On Tue, 22 Apr 2008 13:13:39 +0100 Will Newton wrote: > Hi, > > This patch introduces a __ARCH_WANT_SYS_SYSFS #define for > architectures that support the sysfs(2) system call. At the moment > that's everybody but blackfin, but future architectures may want to > save the (admittedly small) code size that it adds to the kernel as > well. > > (patch attached as well as inline because gmail seems to mangle my whitespace) > > --- > >From d0746366e8ccb5fbaa6c9945540cecbe0c421222 Mon Sep 17 00:00:00 2001 > From: Will Newton <will.newton@xxxxxxxxxx> > Date: Tue, 22 Apr 2008 12:57:03 +0100 > Subject: [PATCH] Introduce __ARCH_WANT_SYS_SYSFS. > > Signed-off-by: Will Newton <will.newton@xxxxxxxxxx> > > All arches that want the sysfs(2) system call should define this symbol. > Arches such as blackfin that do not implement the system call don't compile > the code and save some small amount of space. Is there any reason that this couldn't (and shouldn't) be done in the Kconfig space and done as documented in Documentation/kbuild/kconfig-language.txt ? <quote:> Adding common features and make the usage configurable ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ It is a common idiom to implement a feature/functionality that are relevant for some architectures but not all. The recommended way to do so is to use a config variable named HAVE_* that is defined in a common Kconfig file and selected by the relevant architectures. An example is the generic IOMAP functionality. We would in lib/Kconfig see: # Generic IOMAP is used to ... config HAVE_GENERIC_IOMAP config GENERIC_IOMAP depends on HAVE_GENERIC_IOMAP && FOO And in lib/Makefile we would see: obj-$(CONFIG_GENERIC_IOMAP) += iomap.o For each architecture using the generic IOMAP functionality we would see: config X86 select ... select HAVE_GENERIC_IOMAP select ... --- ~Randy -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html