From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Wed, 29 Apr 2020 01:40:12 +0000 (-0400)
Subject: kerner-ctl: add RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK
X-Git-Tag: v2.11.5~35
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=88be8d77519f987de53a8f1f17aeec296dddb283;p=lttng-tools.git

kerner-ctl: add RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK

Add a wrapper for RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK
which gets the next metadata subbuffer and returns a boolean flag
indicating whether the metadata is guaranteed to be in a consistent
state at the end of this sub-buffer (can be parsed).

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I13fbdfe51c3c4ef04581409e0fbc9837ed6d555d
---

diff --git a/src/common/kernel-ctl/kernel-ctl.c b/src/common/kernel-ctl/kernel-ctl.c
index 14d96b577..2efbfa19d 100644
--- a/src/common/kernel-ctl/kernel-ctl.c
+++ b/src/common/kernel-ctl/kernel-ctl.c
@@ -453,6 +453,13 @@ int kernctl_buffer_flush_empty(int fd)
 	return LTTNG_IOCTL_CHECK(fd, RING_BUFFER_FLUSH_EMPTY);
 }
 
+int kernctl_get_next_subbuf_metadata_check(int fd, bool *consistent)
+{
+	return LTTNG_IOCTL_NO_CHECK(fd,
+			RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK,
+			consistent);
+}
+
 /* returns the version of the metadata. */
 int kernctl_get_metadata_version(int fd, uint64_t *version)
 {
diff --git a/src/common/kernel-ctl/kernel-ctl.h b/src/common/kernel-ctl/kernel-ctl.h
index 053e7df63..fb4838cc8 100644
--- a/src/common/kernel-ctl/kernel-ctl.h
+++ b/src/common/kernel-ctl/kernel-ctl.h
@@ -19,6 +19,8 @@
 #ifndef _LTTNG_KERNEL_CTL_H
 #define _LTTNG_KERNEL_CTL_H
 
+#include <stdbool.h>
+
 #include <lttng/lttng.h>
 #include <common/lttng-kernel.h>
 #include <common/lttng-kernel-old.h>
@@ -99,6 +101,7 @@ int kernctl_buffer_flush(int fd);
 int kernctl_buffer_flush_empty(int fd);
 int kernctl_get_metadata_version(int fd, uint64_t *version);
 int kernctl_metadata_cache_dump(int fd);
+int kernctl_get_next_subbuf_metadata_check(int fd, bool *consistent);
 
 /* index */
 int kernctl_get_timestamp_begin(int fd, uint64_t *timestamp_begin);
diff --git a/src/common/kernel-ctl/kernel-ioctl.h b/src/common/kernel-ctl/kernel-ioctl.h
index 8d39abbe3..8a36f6352 100644
--- a/src/common/kernel-ctl/kernel-ioctl.h
+++ b/src/common/kernel-ctl/kernel-ioctl.h
@@ -64,6 +64,7 @@
  * so it can be read again.
  */
 #define RING_BUFFER_METADATA_CACHE_DUMP    	_IO(0xF6, 0x10)
+#define RING_RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK _IOR(0xF6, 0x12, uint32_t)
 
 /* returns the timestamp begin of the current sub-buffer */
 #define LTTNG_RING_BUFFER_GET_TIMESTAMP_BEGIN     _IOR(0xF6, 0x20, uint64_t)