diff options
| author | Tony Luck <tony.luck@intel.com> | 2022-01-31 15:01:09 -0800 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-02-01 16:29:26 +0100 |
| commit | 822ccfade55b6be7977b364356fcf2d78d8a373a (patch) | |
| tree | 801825ff6ecde7e19bad0c0110fccb0cbae18863 | |
| parent | 00a2f23eef7d1fa6c2dfdc613857b84fbf5e2b3b (diff) | |
| download | linux-822ccfade55b6be7977b364356fcf2d78d8a373a.tar.bz2 | |
x86/cpu: Read/save PPIN MSR during initialization
Currently, the PPIN (Protected Processor Inventory Number) MSR is read
by every CPU that processes a machine check, CMCI, or just polls machine
check banks from a periodic timer. This is not a "fast" MSR, so this
adds to overhead of processing errors.
Add a new "ppin" field to the cpuinfo_x86 structure. Read and save the
PPIN during initialization. Use this copy in mce_setup() instead of
reading the MSR.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220131230111.2004669-4-tony.luck@intel.com
| -rw-r--r-- | arch/x86/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 7 |
3 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 2c5f12ae7d04..a87e7c33d5ac 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -119,6 +119,8 @@ struct cpuinfo_x86 { int x86_cache_mbm_width_offset; int x86_power; unsigned long loops_per_jiffy; + /* protected processor identification number */ + u64 ppin; /* cpuid returned max cores value: */ u16 x86_max_cores; u16 apicid; diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 0681c69a1f09..64deb7727d00 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -91,14 +91,17 @@ DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id) = BAD_APICID; static struct ppin_info { int feature; int msr_ppin_ctl; + int msr_ppin; } ppin_info[] = { [X86_VENDOR_INTEL] = { .feature = X86_FEATURE_INTEL_PPIN, .msr_ppin_ctl = MSR_PPIN_CTL, + .msr_ppin = MSR_PPIN }, [X86_VENDOR_AMD] = { .feature = X86_FEATURE_AMD_PPIN, .msr_ppin_ctl = MSR_AMD_PPIN_CTL, + .msr_ppin = MSR_AMD_PPIN }, }; @@ -153,6 +156,7 @@ static void ppin_init(struct cpuinfo_x86 *c) /* Is the enable bit set? */ if (val & 2UL) { + c->ppin = __rdmsr(info->msr_ppin); set_cpu_cap(c, info->feature); return; } diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 5818b837fd4d..4f1e825033ce 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -138,12 +138,7 @@ void mce_setup(struct mce *m) m->socketid = cpu_data(m->extcpu).phys_proc_id; m->apicid = cpu_data(m->extcpu).initial_apicid; m->mcgcap = __rdmsr(MSR_IA32_MCG_CAP); - - if (this_cpu_has(X86_FEATURE_INTEL_PPIN)) - m->ppin = __rdmsr(MSR_PPIN); - else if (this_cpu_has(X86_FEATURE_AMD_PPIN)) - m->ppin = __rdmsr(MSR_AMD_PPIN); - + m->ppin = cpu_data(m->extcpu).ppin; m->microcode = boot_cpu_data.microcode; } |