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authorJonathan Corbet <corbet@lwn.net>2016-08-07 15:13:00 -0600
committerJonathan Corbet <corbet@lwn.net>2016-08-18 17:41:27 -0600
commit758f726e7f7c5a09d8627e6e6ad914e568b31a5c (patch)
tree9a2c1a7b211ab46de6f93ab15ded3a5bd5ba15fa /Documentation
parentd228af5bcb60fda50f8b3a100c0539c4994df040 (diff)
docs: sphinxify kcov.txt and move to dev-tools
Another document added to the dev-tools collection. Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/dev-tools/kcov.rst (renamed from Documentation/kcov.txt)84
-rw-r--r--Documentation/dev-tools/tools.rst1
2 files changed, 43 insertions, 42 deletions
diff --git a/Documentation/kcov.txt b/Documentation/dev-tools/kcov.rst
index 779ff4ab1c1d..aca0e27ca197 100644
--- a/Documentation/kcov.txt
+++ b/Documentation/dev-tools/kcov.rst
@@ -12,38 +12,38 @@ To achieve this goal it does not collect coverage in soft/hard interrupts
and instrumentation of some inherently non-deterministic parts of kernel is
disbled (e.g. scheduler, locking).
-Usage:
-======
+Usage
+-----
-Configure kernel with:
+Configure the kernel with::
CONFIG_KCOV=y
CONFIG_KCOV requires gcc built on revision 231296 or later.
-Profiling data will only become accessible once debugfs has been mounted:
+Profiling data will only become accessible once debugfs has been mounted::
mount -t debugfs none /sys/kernel/debug
-The following program demonstrates kcov usage from within a test program:
-
-#include <stdio.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <unistd.h>
-#include <fcntl.h>
-
-#define KCOV_INIT_TRACE _IOR('c', 1, unsigned long)
-#define KCOV_ENABLE _IO('c', 100)
-#define KCOV_DISABLE _IO('c', 101)
-#define COVER_SIZE (64<<10)
-
-int main(int argc, char **argv)
-{
+The following program demonstrates kcov usage from within a test program::
+
+ #include <stdio.h>
+ #include <stddef.h>
+ #include <stdint.h>
+ #include <stdlib.h>
+ #include <sys/types.h>
+ #include <sys/stat.h>
+ #include <sys/ioctl.h>
+ #include <sys/mman.h>
+ #include <unistd.h>
+ #include <fcntl.h>
+
+ #define KCOV_INIT_TRACE _IOR('c', 1, unsigned long)
+ #define KCOV_ENABLE _IO('c', 100)
+ #define KCOV_DISABLE _IO('c', 101)
+ #define COVER_SIZE (64<<10)
+
+ int main(int argc, char **argv)
+ {
int fd;
unsigned long *cover, n, i;
@@ -83,24 +83,24 @@ int main(int argc, char **argv)
if (close(fd))
perror("close"), exit(1);
return 0;
-}
-
-After piping through addr2line output of the program looks as follows:
-
-SyS_read
-fs/read_write.c:562
-__fdget_pos
-fs/file.c:774
-__fget_light
-fs/file.c:746
-__fget_light
-fs/file.c:750
-__fget_light
-fs/file.c:760
-__fdget_pos
-fs/file.c:784
-SyS_read
-fs/read_write.c:562
+ }
+
+After piping through addr2line output of the program looks as follows::
+
+ SyS_read
+ fs/read_write.c:562
+ __fdget_pos
+ fs/file.c:774
+ __fget_light
+ fs/file.c:746
+ __fget_light
+ fs/file.c:750
+ __fget_light
+ fs/file.c:760
+ __fdget_pos
+ fs/file.c:784
+ SyS_read
+ fs/read_write.c:562
If a program needs to collect coverage from several threads (independently),
it needs to open /sys/kernel/debug/kcov in each thread separately.
diff --git a/Documentation/dev-tools/tools.rst b/Documentation/dev-tools/tools.rst
index d4bbda319e79..9dcd0236a1ff 100644
--- a/Documentation/dev-tools/tools.rst
+++ b/Documentation/dev-tools/tools.rst
@@ -16,3 +16,4 @@ whole; patches welcome!
coccinelle
sparse
+ kcov