[PATCH 12/16] x86: cpu common merge early_identify_cpu

Yinghai Lu
2008-09-05T03:13:29Z

arch/x86/kernel/cpu/common.c | 4 ++++
arch/x86/kernel/cpu/common_64.c | 19 ++++++++++++++++---
2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index ffc2f5e..61a7074 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -490,7 +490,11 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
*/
static void __init early_identify_cpu(struct cpuinfo_x86 *c)
{
+#ifdef CONFIG_X86_64
+ c->x86_clflush_size = 64;
+#else
c->x86_clflush_size = 32;
+#endif
c->x86_cache_alignment = c->x86_clflush_size;

if (!have_cpuid_p())
diff --git a/arch/x86/kernel/cpu/common_64.c b/arch/x86/kernel/cpu/common_64.c
index 75bb7ff..6475548 100644
--- a/arch/x86/kernel/cpu/common_64.c
+++ b/arch/x86/kernel/cpu/common_64.c
@@ -482,15 +482,28 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
#endif
}

-/* Do some early cpuid on the boot CPU to get some parameter that are
- needed before check_bugs. Everything advanced is in identify_cpu
- below. */
+/*
+ * Do minimum CPU detection early.
+ * Fields really needed: vendor, cpuid_level, family, model, mask,
+ * cache alignment.
+ * The others are not touched to avoid unwanted side effects.
+ *
+ * WARNING: this function is only called on the BP. Don't add code here
+ * that is supposed to run on all CPUs.
+ */
static void __init early_identify_cpu(struct cpuinfo_x86 *c)
{

+#ifdef CONFIG_X86_64
c->x86_clflush_size = 64;
+#else
+ c->x86_clflush_size = 32;
+#endif
c->x86_cache_alignment = c->x86_clflush_size;

+ if (!have_cpuid_p())
+ return;
+
memset(&c->x86_capability, 0, sizeof c->x86_capability);

c->extended_cpuid_level = 0;
--
1.5.4.5