From fa18f477d0987c011cce047a7c3cd1284f547a14 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 14 Nov 2006 16:57:46 +0100 Subject: [PATCH] x86: Add acpi_user_timer_override option for Asus boards Timer overrides are normally disabled on Nvidia board because they are commonly wrong, except on new ones with HPET support. Unfortunately there are quite some Asus boards around that don't have HPET, but need a timer override. We don't know yet how to handle this transparently, but at least add a command line option to force the timer override and let them boot. Cc: len.brown@intel.com Signed-off-by: Andi Kleen --- include/asm-i386/acpi.h | 1 + include/asm-x86_64/acpi.h | 1 + 2 files changed, 2 insertions(+) (limited to 'include') diff --git a/include/asm-i386/acpi.h b/include/asm-i386/acpi.h index 6016632d032f..c80b3a94511a 100644 --- a/include/asm-i386/acpi.h +++ b/include/asm-i386/acpi.h @@ -132,6 +132,7 @@ extern int acpi_gsi_to_irq(u32 gsi, unsigned int *irq); #ifdef CONFIG_X86_IO_APIC extern int acpi_skip_timer_override; +extern int acpi_use_timer_override; #endif static inline void acpi_noirq_set(void) { acpi_noirq = 1; } diff --git a/include/asm-x86_64/acpi.h b/include/asm-x86_64/acpi.h index ed59aa4c6ff9..9d1916e59c04 100644 --- a/include/asm-x86_64/acpi.h +++ b/include/asm-x86_64/acpi.h @@ -163,6 +163,7 @@ extern u8 x86_acpiid_to_apicid[]; #define ARCH_HAS_POWER_INIT 1 extern int acpi_skip_timer_override; +extern int acpi_use_timer_override; #endif /*__KERNEL__*/ -- cgit v1.2.3 From 8c131af1db510793f87dc43edbc8950a35370df3 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 14 Nov 2006 16:57:46 +0100 Subject: [PATCH] x86-64: Fix vgetcpu when CONFIG_HOTPLUG_CPU is disabled The vgetcpu per CPU initialization previously relied on CPU hotplug events for all CPUs to initialize the per CPU state. That only worked only on kernels with CONFIG_HOTPLUG_CPU enabled. On the others some CPUs didn't get their state initialized properly and vgetcpu wouldn't work. Change the initialization sequence to instead run in a normal initcall (which runs after the normal CPU bootup) and initialize all running CPUs there. Later hotplug CPUs are still handled with an hotplug notifier. This actually simplifies the code somewhat. Signed-off-by: Andi Kleen --- arch/x86_64/kernel/smp.c | 3 +-- arch/x86_64/kernel/time.c | 11 ----------- arch/x86_64/kernel/vsyscall.c | 45 ++++++++++++++++++++++++------------------- include/asm-x86_64/vsyscall.h | 2 -- 4 files changed, 26 insertions(+), 35 deletions(-) (limited to 'include') diff --git a/arch/x86_64/kernel/smp.c b/arch/x86_64/kernel/smp.c index 4f67697f5036..9f74c883568c 100644 --- a/arch/x86_64/kernel/smp.c +++ b/arch/x86_64/kernel/smp.c @@ -376,9 +376,8 @@ int smp_call_function_single (int cpu, void (*func) (void *info), void *info, /* prevent preemption and reschedule on another processor */ int me = get_cpu(); if (cpu == me) { - WARN_ON(1); put_cpu(); - return -EBUSY; + return 0; } spin_lock_bh(&call_lock); __smp_call_function_single(cpu, func, info, nonatomic, wait); diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c index 88722f11ca13..e3ef544d2cfb 100644 --- a/arch/x86_64/kernel/time.c +++ b/arch/x86_64/kernel/time.c @@ -876,15 +876,6 @@ static struct irqaction irq0 = { timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL }; -static int __cpuinit -time_cpu_notifier(struct notifier_block *nb, unsigned long action, void *hcpu) -{ - unsigned cpu = (unsigned long) hcpu; - if (action == CPU_ONLINE) - vsyscall_set_cpu(cpu); - return NOTIFY_DONE; -} - void __init time_init(void) { if (nohpet) @@ -925,8 +916,6 @@ void __init time_init(void) vxtime.last_tsc = get_cycles_sync(); set_cyc2ns_scale(cpu_khz); setup_irq(0, &irq0); - hotcpu_notifier(time_cpu_notifier, 0); - time_cpu_notifier(NULL, CPU_ONLINE, (void *)(long)smp_processor_id()); #ifndef CONFIG_SMP time_init_gtod(); diff --git a/arch/x86_64/kernel/vsyscall.c b/arch/x86_64/kernel/vsyscall.c index a98b460af6a1..a730bacecb0b 100644 --- a/arch/x86_64/kernel/vsyscall.c +++ b/arch/x86_64/kernel/vsyscall.c @@ -27,6 +27,9 @@ #include #include #include +#include +#include +#include #include #include @@ -243,32 +246,17 @@ static ctl_table kernel_root_table2[] = { #endif -static void __cpuinit write_rdtscp_cb(void *info) -{ - write_rdtscp_aux((unsigned long)info); -} - -void __cpuinit vsyscall_set_cpu(int cpu) +/* Assume __initcall executes before all user space. Hopefully kmod + doesn't violate that. We'll find out if it does. */ +static void __cpuinit vsyscall_set_cpu(int cpu) { unsigned long *d; unsigned long node = 0; #ifdef CONFIG_NUMA node = cpu_to_node[cpu]; #endif - if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP)) { - void *info = (void *)((node << 12) | cpu); - /* Can happen on preemptive kernel */ - if (get_cpu() == cpu) - write_rdtscp_cb(info); -#ifdef CONFIG_SMP - else { - /* the notifier is unfortunately not executed on the - target CPU */ - smp_call_function_single(cpu,write_rdtscp_cb,info,0,1); - } -#endif - put_cpu(); - } + if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP)) + write_rdtscp_aux((node << 12) | cpu); /* Store cpu number in limit so that it can be loaded quickly in user space in vgetcpu. @@ -280,6 +268,21 @@ void __cpuinit vsyscall_set_cpu(int cpu) *d |= (node >> 4) << 48; } +static void __cpuinit cpu_vsyscall_init(void *arg) +{ + /* preemption should be already off */ + vsyscall_set_cpu(raw_smp_processor_id()); +} + +static int __cpuinit +cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg) +{ + long cpu = (long)arg; + if (action == CPU_ONLINE) + smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 0, 1); + return NOTIFY_DONE; +} + static void __init map_vsyscall(void) { extern char __vsyscall_0; @@ -299,6 +302,8 @@ static int __init vsyscall_init(void) #ifdef CONFIG_SYSCTL register_sysctl_table(kernel_root_table2, 0); #endif + on_each_cpu(cpu_vsyscall_init, NULL, 0, 1); + hotcpu_notifier(cpu_vsyscall_notifier, 0); return 0; } diff --git a/include/asm-x86_64/vsyscall.h b/include/asm-x86_64/vsyscall.h index fd452fc2c037..01d1c17e2849 100644 --- a/include/asm-x86_64/vsyscall.h +++ b/include/asm-x86_64/vsyscall.h @@ -59,8 +59,6 @@ extern seqlock_t xtime_lock; extern int sysctl_vsyscall; -extern void vsyscall_set_cpu(int cpu); - #define ARCH_HAVE_XTIME_LOCK 1 #endif /* __KERNEL__ */ -- cgit v1.2.3 From 9446868b5383eb87f76b2d4389dea4bb968a6657 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 14 Nov 2006 16:57:46 +0100 Subject: [PATCH] x86-64: Fix race in exit_idle When another interrupt happens in exit_idle the exit idle notifier could be called an incorrect number of times. Add a test_and_clear_bit_pda and use it handle the bit atomically against interrupts to avoid this. Pointed out by Stephane Eranian Signed-off-by: Andi Kleen --- arch/x86_64/kernel/process.c | 3 +-- include/asm-x86_64/pda.h | 9 +++++++++ 2 files changed, 10 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c index 49f7fac6229e..f6226055d53d 100644 --- a/arch/x86_64/kernel/process.c +++ b/arch/x86_64/kernel/process.c @@ -88,9 +88,8 @@ void enter_idle(void) static void __exit_idle(void) { - if (read_pda(isidle) == 0) + if (test_and_clear_bit_pda(0, isidle) == 0) return; - write_pda(isidle, 0); atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL); } diff --git a/include/asm-x86_64/pda.h b/include/asm-x86_64/pda.h index 14996d962bac..5642634843c4 100644 --- a/include/asm-x86_64/pda.h +++ b/include/asm-x86_64/pda.h @@ -109,6 +109,15 @@ extern struct x8664_pda _proxy_pda; #define sub_pda(field,val) pda_to_op("sub",field,val) #define or_pda(field,val) pda_to_op("or",field,val) +/* This is not atomic against other CPUs -- CPU preemption needs to be off */ +#define test_and_clear_bit_pda(bit,field) ({ \ + int old__; \ + asm volatile("btr %2,%%gs:%c3\n\tsbbl %0,%0" \ + : "=r" (old__), "+m" (_proxy_pda.field) \ + : "dIr" (bit), "i" (pda_offset(field)) : "memory"); \ + old__; \ +}) + #endif #define PDA_STACKOFFSET (5*8) -- cgit v1.2.3