diff options
Diffstat (limited to 'arch/x86/xen/spinlock.c')
| -rw-r--r-- | arch/x86/xen/spinlock.c | 38 |
1 files changed, 18 insertions, 20 deletions
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c index 3776122c87cc..8e4efe0fb6f9 100644 --- a/arch/x86/xen/spinlock.c +++ b/arch/x86/xen/spinlock.c @@ -18,7 +18,6 @@ static DEFINE_PER_CPU(int, lock_kicker_irq) = -1; static DEFINE_PER_CPU(char *, irq_name); static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest); -static bool xen_pvspin = true; static void xen_qlock_kick(int cpu) { @@ -68,16 +67,14 @@ void xen_init_lock_cpu(int cpu) int irq; char *name; - if (!xen_pvspin) { - if (cpu == 0) - static_branch_disable(&virt_spin_lock_key); + if (nopvspin) return; - } WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n", cpu, per_cpu(lock_kicker_irq, cpu)); name = kasprintf(GFP_KERNEL, "spinlock%d", cpu); + per_cpu(irq_name, cpu) = name; irq = bind_ipi_to_irqhandler(XEN_SPIN_UNLOCK_VECTOR, cpu, dummy_handler, @@ -88,7 +85,6 @@ void xen_init_lock_cpu(int cpu) if (irq >= 0) { disable_irq(irq); /* make sure it's never delivered */ per_cpu(lock_kicker_irq, cpu) = irq; - per_cpu(irq_name, cpu) = name; } printk("cpu %d spinlock event irq %d\n", cpu, irq); @@ -96,13 +92,23 @@ void xen_init_lock_cpu(int cpu) void xen_uninit_lock_cpu(int cpu) { - if (!xen_pvspin) + int irq; + + if (nopvspin) return; - unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL); - per_cpu(lock_kicker_irq, cpu) = -1; kfree(per_cpu(irq_name, cpu)); per_cpu(irq_name, cpu) = NULL; + /* + * When booting the kernel with 'mitigations=auto,nosmt', the secondary + * CPUs are not activated, and lock_kicker_irq is not initialized. + */ + irq = per_cpu(lock_kicker_irq, cpu); + if (irq == -1) + return; + + unbind_from_irqhandler(irq, NULL); + per_cpu(lock_kicker_irq, cpu) = -1; } PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen); @@ -117,13 +123,13 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen); */ void __init xen_init_spinlocks(void) { - /* Don't need to use pvqspinlock code if there is only 1 vCPU. */ if (num_possible_cpus() == 1) - xen_pvspin = false; + nopvspin = true; - if (!xen_pvspin) { + if (nopvspin) { printk(KERN_DEBUG "xen: PV spinlocks disabled\n"); + static_branch_disable(&virt_spin_lock_key); return; } printk(KERN_DEBUG "xen: PV spinlocks enabled\n"); @@ -136,11 +142,3 @@ void __init xen_init_spinlocks(void) pv_ops.lock.kick = xen_qlock_kick; pv_ops.lock.vcpu_is_preempted = PV_CALLEE_SAVE(xen_vcpu_stolen); } - -static __init int xen_parse_nopvspin(char *arg) -{ - xen_pvspin = false; - return 0; -} -early_param("xen_nopvspin", xen_parse_nopvspin); - |