tizen 2.3.1 release

[kernel/linux-3.0.git] / arch / x86 / kernel / cpu / amd.c

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index b13ed39..3f4b6da 100644 (file)
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -146,7 +146,6 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
 
 static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
 {
-#ifdef CONFIG_SMP
        /* calling is from identify_secondary_cpu() ? */
        if (!c->cpu_index)
                return;
@@ -190,7 +189,6 @@ static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
 
 valid_k7:
        ;
-#endif
 }
 
 static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
@@ -556,6 +554,20 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
                }
        }
 
+       /*
+        * The way access filter has a performance penalty on some workloads.
+        * Disable it on the affected CPUs.
+        */
+       if ((c->x86 == 0x15) &&
+           (c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
+               u64 val;
+
+               if (!rdmsrl_safe(0xc0011021, &val) && !(val & 0x1E)) {
+                       val |= 0x1E;
+                       checking_wrmsrl(0xc0011021, val);
+               }
+       }
+
        cpu_detect_cache_sizes(c);
 
        /* Multi core CPU? */