Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 (83ae1700) · Commits · e / devices / android_kernel_xiaomi_markw

fs/jbd2/transaction.c

+27 −19

Original line number	Diff line number	Diff line
		@@ -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);