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authorDave Airlie <airlied@redhat.com>2015-04-20 11:32:26 +1000
committerDave Airlie <airlied@redhat.com>2015-04-20 13:05:20 +1000
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /arch/x86/kernel/cpu/common.c
parentcec32a47010647e8b0603726ebb75b990a4057a4 (diff)
parent09d51602cf84a1264946711dd4ea0dddbac599a1 (diff)
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Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c126
1 files changed, 93 insertions, 33 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 2346c95c6ab1..a62cf04dac8a 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -646,6 +646,30 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
c->x86_capability[10] = eax;
}
+ /* Additional Intel-defined flags: level 0x0000000F */
+ if (c->cpuid_level >= 0x0000000F) {
+ u32 eax, ebx, ecx, edx;
+
+ /* QoS sub-leaf, EAX=0Fh, ECX=0 */
+ cpuid_count(0x0000000F, 0, &eax, &ebx, &ecx, &edx);
+ c->x86_capability[11] = edx;
+ if (cpu_has(c, X86_FEATURE_CQM_LLC)) {
+ /* will be overridden if occupancy monitoring exists */
+ c->x86_cache_max_rmid = ebx;
+
+ /* QoS sub-leaf, EAX=0Fh, ECX=1 */
+ cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx);
+ c->x86_capability[12] = edx;
+ if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) {
+ c->x86_cache_max_rmid = ecx;
+ c->x86_cache_occ_scale = ebx;
+ }
+ } else {
+ c->x86_cache_max_rmid = -1;
+ c->x86_cache_occ_scale = -1;
+ }
+ }
+
/* AMD-defined flags: level 0x80000001 */
xlvl = cpuid_eax(0x80000000);
c->extended_cpuid_level = xlvl;
@@ -834,6 +858,20 @@ static void generic_identify(struct cpuinfo_x86 *c)
detect_nopl(c);
}
+static void x86_init_cache_qos(struct cpuinfo_x86 *c)
+{
+ /*
+ * The heavy lifting of max_rmid and cache_occ_scale are handled
+ * in get_cpu_cap(). Here we just set the max_rmid for the boot_cpu
+ * in case CQM bits really aren't there in this CPU.
+ */
+ if (c != &boot_cpu_data) {
+ boot_cpu_data.x86_cache_max_rmid =
+ min(boot_cpu_data.x86_cache_max_rmid,
+ c->x86_cache_max_rmid);
+ }
+}
+
/*
* This does the hard work of actually picking apart the CPU stuff...
*/
@@ -923,6 +961,7 @@ static void identify_cpu(struct cpuinfo_x86 *c)
init_hypervisor(c);
x86_init_rdrand(c);
+ x86_init_cache_qos(c);
/*
* Clear/Set all flags overriden by options, need do it
@@ -959,38 +998,37 @@ static void identify_cpu(struct cpuinfo_x86 *c)
#endif
}
-#ifdef CONFIG_X86_64
-#ifdef CONFIG_IA32_EMULATION
-/* May not be __init: called during resume */
-static void syscall32_cpu_init(void)
-{
- /* Load these always in case some future AMD CPU supports
- SYSENTER from compat mode too. */
- wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
- wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
- wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
-
- wrmsrl(MSR_CSTAR, ia32_cstar_target);
-}
-#endif /* CONFIG_IA32_EMULATION */
-#endif /* CONFIG_X86_64 */
-
+/*
+ * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions
+ * on 32-bit kernels:
+ */
#ifdef CONFIG_X86_32
void enable_sep_cpu(void)
{
- int cpu = get_cpu();
- struct tss_struct *tss = &per_cpu(init_tss, cpu);
+ struct tss_struct *tss;
+ int cpu;
- if (!boot_cpu_has(X86_FEATURE_SEP)) {
- put_cpu();
- return;
- }
+ cpu = get_cpu();
+ tss = &per_cpu(cpu_tss, cpu);
+
+ if (!boot_cpu_has(X86_FEATURE_SEP))
+ goto out;
+
+ /*
+ * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field --
+ * see the big comment in struct x86_hw_tss's definition.
+ */
tss->x86_tss.ss1 = __KERNEL_CS;
- tss->x86_tss.sp1 = sizeof(struct tss_struct) + (unsigned long) tss;
- wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);
- wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.sp1, 0);
- wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) ia32_sysenter_target, 0);
+ wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0);
+
+ wrmsr(MSR_IA32_SYSENTER_ESP,
+ (unsigned long)tss + offsetofend(struct tss_struct, SYSENTER_stack),
+ 0);
+
+ wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)ia32_sysenter_target, 0);
+
+out:
put_cpu();
}
#endif
@@ -1118,7 +1156,7 @@ static __init int setup_disablecpuid(char *arg)
__setup("clearcpuid=", setup_disablecpuid);
DEFINE_PER_CPU(unsigned long, kernel_stack) =
- (unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
+ (unsigned long)&init_thread_union + THREAD_SIZE;
EXPORT_PER_CPU_SYMBOL(kernel_stack);
#ifdef CONFIG_X86_64
@@ -1130,8 +1168,8 @@ DEFINE_PER_CPU_FIRST(union irq_stack_union,
irq_stack_union) __aligned(PAGE_SIZE) __visible;
/*
- * The following four percpu variables are hot. Align current_task to
- * cacheline size such that all four fall in the same cacheline.
+ * The following percpu variables are hot. Align current_task to
+ * cacheline size such that they fall in the same cacheline.
*/
DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
&init_task;
@@ -1171,10 +1209,23 @@ void syscall_init(void)
*/
wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32);
wrmsrl(MSR_LSTAR, system_call);
- wrmsrl(MSR_CSTAR, ignore_sysret);
#ifdef CONFIG_IA32_EMULATION
- syscall32_cpu_init();
+ wrmsrl(MSR_CSTAR, ia32_cstar_target);
+ /*
+ * This only works on Intel CPUs.
+ * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP.
+ * This does not cause SYSENTER to jump to the wrong location, because
+ * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit).
+ */
+ wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
+ wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
+ wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
+#else
+ wrmsrl(MSR_CSTAR, ignore_sysret);
+ wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG);
+ wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
+ wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL);
#endif
/* Flags to clear on syscall */
@@ -1226,6 +1277,15 @@ DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT;
EXPORT_PER_CPU_SYMBOL(__preempt_count);
DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
+/*
+ * On x86_32, vm86 modifies tss.sp0, so sp0 isn't a reliable way to find
+ * the top of the kernel stack. Use an extra percpu variable to track the
+ * top of the kernel stack directly.
+ */
+DEFINE_PER_CPU(unsigned long, cpu_current_top_of_stack) =
+ (unsigned long)&init_thread_union + THREAD_SIZE;
+EXPORT_PER_CPU_SYMBOL(cpu_current_top_of_stack);
+
#ifdef CONFIG_CC_STACKPROTECTOR
DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
#endif
@@ -1307,7 +1367,7 @@ void cpu_init(void)
*/
load_ucode_ap();
- t = &per_cpu(init_tss, cpu);
+ t = &per_cpu(cpu_tss, cpu);
oist = &per_cpu(orig_ist, cpu);
#ifdef CONFIG_NUMA
@@ -1391,7 +1451,7 @@ void cpu_init(void)
{
int cpu = smp_processor_id();
struct task_struct *curr = current;
- struct tss_struct *t = &per_cpu(init_tss, cpu);
+ struct tss_struct *t = &per_cpu(cpu_tss, cpu);
struct thread_struct *thread = &curr->thread;
wait_for_master_cpu(cpu);