diff options
| author | Will Deacon <will.deacon@arm.com> | 2017-10-24 11:22:46 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-10-24 13:17:32 +0200 |
| commit | d15155824c5014803d91b829736d249c500bdda6 (patch) | |
| tree | 5d71b9e3e5811a7804a6aa5d139fe5beee4d2ce8 /arch/um | |
| parent | 9babb091e0ec84f7503fde0a2d9a2a16a0f48e3c (diff) | |
linux/compiler.h: Split into compiler.h and compiler_types.h
linux/compiler.h is included indirectly by linux/types.h via
uapi/linux/types.h -> uapi/linux/posix_types.h -> linux/stddef.h
-> uapi/linux/stddef.h and is needed to provide a proper definition of
offsetof.
Unfortunately, compiler.h requires a definition of
smp_read_barrier_depends() for defining lockless_dereference() and soon
for defining READ_ONCE(), which means that all
users of READ_ONCE() will need to include asm/barrier.h to avoid splats
such as:
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from arch/h8300/kernel/asm-offsets.c:11:
include/linux/list.h: In function 'list_empty':
>> include/linux/compiler.h:343:2: error: implicit declaration of function 'smp_read_barrier_depends' [-Werror=implicit-function-declaration]
smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \
^
A better alternative is to include asm/barrier.h in linux/compiler.h,
but this requires a type definition for "bool" on some architectures
(e.g. x86), which is defined later by linux/types.h. Type "bool" is also
used directly in linux/compiler.h, so the whole thing is pretty fragile.
This patch splits compiler.h in two: compiler_types.h contains type
annotations, definitions and the compiler-specific parts, whereas
compiler.h #includes compiler-types.h and additionally defines macros
such as {READ,WRITE.ACCESS}_ONCE().
uapi/linux/stddef.h and linux/linkage.h are then moved over to include
linux/compiler_types.h, which fixes the build for h8 and blackfin.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/include/shared/init.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/um/include/shared/init.h b/arch/um/include/shared/init.h index 233e2593eee0..094e96ce653b 100644 --- a/arch/um/include/shared/init.h +++ b/arch/um/include/shared/init.h @@ -40,7 +40,7 @@ typedef int (*initcall_t)(void); typedef void (*exitcall_t)(void); -#include <linux/compiler.h> +#include <linux/compiler_types.h> /* These are for everybody (although not all archs will actually discard it in modules) */ |