bcache: Zero less memory

Another minor performance optimization

Signed-off-by: Kent Overstreet <kmo@daterainc.com>

3 files changed, 41 insertions, 40 deletions

diff --git a/drivers/md/bcache/closure.h b/drivers/md/bcache/closure.h
index 9762f1be3304..d29b773b863f 100644
--- a/drivers/md/bcache/closure.h
+++ b/drivers/md/bcache/closure.h
@@ -348,24 +348,13 @@ do {								\
 } while (0)
 
 /**
- * __closure_init() - Initialize a closure, skipping the memset()
- *
- * May be used instead of closure_init() when memory has already been zeroed.
- */
-#define __closure_init(cl, parent)                              \
-        closure_init_type(cl, parent, true)
-
-/**
  * closure_init() - Initialize a closure, setting the refcount to 1
  * @cl:         closure to initialize
  * @parent:     parent of the new closure. cl will take a refcount on it for its
  *              lifetime; may be NULL.
  */
 #define closure_init(cl, parent)                                \
-do {                                                            \
-        memset((cl), 0, sizeof(*(cl)));                         \
-        __closure_init(cl, parent);                             \
-} while (0)
+        closure_init_type(cl, parent, true)
 
 static inline void closure_init_stack(struct closure *cl)
 {
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 59b3d6df100b..cce02f19e6c7 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -597,14 +597,12 @@ struct search {
         /* Stack frame for bio_complete */
         struct closure          cl;
 
-        struct bcache_device    *d;
-
         struct bbio             bio;
         struct bio              *orig_bio;
         struct bio              *cache_miss;
+        struct bcache_device    *d;
 
         unsigned                insert_bio_sectors;
-
         unsigned                recoverable:1;
         unsigned                write:1;
         unsigned                read_dirty_data:1;
@@ -712,10 +710,13 @@ static void cache_lookup(struct closure *cl)
 {
         struct search *s = container_of(cl, struct search, iop.cl);
         struct bio *bio = &s->bio.bio;
+        int ret;
 
-        int ret = bch_btree_map_keys(&s->op, s->iop.c,
-                                     &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0),
-                                     cache_lookup_fn, MAP_END_KEY);
+        bch_btree_op_init(&s->op, -1);
+
+        ret = bch_btree_map_keys(&s->op, s->iop.c,
+                                 &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0),
+                                 cache_lookup_fn, MAP_END_KEY);
         if (ret == -EAGAIN)
                 continue_at(cl, cache_lookup, bcache_wq);
 
@@ -756,12 +757,12 @@ static void bio_complete(struct search *s)
         }
 }
 
-static void do_bio_hook(struct search *s)
+static void do_bio_hook(struct search *s, struct bio *orig_bio)
 {
         struct bio *bio = &s->bio.bio;
 
         bio_init(bio);
-        __bio_clone_fast(bio, s->orig_bio);
+        __bio_clone_fast(bio, orig_bio);
         bio->bi_end_io          = request_endio;
         bio->bi_private         = &s->cl;
 
@@ -780,26 +781,32 @@ static void search_free(struct closure *cl)
         mempool_free(s, s->d->c->search);
 }
 
-static struct search *search_alloc(struct bio *bio, struct bcache_device *d)
+static inline struct search *search_alloc(struct bio *bio,
+                                          struct bcache_device *d)
 {
         struct search *s;
 
         s = mempool_alloc(d->c->search, GFP_NOIO);
-        memset(s, 0, offsetof(struct search, iop.insert_keys));
 
-        __closure_init(&s->cl, NULL);
+        closure_init(&s->cl, NULL);
+        do_bio_hook(s, bio);
 
-        s->iop.inode            = d->id;
-        s->iop.c                = d->c;
-        s->d                    = d;
-        s->op.lock              = -1;
-        s->iop.write_point      = hash_long((unsigned long) current, 16);
         s->orig_bio             = bio;
-        s->write                = (bio->bi_rw & REQ_WRITE) != 0;
-        s->iop.flush_journal    = (bio->bi_rw & (REQ_FLUSH|REQ_FUA)) != 0;
+        s->cache_miss           = NULL;
+        s->d                    = d;
         s->recoverable          = 1;
+        s->write                = (bio->bi_rw & REQ_WRITE) != 0;
+        s->read_dirty_data      = 0;
         s->start_time           = jiffies;
-        do_bio_hook(s);
+
+        s->iop.c                = d->c;
+        s->iop.bio              = NULL;
+        s->iop.inode            = d->id;
+        s->iop.write_point      = hash_long((unsigned long) current, 16);
+        s->iop.write_prio       = 0;
+        s->iop.error            = 0;
+        s->iop.flags            = 0;
+        s->iop.flush_journal    = (bio->bi_rw & (REQ_FLUSH|REQ_FUA)) != 0;
 
         return s;
 }
@@ -845,7 +852,7 @@ static void cached_dev_read_error(struct closure *cl)
                 trace_bcache_read_retry(s->orig_bio);
 
                 s->iop.error = 0;
-                do_bio_hook(s);
+                do_bio_hook(s, s->orig_bio);
 
                 /* XXX: invalidate cache */
 
diff --git a/drivers/md/bcache/request.h b/drivers/md/bcache/request.h
index 2cd65bf073c2..39f21dbedc38 100644
--- a/drivers/md/bcache/request.h
+++ b/drivers/md/bcache/request.h
@@ -13,17 +13,22 @@ struct data_insert_op {
         uint16_t                write_prio;
         short                   error;
 
-        unsigned                bypass:1;
-        unsigned                writeback:1;
-        unsigned                flush_journal:1;
-        unsigned                csum:1;
+        union {
+                uint16_t        flags;
 
-        unsigned                replace:1;
-        unsigned                replace_collision:1;
+        struct {
+                unsigned        bypass:1;
+                unsigned        writeback:1;
+                unsigned        flush_journal:1;
+                unsigned        csum:1;
 
-        unsigned                insert_data_done:1;
+                unsigned        replace:1;
+                unsigned        replace_collision:1;
+
+                unsigned        insert_data_done:1;
+        };
+        };
 
-        /* Anything past this point won't get zeroed in search_alloc() */
         struct keylist          insert_keys;
         BKEY_PADDED(replace_key);
 };