bcache: Kill bucket->gc_gen

gc_gen was a temporary used to recalculate last_gc, but since we only need
bucket->last_gc when gc isn't running (gc_mark_valid = 1), we can just update
last_gc directly.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Kent Overstreet 2014-02-27 17:51:12 -08:00
parent 2531d9ee61
commit 3a2fd9d509
4 changed files with 9 additions and 11 deletions

View File

@ -196,7 +196,6 @@ struct bucket {
uint16_t prio;
uint8_t gen;
uint8_t last_gc; /* Most out of date gen in the btree */
uint8_t gc_gen;
uint16_t gc_mark; /* Bitfield used by GC. See below for field */
};
@ -588,7 +587,7 @@ struct cache_set {
uint16_t min_prio;
/*
* max(gen - gc_gen) for all buckets. When it gets too big we have to gc
* max(gen - last_gc) for all buckets. When it gets too big we have to gc
* to keep gens from wrapping around.
*/
uint8_t need_gc;

View File

@ -1178,8 +1178,8 @@ static uint8_t __bch_btree_mark_key(struct cache_set *c, int level,
g = PTR_BUCKET(c, k, i);
if (gen_after(g->gc_gen, PTR_GEN(k, i)))
g->gc_gen = PTR_GEN(k, i);
if (gen_after(g->last_gc, PTR_GEN(k, i)))
g->last_gc = PTR_GEN(k, i);
if (ptr_stale(c, k, i)) {
stale = max(stale, ptr_stale(c, k, i));
@ -1631,7 +1631,7 @@ static void btree_gc_start(struct cache_set *c)
for_each_cache(ca, c, i)
for_each_bucket(b, ca) {
b->gc_gen = b->gen;
b->last_gc = b->gen;
if (!atomic_read(&b->pin)) {
SET_GC_MARK(b, 0);
SET_GC_SECTORS_USED(b, 0);
@ -1693,7 +1693,6 @@ static size_t bch_btree_gc_finish(struct cache_set *c)
SET_GC_MARK(ca->buckets + *i, GC_MARK_METADATA);
for_each_bucket(b, ca) {
b->last_gc = b->gc_gen;
c->need_gc = max(c->need_gc, bucket_gc_gen(b));
if (atomic_read(&b->pin))

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@ -194,9 +194,9 @@ static bool btree_ptr_bad_expensive(struct btree *b, const struct bkey *k)
mutex_unlock(&b->c->bucket_lock);
bch_extent_to_text(buf, sizeof(buf), k);
btree_bug(b,
"inconsistent btree pointer %s: bucket %zi pin %i prio %i gen %i last_gc %i mark %llu gc_gen %i",
"inconsistent btree pointer %s: bucket %zi pin %i prio %i gen %i last_gc %i mark %llu",
buf, PTR_BUCKET_NR(b->c, k, i), atomic_read(&g->pin),
g->prio, g->gen, g->last_gc, GC_MARK(g), g->gc_gen);
g->prio, g->gen, g->last_gc, GC_MARK(g));
return true;
}
@ -515,9 +515,9 @@ static bool bch_extent_bad_expensive(struct btree *b, const struct bkey *k,
mutex_unlock(&b->c->bucket_lock);
bch_extent_to_text(buf, sizeof(buf), k);
btree_bug(b,
"inconsistent extent pointer %s:\nbucket %zu pin %i prio %i gen %i last_gc %i mark %llu gc_gen %i",
"inconsistent extent pointer %s:\nbucket %zu pin %i prio %i gen %i last_gc %i mark %llu",
buf, PTR_BUCKET_NR(b->c, k, ptr), atomic_read(&g->pin),
g->prio, g->gen, g->last_gc, GC_MARK(g), g->gc_gen);
g->prio, g->gen, g->last_gc, GC_MARK(g));
return true;
}

View File

@ -635,7 +635,7 @@ static void prio_read(struct cache *ca, uint64_t bucket)
}
b->prio = le16_to_cpu(d->prio);
b->gen = b->last_gc = b->gc_gen = d->gen;
b->gen = b->last_gc = d->gen;
}
}