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Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

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* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: clean up compiler warning in start_this_handle()
This commit is contained in:
Linus Torvalds 2010-08-13 17:59:26 -07:00
commit 83ae170092
1 changed files with 27 additions and 19 deletions
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46
fs/jbd2/transaction.c
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@ -81,6 +81,32 @@ jbd2_get_transaction(journal_t *journal, transaction_t *transaction)
* of that one update.
*/
/*
* Update transiaction's maximum wait time, if debugging is enabled.
*
* In order for t_max_wait to be reliable, it must be protected by a
* lock. But doing so will mean that start_this_handle() can not be
* run in parallel on SMP systems, which limits our scalability. So
* unless debugging is enabled, we no longer update t_max_wait, which
* means that maximum wait time reported by the jbd2_run_stats
* tracepoint will always be zero.
*/
static inline void update_t_max_wait(transaction_t *transaction)
{
#ifdef CONFIG_JBD2_DEBUG
unsigned long ts = jiffies;
if (jbd2_journal_enable_debug &&
time_after(transaction->t_start, ts)) {
ts = jbd2_time_diff(ts, transaction->t_start);
spin_lock(&transaction->t_handle_lock);
if (ts > transaction->t_max_wait)
transaction->t_max_wait = ts;
spin_unlock(&transaction->t_handle_lock);
}
#endif
}
/*
* start_this_handle: Given a handle, deal with any locking or stalling
* needed to make sure that there is enough journal space for the handle
@ -95,7 +121,6 @@ static int start_this_handle(journal_t *journal, handle_t *handle,
int needed;
int nblocks = handle->h_buffer_credits;
transaction_t *new_transaction = NULL;
unsigned long ts = jiffies;
if (nblocks > journal->j_max_transaction_buffers) {
printk(KERN_ERR "JBD: %s wants too many credits (%d > %d)\n",
@ -241,25 +266,8 @@ repeat:
/* OK, account for the buffers that this operation expects to
* use and add the handle to the running transaction.
*
* In order for t_max_wait to be reliable, it must be
* protected by a lock. But doing so will mean that
* start_this_handle() can not be run in parallel on SMP
* systems, which limits our scalability. So we only enable
* it when debugging is enabled. We may want to use a
* separate flag, eventually, so we can enable this
* independently of debugging.
*/
#ifdef CONFIG_JBD2_DEBUG
if (jbd2_journal_enable_debug &&
time_after(transaction->t_start, ts)) {
ts = jbd2_time_diff(ts, transaction->t_start);
spin_lock(&transaction->t_handle_lock);
if (ts > transaction->t_max_wait)
transaction->t_max_wait = ts;
spin_unlock(&transaction->t_handle_lock);
}
#endif
update_t_max_wait(transaction);
handle->h_transaction = transaction;
atomic_inc(&transaction->t_updates);
atomic_inc(&transaction->t_handle_count);