| Message ID | 1362656642-2693-1-git-send-email-james.hogan@imgtec.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
James Hogan <james.hogan@imgtec.com> writes: > The commit "consolidate cond_syscall and SYSCALL_ALIAS declarations" > broke the build on blackfin and metag due to the following code: > > #ifndef SYMBOL_NAME > #ifdef CONFIG_SYMBOL_PREFIX > #define SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX ## x > #else > #define SYMBOL_NAME(x) x > #endif > #endif > #define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x)) > > __stringify literally stringifies CONFIG_SYMBOL_PREFIX ##x, so you get > lines like this in the assembly output: > > .weak CONFIG_SYMBOL_PREFIXsys_quotactl > .set > CONFIG_SYMBOL_PREFIXsys_quotactl,CONFIG_SYMBOL_PREFIXsys_ni_syscall > > This is fixed by defining SYMBOL_PREFIX from the command line for c > files in addition to assembly for architectures that set > CONFIG_SYMBOL_PREFIX (scripts/Makefile.lib), and defining __SYMBOL_NAME > as: > > #define __SYMBOL_NAME(x) __stringify(SYMBOL_PREFIX) #x > > We first have to ensure SYMBOL_PREFIX is defined (which avoids polluting > the command lines for architectures that don't use symbol prefixes). > Also the definition of SYMBOL_PREFIX in <linux/kernel.h> is removed as > it conflicts, isn't used anywhere, and is defined as a string so differs > from the assembly definition. So now, if CONFIG_SYMBOL_PREFIX, SYMBOL_PREFIX is defined on the cmdline as a string. Otherwise it's empty (not the empty string?): > +/* This helps us to avoid #ifdef SYMBOL_PREFIX */ > +#ifndef SYMBOL_PREFIX > +#define SYMBOL_PREFIX > #endif > -#define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x)) > + > +#define __SYMBOL_NAME(x) __stringify(SYMBOL_PREFIX) #x And why are you __stringify()ing a string? > #ifndef cond_syscall > #define cond_syscall(x) asm(".weak\t" __SYMBOL_NAME(x) \ > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index 07125e6..f1cce6a 100644 > --- a/scripts/Makefile.lib > +++ b/scripts/Makefile.lib > @@ -123,6 +123,7 @@ ifdef CONFIG_SYMBOL_PREFIX > _sym_flags = -DSYMBOL_PREFIX=$(patsubst "%",%,$(CONFIG_SYMBOL_PREFIX)) > _cpp_flags += $(_sym_flags) > _a_flags += $(_sym_flags) > +_c_flags += $(_sym_flags) > endif Confused, Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Rusty, On 08/03/13 00:03, Rusty Russell wrote: > James Hogan <james.hogan@imgtec.com> writes: >> Also the definition of SYMBOL_PREFIX in <linux/kernel.h> is removed as >> it conflicts, isn't used anywhere, and is defined as a string so differs >> from the assembly definition. > > So now, if CONFIG_SYMBOL_PREFIX, SYMBOL_PREFIX is defined on the cmdline > as a string. Otherwise it's empty (not the empty string?): No, SYMBOL_PREFIX is now defined as a non-string, same as asm files, but the now unused definition in linux/kernel.h did define it as a string as it used CONFIG_SYMBOL_PREFIX which is a string. When I said "and is defined as a string" I was referring to the one in linux/kernel.h that this removes. Does that make sense? It's all a bit messy unfortunately (hence RFC). Cheers James -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 80d3687..e13e992 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -723,13 +723,6 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } /* Trap pasters of __FUNCTION__ at compile-time */ #define __FUNCTION__ (__func__) -/* This helps us to avoid #ifdef CONFIG_SYMBOL_PREFIX */ -#ifdef CONFIG_SYMBOL_PREFIX -#define SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX -#else -#define SYMBOL_PREFIX "" -#endif - /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ #ifdef CONFIG_FTRACE_MCOUNT_RECORD # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD diff --git a/include/linux/linkage.h b/include/linux/linkage.h index 829d66c..acb869b 100644 --- a/include/linux/linkage.h +++ b/include/linux/linkage.h @@ -15,14 +15,12 @@ #define asmlinkage CPP_ASMLINKAGE #endif -#ifndef SYMBOL_NAME -#ifdef CONFIG_SYMBOL_PREFIX -#define SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX ## x -#else -#define SYMBOL_NAME(x) x -#endif +/* This helps us to avoid #ifdef SYMBOL_PREFIX */ +#ifndef SYMBOL_PREFIX +#define SYMBOL_PREFIX #endif -#define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x)) + +#define __SYMBOL_NAME(x) __stringify(SYMBOL_PREFIX) #x #ifndef cond_syscall #define cond_syscall(x) asm(".weak\t" __SYMBOL_NAME(x) \ diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 07125e6..f1cce6a 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -123,6 +123,7 @@ ifdef CONFIG_SYMBOL_PREFIX _sym_flags = -DSYMBOL_PREFIX=$(patsubst "%",%,$(CONFIG_SYMBOL_PREFIX)) _cpp_flags += $(_sym_flags) _a_flags += $(_sym_flags) +_c_flags += $(_sym_flags) endif
The commit "consolidate cond_syscall and SYSCALL_ALIAS declarations" broke the build on blackfin and metag due to the following code: #ifndef SYMBOL_NAME #ifdef CONFIG_SYMBOL_PREFIX #define SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX ## x #else #define SYMBOL_NAME(x) x #endif #endif #define __SYMBOL_NAME(x) __stringify(SYMBOL_NAME(x)) __stringify literally stringifies CONFIG_SYMBOL_PREFIX ##x, so you get lines like this in the assembly output: .weak CONFIG_SYMBOL_PREFIXsys_quotactl .set CONFIG_SYMBOL_PREFIXsys_quotactl,CONFIG_SYMBOL_PREFIXsys_ni_syscall This is fixed by defining SYMBOL_PREFIX from the command line for c files in addition to assembly for architectures that set CONFIG_SYMBOL_PREFIX (scripts/Makefile.lib), and defining __SYMBOL_NAME as: #define __SYMBOL_NAME(x) __stringify(SYMBOL_PREFIX) #x We first have to ensure SYMBOL_PREFIX is defined (which avoids polluting the command lines for architectures that don't use symbol prefixes). Also the definition of SYMBOL_PREFIX in <linux/kernel.h> is removed as it conflicts, isn't used anywhere, and is defined as a string so differs from the assembly definition. Signed-off-by: James Hogan <james.hogan@imgtec.com> --- This is just one possible way of fixing it. It felt the cleanest out of the ways I tried, but feel free to suggest something better! include/linux/kernel.h | 7 ------- include/linux/linkage.h | 12 +++++------- scripts/Makefile.lib | 1 + 3 files changed, 6 insertions(+), 14 deletions(-)