bcache: Zero less memory

Another minor performance optimization

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

diff --git a/drivers/md/bcache/closure.h b/drivers/md/bcache/closure.h
index 9762f1b..d29b773 100644 (file)
--- 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 59b3d6d..cce02f1 100644 (file)
--- 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 2cd65bf..39f21db 100644 (file)
--- 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);
 };