When DYNAMIC_FTRACE is enabled and we use the C version of recordmcount,
all objects are run through the recordmcount program to create a
separate section that stores all the callers of mcount.
The build process has a special file: scripts/mod/empty.o. This is
built from empty.c which is literally an empty file (except for a
single comment). This file is used to find information about the target
elf format, like endianness and word size.
The problem comes up when we need to build recordmcount. The
build process requires that empty.o is built first. The build rules
for empty.o will try to execute recordmcount on the empty.o file.
We get an error that recordmcount does not exist.
To avoid this recursion, the build file will skip running recordmcount
if the file that it is building is script/mod/empty.o.
[ extra comment Suggested-by: Sam Ravnborg <sam@ravnborg.org> ]
Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Ingo Molnar <mingo@elte.hu>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The C version of recordmcount is compiled to a binary, which will
end up located in the objtree. If the kernel is built with O=path,
the srctree will not include the binary recordmcount caller.
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The file kernel/trace/ftrace.c references the mcount() call to
convert the mcount() callers to nops. But because it references
mcount(), the mcount() address is placed in the relocation table.
The C version of recordmcount reads the relocation table of all
object files, and it will add all references to mcount to the
__mcount_loc table that is used to find the places that call mcount()
and change the call to a nop. When recordmcount finds the mcount reference
in kernel/trace/ftrace.o, it saves that location even though the code
is not a call, but references mcount as data.
On boot up, when all calls are converted to nops, the code has a safety
check to determine what op code it is actually replacing before it
replaces it. If that op code at the address does not match, then
a warning is printed and the function tracer is disabled.
The reference to mcount in ftrace.c, causes this warning to trigger,
since the reference is not a call to mcount(). The ftrace.c file is
not compiled with the -pg flag, so no calls to mcount() should be
expected.
This patch simply makes recordmcount.c skip the kernel/trace/ftrace.c
file. This was the same solution used by the perl version of
recordmcount.
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The elf reader for recordmcount.c had duplicate functions for both
32 bit and 64 bit elf handling. This was due to the need of using
the 32 and 64 bit elf structures.
This patch consolidates the two by using macros to define the 32
and 64 bit names in a recordmcount.h file, and then by just defining
a RECORD_MCOUNT_64 macro and including recordmcount.h twice we
create the funtions for both the 32 bit version as well as the
64 bit version using one code source.
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch adds the support for the C version of recordmcount and
compile times show ~ 12% improvement.
After verifying this works, other archs can add:
HAVE_C_MCOUNT_RECORD
in its Kconfig and it will use the C version of recordmcount
instead of the perl version.
Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently, the mcount callers are found with a perl script that does
an objdump on every file in the kernel. This is a C version of that
same code which should increase the performance time of compiling
the kernel with dynamic ftrace enabled.
Signed-off-by: John Reiser <jreiser@bitwagon.com>
[ Updated the code to include .text.unlikely section as well as
changing the format to follow Linux coding style. ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The following build bug occurs on distcc builds:
CC arch/x86/kernel/asm-offsets.s
In file included from include/linux/module.h:24,
from include/linux/crypto.h:22,
from arch/x86/kernel/asm-offsets_64.c:9,
from arch/x86/kernel/asm-offsets.c:5:
include/trace/events/module.h: In function 'trace_module_load':
include/trace/events/module.h:18: error: expected '(' before 'goto'
include/trace/events/module.h:18: error: expected identifier or '*' before '(' token
It triggers because distcc is invoked by turning $CC into "distcc gcc",
but gcc-goto.sh check script was using $1 not $@ to expand parameters.
Cc: Jason Baron <jbaron@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100923034910.867858597@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <ee8b3595967989fdaf84e698dc7447d315ce972a.1284733808.git.jbaron@redhat.com>
[ cleaned up some formating ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When you don't use !E or !I but only !F, then it's very easy to miss
including some functions, structs etc. in documentation. To help
finding which ones were missed, allow printing out the unused ones as
warnings.
For example, using this on mac80211 yields a lot of warnings like this:
Warning: didn't use docs for DOC: mac80211 workqueue
Warning: didn't use docs for ieee80211_max_queues
Warning: didn't use docs for ieee80211_bss_change
Warning: didn't use docs for ieee80211_bss_conf
when generating the documentation for it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are valid attributes that could have upper case letters, but we
still want to remove, like for example
__attribute__((aligned(NETDEV_ALIGN)))
as encountered in the wireless code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
setlocalversion: Ignote SCMs above the linux source tree
makefile: not need to regenerate kernel.release file when make kernelrelease
fixes for using make 3.82
kconfig: fix segfault when detecting recursive dependency
kconfig: fix savedefconfig with choice marked optional
Dan McGee <dpmcgee@gmail.com> writes:
> Note that when in git, you get the appended "+" sign. If
> LOCALVERSION_AUTO is set, you will get something like
> "eee-gb01b08c-dirty" (whereas the copy of the tree in /tmp still
> returns "eee"). It doesn't matter whether the working tree is dirty or
> clean.
>
> Is there a way to disable this? I'm building from a clean tarball that
> just happens to be unpacked inside a git repository. One would think
> setting LOCALVERSION_AUTO to false would do it, but no such luck...
Fix this by checking if the kernel source tree is the root of the git or
hg repository. No fix for svn: If the kernel source is not tracked in
the svn repository, it works as expected, otherwise determining the
'repository root' is not really a defined task.
Reported-and-tested-by: Dan McGee <dpmcgee@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
It doesn't like pattern and explicit rules to be on the same line,
and it seems to be more picky when matching file (or really directory)
names with different numbers of trailing slashes.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Andrew Benton <b3nton@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Following sample Kconfig generated a segfault:
config FOO
bool
select PERF_EVENTS if HAVE_HW_BREAKPOINT
config PERF_EVENTS
bool
config HAVE_HW_BREAKPOINT
bool
depends on PERF_EVENTS
Fix by reverting back to a valid property if there was no
property on the stack of symbols.
The above pattern were seen in sh Kconfig.
A fix for the Kconfig file has been sent to the sh folks.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
savedefconfig failed to save the correct minimal config
when it encountered a choice marked optional.
Consider following minimal configuration:
$cat Kconfig
choice
prompt "choice"
optional
config A
bool "a"
config B
bool "b"
endchoice
$cat .config | grep -v ^#
CONFIG_A=y
$conf --savedefconfig=defconfig Kconfig
would before this fix result in an empty file, because
kconfig would assume that CONFIG_A=y is a default value.
But because the choice is optional the default is that
both A and B are =n.
Fix so we handle optional choices correct.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
setlocalversion: fix version for untaged nontip mercurial revs
Fix CONFIG_CROSS_COMPILE issue in .config
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
kconfig: Fix warning: ignoring return value of 'fgets'
kconfig: Fix warning: ignoring return value of 'fwrite'
nconfig: Fix segfault when menu is empty
kconfig: fix tristate choice with minimal config
kconfig: fix savedefconfig for tristate choices
The manpage for cut says it will return all lines without the delimiter
unless -s is specified.
When I backed up my mecurial tree to generate modules, I found that the
scm part of localversion was turning up blank.
Signed-off-by: Milton Miller <miltonm@bga.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: "Michał Górny" <gentoo@mgorny.alt.pl>
Signed-off-by: Michal Marek <mmarek@suse.cz>
This fix facilitates fgets() either it returns on success or on error or
when end of file occurs.
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
This fix facilitates fwrite() in both confdata.c and expr.c, either it
succeeds in writing, or an error occurs, or the end of file is reached.
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
nconf crush with segfault if press right arrow in empty menu.
Signed-off-by: Andrej Gelenberg <andrej.gelenberg@udo.edu>
Signed-off-by: Michal Marek <mmarek@suse.cz>
