[PATCH v2] perf tools: use ansi versions of asm and volatile

[PATCH v2] perf tools: use ansi versions of asm and volatile

[Ramkumar Ramachandra]

asm and volatile are provided for backward compatibility; use the ansi
versions __asm__ and __volatile__.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
---
 Thanks to Peter for pointing out the instances I missed.

 tools/perf/arch/powerpc/util/header.c |  2 +-
 tools/perf/perf.h                     | 54 +++++++++++++++++------------------
 tools/perf/tests/perf-time-to-tsc.c   |  2 +-
 tools/perf/tests/rdpmc.c              |  6 ++--
 4 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/tools/perf/arch/powerpc/util/header.c b/tools/perf/arch/powerpc/util/header.c
index 2f7073d..4b0a302 100644
--- a/tools/perf/arch/powerpc/util/header.c
+++ b/tools/perf/arch/powerpc/util/header.c
@@ -10,7 +10,7 @@
 #define __stringify(x)          __stringify_1(x)
 
 #define mfspr(rn)       ({unsigned long rval; \
-			 asm volatile("mfspr %0," __stringify(rn) \
+			 __asm__ __volatile__("mfspr %0," __stringify(rn) \
 				      : "=r" (rval)); rval; })
 
 #define SPRN_PVR        0x11F	/* Processor Version Register */
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index cf20187..6c447db 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -4,8 +4,8 @@
 #include <asm/unistd.h>
 
 #if defined(__i386__)
-#define rmb()		asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
-#define cpu_relax()	asm volatile("rep; nop" ::: "memory");
+#define rmb()		__asm__ __volatile__("lock; addl $0,0(%%esp)" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("rep; nop" ::: "memory");
 #define CPUINFO_PROC	"model name"
 #ifndef __NR_perf_event_open
 # define __NR_perf_event_open 336
@@ -13,8 +13,8 @@
 #endif
 
 #if defined(__x86_64__)
-#define rmb()		asm volatile("lfence" ::: "memory")
-#define cpu_relax()	asm volatile("rep; nop" ::: "memory");
+#define rmb()		__asm__ __volatile__("lfence" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("rep; nop" ::: "memory");
 #define CPUINFO_PROC	"model name"
 #ifndef __NR_perf_event_open
 # define __NR_perf_event_open 298
@@ -23,47 +23,47 @@
 
 #ifdef __powerpc__
 #include "../../arch/powerpc/include/uapi/asm/unistd.h"
-#define rmb()		asm volatile ("sync" ::: "memory")
-#define cpu_relax()	asm volatile ("" ::: "memory");
+#define rmb()		__asm__ __volatile__ ("sync" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__ ("" ::: "memory");
 #define CPUINFO_PROC	"cpu"
 #endif
 
 #ifdef __s390__
-#define rmb()		asm volatile("bcr 15,0" ::: "memory")
-#define cpu_relax()	asm volatile("" ::: "memory");
+#define rmb()		__asm__ __volatile__("bcr 15,0" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory");
 #endif
 
 #ifdef __sh__
 #if defined(__SH4A__) || defined(__SH5__)
-# define rmb()		asm volatile("synco" ::: "memory")
+# define rmb()		__asm__ __volatile__("synco" ::: "memory")
 #else
-# define rmb()		asm volatile("" ::: "memory")
+# define rmb()		__asm__ __volatile__("" ::: "memory")
 #endif
-#define cpu_relax()	asm volatile("" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory")
 #define CPUINFO_PROC	"cpu type"
 #endif
 
 #ifdef __hppa__
-#define rmb()		asm volatile("" ::: "memory")
-#define cpu_relax()	asm volatile("" ::: "memory");
+#define rmb()		__asm__ __volatile__("" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory");
 #define CPUINFO_PROC	"cpu"
 #endif
 
 #ifdef __sparc__
-#define rmb()		asm volatile("":::"memory")
-#define cpu_relax()	asm volatile("":::"memory")
+#define rmb()		__asm__ __volatile__("":::"memory")
+#define cpu_relax()	__asm__ __volatile__("":::"memory")
 #define CPUINFO_PROC	"cpu"
 #endif
 
 #ifdef __alpha__
-#define rmb()		asm volatile("mb" ::: "memory")
-#define cpu_relax()	asm volatile("" ::: "memory")
+#define rmb()		__asm__ __volatile__("mb" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory")
 #define CPUINFO_PROC	"cpu model"
 #endif
 
 #ifdef __ia64__
-#define rmb()		asm volatile ("mf" ::: "memory")
-#define cpu_relax()	asm volatile ("hint @pause" ::: "memory")
+#define rmb()		__asm__ __volatile__ ("mf" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__ ("hint @pause" ::: "memory")
 #define CPUINFO_PROC	"model name"
 #endif
 
@@ -73,36 +73,36 @@
  * arch/arm/kernel/entry-armv.S in the kernel source for details.
  */
 #define rmb()		((void(*)(void))0xffff0fa0)()
-#define cpu_relax()	asm volatile("":::"memory")
+#define cpu_relax()	__asm__ __volatile__("":::"memory")
 #define CPUINFO_PROC	"Processor"
 #endif
 
 #ifdef __aarch64__
-#define rmb()		asm volatile("dmb ld" ::: "memory")
-#define cpu_relax()	asm volatile("yield" ::: "memory")
+#define rmb()		__asm__ __volatile__("dmb ld" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("yield" ::: "memory")
 #endif
 
 #ifdef __mips__
-#define rmb()		asm volatile(					\
+#define rmb()		__asm__ __volatile__(					\
 				".set	mips2\n\t"			\
 				"sync\n\t"				\
 				".set	mips0"				\
 				: /* no output */			\
 				: /* no input */			\
 				: "memory")
-#define cpu_relax()	asm volatile("" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory")
 #define CPUINFO_PROC	"cpu model"
 #endif
 
 #ifdef __arc__
-#define rmb()		asm volatile("" ::: "memory")
+#define rmb()		__asm__ __volatile__("" ::: "memory")
 #define cpu_relax()	rmb()
 #define CPUINFO_PROC	"Processor"
 #endif
 
 #ifdef __metag__
-#define rmb()		asm volatile("" ::: "memory")
-#define cpu_relax()	asm volatile("" ::: "memory")
+#define rmb()		__asm__ __volatile__("" ::: "memory")
+#define cpu_relax()	__asm__ __volatile__("" ::: "memory")
 #define CPUINFO_PROC	"CPU"
 #endif
 
diff --git a/tools/perf/tests/perf-time-to-tsc.c b/tools/perf/tests/perf-time-to-tsc.c
index 0ab61b1..3fc1bc3 100644
--- a/tools/perf/tests/perf-time-to-tsc.c
+++ b/tools/perf/tests/perf-time-to-tsc.c
@@ -31,7 +31,7 @@ static u64 rdtsc(void)
 {
 	unsigned int low, high;
 
-	asm volatile("rdtsc" : "=a" (low), "=d" (high));
+	__asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high));
 
 	return low | ((u64)high) << 32;
 }
diff --git a/tools/perf/tests/rdpmc.c b/tools/perf/tests/rdpmc.c
index ff94886..3e906e1 100644
--- a/tools/perf/tests/rdpmc.c
+++ b/tools/perf/tests/rdpmc.c
@@ -9,13 +9,13 @@
 
 #if defined(__x86_64__) || defined(__i386__)
 
-#define barrier() asm volatile("" ::: "memory")
+#define barrier() __asm__ __volatile__("" ::: "memory")
 
 static u64 rdpmc(unsigned int counter)
 {
 	unsigned int low, high;
 
-	asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter));
+	__asm__ __volatile__("rdpmc" : "=a" (low), "=d" (high) : "c" (counter));
 
 	return low | ((u64)high) << 32;
 }
@@ -24,7 +24,7 @@ static u64 rdtsc(void)
 {
 	unsigned int low, high;
 
-	asm volatile("rdtsc" : "=a" (low), "=d" (high));
+	__asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high));
 
 	return low | ((u64)high) << 32;
 }
-- 
1.8.4.477.g5d89aa9

Re: [PATCH v2] perf tools: use ansi versions of asm and volatile

[Ingo Molnar]

* Ramkumar Ramachandra <artagnon@gmail.com> wrote:

> asm and volatile are provided for backward compatibility; use the ansi
> versions __asm__ and __volatile__.
> 
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
> Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
> ---
>  Thanks to Peter for pointing out the instances I missed.
> 
>  tools/perf/arch/powerpc/util/header.c |  2 +-
>  tools/perf/perf.h                     | 54 +++++++++++++++++------------------
>  tools/perf/tests/perf-time-to-tsc.c   |  2 +-
>  tools/perf/tests/rdpmc.c              |  6 ++--
>  4 files changed, 32 insertions(+), 32 deletions(-)
> 
> diff --git a/tools/perf/arch/powerpc/util/header.c b/tools/perf/arch/powerpc/util/header.c
> index 2f7073d..4b0a302 100644
> --- a/tools/perf/arch/powerpc/util/header.c
> +++ b/tools/perf/arch/powerpc/util/header.c
> @@ -10,7 +10,7 @@
>  #define __stringify(x)          __stringify_1(x)
>  
>  #define mfspr(rn)       ({unsigned long rval; \
> -			 asm volatile("mfspr %0," __stringify(rn) \
> +			 __asm__ __volatile__("mfspr %0," __stringify(rn) \

The thing is, there's a few thousand more 'nonstandard' cases in the 
kernel source:

  comet:~/tip> git grep -w 'asm.*(' | wc -l
  2617

  comet:~/tip> git grep -w '__asm__.*(' | wc -l
  2376

So unless all of them are converted I'm not convinced at all about the 
necessity of this change.

It's not like GCC will (be able to) reuse 'asm' and 'volatile' for some 
other purpose anytime soon (read: within decades, or ever), so this change 
brings not much useful to the table AFAICS.

I personally find 'asm volatile' plenty readable, the underscores don't 
add any extra info.

Thanks,

	Ingo