linux/kernel/gcov/gcov.h

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gcov: add gcov profiling infrastructure Enable the use of GCC's coverage testing tool gcov [1] with the Linux kernel. gcov may be useful for: * debugging (has this code been reached at all?) * test improvement (how do I change my test to cover these lines?) * minimizing kernel configurations (do I need this option if the associated code is never run?) The profiling patch incorporates the following changes: * change kbuild to include profiling flags * provide functions needed by profiling code * present profiling data as files in debugfs Note that on some architectures, enabling gcc's profiling option "-fprofile-arcs" for the entire kernel may trigger compile/link/ run-time problems, some of which are caused by toolchain bugs and others which require adjustment of architecture code. For this reason profiling the entire kernel is initially restricted to those architectures for which it is known to work without changes. This restriction can be lifted once an architecture has been tested and found compatible with gcc's profiling. Profiling of single files or directories is still available on all platforms (see config help text). [1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 07:28:08 +08:00
/*
* Profiling infrastructure declarations.
*
* This file is based on gcc-internal definitions. Data structures are
* defined to be compatible with gcc counterparts. For a better
* understanding, refer to gcc source: gcc/gcov-io.h.
*
* Copyright IBM Corp. 2009
* Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
*
* Uses gcc-internal data definitions.
*/
#ifndef GCOV_H
#define GCOV_H GCOV_H
#include <linux/types.h>
/*
* Profiling data types used for gcc 3.4 and above - these are defined by
* gcc and need to be kept as close to the original definition as possible to
* remain compatible.
*/
#define GCOV_DATA_MAGIC ((unsigned int) 0x67636461)
#define GCOV_TAG_FUNCTION ((unsigned int) 0x01000000)
#define GCOV_TAG_COUNTER_BASE ((unsigned int) 0x01a10000)
#define GCOV_TAG_FOR_COUNTER(count) \
(GCOV_TAG_COUNTER_BASE + ((unsigned int) (count) << 17))
#if BITS_PER_LONG >= 64
typedef long gcov_type;
#else
typedef long long gcov_type;
#endif
/* Opaque gcov_info. The gcov structures can change as for example in gcc 4.7 so
* we cannot use full definition here and they need to be placed in gcc specific
* implementation of gcov. This also means no direct access to the members in
* generic code and usage of the interface below.*/
struct gcov_info;
/* Interface to access gcov_info data */
const char *gcov_info_filename(struct gcov_info *info);
unsigned int gcov_info_version(struct gcov_info *info);
struct gcov_info *gcov_info_next(struct gcov_info *info);
void gcov_info_link(struct gcov_info *info);
void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info);
gcov: add gcov profiling infrastructure Enable the use of GCC's coverage testing tool gcov [1] with the Linux kernel. gcov may be useful for: * debugging (has this code been reached at all?) * test improvement (how do I change my test to cover these lines?) * minimizing kernel configurations (do I need this option if the associated code is never run?) The profiling patch incorporates the following changes: * change kbuild to include profiling flags * provide functions needed by profiling code * present profiling data as files in debugfs Note that on some architectures, enabling gcc's profiling option "-fprofile-arcs" for the entire kernel may trigger compile/link/ run-time problems, some of which are caused by toolchain bugs and others which require adjustment of architecture code. For this reason profiling the entire kernel is initially restricted to those architectures for which it is known to work without changes. This restriction can be lifted once an architecture has been tested and found compatible with gcc's profiling. Profiling of single files or directories is still available on all platforms (see config help text). [1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 07:28:08 +08:00
/* Base interface. */
enum gcov_action {
GCOV_ADD,
GCOV_REMOVE,
};
void gcov_event(enum gcov_action action, struct gcov_info *info);
void gcov_enable_events(void);
/* Iterator control. */
struct seq_file;
struct gcov_iterator;
struct gcov_iterator *gcov_iter_new(struct gcov_info *info);
void gcov_iter_free(struct gcov_iterator *iter);
void gcov_iter_start(struct gcov_iterator *iter);
int gcov_iter_next(struct gcov_iterator *iter);
int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq);
struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter);
/* gcov_info control. */
void gcov_info_reset(struct gcov_info *info);
int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2);
void gcov_info_add(struct gcov_info *dest, struct gcov_info *source);
struct gcov_info *gcov_info_dup(struct gcov_info *info);
void gcov_info_free(struct gcov_info *info);
struct gcov_link {
enum {
OBJ_TREE,
SRC_TREE,
} dir;
const char *ext;
};
extern const struct gcov_link gcov_link[];
#endif /* GCOV_H */