bcache: Kill sequential_merge option

It never really made sense to expose this, so just kill it.

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

4 files changed, 18 insertions, 31 deletions

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index d6970a651e42..322735547eab 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -364,7 +364,6 @@ struct cached_dev {
         unsigned                sequential_cutoff;
         unsigned                readahead;
 
-        unsigned                sequential_merge:1;
         unsigned                verify:1;
 
         unsigned                partial_stripes_expensive:1;
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 932300f18973..f645da61189a 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -510,6 +510,7 @@ static bool check_should_bypass(struct cached_dev *dc, struct bio *bio)
         unsigned mode = cache_mode(dc, bio);
         unsigned sectors, congested = bch_get_congested(c);
         struct task_struct *task = current;
+        struct io *i;
 
         if (atomic_read(&dc->disk.detaching) ||
             c->gc_stats.in_use > CUTOFF_CACHE_ADD ||
@@ -536,38 +537,30 @@ static bool check_should_bypass(struct cached_dev *dc, struct bio *bio)
             (bio->bi_rw & REQ_SYNC))
                 goto rescale;
 
-        if (dc->sequential_merge) {
-                struct io *i;
+        spin_lock(&dc->io_lock);
 
-                spin_lock(&dc->io_lock);
+        hlist_for_each_entry(i, iohash(dc, bio->bi_sector), hash)
+                if (i->last == bio->bi_sector &&
+                    time_before(jiffies, i->jiffies))
+                        goto found;
 
-                hlist_for_each_entry(i, iohash(dc, bio->bi_sector), hash)
-                        if (i->last == bio->bi_sector &&
-                            time_before(jiffies, i->jiffies))
-                                goto found;
+        i = list_first_entry(&dc->io_lru, struct io, lru);
 
-                i = list_first_entry(&dc->io_lru, struct io, lru);
-
-                add_sequential(task);
-                i->sequential = 0;
+        add_sequential(task);
+        i->sequential = 0;
 found:
-                if (i->sequential + bio->bi_size > i->sequential)
-                        i->sequential   += bio->bi_size;
-
-                i->last                  = bio_end_sector(bio);
-                i->jiffies               = jiffies + msecs_to_jiffies(5000);
-                task->sequential_io      = i->sequential;
+        if (i->sequential + bio->bi_size > i->sequential)
+                i->sequential   += bio->bi_size;
 
-                hlist_del(&i->hash);
-                hlist_add_head(&i->hash, iohash(dc, i->last));
-                list_move_tail(&i->lru, &dc->io_lru);
+        i->last                  = bio_end_sector(bio);
+        i->jiffies               = jiffies + msecs_to_jiffies(5000);
+        task->sequential_io      = i->sequential;
 
-                spin_unlock(&dc->io_lock);
-        } else {
-                task->sequential_io = bio->bi_size;
+        hlist_del(&i->hash);
+        hlist_add_head(&i->hash, iohash(dc, i->last));
+        list_move_tail(&i->lru, &dc->io_lru);
 
-                add_sequential(task);
-        }
+        spin_unlock(&dc->io_lock);
 
         sectors = max(task->sequential_io,
                       task->sequential_io_avg) >> 9;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index e21200e98da6..041dd9d1d882 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1079,7 +1079,6 @@ static int cached_dev_init(struct cached_dev *dc, unsigned block_size)
         spin_lock_init(&dc->io_lock);
         bch_cache_accounting_init(&dc->accounting, &dc->disk.cl);
 
-        dc->sequential_merge            = true;
         dc->sequential_cutoff           = 4 << 20;
 
         for (io = dc->io; io < dc->io + RECENT_IO; io++) {
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index c5f73e34d016..4b672449ffaf 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -72,7 +72,6 @@ rw_attribute(congested_read_threshold_us);
 rw_attribute(congested_write_threshold_us);
 
 rw_attribute(sequential_cutoff);
-rw_attribute(sequential_merge);
 rw_attribute(data_csum);
 rw_attribute(cache_mode);
 rw_attribute(writeback_metadata);
@@ -161,7 +160,6 @@ SHOW(__bch_cached_dev)
         sysfs_hprint(stripe_size,       dc->disk.stripe_size << 9);
         var_printf(partial_stripes_expensive,   "%u");
 
-        var_printf(sequential_merge,    "%i");
         var_hprint(sequential_cutoff);
         var_hprint(readahead);
 
@@ -207,7 +205,6 @@ STORE(__cached_dev)
                             dc->writeback_rate_p_term_inverse, 1, INT_MAX);
         d_strtoul(writeback_rate_d_smooth);
 
-        d_strtoul(sequential_merge);
         d_strtoi_h(sequential_cutoff);
         d_strtoi_h(readahead);
 
@@ -319,7 +316,6 @@ static struct attribute *bch_cached_dev_files[] = {
         &sysfs_stripe_size,
         &sysfs_partial_stripes_expensive,
         &sysfs_sequential_cutoff,
-        &sysfs_sequential_merge,
         &sysfs_clear_stats,
         &sysfs_running,
         &sysfs_state,