percpu: make allocation failures more verbose (f2badb0c) · Commits · 戴 / test

mm/percpu.c

+18 −2

Original line number	Diff line number	Diff line
		@@ -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;
		}

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