diff options
Diffstat (limited to 'kernel/bpf/memalloc.c')
| -rw-r--r-- | kernel/bpf/memalloc.c | 94 |
1 files changed, 90 insertions, 4 deletions
diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 9c49ae53deaf..cf1941516643 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -459,8 +459,7 @@ static void notrace irq_work_raise(struct bpf_mem_cache *c) * Typical case will be between 11K and 116K closer to 11K. * bpf progs can and should share bpf_mem_cache when possible. */ - -static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) +static void init_refill_work(struct bpf_mem_cache *c) { init_irq_work(&c->refill_work, bpf_mem_refill); if (c->unit_size <= 256) { @@ -476,7 +475,10 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) c->high_watermark = max(96 * 256 / c->unit_size, 3); } c->batch = max((c->high_watermark - c->low_watermark) / 4 * 3, 1); +} +static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) +{ /* To avoid consuming memory assume that 1st run of bpf * prog won't be doing more than 4 map_update_elem from * irq disabled region @@ -484,6 +486,31 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) alloc_bulk(c, c->unit_size <= 256 ? 4 : 1, cpu_to_node(cpu), false); } +static int check_obj_size(struct bpf_mem_cache *c, unsigned int idx) +{ + struct llist_node *first; + unsigned int obj_size; + + /* For per-cpu allocator, the size of free objects in free list doesn't + * match with unit_size and now there is no way to get the size of + * per-cpu pointer saved in free object, so just skip the checking. + */ + if (c->percpu_size) + return 0; + + first = c->free_llist.first; + if (!first) + return 0; + + obj_size = ksize(first); + if (obj_size != c->unit_size) { + WARN_ONCE(1, "bpf_mem_cache[%u]: unexpected object size %u, expect %u\n", + idx, obj_size, c->unit_size); + return -EINVAL; + } + return 0; +} + /* When size != 0 bpf_mem_cache for each cpu. * This is typical bpf hash map use case when all elements have equal size. * @@ -494,10 +521,10 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) { static u16 sizes[NUM_CACHES] = {96, 192, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096}; + int cpu, i, err, unit_size, percpu_size = 0; struct bpf_mem_caches *cc, __percpu *pcc; struct bpf_mem_cache *c, __percpu *pc; struct obj_cgroup *objcg = NULL; - int cpu, i, unit_size, percpu_size = 0; if (size) { pc = __alloc_percpu_gfp(sizeof(*pc), 8, GFP_KERNEL); @@ -521,6 +548,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) c->objcg = objcg; c->percpu_size = percpu_size; c->tgt = c; + init_refill_work(c); prefill_mem_cache(c, cpu); } ma->cache = pc; @@ -534,6 +562,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) pcc = __alloc_percpu_gfp(sizeof(*cc), 8, GFP_KERNEL); if (!pcc) return -ENOMEM; + err = 0; #ifdef CONFIG_MEMCG_KMEM objcg = get_obj_cgroup_from_current(); #endif @@ -544,11 +573,30 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) c->unit_size = sizes[i]; c->objcg = objcg; c->tgt = c; + + init_refill_work(c); + /* Another bpf_mem_cache will be used when allocating + * c->unit_size in bpf_mem_alloc(), so doesn't prefill + * for the bpf_mem_cache because these free objects will + * never be used. + */ + if (i != bpf_mem_cache_idx(c->unit_size)) + continue; prefill_mem_cache(c, cpu); + err = check_obj_size(c, i); + if (err) + goto out; } } + +out: ma->caches = pcc; - return 0; + /* refill_work is either zeroed or initialized, so it is safe to + * call irq_work_sync(). + */ + if (err) + bpf_mem_alloc_destroy(ma); + return err; } static void drain_mem_cache(struct bpf_mem_cache *c) @@ -916,3 +964,41 @@ void notrace *bpf_mem_cache_alloc_flags(struct bpf_mem_alloc *ma, gfp_t flags) return !ret ? NULL : ret + LLIST_NODE_SZ; } + +/* Most of the logic is taken from setup_kmalloc_cache_index_table() */ +static __init int bpf_mem_cache_adjust_size(void) +{ + unsigned int size, index; + + /* Normally KMALLOC_MIN_SIZE is 8-bytes, but it can be + * up-to 256-bytes. + */ + size = KMALLOC_MIN_SIZE; + if (size <= 192) + index = size_index[(size - 1) / 8]; + else + index = fls(size - 1) - 1; + for (size = 8; size < KMALLOC_MIN_SIZE && size <= 192; size += 8) + size_index[(size - 1) / 8] = index; + + /* The minimal alignment is 64-bytes, so disable 96-bytes cache and + * use 128-bytes cache instead. + */ + if (KMALLOC_MIN_SIZE >= 64) { + index = size_index[(128 - 1) / 8]; + for (size = 64 + 8; size <= 96; size += 8) + size_index[(size - 1) / 8] = index; + } + + /* The minimal alignment is 128-bytes, so disable 192-bytes cache and + * use 256-bytes cache instead. + */ + if (KMALLOC_MIN_SIZE >= 128) { + index = fls(256 - 1) - 1; + for (size = 128 + 8; size <= 192; size += 8) + size_index[(size - 1) / 8] = index; + } + + return 0; +} +subsys_initcall(bpf_mem_cache_adjust_size); |