dm cache: speed up writing of the hint array
It's far quicker to always delete the hint array and recreate with
dm_array_new() because we avoid the copying caused by mutation.
Also simplifies the policy interface, replacing the walk_hints() with
the simpler get_hint().
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
diff --git a/drivers/md/dm-cache-policy-internal.h b/drivers/md/dm-cache-policy-internal.h
index 2816018..808ee0e 100644
--- a/drivers/md/dm-cache-policy-internal.h
+++ b/drivers/md/dm-cache-policy-internal.h
@@ -48,10 +48,10 @@
return p->load_mapping(p, oblock, cblock, hint, hint_valid);
}
-static inline int policy_walk_mappings(struct dm_cache_policy *p,
- policy_walk_fn fn, void *context)
+static inline uint32_t policy_get_hint(struct dm_cache_policy *p,
+ dm_cblock_t cblock)
{
- return p->walk_mappings ? p->walk_mappings(p, fn, context) : 0;
+ return p->get_hint ? p->get_hint(p, cblock) : 0;
}
static inline int policy_writeback_work(struct dm_cache_policy *p,