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authorAlexander Duyck <alexander.h.duyck@redhat.com>2014-12-11 15:01:55 -0800
committerDavid S. Miller <davem@davemloft.net>2014-12-11 21:15:05 -0500
commit8a449718414ff10b9d5559ed3e8e09c7178774f2 (patch)
tree81097c0d6949fb90e40176ddff1f4be30467b576 /arch/x86/um
parentc11a9009ae6a8c42a8cd69d885601e1aa6fbea04 (diff)
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arch: Cleanup read_barrier_depends() and comments
This patch is meant to cleanup the handling of read_barrier_depends and smp_read_barrier_depends. In multiple spots in the kernel headers read_barrier_depends is defined as "do {} while (0)", however we then go into the SMP vs non-SMP sections and have the SMP version reference read_barrier_depends, and the non-SMP define it as yet another empty do/while. With this commit I went through and cleaned out the duplicate definitions and reduced the number of definitions down to 2 per header. In addition I moved the 50 line comments for the macro from the x86 and mips headers that defined it as an empty do/while to those that were actually defining the macro, alpha and blackfin. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/x86/um')
-rw-r--r--arch/x86/um/asm/barrier.h7
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/x86/um/asm/barrier.h b/arch/x86/um/asm/barrier.h
index cc04e67bfd05..d6511d954e2b 100644
--- a/arch/x86/um/asm/barrier.h
+++ b/arch/x86/um/asm/barrier.h
@@ -29,8 +29,6 @@
#endif /* CONFIG_X86_32 */
-#define read_barrier_depends() do { } while (0)
-
#ifdef CONFIG_SMP
#define smp_mb() mb()
@@ -42,7 +40,6 @@
#define smp_wmb() barrier()
-#define smp_read_barrier_depends() read_barrier_depends()
#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
#else /* CONFIG_SMP */
@@ -50,11 +47,13 @@
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
-#define smp_read_barrier_depends() do { } while (0)
#define set_mb(var, value) do { var = value; barrier(); } while (0)
#endif /* CONFIG_SMP */
+#define read_barrier_depends() do { } while (0)
+#define smp_read_barrier_depends() do { } while (0)
+
/*
* Stop RDTSC speculation. This is needed when you need to use RDTSC
* (or get_cycles or vread that possibly accesses the TSC) in a defined