Commit Graph

46 Commits

Author SHA1 Message Date
Gustavo A. R. Silva
859c817501 modpost,fixdep: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
3f9070a67a fixdep: remove redundant null character check
If *q is '\0', the condition (isalnum(*q) || *q == '_') is false anyway.

It is redundant to ensure non-zero *q.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-02 21:18:19 +09:00
Masahiro Yamada
87d660f085 fixdep: remove unneeded code and comments about *.ver files
This is probably stale code. In old days (~ Linux 2.5.59), Kbuild made
genksyms generate include/linux/modules/*.ver files.

The currenct Kbuild does not generate *.ver files at all.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-02 21:18:19 +09:00
Masahiro Yamada
6f9ac9f442 fixdep: check return value of printf() and putchar()
When there is not enough space on your storage device, the build will
fail with 'No space left on device' error message.

The reason is obvious from the message, so you will free up some disk
space, then you will resume the build.

However, sometimes you may still see a mysterious error message:

  unterminated call to function 'wildcard': missing ')'.

If you run out of the disk space, fixdep may end up with generating
incomplete .*.cmd files.

For example, if the disk-full error occurs while fixdep is running
print_dep(), the .*.cmd might be truncated like this:

   $(wildcard include/config/

When you run 'make' next time, this broken .*.cmd will be included,
then Make will terminate parsing since it is a wrong syntax.

Once this happens, you need to run 'make clean' or delete the broken
.*.cmd file manually.

Even if you do not see any error message, the .*.cmd files after any
error could be potentially incomplete, and unreliable. You may miss
the re-compilation due to missing header dependency.

If printf() cannot output the string for disk shortage or whatever
reason, it returns a negative value, but currently fixdep does not
check it at all. Consequently, fixdep *successfully* generates a
broken .*.cmd file. Make never notices that since fixdep exits with 0,
which means success.

Given the intended usage of fixdep, it must respect the return value
of not only malloc(), but also printf() and putchar().

This seems a long-standing issue since the introduction of fixdep.

In old days, Kbuild tried to provide an extra safety by letting fixdep
output to a temporary file and renaming it after everything is done:

  scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\
  rm -f $(depfile);                                                    \
  mv -f $(dot-target).tmp $(dot-target).cmd)

It was no help to avoid the current issue; fixdep successfully created
a truncated tmp file, which would be renamed to a .*.cmd file.

This problem should be fixed by propagating the error status to the
build system because:

[1] Since commit 9c2af1c737 ("kbuild: add .DELETE_ON_ERROR special
    target"), Make will delete the target automatically on any failure
    in the recipe.

[2] Since commit 392885ee82 ("kbuild: let fixdep directly write to
    .*.cmd files"), .*.cmd file is included only when the corresponding
    target already exists.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-07-01 10:30:39 +09:00
Masahiro Yamada
bbda5ec671 kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS
My main motivation of this commit is to clean up scripts/Kbuild.include
and scripts/Makefile.build.

Currently, CONFIG_TRIM_UNUSED_KSYMS works with a tricky gimmick;
possibly exported symbols are detected by letting $(CPP) replace
EXPORT_SYMBOL* with a special string '=== __KSYM_*===', which is
post-processed by sed, and passed to fixdep. The extra preprocessing
is costly, and hacking cmd_and_fixdep is ugly.

I came up with a new way to find exported symbols; insert a dummy
symbol __ksym_marker_* to each potentially exported symbol. Those
dummy symbols are picked up by $(NM), post-processed by sed, then
appended to .*.cmd files. I collected the post-process part to a
new shell script scripts/gen_ksymdeps.sh for readability. The dummy
symbols are put into the .discard.* section so that the linker
script rips them off the final vmlinux or modules.

A nice side-effect is building with CONFIG_TRIM_UNUSED_KSYMS will
be much faster.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
2018-12-01 23:13:14 +09:00
Nicolas Pitre
b3aa58d2e8 fixdep: suppress consecutive / from file paths in dependency list files
Underscores in symbol names are translated into slashes for path names.
Filesystems treat consecutive slashes as if there was only one, so
let's do the same in the dependency list for easier grepping, etc.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-07 21:40:39 +09:00
Masahiro Yamada
fbfa9be990 kbuild: move include/config/ksym/* to include/ksym/*
The idea of using fixdep was inspired by Kconfig, but autoksyms
belongs to a different group.  So, I want to move those touched
files under include/config/ksym/ to include/ksym/.

The directory include/ksym/ can be removed by 'make clean' because
it is meaningless for the external module building.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
2018-03-26 02:01:23 +09:00
Rasmus Villemoes
638e69cf22 fixdep: do not ignore kconfig.h
kconfig.h was excluded from consideration by fixdep by
6a5be57f0f (fixdep: fix extraneous dependencies) to avoid some false
positive hits

(1) include/config/.h
(2) include/config/h.h
(3) include/config/foo.h

(1) occurred because kconfig.h contains the string CONFIG_ in a
comment. However, since dee81e9886 (fixdep: faster CONFIG_ search), we
have a check that the part after CONFIG_ is non-empty, so this does not
happen anymore (and CONFIG_ appears by itself elsewhere, so that check
is worthwhile).

(2) comes from the include guard, __LINUX_KCONFIG_H. But with the
previous patch, we no longer match that either.

That leaves (3), which amounts to one [1] false dependency (aka stat() call
done by make), which I think we can live with:

We've already had one case [2] where the lack of include/linux/kconfig.h in
the .o.cmd file caused a missing rebuild, and while I originally thought
we should just put kconfig.h in the dependency list without parsing it
for the CONFIG_ pattern, we actually do have some real CONFIG_ symbols
mentioned in it, and one can imagine some translation unit that just
does '#ifdef __BIG_ENDIAN' but doesn't through some other header
actually depend on CONFIG_CPU_BIG_ENDIAN - so changing the target
endianness could end up rebuilding the world, minus that small
TU. Quoting Linus,

  ... when missing dependencies cause a missed re-compile, the resulting
  bugs can be _really_ subtle.

[1] well, two, we now also have CONFIG_BOOGER/booger.h - we could change
that to FOO if we care

[2] https://lkml.org/lkml/2018/2/22/838

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-05 23:48:29 +09:00
Rasmus Villemoes
5b8ad96d1a fixdep: remove some false CONFIG_ matches
The string CONFIG_ quite often appears after other alphanumerics,
meaning that that instance cannot be referencing a Kconfig
symbol. Omitting these means make has fewer files to stat() when
deciding what needs to be rebuilt - for a defconfig build, this seems to
remove about 2% of the (wildcard ...) lines from the .o.cmd files.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-05 23:48:25 +09:00
Rasmus Villemoes
14a596a7e6 fixdep: remove stale references to uml-config.h
uml-config.h hasn't existed in this decade (87e299e5c7 - x86, um: get
rid of uml-config.h). The few remaining UML_CONFIG instances are defined
directly in terms of their real CONFIG symbol in common-offsets.h, so
unlike when the symbols got defined via a sed script, anything that uses
UML_CONFIG_FOO now should also automatically pick up a dependency on
CONFIG_FOO via the normal fixdep mechanism (since common-offsets.h
should at least recursively be a dependency). Hence I believe we should
actually be able to ignore the HELLO_CONFIG_BOOM cases.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Richard Weinberger <richard@nod.at>
Cc: user-mode-linux-devel@lists.sourceforge.net
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-05 23:48:21 +09:00
Masahiro Yamada
ab9ce9feed fixdep: use existing helper to check modular CONFIG options
str_ends_with() tests if the given token ends with a particular string.
Currently, it is used to check file paths without $(srctree).

Actually, we have one more place where this helper is useful.  Use it
to check if CONFIG option ends with _MODULE.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:39 +09:00
Masahiro Yamada
87b95a8135 fixdep: refactor parse_dep_file()
parse_dep_file() has too much indentation, and puts the code far to
the right.  This commit refactors the code and reduces the one level
of indentation.

strrcmp() computes 'slen' by itself, but the caller already knows the
length of the token, so 'slen' can be passed via function argument.
With this, we can swap the order of strrcmp() and "*p = \0;"

Also, strrcmp() is an ambiguous function name.  Flip the logic and
rename it to str_ends_with().

I added a new helper is_ignored_file() - this returns 1 if the token
represents a file that should be ignored.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:39 +09:00
Masahiro Yamada
5d1ef76f5a fixdep: move global variables to local variables of main()
I do not mind global variables where they are useful enough.  In this
case, I do not see a good reason to use global variables since they
are just referenced in shallow places.  It is easy to pass them via
function arguments.

I squashed print_cmdline() into main() since it is just one line code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:38 +09:00
Masahiro Yamada
ccfe78873c fixdep: remove unneeded memcpy() in parse_dep_file()
Each token in the depfile is copied to the temporary buffer 's' to
terminate the token with zero.  We do not need to do this any more
because the parsed buffer is now writable.  Insert '\0' directly in
the buffer without calling memcpy().

<limits.h> is no longer necessary. (It was needed for PATH_MAX).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:38 +09:00
Masahiro Yamada
4003fd80cb fixdep: factor out common code for reading files
Now, do_config_files() and print_deps() are almost the same.  Only
the difference is the parser function called (parse_config_file vs
parse_dep_file).

We can reduce the code duplication by factoring out the common code
into read_file() - this function allocates a buffer and loads a file
to it.  It returns the pointer to the allocated buffer.  (As before,
it bails out by exit(2) for any error.)  The caller must free the
buffer when done.

Having empty source files is possible; fixdep should simply skip them.
I deleted the "st.st_size == 0" check, so read_file() allocates 1-byte
buffer for an empty file.  strstr() will immediately return NULL, and
this is what we expect.

On the other hand, an empty dep_file should be treated as an error.
In this case, parse_dep_file() will error out with "no targets found"
and it is a correct error message.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:38 +09:00
Masahiro Yamada
01b5cbe701 fixdep: use malloc() and read() to load dep_file to buffer
Commit dee81e9886 ("fixdep: faster CONFIG_ search") changed how to
read files in which CONFIG options are searched.  It used malloc()
and read() instead of mmap() because it needed to zero-terminate the
buffer in order to use strstr().  print_deps() was left untouched
since there was no reason to change it.

Now, I have two motivations to change it in the same way.

 - do_config_file() and print_deps() do quite similar things; they
   open a file, load it onto memory, and pass it to a parser function.
   If we use malloc() and read() for print_deps() too, we can factor
   out the common code.  (I will do this in the next commit.)

 - parse_dep_file() copies each token to a temporary buffer because
   it needs to zero-terminate it to be passed to printf().  It is not
   possible to modify the buffer directly because it is mmap'ed with
   O_RDONLY.  If we load the file content into a malloc'ed buffer, we
   can insert '\0' after each token, and save memcpy().  (I will do
   this in the commit after next.)

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:37 +09:00
Masahiro Yamada
41f92cffba fixdep: remove unnecessary <arpa/inet.h> inclusion
<arpa/inet.h> was included for ntohl(), but it was removed by
commit dee81e9886 ("fixdep: faster CONFIG_ search").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-18 09:37:37 +09:00
Lukas Bulwahn
7c2ec43a21 fixdep: exit with error code in error branches of do_config_file()
do_config_file() should exit with an error code on internal run-time
errors, and not return if it fails as then the error in do_config_file()
would go unnoticed in the current code and allow the build to continue.
The exit with error code will make the build fail in those very
exceptional cases. If this occurs, this actually indicates a deeper
problem in the execution of the kernel build process.

Now, in these error cases, we do not explicitly free memory and close
the file handlers in do_config_file(), as this is covered by exit().

This issue in the fixdep script was introduced with its initial
implementation back in 2002 by the original author Kai Germaschewski with
this commit 04bd72170653 ("kbuild: Make dependencies at compile time")
in the linux history git tree, i.e.,
git://git.kernel.org/pub/scm/linux/kernel/git/history/history.git.

This issue was identified during the review of a previous patch that
intended to address a memory leak detected by a static analysis tool.

Link: https://lkml.org/lkml/2017/12/14/736

Suggested-by: Nicholas Mc Guire <der.herr@hofr.at>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-08 23:51:26 +09:00
Cao jin
4e433fc4d1 fixdep: trivial: typo fix and correction
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-08-10 01:01:03 +09:00
Alexey Dobriyan
dee81e9886 fixdep: faster CONFIG_ search
Do you think kernel build is 100% dominated by gcc? You are wrong!
One small utility called "fixdep" consistently manages to sneak into
profile's first page (unless you have small monitor of course).

The choke point is this clever code:

	for (; m < end; m++) {
		if (*m == INT_CONF) { p = (char *) m  ; goto conf; }
		if (*m == INT_ONFI) { p = (char *) m-1; goto conf; }
		if (*m == INT_NFIG) { p = (char *) m-2; goto conf; }
		if (*m == INT_FIG_) { p = (char *) m-3; goto conf; }

4 branches per 4 characters is not fast.

Use strstr(3), so that SSE2 etc can be used.

With this patch, fixdep is so deep at the bottom, it is hard to find it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-08-24 22:34:19 +02:00
Nicolas Pitre
c1a95fda2a kbuild: add fine grained build dependencies for exported symbols
Like with kconfig options, we now have the ability to compile in and
out individual EXPORT_SYMBOL() declarations based on the content of
include/generated/autoksyms.h.  However we don't want the entire
world to be rebuilt whenever that file is touched.

Let's apply the same build dependency trick used for CONFIG_* symbols
where the time stamp of empty files whose paths matching those symbols
is used to trigger fine grained rebuilds. In our case the key is the
symbol name passed to EXPORT_SYMBOL().

However, unlike config options, we cannot just use fixdep to parse
the source code for EXPORT_SYMBOL(ksym) because several variants exist
and parsing them all in a separate tool, and keeping it in synch, is
not trivially maintainable.  Furthermore, there are variants such as

	EXPORT_SYMBOL_GPL(pci_user_read_config_##size);

that are instanciated via a macro for which we can't easily determine
the actual exported symbol name(s) short of actually running the
preprocessor on them.

Storing the symbol name string in a special ELF section doesn't work
for targets that output assembly or preprocessed source.

So the best way is really to leverage the preprocessor by having it
output actual symbol names anchored by a special sequence that can be
easily filtered out. Then the list of symbols is simply fed to fixdep
to be merged with the other dependencies.

That implies the preprocessor is executed twice for each source file.
A previous attempt relied on a warning pragma for each EXPORT_SYMBOL()
instance that was filtered apart from stderr by the build system with
a sed script during the actual compilation pass. Unfortunately the
preprocessor/compiler diagnostic output isn't stable between versions
and this solution, although more efficient, was deemed too fragile.

Because of the lowercasing performed by fixdep, there might be name
collisions triggering spurious rebuilds for similar symbols. But this
shouldn't be a big issue in practice. (This is the case for CONFIG_*
symbols and I didn't want to be different here, whatever the original
reason for doing so.)

To avoid needless build overhead, the exported symbol name gathering is
performed only when CONFIG_TRIM_UNUSED_KSYMS is selected.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2016-03-29 16:30:56 -04:00
Nicolas Pitre
d8329e35cc fixdep: accept extra dependencies on stdin
... and merge them in the list of parsed dependencies.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2016-03-29 16:19:40 -04:00
Tom Rini
46fe94ad18 kbuild: fixdep: Check fstat(2) return value
Coverity has recently added a check that will find when we don't check
the return code from fstat(2).  Copy/paste the checking logic that
print_deps() has with an appropriate re-wording of the perror() message.

Signed-off-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-02-17 22:52:04 +01:00
Nicolas Iooss
4c835b57b8 fixdep: constify strrcmp arguments
strrcmp only performs read access to the memory addressed by its
arguments so make them const pointers.

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-12-07 12:42:55 +01:00
Masahiro Yamada
d179e22762 kbuild: fixdep: drop meaningless hash table initialization
The clear_config() is called just once at the beginning of this
program, but the global variable hashtab[] is already zero-filled
at the start-up.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-08-24 16:36:08 +02:00
Masahiro Yamada
d721109611 kbuild: fixdep: optimize code slightly
If the target string matches "CONFIG_", move the pointer p
forward.  This saves several 7-chars adjustments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-08-24 16:36:08 +02:00
Masahiro Yamada
bb66fc6719 kbuild: trivial - use tabs for code indent where possible
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-10 14:00:53 +02:00
Stephen Warren
2ab8a99661 kbuild: fixdep: support concatenated dep files
The current use-case for fixdep is: a source file is run through a single
processing step, which creates a single dependency file as a side-effect,
which fixdep transforms into the file used by the kernel build process.

In order to transparently run the C pre-processor on device-tree files,
we wish to run both gcc -E and dtc on a source file in a single rule.
This generates two dependency files, which must be transformed together
into the file used by the kernel build process. This change modifies
fixdep so it can process the concatenation of multiple separate input
dependency files, and produce a correct unified output.

The code changes have the slight benefit of transforming the loop in
parse_dep_file() into more of a lexer/tokenizer, with the loop body being
more of a parser. Previously, some of this logic was mixed together
before the loop. I also added some comments, which I hope are useful.

Benchmarking shows that on a cross-compiled ARM tegra_defconfig build,
there is less than 0.5 seconds speed decrease with this change, on top
of a build time of ~2m24s. This is probably within the noise.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
2013-04-05 12:22:58 -06:00
Masanari Iida
8a168ca707 treewide: Fix typo in various drivers
Correct spelling typo in printk within various drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-01-09 11:43:32 +01:00
Peter Foley
6a5be57f0f fixdep: fix extraneous dependencies
The introduction of include/linux/kconfig.h created 3 extraneous
dependencies:
include/config/.h
include/config/h.h
include/config/foo.h

Fix this by excluding kconfig.h from fixdep calculations.

Signed-off-by: Peter Foley <pefoley2@verizon.net>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-09-09 11:45:47 +02:00
Michal Marek
7840fea200 kbuild: Fix computing srcversion for modules
Recent change to fixdep:

    commit b7bd182176
    Author: Michal Marek <mmarek@suse.cz>
    Date:   Thu Feb 17 15:13:54 2011 +0100

    fixdep: Do not record dependency on the source file itself

changed the format of the *.cmd files without realizing that it is also
used by modpost. Put the path to the source file to the file back, in a
special variable, so that modpost sees all source files when calculating
srcversion for modules.

Reported-and-tested-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-13 15:59:58 -07:00
Michal Marek
b7bd182176 fixdep: Do not record dependency on the source file itself
The dependency is already expressed by the Makefiles, storing it in the
.cmd file breaks build if a .c file is replaced by .S or vice versa,
because the .cmd file contains

foo/bar.o: foo/bar.c ...

foo/bar.c ... :

so the foo/bar.c -> foo/bar.o rule triggers even if there is no
foo/bar.c anymore.

Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-02-21 13:35:17 +01:00
Ben Gamari
a3ba81131a Make fixdep error handling more explicit
Also add missing error handling to fstat call

Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-22 23:23:28 +01:00
Eric Dumazet
8af27e1dc4 fixdep: use hash table instead of a single array
I noticed fixdep uses ~2% of cpu time in kernel build, in function
use_config()

fixdep spends a lot of cpu cycles in linear searches in its internal
string array. With about 400 stored strings per dep file, this begins to
be noticeable.

Convert fixdep to use a hash table.

kbuild results on my x86_64 allmodconfig

Before patch :

real	10m30.414s
user	61m51.456s
sys	8m28.200s

real	10m12.334s
user	61m50.236s
sys	8m30.448s

real	10m42.947s
user	61m50.028s
sys	8m32.380s

After:

real	10m8.180s
user	61m22.506s
sys	8m32.384s

real	10m35.039s
user	61m21.654s
sys	8m32.212s

real	10m14.487s
user	61m23.498s
sys	8m32.312s

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-11-11 17:12:06 +01:00
Sam Ravnborg
264a268380 kbuild: move autoconf.h to include/generated
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2009-12-12 13:08:15 +01:00
Linus Torvalds
c37efa9325 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (30 commits)
  Use macros for .data.page_aligned section.
  Use macros for .bss.page_aligned section.
  Use new __init_task_data macro in arch init_task.c files.
  kbuild: Don't define ALIGN and ENTRY when preprocessing linker scripts.
  arm, cris, mips, sparc, powerpc, um, xtensa: fix build with bash 4.0
  kbuild: add static to prototypes
  kbuild: fail build if recordmcount.pl fails
  kbuild: set -fconserve-stack option for gcc 4.5
  kbuild: echo the record_mcount command
  gconfig: disable "typeahead find" search in treeviews
  kbuild: fix cc1 options check to ensure we do not use -fPIC when compiling
  checkincludes.pl: add option to remove duplicates in place
  markup_oops: use modinfo to avoid confusion with underscored module names
  checkincludes.pl: provide usage helper
  checkincludes.pl: close file as soon as we're done with it
  ctags: usability fix
  kernel hacking: move STRIP_ASM_SYMS from General
  gitignore usr/initramfs_data.cpio.bz2 and usr/initramfs_data.cpio.lzma
  kbuild: Check if linker supports the -X option
  kbuild: introduce ld-option
  ...

Fix trivial conflict in scripts/basic/fixdep.c
2009-09-23 15:37:02 -07:00
Trevor Keith
f0a75770bd trivial: kbuild: remove extraneous blank line after declaration of usage()
Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:58 +02:00
Markus Heidelberg
7d3392e546 trivial: remove references to non-existent include/linux/config.h
Ignore drivers/staging/ since it is very likely that new drivers
introduce it again.

Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-09-21 15:14:52 +02:00
Trevor Keith
4356f48907 kbuild: add static to prototypes
Warnings found via gcc -Wmissing-prototypes.

Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-09-20 12:27:44 +02:00
Amerigo Wang
d067aa7415 kbuild: fix a compile warning
gcc-4.4.1:

 HOSTCC  scripts/basic/fixdep
scripts/basic/fixdep.c: In function 'traps':
scripts/basic/fixdep.c:377: warning: dereferencing type-punned pointer will break strict-aliasing rules
scripts/basic/fixdep.c:379: warning: dereferencing type-punned pointer will break strict-aliasing rules

(Apparently -fno-strict-aliasing will fix this too)

Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-06-14 22:36:23 +02:00
Andy Green
04c58f8196 kbuild: scripts/basic/fixdep segfault on pathological string-o-death
build scripts: fixdep blows segfault on string CONFIG_MODULE seen

The string "CONFIG_MODULE" appearing anywhere in a source file causes
fixdep to segfault.  This string appeared in the wild in the current
mISDN sources (I think they meant CONFIG_MODULES).  But it shouldn't
segfault (esp as CONFIG_MODULE appeared in a quoted string).

Signed-off-by: Andy Green <andy@warmcat.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-02 21:35:03 +02:00
Jan Beulich
c21b1e4d9b [PATCH] kbuild: fix dependency generation
Commit 2e3646e51b changed the way the
split config tree is built, but failed to also adjust fixdep accordingly
- if changing a config option from or to m, files referencing the
respective CONFIG_..._MODULE (but not the corresponding CONFIG_...)
didn't get rebuilt.

The problem is that trisate symbol are represent with three different
symbols:
    SYMBOL=n => no symbol defined
    SYMBOL=y => CONFIG_SYMBOL defined to '1'
    SYMBOL=m => CONFIG_SYMBOL_MODULE defined to '1'

But conf_split_config do not distingush between the =y and =m case, so
only the =y case is honoured.

This is fixed in fixdep so when a CONFIG symbol with _MODULE is found we
skip that part and only look for the CONFIG_SYMBOL version.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-01 14:23:57 -07:00
Jan Beulich
6176aa9ae4 kbuild: consolidate command line escaping
While the recent change to also escape # symbols when storing C-file
compilation command lines was helpful, it should be in effect for all
command lines, as much as the dollar escaping should be in effect for
C-source compilation commands. Additionally, for better readability and
maintenance, consolidating all the escaping (single quotes, dollars,
and now sharps) was also desirable.

Signed-Off-By: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-02-19 09:51:21 +01:00
Sam Ravnborg
4d99f93bda kbuild: escape '#' in .target.cmd files
Commandlines are contained in the .<target>.cmd files and in case they
contain a '#' char make see this as start of comment.
Teach fixdep to escape the '#' char so make will assing the full commandline.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-12-25 23:21:14 +01:00
J.A. Magallon
48b9d03c5f [PATCH] Kill signed chars
scripts/ is full of mismatches between char* params an signed char* arguments,
and viceversa.  gcc4 now complaints loud about this.  Patch below deletes all
those 'signed'.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:25:07 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00