diff options
| -rw-r--r-- | mm/percpu.c | 73 |
1 files changed, 44 insertions, 29 deletions
diff --git a/mm/percpu.c b/mm/percpu.c index 0c59684f1ff2..9903830aaebb 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -112,7 +112,7 @@ struct pcpu_chunk { int map_used; /* # of map entries used before the sentry */ int map_alloc; /* # of map entries allocated */ int *map; /* allocation map */ - struct work_struct map_extend_work;/* async ->map[] extension */ + struct list_head map_extend_list;/* on pcpu_map_extend_chunks */ void *data; /* chunk data */ int first_free; /* no free below this */ @@ -162,10 +162,13 @@ static struct pcpu_chunk *pcpu_reserved_chunk; static int pcpu_reserved_chunk_limit; static DEFINE_SPINLOCK(pcpu_lock); /* all internal data structures */ -static DEFINE_MUTEX(pcpu_alloc_mutex); /* chunk create/destroy, [de]pop */ +static DEFINE_MUTEX(pcpu_alloc_mutex); /* chunk create/destroy, [de]pop, map ext */ static struct list_head *pcpu_slot __read_mostly; /* chunk list slots */ +/* chunks which need their map areas extended, protected by pcpu_lock */ +static LIST_HEAD(pcpu_map_extend_chunks); + /* * The number of empty populated pages, protected by pcpu_lock. The * reserved chunk doesn't contribute to the count. @@ -395,13 +398,19 @@ static int pcpu_need_to_extend(struct pcpu_chunk *chunk, bool is_atomic) { int margin, new_alloc; + lockdep_assert_held(&pcpu_lock); + if (is_atomic) { margin = 3; if (chunk->map_alloc < - chunk->map_used + PCPU_ATOMIC_MAP_MARGIN_LOW && - pcpu_async_enabled) - schedule_work(&chunk->map_extend_work); + chunk->map_used + PCPU_ATOMIC_MAP_MARGIN_LOW) { + if (list_empty(&chunk->map_extend_list)) { + list_add_tail(&chunk->map_extend_list, + &pcpu_map_extend_chunks); + pcpu_schedule_balance_work(); + } + } } else { margin = PCPU_ATOMIC_MAP_MARGIN_HIGH; } @@ -435,6 +444,8 @@ static int pcpu_extend_area_map(struct pcpu_chunk *chunk, int new_alloc) size_t old_size = 0, new_size = new_alloc * sizeof(new[0]); unsigned long flags; + lockdep_assert_held(&pcpu_alloc_mutex); + new = pcpu_mem_zalloc(new_size); if (!new) return -ENOMEM; @@ -467,20 +478,6 @@ out_unlock: return 0; } -static void pcpu_map_extend_workfn(struct work_struct *work) -{ - struct pcpu_chunk *chunk = container_of(work, struct pcpu_chunk, - map_extend_work); - int new_alloc; - - spin_lock_irq(&pcpu_lock); - new_alloc = pcpu_need_to_extend(chunk, false); - spin_unlock_irq(&pcpu_lock); - - if (new_alloc) - pcpu_extend_area_map(chunk, new_alloc); -} - /** * pcpu_fit_in_area - try to fit the requested allocation in a candidate area * @chunk: chunk the candidate area belongs to @@ -740,7 +737,7 @@ static struct pcpu_chunk *pcpu_alloc_chunk(void) chunk->map_used = 1; INIT_LIST_HEAD(&chunk->list); - INIT_WORK(&chunk->map_extend_work, pcpu_map_extend_workfn); + INIT_LIST_HEAD(&chunk->map_extend_list); chunk->free_size = pcpu_unit_size; chunk->contig_hint = pcpu_unit_size; @@ -895,6 +892,9 @@ static void __percpu *pcpu_alloc(size_t size, size_t align, bool reserved, return NULL; } + if (!is_atomic) + mutex_lock(&pcpu_alloc_mutex); + spin_lock_irqsave(&pcpu_lock, flags); /* serve reserved allocations from the reserved chunk if available */ @@ -967,12 +967,9 @@ restart: if (is_atomic) goto fail; - mutex_lock(&pcpu_alloc_mutex); - if (list_empty(&pcpu_slot[pcpu_nr_slots - 1])) { chunk = pcpu_create_chunk(); if (!chunk) { - mutex_unlock(&pcpu_alloc_mutex); err = "failed to allocate new chunk"; goto fail; } @@ -983,7 +980,6 @@ restart: spin_lock_irqsave(&pcpu_lock, flags); } - mutex_unlock(&pcpu_alloc_mutex); goto restart; area_found: @@ -993,8 +989,6 @@ area_found: if (!is_atomic) { int page_start, page_end, rs, re; - mutex_lock(&pcpu_alloc_mutex); - page_start = PFN_DOWN(off); page_end = PFN_UP(off + size); @@ -1005,7 +999,6 @@ area_found: spin_lock_irqsave(&pcpu_lock, flags); if (ret) { - mutex_unlock(&pcpu_alloc_mutex); pcpu_free_area(chunk, off, &occ_pages); err = "failed to populate"; goto fail_unlock; @@ -1045,6 +1038,8 @@ fail: /* see the flag handling in pcpu_blance_workfn() */ pcpu_atomic_alloc_failed = true; pcpu_schedule_balance_work(); + } else { + mutex_unlock(&pcpu_alloc_mutex); } return NULL; } @@ -1129,6 +1124,7 @@ static void pcpu_balance_workfn(struct work_struct *work) if (chunk == list_first_entry(free_head, struct pcpu_chunk, list)) continue; + list_del_init(&chunk->map_extend_list); list_move(&chunk->list, &to_free); } @@ -1146,6 +1142,25 @@ static void pcpu_balance_workfn(struct work_struct *work) pcpu_destroy_chunk(chunk); } + /* service chunks which requested async area map extension */ + do { + int new_alloc = 0; + + spin_lock_irq(&pcpu_lock); + + chunk = list_first_entry_or_null(&pcpu_map_extend_chunks, + struct pcpu_chunk, map_extend_list); + if (chunk) { + list_del_init(&chunk->map_extend_list); + new_alloc = pcpu_need_to_extend(chunk, false); + } + + spin_unlock_irq(&pcpu_lock); + + if (new_alloc) + pcpu_extend_area_map(chunk, new_alloc); + } while (chunk); + /* * Ensure there are certain number of free populated pages for * atomic allocs. Fill up from the most packed so that atomic @@ -1644,7 +1659,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, */ schunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0); INIT_LIST_HEAD(&schunk->list); - INIT_WORK(&schunk->map_extend_work, pcpu_map_extend_workfn); + INIT_LIST_HEAD(&schunk->map_extend_list); schunk->base_addr = base_addr; schunk->map = smap; schunk->map_alloc = ARRAY_SIZE(smap); @@ -1673,7 +1688,7 @@ int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, if (dyn_size) { dchunk = memblock_virt_alloc(pcpu_chunk_struct_size, 0); INIT_LIST_HEAD(&dchunk->list); - INIT_WORK(&dchunk->map_extend_work, pcpu_map_extend_workfn); + INIT_LIST_HEAD(&dchunk->map_extend_list); dchunk->base_addr = base_addr; dchunk->map = dmap; dchunk->map_alloc = ARRAY_SIZE(dmap); |