diff options
Diffstat (limited to 'arch/x86/kernel/smpboot.c')
| -rw-r--r-- | arch/x86/kernel/smpboot.c | 64 |
1 files changed, 43 insertions, 21 deletions
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index ffbd9a3d78d8..27aa04a95702 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -51,11 +51,11 @@ #include <linux/err.h> #include <linux/nmi.h> #include <linux/tboot.h> -#include <linux/stackprotector.h> #include <linux/gfp.h> #include <linux/cpuidle.h> #include <linux/numa.h> #include <linux/pgtable.h> +#include <linux/overflow.h> #include <asm/acpi.h> #include <asm/desc.h> @@ -80,6 +80,7 @@ #include <asm/cpu_device_id.h> #include <asm/spec-ctrl.h> #include <asm/hw_irq.h> +#include <asm/stackprotector.h> /* representing HT siblings of each logical CPU */ DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); @@ -259,21 +260,10 @@ static void notrace start_secondary(void *unused) /* enable local interrupts */ local_irq_enable(); - /* to prevent fake stack check failure in clock setup */ - boot_init_stack_canary(); - x86_cpuinit.setup_percpu_clockev(); 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(); } /** @@ -1011,6 +1001,7 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle) alternatives_enable_smp(); per_cpu(current_task, cpu) = idle; + cpu_init_stack_canary(cpu, idle); /* Initialize the interrupt stack(s) */ ret = irq_init_percpu_irqstack(cpu); @@ -1777,6 +1768,7 @@ void native_play_dead(void) #endif +#ifdef CONFIG_X86_64 /* * APERF/MPERF frequency ratio computation. * @@ -1975,6 +1967,7 @@ static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) static bool intel_set_max_freq_ratio(void) { u64 base_freq, turbo_freq; + u64 turbo_ratio; if (slv_set_max_freq_ratio(&base_freq, &turbo_freq)) goto out; @@ -2000,15 +1993,23 @@ out: /* * Some hypervisors advertise X86_FEATURE_APERFMPERF * but then fill all MSR's with zeroes. + * Some CPUs have turbo boost but don't declare any turbo ratio + * in MSR_TURBO_RATIO_LIMIT. */ - if (!base_freq) { - pr_debug("Couldn't determine cpu base frequency, necessary for scale-invariant accounting.\n"); + if (!base_freq || !turbo_freq) { + pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n"); return false; } - arch_turbo_freq_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, - base_freq); + turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq); + if (!turbo_ratio) { + pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n"); + return false; + } + + arch_turbo_freq_ratio = turbo_ratio; arch_set_max_freq_ratio(turbo_disabled()); + return true; } @@ -2048,11 +2049,19 @@ static void init_freq_invariance(bool secondary) } } +static void disable_freq_invariance_workfn(struct work_struct *work) +{ + static_branch_disable(&arch_scale_freq_key); +} + +static DECLARE_WORK(disable_freq_invariance_work, + disable_freq_invariance_workfn); + DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE; void arch_scale_freq_tick(void) { - u64 freq_scale; + u64 freq_scale = SCHED_CAPACITY_SCALE; u64 aperf, mperf; u64 acnt, mcnt; @@ -2064,19 +2073,32 @@ void arch_scale_freq_tick(void) acnt = aperf - this_cpu_read(arch_prev_aperf); mcnt = mperf - this_cpu_read(arch_prev_mperf); - if (!mcnt) - return; this_cpu_write(arch_prev_aperf, aperf); this_cpu_write(arch_prev_mperf, mperf); - acnt <<= 2*SCHED_CAPACITY_SHIFT; - mcnt *= arch_max_freq_ratio; + if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt)) + goto error; + + if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt) + goto error; freq_scale = div64_u64(acnt, mcnt); + if (!freq_scale) + goto error; if (freq_scale > SCHED_CAPACITY_SCALE) freq_scale = SCHED_CAPACITY_SCALE; this_cpu_write(arch_freq_scale, freq_scale); + return; + +error: + pr_warn("Scheduler frequency invariance went wobbly, disabling!\n"); + schedule_work(&disable_freq_invariance_work); +} +#else +static inline void init_freq_invariance(bool secondary) +{ } +#endif /* CONFIG_X86_64 */ |