bcachefs: allocate_dropping_locks()

Add two new helpers for allocating memory with btree locks held: The
idea is to first try the allocation with GFP_NOWAIT|__GFP_NOWARN, then
if that fails - unlock, retry with GFP_KERNEL, and then call
trans_relock().

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2023-05-28 03:44:38 -04:00
parent 3ebfc8fe95
commit d95dd378c2
3 changed files with 31 additions and 19 deletions

View File

@ -859,6 +859,32 @@ __bch2_btree_iter_peek_upto_and_restart(struct btree_trans *trans,
bch2_trans_unlock(_trans); \
_do ?: bch2_trans_relock(_trans); \
})
#define allocate_dropping_locks_errcode(_trans, _do) \
({ \
gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN; \
int _ret = _do; \
\
if (bch2_err_matches(_ret, ENOMEM)) { \
_gfp = GFP_KERNEL; \
_ret = drop_locks_do(trans, _do); \
} \
_ret; \
})
#define allocate_dropping_locks(_trans, _ret, _do) \
({ \
gfp_t _gfp = GFP_NOWAIT|__GFP_NOWARN; \
typeof(_do) _p = _do; \
\
_ret = 0; \
if (unlikely(!_p)) { \
_gfp = GFP_KERNEL; \
_ret = drop_locks_do(trans, ((_p = _do), 0)); \
} \
_p; \
})
/* new multiple iterator interface: */
void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);

View File

@ -264,15 +264,8 @@ bkey_cached_alloc(struct btree_trans *trans, struct btree_path *path,
return ck;
}
ck = kmem_cache_zalloc(bch2_key_cache, GFP_NOWAIT|__GFP_NOWARN);
if (likely(ck))
goto init;
bch2_trans_unlock(trans);
ck = kmem_cache_zalloc(bch2_key_cache, GFP_KERNEL);
ret = bch2_trans_relock(trans);
ck = allocate_dropping_locks(trans, ret,
kmem_cache_zalloc(bch2_key_cache, _gfp));
if (ret) {
kmem_cache_free(bch2_key_cache, ck);
return ERR_PTR(ret);
@ -280,7 +273,7 @@ bkey_cached_alloc(struct btree_trans *trans, struct btree_path *path,
if (!ck)
return NULL;
init:
INIT_LIST_HEAD(&ck->list);
bch2_btree_lock_init(&ck->c, pcpu_readers ? SIX_LOCK_INIT_PCPU : 0);

View File

@ -578,15 +578,8 @@ static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp)
static int ec_stripe_mem_alloc(struct btree_trans *trans,
struct btree_iter *iter)
{
size_t idx = iter->pos.offset;
if (!__ec_stripe_mem_alloc(trans->c, idx, GFP_NOWAIT|__GFP_NOWARN))
return 0;
bch2_trans_unlock(trans);
return __ec_stripe_mem_alloc(trans->c, idx, GFP_KERNEL) ?:
bch2_trans_relock(trans);
return allocate_dropping_locks_errcode(trans,
__ec_stripe_mem_alloc(trans->c, iter->pos.offset, _gfp));
}
/*