X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=lib%2Fringbuffer%2Fring_buffer_frontend.c;h=82726a17678ecfb097891f3475956a8dd3bda85a;hb=refs%2Fheads%2Fstable-2.7;hp=bc9a7b263a7cc5808a76ae6e5b54b9f796013f39;hpb=e795690f41343b02cb6e78aa5edfe126c072a53c;p=lttng-modules.git

diff --git a/lib/ringbuffer/ring_buffer_frontend.c b/lib/ringbuffer/ring_buffer_frontend.c
index bc9a7b26..82726a17 100644
--- a/lib/ringbuffer/ring_buffer_frontend.c
+++ b/lib/ringbuffer/ring_buffer_frontend.c
@@ -205,7 +205,8 @@ int lib_ring_buffer_create(struct lib_ring_buffer *buf,
 		kzalloc_node(ALIGN(sizeof(*buf->commit_hot)
 				   * chan->backend.num_subbuf,
 				   1 << INTERNODE_CACHE_SHIFT),
-			GFP_KERNEL, cpu_to_node(max(cpu, 0)));
+			GFP_KERNEL | __GFP_NOWARN,
+			cpu_to_node(max(cpu, 0)));
 	if (!buf->commit_hot) {
 		ret = -ENOMEM;
 		goto free_chanbuf;
@@ -215,7 +216,8 @@ int lib_ring_buffer_create(struct lib_ring_buffer *buf,
 		kzalloc_node(ALIGN(sizeof(*buf->commit_cold)
 				   * chan->backend.num_subbuf,
 				   1 << INTERNODE_CACHE_SHIFT),
-			GFP_KERNEL, cpu_to_node(max(cpu, 0)));
+			GFP_KERNEL | __GFP_NOWARN,
+			cpu_to_node(max(cpu, 0)));
 	if (!buf->commit_cold) {
 		ret = -ENOMEM;
 		goto free_commit;
@@ -904,15 +906,6 @@ int lib_ring_buffer_snapshot(struct lib_ring_buffer *buf,
 	unsigned long consumed_cur, write_offset;
 	int finalized;
 
-	/*
-	 * First, ensure we perform a "final" flush onto the stream.  This will
-	 * ensure we create a packet of padding if we encounter an empty
-	 * packet. This ensures the time-stamps right before the snapshot is
-	 * used as end of packet timestamp.
-	 */
-	if (!buf->quiescent)
-		_lib_ring_buffer_switch_remote(buf, SWITCH_FLUSH);
-
 retry:
 	finalized = ACCESS_ONCE(buf->finalized);
 	/*
@@ -1615,11 +1608,17 @@ void lib_ring_buffer_switch_slow(struct lib_ring_buffer *buf, enum switch_mode m
 }
 EXPORT_SYMBOL_GPL(lib_ring_buffer_switch_slow);
 
+struct switch_param {
+	struct lib_ring_buffer *buf;
+	enum switch_mode mode;
+};
+
 static void remote_switch(void *info)
 {
-	struct lib_ring_buffer *buf = info;
+	struct switch_param *param = info;
+	struct lib_ring_buffer *buf = param->buf;
 
-	lib_ring_buffer_switch_slow(buf, SWITCH_ACTIVE);
+	lib_ring_buffer_switch_slow(buf, param->mode);
 }
 
 static void _lib_ring_buffer_switch_remote(struct lib_ring_buffer *buf,
@@ -1628,6 +1627,7 @@ static void _lib_ring_buffer_switch_remote(struct lib_ring_buffer *buf,
 	struct channel *chan = buf->backend.chan;
 	const struct lib_ring_buffer_config *config = &chan->backend.config;
 	int ret;
+	struct switch_param param;
 
 	/*
 	 * With global synchronization we don't need to use the IPI scheme.
@@ -1648,8 +1648,10 @@ static void _lib_ring_buffer_switch_remote(struct lib_ring_buffer *buf,
 	 * switch.
 	 */
 	get_online_cpus();
+	param.buf = buf;
+	param.mode = mode;
 	ret = smp_call_function_single(buf->backend.cpu,
-				 remote_switch, buf, 1);
+				 remote_switch, &param, 1);
 	if (ret) {
 		/* Remote CPU is offline, do it ourself. */
 		lib_ring_buffer_switch_slow(buf, mode);
@@ -1663,6 +1665,13 @@ void lib_ring_buffer_switch_remote(struct lib_ring_buffer *buf)
 }
 EXPORT_SYMBOL_GPL(lib_ring_buffer_switch_remote);
 
+/* Switch sub-buffer even if current sub-buffer is empty. */
+void lib_ring_buffer_switch_remote_empty(struct lib_ring_buffer *buf)
+{
+	_lib_ring_buffer_switch_remote(buf, SWITCH_FLUSH);
+}
+EXPORT_SYMBOL_GPL(lib_ring_buffer_switch_remote_empty);
+
 /*
  * Returns :
  * 0 if ok