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* [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686
@ 2013-02-14 19:35 Benson Leung
  2013-02-14 19:35 ` Benson Leung
  2013-02-19 20:18 ` [PATCH v4 0/1] " Benson Leung
  0 siblings, 2 replies; 6+ messages in thread
From: Benson Leung @ 2013-02-14 19:35 UTC (permalink / raw)
  To: len.brown, colin.king, linux-kernel; +Cc: bleung, vapier

Hi Len,

Please take a look at this patch to the x86_energy_perf_policy that allows
the tool to work when built for i686 with PIC enabled.

Thanks,
Benson


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686
  2013-02-14 19:35 [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686 Benson Leung
@ 2013-02-14 19:35 ` Benson Leung
  2013-02-18  5:06   ` Len Brown
  2013-02-18  5:17   ` Mike Frysinger
  2013-02-19 20:18 ` [PATCH v4 0/1] " Benson Leung
  1 sibling, 2 replies; 6+ messages in thread
From: Benson Leung @ 2013-02-14 19:35 UTC (permalink / raw)
  To: len.brown, colin.king, linux-kernel; +Cc: bleung, vapier

x86_energy_perf_policy reads cpuid using the cpuid instruction.
On i686, when building with PIC, this clobbers ebx, the PIC register.

Fixed using the same cpuid accessor function that vapier@gentoo.org
created for i7z:
http://code.google.com/p/i7z/issues/detail?id=31

Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
v3 : No changes.
v2 : make cpuid static inline. Remove unused eax from validate_cpuid and
clean up return variables from cpuid().
---
 .../x86_energy_perf_policy.c                       | 30 +++++++++++++++++-----
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
index 40b3e54..f8f4e63 100644
--- a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
+++ b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
@@ -130,20 +130,36 @@ void cmdline(int argc, char **argv)
 	}
 }
 
+static inline void cpuid(unsigned int info, unsigned int *eax,
+			 unsigned int *ebx, unsigned int *ecx,
+			 unsigned int *edx)
+{
+	unsigned int _eax = info, _ebx, _ecx, _edx;
+	asm volatile ("mov %%ebx, %%edi;" /* save ebx (for PIC) */
+		      "cpuid;"
+		      "mov %%ebx, %%esi;" /* pass to caller */
+		      "mov %%edi, %%ebx;" /* restore ebx */
+		      :"+a" (_eax), "=S" (_ebx), "=c" (_ecx), "=d" (_edx)
+		      :      /* inputs: eax is handled above */
+		      :"edi" /* clobbers: we hit edi directly */);
+	if (eax) *eax = _eax;
+	if (ebx) *ebx = _ebx;
+	if (ecx) *ecx = _ecx;
+	if (edx) *edx = _edx;
+}
+
 /*
  * validate_cpuid()
  * returns on success, quietly exits on failure (make verbose with -v)
  */
 void validate_cpuid(void)
 {
-	unsigned int eax, ebx, ecx, edx, max_level;
+	unsigned int ebx, ecx, edx, max_level;
 	unsigned int fms, family, model, stepping;
 
-	eax = ebx = ecx = edx = 0;
-
-	asm("cpuid" : "=a" (max_level), "=b" (ebx), "=c" (ecx),
-		"=d" (edx) : "a" (0));
+	ebx = ecx = edx = 0;
 
+	cpuid(0, &max_level, &ebx, &ecx, &edx);
 	if (ebx != 0x756e6547 || edx != 0x49656e69 || ecx != 0x6c65746e) {
 		if (verbose)
 			fprintf(stderr, "%.4s%.4s%.4s != GenuineIntel",
@@ -151,7 +167,7 @@ void validate_cpuid(void)
 		exit(1);
 	}
 
-	asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx");
+	cpuid(1, &fms, NULL, NULL, &edx);
 	family = (fms >> 8) & 0xf;
 	model = (fms >> 4) & 0xf;
 	stepping = fms & 0xf;
@@ -173,7 +189,7 @@ void validate_cpuid(void)
 	 * Support for MSR_IA32_ENERGY_PERF_BIAS
 	 * is indicated by CPUID.06H.ECX.bit3
 	 */
-	asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (6));
+	cpuid(6, NULL, NULL, &ecx, NULL);
 	if (verbose)
 		printf("CPUID.06H.ECX: 0x%x\n", ecx);
 	if (!(ecx & (1 << 3))) {
-- 
1.8.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686
  2013-02-14 19:35 ` Benson Leung
@ 2013-02-18  5:06   ` Len Brown
  2013-02-18  5:17   ` Mike Frysinger
  1 sibling, 0 replies; 6+ messages in thread
From: Len Brown @ 2013-02-18  5:06 UTC (permalink / raw)
  To: Benson Leung; +Cc: colin.king, linux-kernel, vapier

Hi Benson,

checkpatch.pl doesn't love this syntax:

ERROR: spaces required around that ':' (ctx:ExV)
#113: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:142:
+		      :"+a" (_eax), "=S" (_ebx), "=c" (_ecx), "=d" (_edx)
 		      ^

ERROR: spaces required around that ':' (ctx:ExV)
#115: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:144:
+		      :"edi" /* clobbers: we hit edi directly */);
 		      ^

ERROR: trailing statements should be on next line
#116: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:145:
+	if (eax) *eax = _eax;

ERROR: trailing statements should be on next line
#117: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:146:
+	if (ebx) *ebx = _ebx;

ERROR: trailing statements should be on next line
#118: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:147:
+	if (ecx) *ecx = _ecx;

ERROR: trailing statements should be on next line
#119: FILE: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c:148:
+	if (edx) *edx = _edx;

total: 6 errors, 2 warnings, 57 lines checked

/home/lenb/Documents/epp.eml has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
Commit Body is:
--------------------------
tools/power x86_energy_perf_policy: fix cpuid for i686


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686
  2013-02-14 19:35 ` Benson Leung
  2013-02-18  5:06   ` Len Brown
@ 2013-02-18  5:17   ` Mike Frysinger
  1 sibling, 0 replies; 6+ messages in thread
From: Mike Frysinger @ 2013-02-18  5:17 UTC (permalink / raw)
  To: Benson Leung; +Cc: len.brown, colin.king, linux-kernel

[-- Attachment #1: Type: Text/Plain, Size: 532 bytes --]

On Thursday 14 February 2013 14:35:58 Benson Leung wrote:
> +	asm volatile ("mov %%ebx, %%edi;" /* save ebx (for PIC) */
> +		      "cpuid;"
> +		      "mov %%ebx, %%esi;" /* pass to caller */
> +		      "mov %%edi, %%ebx;" /* restore ebx */
> +		      :"+a" (_eax), "=S" (_ebx), "=c" (_ecx), "=d" (_edx)
> +		      :      /* inputs: eax is handled above */
> +		      :"edi" /* clobbers: we hit edi directly */);

i've written a better version since:
https://github.com/linux-test-project/ltp/blob/master/include/ltp_cpuid.h
-mike

[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v4 0/1] tools/power x86_energy_perf_policy: fix cpuid for i686
  2013-02-14 19:35 [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686 Benson Leung
  2013-02-14 19:35 ` Benson Leung
@ 2013-02-19 20:18 ` Benson Leung
  2013-02-19 20:18   ` [PATCH v4 1/1] " Benson Leung
  1 sibling, 1 reply; 6+ messages in thread
From: Benson Leung @ 2013-02-19 20:18 UTC (permalink / raw)
  To: len.brown, colin.king, linux-kernel; +Cc: bleung, vapier

Thanks Len and Mike for your comments. I've fixed the style problems so this
is now checkpatch clean.

I've also moved to Mike's better cpuid from ltp.

Thanks,
Benson


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v4 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686
  2013-02-19 20:18 ` [PATCH v4 0/1] " Benson Leung
@ 2013-02-19 20:18   ` Benson Leung
  0 siblings, 0 replies; 6+ messages in thread
From: Benson Leung @ 2013-02-19 20:18 UTC (permalink / raw)
  To: len.brown, colin.king, linux-kernel; +Cc: bleung, vapier

x86_energy_perf_policy reads cpuid using the cpuid instruction.
On i686, when building with PIC, this clobbers ebx, the PIC register.

Fixed using the cpuid accessor function that vapier@gentoo.org wrote:
https://raw.github.com/linux-test-project/ltp/master/include/ltp_cpuid.h

Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
v4 : Cleaned up checkpatch.pl style errors. Used vapier's newer better cpuid.
v3 : No changes.
v2 : make cpuid static inline. Remove unused eax from validate_cpuid and
clean up return variables from cpuid().
---
 .../x86_energy_perf_policy.c                       | 42 ++++++++++++++++++----
 1 file changed, 35 insertions(+), 7 deletions(-)

diff --git a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
index 40b3e54..4372bd2 100644
--- a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
+++ b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
@@ -130,20 +130,48 @@ void cmdline(int argc, char **argv)
 	}
 }
 
+static inline void cpuid(unsigned int info, unsigned int *eax,
+			 unsigned int *ebx, unsigned int *ecx,
+			 unsigned int *edx)
+{
+#if defined(__i386__) || defined(__x86_64__)
+	unsigned int _eax = info, _ebx, _ecx, _edx;
+	asm volatile (
+# ifdef __i386__
+		      "xchg %%ebx, %%esi;" /* save ebx (for PIC) */
+		      "cpuid;"
+		      "xchg %%esi, %%ebx;" /* restore ebx & pass to caller */
+		      : "=S" (_ebx),
+#else
+		      "cpuid;"
+		      : "=b" (_ebx),
+#endif
+			"+a" (_eax), "=c" (_ecx), "=d" (_edx)
+		      : /* inputs: eax is handled above */
+	);
+	if (eax)
+		*eax = _eax;
+	if (ebx)
+		*ebx = _ebx;
+	if (ecx)
+		*ecx = _ecx;
+	if (edx)
+		*edx = _edx;
+#endif
+}
+
 /*
  * validate_cpuid()
  * returns on success, quietly exits on failure (make verbose with -v)
  */
 void validate_cpuid(void)
 {
-	unsigned int eax, ebx, ecx, edx, max_level;
+	unsigned int ebx, ecx, edx, max_level;
 	unsigned int fms, family, model, stepping;
 
-	eax = ebx = ecx = edx = 0;
-
-	asm("cpuid" : "=a" (max_level), "=b" (ebx), "=c" (ecx),
-		"=d" (edx) : "a" (0));
+	ebx = ecx = edx = 0;
 
+	cpuid(0, &max_level, &ebx, &ecx, &edx);
 	if (ebx != 0x756e6547 || edx != 0x49656e69 || ecx != 0x6c65746e) {
 		if (verbose)
 			fprintf(stderr, "%.4s%.4s%.4s != GenuineIntel",
@@ -151,7 +179,7 @@ void validate_cpuid(void)
 		exit(1);
 	}
 
-	asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx");
+	cpuid(1, &fms, NULL, NULL, &edx);
 	family = (fms >> 8) & 0xf;
 	model = (fms >> 4) & 0xf;
 	stepping = fms & 0xf;
@@ -173,7 +201,7 @@ void validate_cpuid(void)
 	 * Support for MSR_IA32_ENERGY_PERF_BIAS
 	 * is indicated by CPUID.06H.ECX.bit3
 	 */
-	asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (6));
+	cpuid(6, NULL, NULL, &ecx, NULL);
 	if (verbose)
 		printf("CPUID.06H.ECX: 0x%x\n", ecx);
 	if (!(ecx & (1 << 3))) {
-- 
1.8.1.3


^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-02-19 20:18 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-02-14 19:35 [PATCH v3 1/1] tools/power x86_energy_perf_policy: fix cpuid for i686 Benson Leung
2013-02-14 19:35 ` Benson Leung
2013-02-18  5:06   ` Len Brown
2013-02-18  5:17   ` Mike Frysinger
2013-02-19 20:18 ` [PATCH v4 0/1] " Benson Leung
2013-02-19 20:18   ` [PATCH v4 1/1] " Benson Leung

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