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Diffstat (limited to 'arch/x86/kernel/process_32.c')
-rw-r--r--arch/x86/kernel/process_32.c197
1 files changed, 68 insertions, 129 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 43930e73f657..f8476dfbb60d 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -36,6 +36,7 @@
#include <linux/personality.h>
#include <linux/tick.h>
#include <linux/percpu.h>
+#include <linux/prctl.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
@@ -45,7 +46,6 @@
#include <asm/processor.h>
#include <asm/i387.h>
#include <asm/desc.h>
-#include <asm/vm86.h>
#ifdef CONFIG_MATH_EMULATION
#include <asm/math_emu.h>
#endif
@@ -111,22 +111,13 @@ void default_idle(void)
*/
smp_mb();
- local_irq_disable();
- if (!need_resched()) {
- ktime_t t0, t1;
- u64 t0n, t1n;
-
- t0 = ktime_get();
- t0n = ktime_to_ns(t0);
+ if (!need_resched())
safe_halt(); /* enables interrupts racelessly */
- local_irq_disable();
- t1 = ktime_get();
- t1n = ktime_to_ns(t1);
- sched_clock_idle_wakeup_event(t1n - t0n);
- }
- local_irq_enable();
+ else
+ local_irq_enable();
current_thread_info()->status |= TS_POLLING;
} else {
+ local_irq_enable();
/* loop is done by the caller */
cpu_relax();
}
@@ -135,16 +126,6 @@ void default_idle(void)
EXPORT_SYMBOL(default_idle);
#endif
-/*
- * On SMP it's slightly faster (but much more power-consuming!)
- * to poll the ->work.need_resched flag instead of waiting for the
- * cross-CPU IPI to arrive. Use this option with caution.
- */
-static void poll_idle(void)
-{
- cpu_relax();
-}
-
#ifdef CONFIG_HOTPLUG_CPU
#include <asm/nmi.h>
/* We don't actually take CPU down, just spin without interrupts. */
@@ -202,6 +183,7 @@ void cpu_idle(void)
if (cpu_is_offline(cpu))
play_dead();
+ local_irq_disable();
__get_cpu_var(irq_stat).idle_timestamp = jiffies;
idle();
}
@@ -212,101 +194,6 @@ void cpu_idle(void)
}
}
-static void do_nothing(void *unused)
-{
-}
-
-/*
- * cpu_idle_wait - Used to ensure that all the CPUs discard old value of
- * pm_idle and update to new pm_idle value. Required while changing pm_idle
- * handler on SMP systems.
- *
- * Caller must have changed pm_idle to the new value before the call. Old
- * pm_idle value will not be used by any CPU after the return of this function.
- */
-void cpu_idle_wait(void)
-{
- smp_mb();
- /* kick all the CPUs so that they exit out of pm_idle */
- smp_call_function(do_nothing, NULL, 0, 1);
-}
-EXPORT_SYMBOL_GPL(cpu_idle_wait);
-
-/*
- * This uses new MONITOR/MWAIT instructions on P4 processors with PNI,
- * which can obviate IPI to trigger checking of need_resched.
- * We execute MONITOR against need_resched and enter optimized wait state
- * through MWAIT. Whenever someone changes need_resched, we would be woken
- * up from MWAIT (without an IPI).
- *
- * New with Core Duo processors, MWAIT can take some hints based on CPU
- * capability.
- */
-void mwait_idle_with_hints(unsigned long ax, unsigned long cx)
-{
- if (!need_resched()) {
- __monitor((void *)&current_thread_info()->flags, 0, 0);
- smp_mb();
- if (!need_resched())
- __mwait(ax, cx);
- }
-}
-
-/* Default MONITOR/MWAIT with no hints, used for default C1 state */
-static void mwait_idle(void)
-{
- local_irq_enable();
- mwait_idle_with_hints(0, 0);
-}
-
-static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
-{
- if (force_mwait)
- return 1;
- /* Any C1 states supported? */
- return c->cpuid_level >= 5 && ((cpuid_edx(5) >> 4) & 0xf) > 0;
-}
-
-void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
-{
- static int selected;
-
- if (selected)
- return;
-#ifdef CONFIG_X86_SMP
- if (pm_idle == poll_idle && smp_num_siblings > 1) {
- printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
- " performance may degrade.\n");
- }
-#endif
- if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) {
- /*
- * Skip, if setup has overridden idle.
- * One CPU supports mwait => All CPUs supports mwait
- */
- if (!pm_idle) {
- printk(KERN_INFO "using mwait in idle threads.\n");
- pm_idle = mwait_idle;
- }
- }
- selected = 1;
-}
-
-static int __init idle_setup(char *str)
-{
- if (!strcmp(str, "poll")) {
- printk("using polling idle threads.\n");
- pm_idle = poll_idle;
- } else if (!strcmp(str, "mwait"))
- force_mwait = 1;
- else
- return -1;
-
- boot_option_idle_override = 1;
- return 0;
-}
-early_param("idle", idle_setup);
-
void __show_registers(struct pt_regs *regs, int all)
{
unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
@@ -332,7 +219,7 @@ void __show_registers(struct pt_regs *regs, int all)
init_utsname()->version);
printk("EIP: %04x:[<%08lx>] EFLAGS: %08lx CPU: %d\n",
- 0xffff & regs->cs, regs->ip, regs->flags,
+ (u16)regs->cs, regs->ip, regs->flags,
smp_processor_id());
print_symbol("EIP is at %s\n", regs->ip);
@@ -341,8 +228,7 @@ void __show_registers(struct pt_regs *regs, int all)
printk("ESI: %08lx EDI: %08lx EBP: %08lx ESP: %08lx\n",
regs->si, regs->di, regs->bp, sp);
printk(" DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x\n",
- regs->ds & 0xffff, regs->es & 0xffff,
- regs->fs & 0xffff, gs, ss);
+ (u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, ss);
if (!all)
return;
@@ -513,11 +399,30 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
return err;
}
-#ifdef CONFIG_SECCOMP
+void
+start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
+{
+ __asm__("movl %0, %%gs" :: "r"(0));
+ regs->fs = 0;
+ set_fs(USER_DS);
+ regs->ds = __USER_DS;
+ regs->es = __USER_DS;
+ regs->ss = __USER_DS;
+ regs->cs = __USER_CS;
+ regs->ip = new_ip;
+ regs->sp = new_sp;
+ /*
+ * Free the old FP and other extended state
+ */
+ free_thread_xstate(current);
+}
+EXPORT_SYMBOL_GPL(start_thread);
+
static void hard_disable_TSC(void)
{
write_cr4(read_cr4() | X86_CR4_TSD);
}
+
void disable_TSC(void)
{
preempt_disable();
@@ -529,11 +434,47 @@ void disable_TSC(void)
hard_disable_TSC();
preempt_enable();
}
+
static void hard_enable_TSC(void)
{
write_cr4(read_cr4() & ~X86_CR4_TSD);
}
-#endif /* CONFIG_SECCOMP */
+
+static void enable_TSC(void)
+{
+ preempt_disable();
+ if (test_and_clear_thread_flag(TIF_NOTSC))
+ /*
+ * Must flip the CPU state synchronously with
+ * TIF_NOTSC in the current running context.
+ */
+ hard_enable_TSC();
+ preempt_enable();
+}
+
+int get_tsc_mode(unsigned long adr)
+{
+ unsigned int val;
+
+ if (test_thread_flag(TIF_NOTSC))
+ val = PR_TSC_SIGSEGV;
+ else
+ val = PR_TSC_ENABLE;
+
+ return put_user(val, (unsigned int __user *)adr);
+}
+
+int set_tsc_mode(unsigned int val)
+{
+ if (val == PR_TSC_SIGSEGV)
+ disable_TSC();
+ else if (val == PR_TSC_ENABLE)
+ enable_TSC();
+ else
+ return -EINVAL;
+
+ return 0;
+}
static noinline void
__switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
@@ -550,12 +491,12 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
/* we clear debugctl to make sure DS
* is not in use when we change it */
debugctl = 0;
- wrmsrl(MSR_IA32_DEBUGCTLMSR, 0);
+ update_debugctlmsr(0);
wrmsr(MSR_IA32_DS_AREA, next->ds_area_msr, 0);
}
if (next->debugctlmsr != debugctl)
- wrmsr(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr, 0);
+ update_debugctlmsr(next->debugctlmsr);
if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
set_debugreg(next->debugreg0, 0);
@@ -567,7 +508,6 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
set_debugreg(next->debugreg7, 7);
}
-#ifdef CONFIG_SECCOMP
if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
test_tsk_thread_flag(next_p, TIF_NOTSC)) {
/* prev and next are different */
@@ -576,7 +516,6 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
else
hard_enable_TSC();
}
-#endif
#ifdef X86_BTS
if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS))
@@ -658,7 +597,7 @@ struct task_struct * __switch_to(struct task_struct *prev_p, struct task_struct
/* we're going to use this soon, after a few expensive things */
if (next_p->fpu_counter > 5)
- prefetch(&next->i387.fxsave);
+ prefetch(next->xstate);
/*
* Reload esp0.
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