[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <lsq.1396221815.842109211@decadent.org.uk>
Date: Mon, 31 Mar 2014 00:23:35 +0100
From: Ben Hutchings <ben@...adent.org.uk>
To: linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC: akpm@...ux-foundation.org, "Len Brown" <len.brown@...el.com>,
"Josh Triplett" <josh@...htriplett.org>
Subject: [PATCH 3.2 045/200] turbostat: Use GCC's CPUID functions to
support PIC
3.2.56-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Josh Triplett <josh@...htriplett.org>
commit 2b92865e648ce04a39fda4f903784a5d01ecb0dc upstream.
turbostat uses inline assembly to call cpuid. On 32-bit x86, on systems
that have certain security features enabled by default that make -fPIC
the default, this causes a build error:
turbostat.c: In function ‘check_cpuid’:
turbostat.c:1906:2: error: PIC register clobbered by ‘ebx’ in ‘asm’
asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx");
^
GCC provides a header cpuid.h, containing a __get_cpuid function that
works with both PIC and non-PIC. (On PIC, it saves and restores ebx
around the cpuid instruction.) Use that instead.
Signed-off-by: Josh Triplett <josh@...htriplett.org>
Signed-off-by: Len Brown <len.brown@...el.com>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
tools/power/x86/turbostat/turbostat.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -32,6 +32,7 @@
#include <dirent.h>
#include <string.h>
#include <ctype.h>
+#include <cpuid.h>
#define MSR_TSC 0x10
#define MSR_NEHALEM_PLATFORM_INFO 0xCE
@@ -847,7 +848,7 @@ void check_cpuid()
eax = ebx = ecx = edx = 0;
- asm("cpuid" : "=a" (max_level), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (0));
+ __get_cpuid(0, &max_level, &ebx, &ecx, &edx);
if (ebx == 0x756e6547 && edx == 0x49656e69 && ecx == 0x6c65746e)
genuine_intel = 1;
@@ -856,7 +857,7 @@ void check_cpuid()
fprintf(stderr, "%.4s%.4s%.4s ",
(char *)&ebx, (char *)&edx, (char *)&ecx);
- asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx");
+ __get_cpuid(1, &fms, &ebx, &ecx, &edx);
family = (fms >> 8) & 0xf;
model = (fms >> 4) & 0xf;
stepping = fms & 0xf;
@@ -878,7 +879,7 @@ void check_cpuid()
* This check is valid for both Intel and AMD.
*/
ebx = ecx = edx = 0;
- asm("cpuid" : "=a" (max_level), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (0x80000000));
+ __get_cpuid(0x80000000, &max_level, &ebx, &ecx, &edx);
if (max_level < 0x80000007) {
fprintf(stderr, "CPUID: no invariant TSC (max_level 0x%x)\n", max_level);
@@ -889,7 +890,7 @@ void check_cpuid()
* Non-Stop TSC is advertised by CPUID.EAX=0x80000007: EDX.bit8
* this check is valid for both Intel and AMD
*/
- asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (0x80000007));
+ __get_cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
has_invariant_tsc = edx & (1 << 8);
if (!has_invariant_tsc) {
@@ -902,7 +903,7 @@ void check_cpuid()
* this check is valid for both Intel and AMD
*/
- asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (0x6));
+ __get_cpuid(0x6, &eax, &ebx, &ecx, &edx);
has_aperf = ecx & (1 << 0);
if (!has_aperf) {
fprintf(stderr, "No APERF MSR\n");
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists