diff options
| -rw-r--r-- | mm/percpu.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/mm/percpu.c b/mm/percpu.c index 83617ca3ba52..4a048abad043 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1043,7 +1043,9 @@ static struct pcpu_chunk *alloc_pcpu_chunk(void) */ static void *pcpu_alloc(size_t size, size_t align, bool reserved) { + static int warn_limit = 10; struct pcpu_chunk *chunk; + const char *err; int slot, off; if (unlikely(!size || size > PCPU_MIN_UNIT_SIZE || align > PAGE_SIZE)) { @@ -1059,11 +1061,14 @@ static void *pcpu_alloc(size_t size, size_t align, bool reserved) if (reserved && pcpu_reserved_chunk) { chunk = pcpu_reserved_chunk; if (size > chunk->contig_hint || - pcpu_extend_area_map(chunk) < 0) + pcpu_extend_area_map(chunk) < 0) { + err = "failed to extend area map of reserved chunk"; goto fail_unlock; + } off = pcpu_alloc_area(chunk, size, align); if (off >= 0) goto area_found; + err = "alloc from reserved chunk failed"; goto fail_unlock; } @@ -1080,6 +1085,7 @@ restart: case 1: goto restart; /* pcpu_lock dropped, restart */ default: + err = "failed to extend area map"; goto fail_unlock; } @@ -1093,8 +1099,10 @@ restart: spin_unlock_irq(&pcpu_lock); chunk = alloc_pcpu_chunk(); - if (!chunk) + if (!chunk) { + err = "failed to allocate new chunk"; goto fail_unlock_mutex; + } spin_lock_irq(&pcpu_lock); pcpu_chunk_relocate(chunk, -1); @@ -1107,6 +1115,7 @@ area_found: if (pcpu_populate_chunk(chunk, off, size)) { spin_lock_irq(&pcpu_lock); pcpu_free_area(chunk, off); + err = "failed to populate"; goto fail_unlock; } @@ -1119,6 +1128,13 @@ fail_unlock: spin_unlock_irq(&pcpu_lock); fail_unlock_mutex: mutex_unlock(&pcpu_alloc_mutex); + if (warn_limit) { + pr_warning("PERCPU: allocation failed, size=%zu align=%zu, " + "%s\n", size, align, err); + dump_stack(); + if (!--warn_limit) + pr_info("PERCPU: limit reached, disable warning\n"); + } return NULL; } |