kmemleak: record accurate early log buffer count and report when exceeded

In log_early function, crt_early_log should also count once when
'crt_early_log >= ARRAY_SIZE(early_log)'.  Otherwise the reported count
from kmemleak_init is one less than 'actual number'.

Then, in kmemleak_init, if early_log buffer size equal actual number,
kmemleak will init sucessful, so change warning condition to
'crt_early_log > ARRAY_SIZE(early_log)'.

Signed-off-by: Wang Kai <morgan.wang@huawei.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/kmemleak.c

@@ -838,6 +838,7 @@ static void __init log_early(int op_type, const void *ptr, size_t size,
 	}
 
 	if (crt_early_log >= ARRAY_SIZE(early_log)) {
+		crt_early_log++;
 		kmemleak_disable();
 		return;
 	}
@@ -1882,7 +1883,7 @@ void __init kmemleak_init(void)
 	object_cache = KMEM_CACHE(kmemleak_object, SLAB_NOLEAKTRACE);
 	scan_area_cache = KMEM_CACHE(kmemleak_scan_area, SLAB_NOLEAKTRACE);
 
-	if (crt_early_log >= ARRAY_SIZE(early_log))
+	if (crt_early_log > ARRAY_SIZE(early_log))
 		pr_warning("Early log buffer exceeded (%d), please increase "
 			   "DEBUG_KMEMLEAK_EARLY_LOG_SIZE\n", crt_early_log);