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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-19 17:36:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-19 17:36:08 -0700
commitdf48d8716eab9608fe93924e4ae06ff110e8674f (patch)
tree0fe10733a414b3651e1dae29518b7960a4da0aa4 /arch/x86/kernel/cpu/intel.c
parentacd30250d7d0f495685d1c7c6184636a22fcdf7f (diff)
parent29510ec3b626c86de9707bb8904ff940d430289b (diff)
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Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (107 commits) perf stat: Add more cache-miss percentage printouts perf stat: Add -d -d and -d -d -d options to show more CPU events ftrace/kbuild: Add recordmcount files to force full build ftrace: Add self-tests for multiple function trace users ftrace: Modify ftrace_set_filter/notrace to take ops ftrace: Allow dynamically allocated function tracers ftrace: Implement separate user function filtering ftrace: Free hash with call_rcu_sched() ftrace: Have global_ops store the functions that are to be traced ftrace: Add ops parameter to ftrace_startup/shutdown functions ftrace: Add enabled_functions file ftrace: Use counters to enable functions to trace ftrace: Separate hash allocation and assignment ftrace: Create a global_ops to hold the filter and notrace hashes ftrace: Use hash instead for FTRACE_FL_FILTER ftrace: Replace FTRACE_FL_NOTRACE flag with a hash of ignored functions perf bench, x86: Add alternatives-asm.h wrapper x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limit x86, mem: memset_64.S: Optimize memset by enhanced REP MOVSB/STOSB x86, mem: memmove_64.S: Optimize memmove by enhanced REP MOVSB/STOSB ...
Diffstat (limited to 'arch/x86/kernel/cpu/intel.c')
-rw-r--r--arch/x86/kernel/cpu/intel.c19
1 files changed, 15 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index df86bc8c859d..fc73a34ba8c9 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -29,10 +29,10 @@
static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
{
+ u64 misc_enable;
+
/* Unmask CPUID levels if masked: */
if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
- u64 misc_enable;
-
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
@@ -118,8 +118,6 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
* (model 2) with the same problem.
*/
if (c->x86 == 15) {
- u64 misc_enable;
-
rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
if (misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING) {
@@ -130,6 +128,19 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
}
}
#endif
+
+ /*
+ * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
+ * clear the fast string and enhanced fast string CPU capabilities.
+ */
+ if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
+ rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
+ if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
+ printk(KERN_INFO "Disabled fast string operations\n");
+ setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
+ setup_clear_cpu_cap(X86_FEATURE_ERMS);
+ }
+ }
}
#ifdef CONFIG_X86_32