linux/Documentation
Peter Oberparleiter 2521f2c228 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 13:03:57 -07:00
..
ABI Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block 2009-06-11 11:10:35 -07:00
accounting Documentation/accounting/getdelays.c intialize the variable before using it 2009-06-16 19:47:51 -07:00
acpi
aoe
arm [ARM] S3C24XX: GPIO: Change to macros for GPIO numbering 2009-05-18 16:26:03 +01:00
auxdisplay
blackfin
block trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
blockdev mflash: initial support 2009-04-07 08:12:38 +02:00
cdrom debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
cgroups memcg: add interface to reset limits 2009-06-18 13:03:48 -07:00
connector Documentation/connector/cn_test.c comment unused cn_test_want_notify() 2009-06-18 13:03:46 -07:00
console
cpu-freq [CPUFREQ] minor correction to cpu-freq documentation 2009-06-15 11:49:42 -04:00
cpuidle
cris
crypto
development-process docs: Encourage better changelogs in the development process document 2009-06-04 10:32:49 -06:00
device-mapper
DocBook debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
driver-model Driver Core: Warn driver authors about adding device attributes 2009-06-15 21:30:23 -07:00
dvb V4L/DVB (11962): dvb: Fix broken link in get_dvb_firmware for nxt2004 (A180) 2009-06-16 19:07:39 -03:00
early-userspace
fault-injection debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
fb Documentation/fb/vesafb.txt: fix typo 2009-06-16 19:47:58 -07:00
filesystems isofs: let mode and dmode mount options override rock ridge mode setting 2009-06-18 13:03:45 -07:00
firmware_class driver core: fix documentation of request_firmware_nowait 2009-06-15 21:30:24 -07:00
frv
hwmon hwmon: (f71882fg) Add support for the F71858F 2009-06-15 18:39:52 +02:00
i2c i2c-viapro: Add new PCI device ID for VX855 2009-06-15 18:01:49 +02:00
i2o
ia64 trivial: Fix misspelling of firmware 2009-03-30 15:21:59 +02:00
ide ide: preserve Host Protected Area by default (v2) 2009-06-07 13:52:52 +02:00
infiniband IPoIB: Document newish features 2009-04-08 13:52:01 -07:00
input Input: multitouch - augment event semantics documentation 2009-05-23 09:53:26 -07:00
ioctl V4L/DVB (10870a): remove all references for video_decoder.h 2009-03-30 12:43:15 -03:00
isdn isdn: extend INTERFACE.CAPI document 2009-06-08 00:45:52 -07:00
ja_JP
kbuild kconfig: resort the documentation of the environment variables 2009-06-09 22:37:47 +02:00
kdump trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
ko_KR
laptops trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
lguest lguest: add support for indirect ring entries 2009-06-12 22:27:13 +09:30
m68k
make
mips
misc-devices drivers/misc/isl29003.c: driver for the ISL29003 ambient light sensor 2009-04-01 08:59:18 -07:00
mn10300 trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
mtd trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
namespaces
netlabel
networking Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2009-06-15 03:02:23 -07:00
parisc
PCI
pcmcia
power Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-06-14 13:46:25 -07:00
powerpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-06-15 09:40:05 -07:00
prctl
RCU trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
s390 trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
scheduler trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2009-06-17 09:50:44 -07:00
serial
sh
sound Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-06-14 13:46:25 -07:00
sparc
spi spi: documentation: emphasise spi_master.setup() semantics 2009-04-21 13:41:50 -07:00
sysctl vmscan: properly account for the number of page cache pages zone_reclaim() can reclaim 2009-06-16 19:47:45 -07:00
telephony
thermal
timers trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
trace debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
uml
usb trivial: usb: fix missing space typo in doc 2009-06-12 18:01:51 +02:00
video4linux V4L/DVB (11996): saa7134: add support for AVerMedia M103 (f736) 2009-06-16 19:07:53 -03:00
vm Documentation/vm/Makefile: don't try to build slqbinfo 2009-06-17 09:45:46 -07:00
w1
watchdog
wimax
x86 Merge branch 'linus' into x86/mce3 2009-06-11 23:31:52 +02:00
zh_CN
00-INDEX trivial: fix where cgroup documentation is not correctly referred to 2009-03-30 15:22:02 +02:00
applying-patches.txt
atomic_ops.txt Documentation/atomic_ops.txt: fix sample code 2009-06-16 19:47:52 -07:00
bad_memory.txt
basic_profiling.txt [PATCH] oprofile: report anonymous region samples 2005-06-24 00:06:27 -07:00
binfmt_misc.txt
braille-console.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
bt8xxgpio.txt
BUG-HUNTING
c2port.txt
cachetlb.txt
Changes Documentation/Changes: perl is needed to build the kernel 2009-06-18 13:03:46 -07:00
CodingStyle trivial: fix typo milisecond/millisecond for documentation and source comments. 2009-06-12 18:01:46 +02:00
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
credentials.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt trivial: Documentation/dell_rbu.txt: fix typos 2009-06-12 18:01:50 +02:00
devices.txt lanana: assign a device name and numbering for MAX3100 2009-04-07 08:44:05 -07:00
DMA-API.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
DMA-attributes.txt
DMA-ISA-LPC.txt
DMA-mapping.txt dma-mapping: update the old macro DMA_nBIT_MASK related documentations 2009-04-07 08:31:12 -07:00
dmaengine.txt
dontdiff dontdiff: Fix asm exclude 2009-03-26 15:45:43 -07:00
dynamic-debug-howto.txt Dynamic debug: allow simple quoting of words 2009-03-24 16:38:27 -07:00
edac.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
eisa.txt
email-clients.txt
exception.txt
feature-removal-schedule.txt irqs: add IRQF_SAMPLE_RANDOM to the feature-removal-schedule.txt (deprecated) list 2009-06-18 13:03:40 -07:00
futex-requeue-pi.txt futex: add requeue-pi documentation 2009-05-09 07:12:50 +02:00
gcov.txt gcov: add gcov profiling infrastructure 2009-06-18 13:03:57 -07:00
gpio.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
highuid.txt
HOWTO
hw_random.txt
ics932s401
initrd.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
IO-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt kernel-doc: restrict syntax for private: and public: 2009-05-02 15:36:10 -07:00
kernel-docs.txt
kernel-parameters.txt gcov: add gcov profiling infrastructure 2009-06-18 13:03:57 -07:00
keys-request-key.txt
keys.txt
kmemcheck.txt kmemcheck: add the kmemcheck documentation 2009-06-13 14:27:20 +02:00
kmemleak.txt kmemleak: Add documentation on the memory leak detector 2009-06-11 17:03:29 +01:00
kobject.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
kprobes.txt debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem. 2009-06-15 21:30:28 -07:00
kref.txt
ldm.txt
leds-class.txt
local_ops.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
lockdep-design.txt locking: Documentation: lockdep-design.txt, fix note of state bits 2009-04-26 18:21:24 +02:00
lockstat.txt
logo.gif Revert "linux.conf.au 2009: Tuz" 2009-04-27 12:00:27 -07:00
logo.txt Revert "linux.conf.au 2009: Tuz" 2009-04-27 12:00:27 -07:00
magic-number.txt
Makefile
ManagementStyle
markers.txt
mca.txt
md.txt Documentation/md.txt update 2009-03-31 15:18:37 +11:00
memory-barriers.txt sched: Document memory barriers implied by sleep/wake-up primitives 2009-04-29 14:15:55 +02:00
memory-hotplug.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
memory.txt
mono.txt
mutex-design.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
rbtree.txt trivial: rbtree.txt: fix rb_entry() parameters in sample code 2009-06-12 18:01:47 +02:00
rfkill.txt rfkill: document /dev/rfkill 2009-06-03 14:06:15 -04:00
robust-futex-ABI.txt futex: documentation: fix inconsistent description of futex list_op_pending 2009-06-18 13:03:56 -07:00
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
SELinux.txt
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
slow-work.txt Document the slow work thread pool 2009-04-03 16:42:35 +01:00
SM501.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
Smack.txt smack: implement logging V3 2009-04-14 09:00:23 +10:00
sparse.txt Documentation: explain the difference between __bitwise and __bitwise__ 2009-04-11 08:18:11 +02:00
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2009-06-14 13:46:25 -07:00
svga.txt
sysfs-rules.txt Doc/sysfs-rules: Swap the order of the words so the sentence makes more sense 2009-05-08 19:22:20 -07:00
sysrq.txt Merge branch 'tracing/core-v2' into tracing-for-linus 2009-04-02 00:49:02 +02:00
tomoyo.txt tomoyo: add Documentation/tomoyo.txt 2009-04-14 09:14:58 +10:00
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
video-output.txt
volatile-considered-harmful.txt
voyager.txt
zorro.txt