gfs2: enhance log_blocks trace point to show log blocks free (97c5e43d) · Commits · 戴 / test

This patch adds some code to enhance the log_blocks trace point. It reports the number of free log blocks. This makes the trace point much more useful, especially for debugging performance problems when we can tell when the journal gets full and needs to wait for flushes, etc. Signed-off-by:

Bob Peterson <rpeterso@redhat.com> Signed-off-by:

Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/trace_gfs2.h

+4 −2

Original line number	Diff line number	Diff line
		@@ -388,15 +388,17 @@ TRACE_EVENT(gfs2_log_blocks,
		TP_STRUCT__entry(
		__field( dev_t, dev )
		__field( int, blocks )
		__field( int, blks_free )
		),

		TP_fast_assign(
		__entry->dev = sdp->sd_vfs->s_dev;
		__entry->blocks = blocks;
		__entry->blks_free = atomic_read(&sdp->sd_log_blks_free);
		),

		TP_printk("%u,%u log reserve %d", MAJOR(__entry->dev),
		MINOR(__entry->dev), __entry->blocks)
		TP_printk("%u,%u log reserve %d %d", MAJOR(__entry->dev),
		MINOR(__entry->dev), __entry->blocks, __entry->blks_free)
		);

		/* Writing back the AIL */

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