diff options
Diffstat (limited to 'arch/x86/kernel/smpboot.c')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 55 |
1 files changed, 41 insertions, 14 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index fe3ab9632f3b..2f24c334a938 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -147,7 +147,7 @@ static inline void smpboot_restore_warm_reset_vector(void) *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0; } -static void init_freq_invariance(void); +static void init_freq_invariance(bool secondary); /* * Report back to the Boot Processor during boot time or to the caller processor @@ -185,7 +185,7 @@ static void smp_callin(void) */ set_cpu_sibling_map(raw_smp_processor_id()); - init_freq_invariance(); + init_freq_invariance(true); /* * Get our bogomips. @@ -266,6 +266,14 @@ static void notrace start_secondary(void *unused) wmb(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); + + /* + * Prevent tail call to cpu_startup_entry() because the stack protector + * guard has been changed a couple of function calls up, in + * boot_init_stack_canary() and must not be checked before tail calling + * another function. + */ + prevent_tail_call_optimization(); } /** @@ -1341,7 +1349,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) set_sched_topology(x86_topology); set_cpu_sibling_map(0); - init_freq_invariance(); + init_freq_invariance(false); smp_sanity_check(); switch (apic_intr_mode) { @@ -1877,9 +1885,6 @@ static bool knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int err, i; u64 msr; - if (!x86_match_cpu(has_knl_turbo_ratio_limits)) - return false; - err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); if (err) return false; @@ -1945,18 +1950,23 @@ static bool skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size) static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) { + u64 msr; int err; err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); if (err) return false; - err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, turbo_freq); + err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr); if (err) return false; - *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ - *turbo_freq = (*turbo_freq >> 24) & 0xFF; /* 4C turbo */ + *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ + *turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */ + + /* The CPU may have less than 4 cores */ + if (!*turbo_freq) + *turbo_freq = msr & 0xFF; /* 1C turbo */ return true; } @@ -1972,7 +1982,8 @@ static bool intel_set_max_freq_ratio(void) skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) goto out; - if (knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) + if (x86_match_cpu(has_knl_turbo_ratio_limits) && + knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) goto out; if (x86_match_cpu(has_skx_turbo_ratio_limits) && @@ -1985,13 +1996,22 @@ static bool intel_set_max_freq_ratio(void) return false; out: + /* + * Some hypervisors advertise X86_FEATURE_APERFMPERF + * but then fill all MSR's with zeroes. + */ + if (!base_freq) { + pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n"); + return false; + } + arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq); arch_set_max_freq_ratio(turbo_disabled()); return true; } -static void init_counter_refs(void *arg) +static void init_counter_refs(void) { u64 aperf, mperf; @@ -2002,18 +2022,25 @@ static void init_counter_refs(void *arg) this_cpu_write(arch_prev_mperf, mperf); } -static void init_freq_invariance(void) +static void init_freq_invariance(bool secondary) { bool ret = false; - if (smp_processor_id() != 0 || !boot_cpu_has(X86_FEATURE_APERFMPERF)) + if (!boot_cpu_has(X86_FEATURE_APERFMPERF)) return; + if (secondary) { + if (static_branch_likely(&arch_scale_freq_key)) { + init_counter_refs(); + } + return; + } + if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) ret = intel_set_max_freq_ratio(); if (ret) { - on_each_cpu(init_counter_refs, NULL, 1); + init_counter_refs(); static_branch_enable(&arch_scale_freq_key); } else { pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n"); |