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Diffstat (limited to 'kernel/bpf/memalloc.c')
-rw-r--r--kernel/bpf/memalloc.c94
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);