Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
To:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        <rostedt@goodmis.org>, <mingo@redhat.com>
CC:     linfeilong <linfeilong@huawei.com>,
        Louhongxiang <louhongxiang@huawei.com>
From:   Zhiqiang Liu <liuzhiqiang26@huawei.com>
Subject: [PATCH] tracing: use free_trace_buffer in allocate_trace_buffers
Message-ID: <65f0702d-07f6-08de-2a07-4c50af56a67b@huawei.com>
Date:   Wed, 20 Jul 2022 10:46:48 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.2.2
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk


In allocate_trace_buffers(), if allocating tr->max_buffer
fails, we can directly call free_trace_buffer to free
tr->array_buffer.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
---
 kernel/trace/trace.c | 25 +++++++++++--------------
 1 file changed, 11 insertions(+), 14 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index b8dd54627075..883c8e9987f6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -9101,6 +9101,16 @@ allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size
 	return 0;
 }

+static void free_trace_buffer(struct array_buffer *buf)
+{
+	if (buf->buffer) {
+		ring_buffer_free(buf->buffer);
+		buf->buffer = NULL;
+		free_percpu(buf->data);
+		buf->data = NULL;
+	}
+}
+
 static int allocate_trace_buffers(struct trace_array *tr, int size)
 {
 	int ret;
@@ -9113,10 +9123,7 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
 	ret = allocate_trace_buffer(tr, &tr->max_buffer,
 				    allocate_snapshot ? size : 1);
 	if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) {
-		ring_buffer_free(tr->array_buffer.buffer);
-		tr->array_buffer.buffer = NULL;
-		free_percpu(tr->array_buffer.data);
-		tr->array_buffer.data = NULL;
+		free_trace_buffer(&tr->array_buffer);
 		return -ENOMEM;
 	}
 	tr->allocated_snapshot = allocate_snapshot;
@@ -9131,16 +9138,6 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
 	return 0;
 }

-static void free_trace_buffer(struct array_buffer *buf)
-{
-	if (buf->buffer) {
-		ring_buffer_free(buf->buffer);
-		buf->buffer = NULL;
-		free_percpu(buf->data);
-		buf->data = NULL;
-	}
-}
-
 static void free_trace_buffers(struct trace_array *tr)
 {
 	if (!tr)
-- 
2.33.0