asm/rwonce: Don't pull <asm/barrier.h> into 'asm-generic/rwonce.h'

Now that 'smp_read_barrier_depends()' has gone the way of the Norwegian
Blue, drop the inclusion of <asm/barrier.h> in 'asm-generic/rwonce.h'.

This requires fixups to some architecture vdso headers which were
previously relying on 'asm/barrier.h' coming in via 'linux/compiler.h'.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will@kernel.org>

arch/arm/include/asm/vdso/gettimeofday.h

@@ -7,6 +7,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/barrier.h>
 #include <asm/errno.h>
 #include <asm/unistd.h>
 #include <asm/vdso/cp15.h>

arch/arm64/include/asm/vdso/compat_gettimeofday.h

@@ -7,6 +7,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/barrier.h>
 #include <asm/unistd.h>
 #include <asm/errno.h>
 

arch/arm64/include/asm/vdso/gettimeofday.h

@@ -7,6 +7,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/barrier.h>
 #include <asm/unistd.h>
 
 #define VDSO_HAS_CLOCK_GETRES		1

arch/riscv/include/asm/vdso/gettimeofday.h

@@ -4,6 +4,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/barrier.h>
 #include <asm/unistd.h>
 #include <asm/csr.h>
 #include <uapi/linux/time.h>

include/asm-generic/rwonce.h

@@ -26,8 +26,6 @@
 #include <linux/kasan-checks.h>
 #include <linux/kcsan-checks.h>
 
-#include <asm/barrier.h>
-
 /*
  * Yes, this permits 64-bit accesses on 32-bit architectures. These will
  * actually be atomic in some cases (namely Armv7 + LPAE), but for others we

include/linux/nospec.h

@@ -5,6 +5,8 @@
 
 #ifndef _LINUX_NOSPEC_H
 #define _LINUX_NOSPEC_H
+
+#include <linux/compiler.h>
 #include <asm/barrier.h>
 
 struct task_struct;