===================================================================
@@ -208,7 +208,8 @@ struct log_header {
struct log_c {
struct dm_target *ti;
- int touched;
+ int touched_dirtied;
+ int touched_cleaned;
uint32_t region_size;
unsigned int region_count;
region_t sync_count;
@@ -253,14 +254,14 @@ static inline void log_set_bit(struct lo
uint32_t *bs, unsigned bit)
{
ext2_set_bit(bit, (unsigned long *) bs);
- l->touched = 1;
+ l->touched_cleaned = 1;
}
static inline void log_clear_bit(struct log_c *l,
uint32_t *bs, unsigned bit)
{
ext2_clear_bit(bit, (unsigned long *) bs);
- l->touched = 1;
+ l->touched_dirtied = 1;
}
/*----------------------------------------------------------------
@@ -378,7 +379,8 @@ static int create_log_context(struct dm_
}
lc->ti = ti;
- lc->touched = 0;
+ lc->touched_dirtied = 0;
+ lc->touched_cleaned = 0;
lc->region_size = region_size;
lc->region_count = region_count;
lc->sync = sync;
@@ -658,14 +660,16 @@ static int disk_flush(struct dm_dirty_lo
struct log_c *lc = (struct log_c *) log->context;
/* only write if the log has changed */
- if (!lc->touched)
+ if (!lc->touched_cleaned && !lc->touched_dirtied)
return 0;
r = rw_header(lc, WRITE);
if (r)
fail_log_device(lc);
- else
- lc->touched = 0;
+ else {
+ lc->touched_dirtied = 0;
+ lc->touched_cleaned = 0;
+ }
return r;
}
Split the variable "touched" to two variables "touched_dirtied" and "touched_cleaned" that are set when some region was dirtied or cleaned. This will be used to optimize flushes. After a transition from "dirty" to "clean" state we don't have flush hardware cache on the log device. After a transition from "clean" to "dirty" the cache must be flushed. Before a transition from "clean" to "dirty" state we don't have to flush all the raid legs. Before a transition from "dirty" to "clean" we must flush all the legs to make sure that they are really in sync. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> --- drivers/md/dm-log.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel