| Message ID | 20200815041043.45116-3-colyli@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | bcache: remove multiple caches code framework | expand |
On 8/15/20 6:10 AM, Coly Li wrote: > Currently although the bcache code has a framework for multiple caches > in a cache set, but indeed the multiple caches never completed and users > use md raid1 for multiple copies of the cached data. > > This patch does the following change in struct cache_set, to explicitly > make a cache_set only have single cache, > - Change pointer array "*cache[MAX_CACHES_PER_SET]" to a single pointer > "*cache". > - Remove pointer array "*cache_by_alloc[MAX_CACHES_PER_SET]". > - Remove "caches_loaded". > > Now the code looks as exactly what it does in practic: only one cache is > used in the cache set. > > Signed-off-by: Coly Li <colyli@suse.de> > --- > drivers/md/bcache/alloc.c | 2 +- > drivers/md/bcache/bcache.h | 8 +++----- > drivers/md/bcache/super.c | 19 ++++++++----------- > 3 files changed, 12 insertions(+), 17 deletions(-) > > diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c > index 4493ff57476d..3385f6add6df 100644 > --- a/drivers/md/bcache/alloc.c > +++ b/drivers/md/bcache/alloc.c > @@ -501,7 +501,7 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, > > bkey_init(k); > > - ca = c->cache_by_alloc[0]; > + ca = c->cache; > b = bch_bucket_alloc(ca, reserve, wait); > if (b == -1) > goto err; Maybe drop variable 'ca' altogether? > diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h > index 5ff6e9573935..aa112c1adba1 100644 > --- a/drivers/md/bcache/bcache.h > +++ b/drivers/md/bcache/bcache.h > @@ -519,9 +519,7 @@ struct cache_set { > > struct cache_sb sb; > > - struct cache *cache[MAX_CACHES_PER_SET]; > - struct cache *cache_by_alloc[MAX_CACHES_PER_SET]; > - int caches_loaded; > + struct cache *cache; > > struct bcache_device **devices; > unsigned int devices_max_used; > @@ -808,7 +806,7 @@ static inline struct cache *PTR_CACHE(struct cache_set *c, > const struct bkey *k, > unsigned int ptr) > { > - return c->cache[PTR_DEV(k, ptr)]; > + return c->cache; > } > > static inline size_t PTR_BUCKET_NR(struct cache_set *c, > @@ -890,7 +888,7 @@ do { \ > /* Looping macros */ > > #define for_each_cache(ca, cs, iter) \ > - for (iter = 0; ca = cs->cache[iter], iter < (cs)->sb.nr_in_set; iter++) > + for (iter = 0; ca = cs->cache, iter < 1; iter++) > > #define for_each_bucket(b, ca) \ > for (b = (ca)->buckets + (ca)->sb.first_bucket; \ I guess 'for_each_cache' can be killed, too. > diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c > index 7057ec48f3d1..e9ccfa17beb8 100644 > --- a/drivers/md/bcache/super.c > +++ b/drivers/md/bcache/super.c > @@ -1675,7 +1675,7 @@ static void cache_set_free(struct closure *cl) > for_each_cache(ca, c, i) > if (ca) { > ca->set = NULL; > - c->cache[ca->sb.nr_this_dev] = NULL; > + c->cache = NULL; > kobject_put(&ca->kobj); > } > > @@ -2166,7 +2166,7 @@ static const char *register_cache_set(struct cache *ca) > > list_for_each_entry(c, &bch_cache_sets, list) > if (!memcmp(c->sb.set_uuid, ca->sb.set_uuid, 16)) { > - if (c->cache[ca->sb.nr_this_dev]) > + if (c->cache) > return "duplicate cache set member"; > > if (!can_attach_cache(ca, c)) > @@ -2216,14 +2216,11 @@ static const char *register_cache_set(struct cache *ca) > > kobject_get(&ca->kobj); > ca->set = c; > - ca->set->cache[ca->sb.nr_this_dev] = ca; > - c->cache_by_alloc[c->caches_loaded++] = ca; > + ca->set->cache = ca; > > - if (c->caches_loaded == c->sb.nr_in_set) { > - err = "failed to run cache set"; > - if (run_cache_set(c) < 0) > - goto err; > - } > + err = "failed to run cache set"; > + if (run_cache_set(c) < 0) > + goto err; > > return NULL; > err: > @@ -2240,8 +2237,8 @@ void bch_cache_release(struct kobject *kobj) > unsigned int i; > > if (ca->set) { > - BUG_ON(ca->set->cache[ca->sb.nr_this_dev] != ca); > - ca->set->cache[ca->sb.nr_this_dev] = NULL; > + BUG_ON(ca->set->cache != ca); > + ca->set->cache = NULL; > } > > free_pages((unsigned long) ca->disk_buckets, ilog2(meta_bucket_pages(&ca->sb))); > Cheers, Hannes
diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index 4493ff57476d..3385f6add6df 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -501,7 +501,7 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, bkey_init(k); - ca = c->cache_by_alloc[0]; + ca = c->cache; b = bch_bucket_alloc(ca, reserve, wait); if (b == -1) goto err; diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 5ff6e9573935..aa112c1adba1 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -519,9 +519,7 @@ struct cache_set { struct cache_sb sb; - struct cache *cache[MAX_CACHES_PER_SET]; - struct cache *cache_by_alloc[MAX_CACHES_PER_SET]; - int caches_loaded; + struct cache *cache; struct bcache_device **devices; unsigned int devices_max_used; @@ -808,7 +806,7 @@ static inline struct cache *PTR_CACHE(struct cache_set *c, const struct bkey *k, unsigned int ptr) { - return c->cache[PTR_DEV(k, ptr)]; + return c->cache; } static inline size_t PTR_BUCKET_NR(struct cache_set *c, @@ -890,7 +888,7 @@ do { \ /* Looping macros */ #define for_each_cache(ca, cs, iter) \ - for (iter = 0; ca = cs->cache[iter], iter < (cs)->sb.nr_in_set; iter++) + for (iter = 0; ca = cs->cache, iter < 1; iter++) #define for_each_bucket(b, ca) \ for (b = (ca)->buckets + (ca)->sb.first_bucket; \ diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 7057ec48f3d1..e9ccfa17beb8 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1675,7 +1675,7 @@ static void cache_set_free(struct closure *cl) for_each_cache(ca, c, i) if (ca) { ca->set = NULL; - c->cache[ca->sb.nr_this_dev] = NULL; + c->cache = NULL; kobject_put(&ca->kobj); } @@ -2166,7 +2166,7 @@ static const char *register_cache_set(struct cache *ca) list_for_each_entry(c, &bch_cache_sets, list) if (!memcmp(c->sb.set_uuid, ca->sb.set_uuid, 16)) { - if (c->cache[ca->sb.nr_this_dev]) + if (c->cache) return "duplicate cache set member"; if (!can_attach_cache(ca, c)) @@ -2216,14 +2216,11 @@ static const char *register_cache_set(struct cache *ca) kobject_get(&ca->kobj); ca->set = c; - ca->set->cache[ca->sb.nr_this_dev] = ca; - c->cache_by_alloc[c->caches_loaded++] = ca; + ca->set->cache = ca; - if (c->caches_loaded == c->sb.nr_in_set) { - err = "failed to run cache set"; - if (run_cache_set(c) < 0) - goto err; - } + err = "failed to run cache set"; + if (run_cache_set(c) < 0) + goto err; return NULL; err: @@ -2240,8 +2237,8 @@ void bch_cache_release(struct kobject *kobj) unsigned int i; if (ca->set) { - BUG_ON(ca->set->cache[ca->sb.nr_this_dev] != ca); - ca->set->cache[ca->sb.nr_this_dev] = NULL; + BUG_ON(ca->set->cache != ca); + ca->set->cache = NULL; } free_pages((unsigned long) ca->disk_buckets, ilog2(meta_bucket_pages(&ca->sb)));
Currently although the bcache code has a framework for multiple caches in a cache set, but indeed the multiple caches never completed and users use md raid1 for multiple copies of the cached data. This patch does the following change in struct cache_set, to explicitly make a cache_set only have single cache, - Change pointer array "*cache[MAX_CACHES_PER_SET]" to a single pointer "*cache". - Remove pointer array "*cache_by_alloc[MAX_CACHES_PER_SET]". - Remove "caches_loaded". Now the code looks as exactly what it does in practic: only one cache is used in the cache set. Signed-off-by: Coly Li <colyli@suse.de> --- drivers/md/bcache/alloc.c | 2 +- drivers/md/bcache/bcache.h | 8 +++----- drivers/md/bcache/super.c | 19 ++++++++----------- 3 files changed, 12 insertions(+), 17 deletions(-)