_head(&log->l_grant_write_head, &cycle, &space);
+ xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &space);
xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks);
if (tail_cycle != cycle) {
if (cycle - 1 != tail_cycle &&
@@ -3670,15 +3670,15 @@ xfs_log_force_umount(
* we don't enqueue anything once the SHUTDOWN flag is set, and this
* action is protected by the grant locks.
*/
- spin_lock(&log->l_grant_reserve_lock);
- list_for_each_entry(tic, &log->l_reserveq, t_queue)
+ spin_lock(&log->l_reserve_head.lock);
+ list_for_each_entry(tic, &log->l_reserve_head.waiters, t_queue)
wake_up_process(tic->t_task);
- spin_unlock(&log->l_grant_reserve_lock);
+ spin_unlock(&log->l_reserve_head.lock);

- spin_lock(&log->l_grant_write_lock);
- list_for_each_entry(tic, &log->l_writeq, t_queue)
+ spin_lock(&log->l_write_head.lock);
+ list_for_each_entry(tic, &log->l_write_head.waiters, t_queue)
wake_up_process(tic->t_task);
- spin_unlock(&log->l_grant_write_lock);
+ spin_unlock(&log->l_write_head.lock);

if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) {
ASSERT(!logerror);
diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index d8c5e47..eba4ec9 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -470,6 +470,16 @@ struct xfs_cil {
#define XLOG_CIL_HARD_SPACE_LIMIT(log) (3 * (log->l_logsize >> 4))

/*
+ * ticket grant locks, queues and accounting have their own cachlines
+ * as these are quite hot and can be operated on concurrently.
+ */
+struct xlog_grant_head {
+ spinlock_t lock ____cacheline_aligned_in_smp;
+ struct list_head waiters;
+ atomic64_t grant;
+};
+
+/*
* The reservation head lsn is not made up of a cycle number and block number.
* Instead, it uses a cycle number and byte number. Logs don't expect to
* overflow 31 bits worth of byte offset, so using a byte number will mean
@@ -520,17 +530,8 @@ typedef struct log {
/* lsn of 1st LR with unflushed * buffers */
atomic64_t l_tail_lsn ____cacheline_aligned_in_smp;

- /*
- * ticket grant locks, queues and accounting have their own cachlines
- * as these are quite hot and can be operated on concurrently.
- */
- spinlock_t l_grant_reserve_lock ____cacheline_aligned_in_smp;
- struct list_head l_reserveq;
- atomic64_t l_grant_reserve_head;
-
- spinlock_t l_grant_write_lock ____cacheline_aligned_in_smp;
- struct list_head l_writeq;
- atomic64_t l_grant_write_head;
+ struct xlog_grant_head l_reserve_head;
+ struct xlog_grant_head l_write_head;

/* The following field are used for debugging; need to hold icloglock */
#ifdef DEBUG
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index eead6dd..687bc9f 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -964,9 +964,9 @@ xlog_find_tail(
log->l_curr_cycle++;
atomic64_set(&log->l_tail_lsn, be64_to_cpu(rhead->h_tail_lsn));
atomic64_set(&log->l_last_sync_lsn, be64_to_cpu(rhead->h_lsn));
- xlog_assign_grant_head(&log->l_grant_reserve_head, log->l_curr_cycle,
+ xlog_assign_grant_head(&log->l_reserve_head.grant, log->l_curr_cycle,
BBTOB(log->l_curr_block));
- xlog_assign_grant_head(&log->l_grant_write_head, log->l_curr_cycle,
+ xlog_assign_grant_head(&log->l_write_head.grant, log->l_curr_cycle,
BBTOB(log->l_curr_block));

/*