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linux-stable/include/linux/kconfig.h

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kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
#ifndef __LINUX_KCONFIG_H
#define __LINUX_KCONFIG_H
#include <generated/autoconf.h>
/*
kconfig: fix IS_ENABLED to not require all options to be defined Using IS_ENABLED() within C (vs. within CPP #if statements) in its current form requires us to actually define every possible bool/tristate Kconfig option twice (__enabled_* and __enabled_*_MODULE variants). This results in a huge autoconf.h file, on the order of 16k lines for a x86_64 defconfig. Fixing IS_ENABLED to be able to work on the smaller subset of just things that we really have defined is step one to fixing this. Which means it has to not choke when fed non-enabled options, such as: include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef] The original prototype of how to implement a C and preprocessor compatible way of doing this came from the Google+ user "comex ." in response to Linus' crowdsourcing challenge for a possible improvement on his earlier C specific solution: #define config_enabled(x) (__stringify(x)[0] == '1') In this implementation, I've chosen variable names that hopefully make how it works more understandable. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 23:46:32 +00:00
* Helper macros to use CONFIG_ options in C/CPP expressions. Note that
kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
* these only work with boolean and tristate options.
*/
kconfig: fix IS_ENABLED to not require all options to be defined Using IS_ENABLED() within C (vs. within CPP #if statements) in its current form requires us to actually define every possible bool/tristate Kconfig option twice (__enabled_* and __enabled_*_MODULE variants). This results in a huge autoconf.h file, on the order of 16k lines for a x86_64 defconfig. Fixing IS_ENABLED to be able to work on the smaller subset of just things that we really have defined is step one to fixing this. Which means it has to not choke when fed non-enabled options, such as: include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef] The original prototype of how to implement a C and preprocessor compatible way of doing this came from the Google+ user "comex ." in response to Linus' crowdsourcing challenge for a possible improvement on his earlier C specific solution: #define config_enabled(x) (__stringify(x)[0] == '1') In this implementation, I've chosen variable names that hopefully make how it works more understandable. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 23:46:32 +00:00
/*
* Getting something that works in C and CPP for an arg that may or may
* not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
* we match on the placeholder define, insert the "0," for arg1 and generate
* the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
* When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
* the last step cherry picks the 2nd arg, we get a zero.
*/
#define __ARG_PLACEHOLDER_1 0,
#define config_enabled(cfg) _config_enabled(cfg)
#define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
#define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0)
#define ___config_enabled(__ignored, val, ...) val
kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
/*
* IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
* otherwise. For boolean options, this is equivalent to
* IS_ENABLED(CONFIG_FOO).
*/
kconfig: fix IS_ENABLED to not require all options to be defined Using IS_ENABLED() within C (vs. within CPP #if statements) in its current form requires us to actually define every possible bool/tristate Kconfig option twice (__enabled_* and __enabled_*_MODULE variants). This results in a huge autoconf.h file, on the order of 16k lines for a x86_64 defconfig. Fixing IS_ENABLED to be able to work on the smaller subset of just things that we really have defined is step one to fixing this. Which means it has to not choke when fed non-enabled options, such as: include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef] The original prototype of how to implement a C and preprocessor compatible way of doing this came from the Google+ user "comex ." in response to Linus' crowdsourcing challenge for a possible improvement on his earlier C specific solution: #define config_enabled(x) (__stringify(x)[0] == '1') In this implementation, I've chosen variable names that hopefully make how it works more understandable. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 23:46:32 +00:00
#define IS_BUILTIN(option) config_enabled(option)
kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
/*
* IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
* otherwise.
*/
kconfig: fix IS_ENABLED to not require all options to be defined Using IS_ENABLED() within C (vs. within CPP #if statements) in its current form requires us to actually define every possible bool/tristate Kconfig option twice (__enabled_* and __enabled_*_MODULE variants). This results in a huge autoconf.h file, on the order of 16k lines for a x86_64 defconfig. Fixing IS_ENABLED to be able to work on the smaller subset of just things that we really have defined is step one to fixing this. Which means it has to not choke when fed non-enabled options, such as: include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef] The original prototype of how to implement a C and preprocessor compatible way of doing this came from the Google+ user "comex ." in response to Linus' crowdsourcing challenge for a possible improvement on his earlier C specific solution: #define config_enabled(x) (__stringify(x)[0] == '1') In this implementation, I've chosen variable names that hopefully make how it works more understandable. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-12 23:46:32 +00:00
#define IS_MODULE(option) config_enabled(option##_MODULE)
kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
[media] Add and use IS_REACHABLE macro In the media drivers, the v4l2 core knows about all submodules and calls into them from a common function. However this cannot work if the modules that get called are loadable and the core is built-in. In that case we get drivers/built-in.o: In function `set_type': drivers/media/v4l2-core/tuner-core.c:301: undefined reference to `tea5767_attach' drivers/media/v4l2-core/tuner-core.c:307: undefined reference to `tea5761_attach' drivers/media/v4l2-core/tuner-core.c:349: undefined reference to `tda9887_attach' drivers/media/v4l2-core/tuner-core.c:405: undefined reference to `xc4000_attach' This was working previously, until the IS_ENABLED() macro was used to replace the construct like #if defined(CONFIG_DVB_CX24110) || (defined(CONFIG_DVB_CX24110_MODULE) && defined(MODULE)) with the difference that the new code no longer checks whether it is being built as a loadable module itself. To fix this, this new patch adds an 'IS_REACHABLE' macro, which evaluates true in exactly the condition that was used previously. The downside of this is that this trades an obvious link error for a more subtle runtime failure, but it is clear that the change that introduced the link error was unintentional and it seems better to revert it for now. Also, a similar change was originally created by Trent Piepho and then reverted by teh change to the IS_ENABLED macro. Ideally Kconfig would be used to avoid the case of a broken dependency, or the code restructured in a way to turn around the dependency, but either way would require much larger changes here. Fixes: 7b34be71db53 ("[media] use IS_ENABLED() macro") See-also: c5dec9fb248e ("V4L/DVB (4751): Fix DBV_FE_CUSTOMISE for card drivers compiled into kernel") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-02-18 17:12:42 +00:00
/*
* IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
* code can call a function defined in code compiled based on CONFIG_FOO.
* This is similar to IS_ENABLED(), but returns false when invoked from
* built-in code when CONFIG_FOO is set to 'm'.
*/
#define IS_REACHABLE(option) (config_enabled(option) || \
(config_enabled(option##_MODULE) && config_enabled(MODULE)))
include/linux/kconfig.h: ese macros which are already defined It is better to use macros which are already available because then there is just one location which needs to be change. [akpm@linux-foundation.org: move IS_ENABLED definition to after the IS_BUILTIN and IS_MODULE definitions] Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-16 19:48:38 +00:00
/*
* IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
* 0 otherwise.
*/
#define IS_ENABLED(option) \
(IS_BUILTIN(option) || IS_MODULE(option))
kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE() Replace the config_is_*() macros with a variant that allows for grepping for usage of CONFIG_* options in the code. Usage: if (IS_ENABLED(CONFIG_NUMA)) or #if IS_ENABLED(CONFIG_NUMA) The IS_ENABLED() macro evaluates to 1 if the argument is set (to either 'y' or 'm'), IS_BUILTIN() tests if the option is 'y' and IS_MODULE() test if the option is 'm'. Only boolean and tristate options are supported. Reviewed-by: Arnaud Lacombe <lacombar@gmail.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-07-20 15:38:57 +00:00
#endif /* __LINUX_KCONFIG_H */