[PATCH] x86_64: i386/x86-64 Add nmi watchdog support for new Intel CPUs

Intel now has support for Architectural Performance Monitoring Counters
( Refer to IA-32 Intel Architecture Software Developer's Manual
http://www.intel.com/design/pentium4/manuals/253669.htm ). This
feature is present starting from Intel Core Duo and Intel Core Solo processors.

What this means is, the performance monitoring counters and some performance
monitoring events are now defined in an architectural way (using cpuid).
And there will be no need to check for family/model etc for these architectural
events.

Below is the patch to use this performance counters in nmi watchdog driver.
Patch handles both i386 and x86-64 kernels.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 20 insertions, 1 deletions

diff --git a/include/asm-x86_64/cpufeature.h b/include/asm-x86_64/cpufeature.h
index fbf5a19edbb3..ee792faaca01 100644
--- a/include/asm-x86_64/cpufeature.h
+++ b/include/asm-x86_64/cpufeature.h
@@ -67,7 +67,7 @@
 #define X86_FEATURE_SYNC_RDTSC  (3*32+6)  /* RDTSC syncs CPU core */
 #define X86_FEATURE_FXSAVE_LEAK (3*32+7)  /* FIP/FOP/FDP leaks through FXSAVE */
 #define X86_FEATURE_UP          (3*32+8) /* SMP kernel running on UP */
-
+#define X86_FEATURE_ARCH_PERFMON (3*32+9) /* Intel Architectural PerfMon */
 
 /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */
 #define X86_FEATURE_XMM3        (4*32+ 0) /* Streaming SIMD Extensions-3 */
diff --git a/include/asm-x86_64/intel_arch_perfmon.h b/include/asm-x86_64/intel_arch_perfmon.h
new file mode 100644
index 000000000000..59c396431569
--- /dev/null
+++ b/include/asm-x86_64/intel_arch_perfmon.h
@@ -0,0 +1,19 @@
+#ifndef X86_64_INTEL_ARCH_PERFMON_H
+#define X86_64_INTEL_ARCH_PERFMON_H 1
+
+#define MSR_ARCH_PERFMON_PERFCTR0               0xc1
+#define MSR_ARCH_PERFMON_PERFCTR1               0xc2
+
+#define MSR_ARCH_PERFMON_EVENTSEL0              0x186
+#define MSR_ARCH_PERFMON_EVENTSEL1              0x187
+
+#define ARCH_PERFMON_EVENTSEL0_ENABLE      (1 << 22)
+#define ARCH_PERFMON_EVENTSEL_INT          (1 << 20)
+#define ARCH_PERFMON_EVENTSEL_OS           (1 << 17)
+#define ARCH_PERFMON_EVENTSEL_USR          (1 << 16)
+
+#define ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL   (0x3c)
+#define ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK (0x00 << 8)
+#define ARCH_PERFMON_UNHALTED_CORE_CYCLES_PRESENT (1 << 0)
+
+#endif  /* X86_64_INTEL_ARCH_PERFMON_H */