Commit Graph

41 Commits

Author SHA1 Message Date
Petr Vorel
1ccb271433 kconfig: make "Selected by:" and "Implied by:" readable
Reverse dependency expressions can get rather unwieldy, especially if
a symbol is selected by more than a handful of other symbols. I.e. it's
possible to have near endless expressions like:
   A && B && !C || D || F && (G || H) || [...]

Chop these expressions into actually readable chunks:
   - A && B && !C
   - D
   - F && (G || H)
   - [...]

I.e. transform the top level OR tokens into newlines and prepend each
line with a minus. This makes the "Selected by:" and "Implied by:" blurb
much easier to read. This is done only if there is more than one top
level OR. "Depends on:" and "Range :" were deliberately left as they are.

Based on idea from Paul Bolle.

Suggested-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-25 21:53:00 +09:00
Ulf Magnusson
52aede4ba5 kconfig: Document the 'symbol' struct
Visibility and choices in particular might be a bit tricky to figure
out.

Also fix existing comment to point out that P_MENU is also used for
menus.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-07 23:46:57 +09:00
Ulf Magnusson
33ca1a2486 kconfig: Document the 'menu' struct
Understanding what it represents helps a lot when reading the code, and
it's not obvious, so document it.

The ROOT_MENU flag is only set and tested by the gconf and qconf front
ends, so leave it undocumented here. The obvious guess for what it means
is correct.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-07 23:46:16 +09:00
Nicolas Pitre
237e3ad0f1 Kconfig: Introduce the "imply" keyword
The "imply" keyword is a weak version of "select" where the target
config symbol can still be turned off, avoiding those pitfalls that come
with the "select" keyword.

This is useful e.g. with multiple drivers that want to indicate their
ability to hook into a secondary subsystem while allowing the user to
configure that subsystem out without also having to unset these drivers.

Currently, the same effect can almost be achieved with:

config DRIVER_A
	tristate

config DRIVER_B
	tristate

config DRIVER_C
	tristate

config DRIVER_D
	tristate

[...]

config SUBSYSTEM_X
	tristate
	default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...]

This is unwieldy to maintain especially with a large number of drivers.
Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X
to y or n, excluding m, when some drivers are built-in. The "select"
keyword allows for excluding m, but it excludes n as well. Hence
this "imply" keyword.  The above becomes:

config DRIVER_A
	tristate
	imply SUBSYSTEM_X

config DRIVER_B
	tristate
	imply SUBSYSTEM_X

[...]

config SUBSYSTEM_X
	tristate

This is much cleaner, and way more flexible than "select". SUBSYSTEM_X
can still be configured out, and it can be set as a module when none of
the drivers are configured in or all of them are modular.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:33 +01:00
Jan Beulich
31847b67be kconfig: allow use of relations other than (in)equality
Over the years I found it desirable to be able to use all sorts of
relations, not just (in)equality. And apparently I'm not the only one,
as there's at least one example in the tree where the programmer
assumed this would work (see DEBUG_UART_8250_WORD in
arch/arm/Kconfig.debug). Another possible use would e.g. be to fold the
two SMP/NR_CPUS prompts into one: SMP could be promptless, simply
depending on NR_CPUS > 1.

A (desirable) side effect of this change - resulting from numeric
values now necessarily being compared as numbers rather than as
strings - is that comparing hex values now works as expected: Other
than int ones (which aren't allowed to have leading zeroes), zeroes
following the 0x prefix made them compare unequal even if their values
were equal.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-06-15 14:05:58 +02:00
Michal Marek
ad8d40cda3 kconfig: Remove unnecessary prototypes from headers
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-02-25 15:00:17 +01:00
Josh Triplett
5d2acfc7b9 kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT
"make allnoconfig" exists to ease testing of minimal configurations.
Documentation/SubmitChecklist includes a note to test with allnoconfig.
This helps catch missing dependencies on common-but-not-required
functionality, which might otherwise go unnoticed.

However, allnoconfig still leaves many symbols enabled, because they're
hidden behind CONFIG_EMBEDDED or CONFIG_EXPERT.  For instance, allnoconfig
still has CONFIG_PRINTK and CONFIG_BLOCK enabled, so drivers don't
typically get build-tested with those disabled.

To address this, introduce a new Kconfig option "allnoconfig_y", used on
symbols which only exist to hide other symbols.  Set it on CONFIG_EMBEDDED
(which then selects CONFIG_EXPERT).  allnoconfig will then disable all the
symbols hidden behind those.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:09 -07:00
Martin Walch
31bfb10820 kconfig: add short explanation to SYMBOL_WRITE
replace the question mark in the comment after SYMBOL_WRITE with an explanation

Signed-off-by: Martin Walch <walch.martin@web.de>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
2013-10-08 23:52:14 +02:00
Arve Hjønnevåg
fbe98bb9ed kconfig: Fix defconfig when one choice menu selects options that another choice menu depends on
The defconfig and Kconfig combination below, which is based on 3.10-rc4
Kconfigs, resulted in several options getting set to "m" instead of "y".

defconfig.choice:
---8<---
CONFIG_MODULES=y
CONFIG_USB_ZERO=y
---8<---

Kconfig.choice:
---8<---
menuconfig MODULES
	bool "Enable loadable module support"

config CONFIGFS_FS
	tristate "Userspace-driven configuration filesystem"

config OCFS2_FS
        tristate "OCFS2 file system support"
        depends on CONFIGFS_FS
        select CRC32

config USB_LIBCOMPOSITE
	tristate
	select CONFIGFS_FS

choice
	tristate "USB Gadget Drivers"
	default USB_ETH

config USB_ZERO
	tristate "Gadget Zero (DEVELOPMENT)"
	select USB_LIBCOMPOSITE

config USB_ETH
	tristate "Ethernet Gadget (with CDC Ethernet support)"
	select USB_LIBCOMPOSITE

endchoice

config CRC32
        tristate "CRC32/CRC32c functions"
        default y

choice
        prompt "CRC32 implementation"
        depends on CRC32
        default CRC32_SLICEBY8

config CRC32_SLICEBY8
        bool "Slice by 8 bytes"

endchoice
---8<---

$ scripts/kconfig/conf --defconfig=defconfig.choice Kconfig.choice

would result in:

.config:
---8<---
CONFIG_MODULES=y
CONFIG_CONFIGFS_FS=m
CONFIG_USB_LIBCOMPOSITE=m
CONFIG_USB_ZERO=m
CONFIG_CRC32=y
CONFIG_CRC32_SLICEBY8=y
---8<---

when the expected result would be:

.config:
---8<---
CONFIG_MODULES=y
CONFIG_CONFIGFS_FS=y
CONFIG_USB_LIBCOMPOSITE=y
CONFIG_USB_ZERO=y
CONFIG_CRC32=y
CONFIG_CRC32_SLICEBY8=y
---8<---

Signed-off-by: Arve Hjønnevåg <arve@android.com>
[yann.morin.1998@free.fr: add the resulting .config to commit log,
                          remove unneeded USB_GADGET from the defconfig]
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
2013-06-16 11:00:30 +02:00
Benjamin Poirier
bad9955db1 menuconfig: Replace CIRCLEQ by list_head-style lists.
sys/queue.h and CIRCLEQ in particular have proven to cause portability
problems (reported on Debian Sarge, Cygwin and FreeBSD)

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Yaakov Selkowitz <yselkowitz@users.sourceforge.net>
Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-10-25 15:06:00 +02:00
Benjamin Poirier
95ac9b3b58 menuconfig: Assign jump keys per-page instead of globally
At the moment, keys 1-9 are assigned to the first 9 search results. This patch
makes them assigned to the first 9 results per-page instead. We are much less
likely to run out of keys that way.

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-09-27 18:09:24 +02:00
Benjamin Poirier
5e609addb1 menuconfig: Add jump keys to search results
makes it possible to jump directly to the menu for a configuration entry after
having searched for it with '/'. If this menu is not currently accessible we
jump to the nearest accessible parent instead. After exiting this menu, the
user is returned to the search results where he may jump further in or
elsewhere.

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-09-27 18:09:24 +02:00
Arnaud Lacombe
37ae2d5998 kbuild: Fix compiler warning with assertion when calling 'fwrite'
Reinhard Tartler discovered a corner case of calling xfwrite() where the
length of the string is zero.

Arnaud Lacombe suggested to use assertion for the corner case, as
fwrite(3) is currently used:

 1) in comment printers. Empty comment are not allowed.
 2) in a callback passed to expr_print(), where the string printed is
    either NULL OR non-empty.
 3) in the lexer, auto-generated, and unused.

I feel using assertion is a good solution:

 1) It cleanly takes care of the above-mentioned corner case.
 2) It can be easily disabled by defining NDEBUG.
 3) It asserts xfwrite() is simply a wrapper for fwrite().

Reported-by: Reinhard Tartler <Reinhard.Tartler@informatik.uni-erlangen.de>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-01-15 00:17:18 +01:00
Arnaud Lacombe
84250386ef kconfig: nuke reference to SWIG
SWIG is not used (yet?) to create kconfig binding, so there is no point
referencing it.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-06 15:32:18 -04:00
Yann E. MORIN
2b2112f617 kconfig: get rid of unused flags
Now that we detect recusrion of sourced files, get rid of
now unused flags.

Regenerate lex.zconf.c_shipped file.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-04-15 15:12:57 +02:00
Linus Torvalds
f28b1c8aaa Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  nconf: handle comment entries within choice/endchoice
  kconfig: fix warning
  kconfig: Make expr_copy() take a const argument
  kconfig: simplify select-with-unmet-direct-dependency warning
  kconfig: add more S_INT and S_HEX consistency checks
  kconfig: fix `zconfdebug' extern declaration
  kconfig/conf: merge duplicate switch's case
  kconfig: fix typos
  kbuild/gconf: add dummy inline for bind_textdomain_codeset()
  kbuild/nconf: fix spaces damage
  kconfig: nuke second argument of conf_write_symbol()
  kconfig: do not define AUTOCONF_INCLUDED
  kconfig: the day kconfig warns about "select"-abuse has come
2011-01-10 08:28:17 -08:00
Arnaud Lacombe
0597fcd08b kconfig: fix warning
In file included from scripts/kconfig/zconf.tab.c:2502:
scripts/kconfig/expr.c:1033: warning: no previous prototype for 'expr_simplify_unmet_dep'

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-27 21:46:47 +01:00
Michal Marek
17742dc743 kconfig: Make expr_copy() take a const argument
Fixes
scripts/kconfig/expr.c: In function ‘expr_get_leftmost_symbol’:
scripts/kconfig/expr.c:1026:2: warning: passing argument 1 of ‘expr_copy’ discards qualifiers from pointer target type
scripts/kconfig/expr.c:67:14: note: expected ‘struct expr *’ but argument is of type ‘const struct expr *’

Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-12-21 17:59:16 +01:00
Arnaud Lacombe
86e187ff9b kconfig: add an option to determine a menu's visibility
This option is aimed to add the possibility to control a menu's visibility
without adding dependency to the expression to all the submenu.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-11-22 11:27:17 -02:00
Michal Marek
239060b93b Merge branch 'kbuild/rc-fixes' into kbuild/kconfig
We need to revert the temporary hack in 71ebc01, hence the merge.
2010-10-12 15:09:06 +02:00
Arnaud Lacombe
ff5ff6060b kconfig: delay symbol direct dependency initialization
This fixes the use-after-free and associated crash in kconfig introduced
in commit 246cf9c26b.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-10-04 15:13:13 +02:00
Arnaud Lacombe
2e7a091833 kconfig: constify file name
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Michal Marek <mmarek@suse.cz>
2010-09-19 22:54:00 -04:00
Sam Ravnborg
59e89e3ddf kconfig: save location of config symbols
When we add a new config symbol save the file/line
so we later can refer to their location.

The information is saved as a property to a config symbol
because we may have multiple definitions of the same symbol.

This has the side-effect that a symbol always has
at least one property.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-03 13:49:31 +02:00
Catalin Marinas
246cf9c26b kbuild: Warn on selecting symbols with unmet direct dependencies
The "select" statement in Kconfig files allows the enabling of options
even if they have unmet direct dependencies (i.e. "depends on" expands
to "no"). Currently, the "depends on" clauses are used in calculating
the visibility but they do not affect the reverse dependencies in any
way.

The patch introduces additional tracking of the "depends on" statements
and prints a warning on selecting an option if its direct dependencies
are not met.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-07-02 14:53:09 +02:00
Andi Kleen
e66f25d7d1 Improve kconfig symbol hashing
While looking for something else I noticed that the symbol
hash function used by kconfig is quite poor. It doesn't
use any of the standard hash techniques but simply
adds up the string and then uses power of two masking,
which is both known to perform poorly.

The current x86 kconfig has over 7000 symbols.

When I instrumented it showed that the minimum hash chain
length was 16 and a significant number of them was over
30.

It didn't help that the hash table size was only 256 buckets.

This patch increases the hash table size to a larger prime
and switches to a FNV32 hash. I played around with a couple of hash
functions, but that one seemed to perform best with reasonable
hash table sizes.

Increasing the hash table size even further didn't
seem like a good idea, because there are a couple of global
walks which walk the complete hash table.

I also moved the unnamed bucket to 0. It's still the longest
of all the buckets (44 entries), but hopefully it's not
often hit except for the global walk which doesn't care.

The result is a much nicer distribution:
(first column bucket length, second number of buckets with that length)

1: 3505
2: 1236
3: 294
4: 52
5: 3
47: 1		<--- this is the unnamed symbols bucket

There are still some 5+ buckets, but increasing the hash table
even more would be likely not worth it.

This also cleans up the code slightly by removing hard coded
magic numbers.

I didn't notice a big performance difference either way
on my Nehalem system, but I presume it'll help somewhat
on slower systems.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-02-02 14:33:55 +01:00
Sam Ravnborg
cf82607a90 kconfig: struct property commented
No functional changes

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-01-02 20:43:21 +01:00
Sam Ravnborg
5b2cf365a8 kconfig: add comments to symbol flags
No functional changes - only comments.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-01-02 20:43:21 +01:00
Sam Ravnborg
eaa2a87460 kconfig: explain symbol value defaults
Added a few comments - no functional change.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-01-02 20:43:20 +01:00
Roman Zippel
93449082e9 kconfig: environment symbol support
Add the possibility to import a value from the environment into kconfig
via the option syntax. Beside flexibility this has the advantage
providing proper dependencies.
Documented the options syntax.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:14:39 +01:00
Roman Zippel
7a96292335 kconfig: explicitly introduce expression list
Rename E_CHOICE to E_LIST to explicitly add support for expression
lists. Add a helper macro expr_list_for_each_sym to more easily iterate
over the list.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:14:39 +01:00
Sam Ravnborg
de83cf148a kconfig: delete unused FILE_ and SYMBOL_ flags
The *_PRINTED flags were never used - so delete them.
Do we need them later then we can re-add them.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
2008-01-28 23:14:38 +01:00
Sam Ravnborg
d6ee35764f kconfig: rename E_OR & friends to avoid name clash
We had macros named the same as a set of enumeration values.
It is legal code but very confusing to read - so rename
the macros from E_* to EXPR_*

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
2008-01-28 23:14:38 +01:00
Sam Ravnborg
1edf1c00ac kconfig: remove unused members from struct symbol
dep and dep2 in struct symbol was unused - remove them.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
2007-07-25 21:14:30 +02:00
Sam Ravnborg
03d2912273 kconfig: attach help text to menus
Roman Zippel wrote:
> A simple example would be
> help texts, right now they are per symbol, but they should really be per
> menu, so archs can provide different help texts for something.

This patch does this and at the same time introduce a few API
funtions used to access the help text.

The relevant api functions are introduced in the various frontends.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
2007-07-25 21:14:26 +02:00
Roman Zippel
face4374e2 kconfig: add defconfig_list/module option
This makes it possible to change two options which were hardcoded sofar.
1. Any symbol can now take the role of CONFIG_MODULES
2. The more useful option is to change the list of default file names,
   which kconfig uses to load the base configuration if .config isn't
   available.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Roman Zippel
2e3646e51b kconfig: integrate split config into silentoldconfig
Now that kconfig can load multiple configurations, it becomes simple to
integrate the split config step, by simply comparing the new .config file with
the old auto.conf (and then saving the new auto.conf).  A nice side effect is
that this saves a bit of disk space and cache, as no data needs to be read
from or saved into the splitted config files anymore (e.g.  include/config is
now 648KB instead of 5.2MB).

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Roman Zippel
669bfad906 kconfig: allow loading multiple configurations
Extend conf_read_simple() so it can load multiple configurations.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Roman Zippel
0c1822e699 kconfig: allow multiple default values per symbol
Extend struct symbol to allow storing multiple default values, which can be
used to hold multiple configurations.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Roman Zippel
c0e150acde kconfig: remove SYMBOL_{YES,MOD,NO}
The SYMBOL_{YES,MOD,NO} are not really used anymore (they were more used be
the cml1 converter), so just remove them.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
David Gibson
3f04e7ddf4 [PATCH] kconfig: Fix Kconfig performance bug
When doing its recursive dependency check, scripts/kconfig/conf uses the flag
SYMBOL_CHECK_DONE to avoid rechecking a symbol it has already checked.
However, that flag is only set at the top level, so if a symbol is first
encountered as a dependency of another symbol it will be rechecked every time
it is encountered until it's encountered at the top level.

This patch adjusts the flag setting so that each symbol will only be checked
once, regardless of whether it is first encountered at the top level, or while
recursing down from another symbol.  On complex configurations, this vastly
speeds up scripts/kconfig/conf.  The config in the powerpc merge tree is
particularly bad: this patch reduces the time for 'scripts/kconfig/conf -o
arch/powerpc/Kconfig' by a factor of 40 on a G5.  That's even including the
time to print the config, so the speedup in the actual checking is more likely
2 or 3 orders of magnitude.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:53 -08:00
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