// SPDX-License-Identifier: GPL-2.0
/*
- * Primary bucket allocation code
- *
* Copyright 2012 Google, Inc.
*
- * Allocation in bcache is done in terms of buckets:
- *
- * Each bucket has associated an 8 bit gen; this gen corresponds to the gen in
- * btree pointers - they must match for the pointer to be considered valid.
- *
- * Thus (assuming a bucket has no dirty data or metadata in it) we can reuse a
- * bucket simply by incrementing its gen.
- *
- * The gens (along with the priorities; it's really the gens are important but
- * the code is named as if it's the priorities) are written in an arbitrary list
- * of buckets on disk, with a pointer to them in the journal header.
- *
- * When we invalidate a bucket, we have to write its new gen to disk and wait
- * for that write to complete before we use it - otherwise after a crash we
- * could have pointers that appeared to be good but pointed to data that had
- * been overwritten.
- *
- * Since the gens and priorities are all stored contiguously on disk, we can
- * batch this up: We fill up the free_inc list with freshly invalidated buckets,
- * call prio_write(), and when prio_write() finishes we pull buckets off the
- * free_inc list and optionally discard them.
- *
- * free_inc isn't the only freelist - if it was, we'd often have to sleep while
- * priorities and gens were being written before we could allocate. c->free is a
- * smaller freelist, and buckets on that list are always ready to be used.
- *
- * If we've got discards enabled, that happens when a bucket moves from the
- * free_inc list to the free list.
- *
- * It's important to ensure that gens don't wrap around - with respect to
- * either the oldest gen in the btree or the gen on disk. This is quite
- * difficult to do in practice, but we explicitly guard against it anyways - if
- * a bucket is in danger of wrapping around we simply skip invalidating it that
- * time around, and we garbage collect or rewrite the priorities sooner than we
- * would have otherwise.
+ * Foreground allocator code: allocate buckets from freelist, and allocate in
+ * sector granularity from writepoints.
*
* bch2_bucket_alloc() allocates a single bucket from a specific device.
*
* bch2_bucket_alloc_set() allocates one or more buckets from different devices
* in a given filesystem.
- *
- * invalidate_buckets() drives all the processes described above. It's called
- * from bch2_bucket_alloc() and a few other places that need to make sure free
- * buckets are ready.
- *
- * invalidate_buckets_(lru|fifo)() find buckets that are available to be
- * invalidated, and then invalidate them and stick them on the free_inc list -
- * in either lru or fifo order.
*/
#include "bcachefs.h"
percpu_down_read(&c->mark_lock);
spin_lock(&ob->lock);
- bch2_mark_alloc_bucket(c, ca, PTR_BUCKET_NR(ca, &ob->ptr),
- false, gc_pos_alloc(c, ob), 0);
+ bch2_mark_alloc_bucket(c, ca, PTR_BUCKET_NR(ca, &ob->ptr), false);
ob->valid = false;
ob->type = 0;
spin_lock(&c->freelist_lock);
ob->freelist = c->open_buckets_freelist;
c->open_buckets_freelist = ob - c->open_buckets;
+
c->open_buckets_nr_free++;
+ ca->nr_open_buckets--;
spin_unlock(&c->freelist_lock);
closure_wake_up(&c->open_buckets_wait);
rcu_read_lock();
buckets = bucket_array(ca);
- for (b = ca->mi.first_bucket; b < ca->mi.nbuckets; b++)
- if (is_available_bucket(buckets->b[b].mark))
+ for (b = buckets->first_bucket; b < buckets->nbuckets; b++)
+ if (is_available_bucket(buckets->b[b].mark) &&
+ !buckets->b[b].mark.owned_by_allocator)
goto success;
b = -1;
success:
bool may_alloc_partial,
struct closure *cl)
{
- struct bucket_array *buckets;
struct open_bucket *ob;
- long bucket = 0;
+ long b = 0;
spin_lock(&c->freelist_lock);
return ERR_PTR(-OPEN_BUCKETS_EMPTY);
}
- if (likely(fifo_pop(&ca->free[RESERVE_NONE], bucket)))
+ if (likely(fifo_pop(&ca->free[RESERVE_NONE], b)))
goto out;
switch (reserve) {
case RESERVE_BTREE_MOVINGGC:
case RESERVE_MOVINGGC:
- if (fifo_pop(&ca->free[RESERVE_MOVINGGC], bucket))
+ if (fifo_pop(&ca->free[RESERVE_MOVINGGC], b))
goto out;
break;
default:
trace_bucket_alloc_fail(ca, reserve);
return ERR_PTR(-FREELIST_EMPTY);
out:
- verify_not_on_freelist(c, ca, bucket);
+ verify_not_on_freelist(c, ca, b);
ob = bch2_open_bucket_alloc(c);
spin_lock(&ob->lock);
- buckets = bucket_array(ca);
ob->valid = true;
ob->sectors_free = ca->mi.bucket_size;
ob->alloc_reserve = reserve;
ob->ptr = (struct bch_extent_ptr) {
.type = 1 << BCH_EXTENT_ENTRY_ptr,
- .gen = buckets->b[bucket].mark.gen,
- .offset = bucket_to_sector(ca, bucket),
+ .gen = bucket(ca, b)->mark.gen,
+ .offset = bucket_to_sector(ca, b),
.dev = ca->dev_idx,
};
c->blocked_allocate = 0;
}
+ ca->nr_open_buckets++;
spin_unlock(&c->freelist_lock);
bch2_wake_allocator(ca);
struct dev_stripe_state *stripe)
{
u64 *v = stripe->next_alloc + ca->dev_idx;
- u64 free_space = dev_buckets_free(ca);
+ u64 free_space = dev_buckets_available(ca);
u64 free_space_inv = free_space
? div64_u64(1ULL << 48, free_space)
: 1ULL << 48;
devs_sorted = bch2_dev_alloc_list(c, &wp->stripe, devs_may_alloc);
for (i = 0; i < devs_sorted.nr; i++)
- open_bucket_for_each(c, &h->s->blocks, ob, ec_idx)
+ for (ec_idx = 0; ec_idx < h->s->nr_data; ec_idx++) {
+ if (!h->s->blocks[ec_idx])
+ continue;
+
+ ob = c->open_buckets + h->s->blocks[ec_idx];
if (ob->ptr.dev == devs_sorted.devs[i] &&
- !test_and_set_bit(h->s->data_block_idx[ec_idx],
- h->s->blocks_allocated))
+ !test_and_set_bit(ec_idx, h->s->blocks_allocated))
goto got_bucket;
+ }
goto out_put_head;
got_bucket:
ca = bch_dev_bkey_exists(c, ob->ptr.dev);
- ob->ec_idx = h->s->data_block_idx[ec_idx];
+ ob->ec_idx = ec_idx;
ob->ec = h->s;
add_new_bucket(c, ptrs, devs_may_alloc,
if (!drop && ob->ec) {
mutex_lock(&ob->ec->lock);
- open_bucket_for_each(c, &ob->ec->blocks, ob2, j)
- drop |= ob2->ptr.dev == ca->dev_idx;
- open_bucket_for_each(c, &ob->ec->parity, ob2, j)
+ for (j = 0; j < ob->ec->new_stripe.key.v.nr_blocks; j++) {
+ if (!ob->ec->blocks[j])
+ continue;
+
+ ob2 = c->open_buckets + ob->ec->blocks[j];
drop |= ob2->ptr.dev == ca->dev_idx;
+ }
mutex_unlock(&ob->ec->lock);
}
{
struct write_point *wp;
+ rcu_read_lock();
hlist_for_each_entry_rcu(wp, head, node)
if (wp->write_point == write_point)
- return wp;
-
- return NULL;
+ goto out;
+ wp = NULL;
+out:
+ rcu_read_unlock();
+ return wp;
}
static inline bool too_many_writepoints(struct bch_fs *c, unsigned factor)
projects / bcachefs-tools-debian / blobdiff