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-rw-r--r--arch/x86/kernel/process.c213
1 files changed, 206 insertions, 7 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 6d12f7e37f8c..78533a519d8f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -1,8 +1,8 @@
1#include <linux/errno.h> 1#include <linux/errno.h>
2#include <linux/kernel.h> 2#include <linux/kernel.h>
3#include <linux/mm.h> 3#include <linux/mm.h>
4#include <asm/idle.h>
5#include <linux/smp.h> 4#include <linux/smp.h>
5#include <linux/prctl.h>
6#include <linux/slab.h> 6#include <linux/slab.h>
7#include <linux/sched.h> 7#include <linux/sched.h>
8#include <linux/module.h> 8#include <linux/module.h>
@@ -11,6 +11,9 @@
11#include <linux/ftrace.h> 11#include <linux/ftrace.h>
12#include <asm/system.h> 12#include <asm/system.h>
13#include <asm/apic.h> 13#include <asm/apic.h>
14#include <asm/idle.h>
15#include <asm/uaccess.h>
16#include <asm/i387.h>
14 17
15unsigned long idle_halt; 18unsigned long idle_halt;
16EXPORT_SYMBOL(idle_halt); 19EXPORT_SYMBOL(idle_halt);
@@ -56,6 +59,192 @@ void arch_task_cache_init(void)
56} 59}
57 60
58/* 61/*
62 * Free current thread data structures etc..
63 */
64void exit_thread(void)
65{
66 struct task_struct *me = current;
67 struct thread_struct *t = &me->thread;
68
69 if (me->thread.io_bitmap_ptr) {
70 struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
71
72 kfree(t->io_bitmap_ptr);
73 t->io_bitmap_ptr = NULL;
74 clear_thread_flag(TIF_IO_BITMAP);
75 /*
76 * Careful, clear this in the TSS too:
77 */
78 memset(tss->io_bitmap, 0xff, t->io_bitmap_max);
79 t->io_bitmap_max = 0;
80 put_cpu();
81 }
82
83 ds_exit_thread(current);
84}
85
86void flush_thread(void)
87{
88 struct task_struct *tsk = current;
89
90#ifdef CONFIG_X86_64
91 if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) {
92 clear_tsk_thread_flag(tsk, TIF_ABI_PENDING);
93 if (test_tsk_thread_flag(tsk, TIF_IA32)) {
94 clear_tsk_thread_flag(tsk, TIF_IA32);
95 } else {
96 set_tsk_thread_flag(tsk, TIF_IA32);
97 current_thread_info()->status |= TS_COMPAT;
98 }
99 }
100#endif
101
102 clear_tsk_thread_flag(tsk, TIF_DEBUG);
103
104 tsk->thread.debugreg0 = 0;
105 tsk->thread.debugreg1 = 0;
106 tsk->thread.debugreg2 = 0;
107 tsk->thread.debugreg3 = 0;
108 tsk->thread.debugreg6 = 0;
109 tsk->thread.debugreg7 = 0;
110 memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
111 /*
112 * Forget coprocessor state..
113 */
114 tsk->fpu_counter = 0;
115 clear_fpu(tsk);
116 clear_used_math();
117}
118
119static void hard_disable_TSC(void)
120{
121 write_cr4(read_cr4() | X86_CR4_TSD);
122}
123
124void disable_TSC(void)
125{
126 preempt_disable();
127 if (!test_and_set_thread_flag(TIF_NOTSC))
128 /*
129 * Must flip the CPU state synchronously with
130 * TIF_NOTSC in the current running context.
131 */
132 hard_disable_TSC();
133 preempt_enable();
134}
135
136static void hard_enable_TSC(void)
137{
138 write_cr4(read_cr4() & ~X86_CR4_TSD);
139}
140
141static void enable_TSC(void)
142{
143 preempt_disable();
144 if (test_and_clear_thread_flag(TIF_NOTSC))
145 /*
146 * Must flip the CPU state synchronously with
147 * TIF_NOTSC in the current running context.
148 */
149 hard_enable_TSC();
150 preempt_enable();
151}
152
153int get_tsc_mode(unsigned long adr)
154{
155 unsigned int val;
156
157 if (test_thread_flag(TIF_NOTSC))
158 val = PR_TSC_SIGSEGV;
159 else
160 val = PR_TSC_ENABLE;
161
162 return put_user(val, (unsigned int __user *)adr);
163}
164
165int set_tsc_mode(unsigned int val)
166{
167 if (val == PR_TSC_SIGSEGV)
168 disable_TSC();
169 else if (val == PR_TSC_ENABLE)
170 enable_TSC();
171 else
172 return -EINVAL;
173
174 return 0;
175}
176
177void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
178 struct tss_struct *tss)
179{
180 struct thread_struct *prev, *next;
181
182 prev = &prev_p->thread;
183 next = &next_p->thread;
184
185 if (test_tsk_thread_flag(next_p, TIF_DS_AREA_MSR) ||
186 test_tsk_thread_flag(prev_p, TIF_DS_AREA_MSR))
187 ds_switch_to(prev_p, next_p);
188 else if (next->debugctlmsr != prev->debugctlmsr)
189 update_debugctlmsr(next->debugctlmsr);
190
191 if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
192 set_debugreg(next->debugreg0, 0);
193 set_debugreg(next->debugreg1, 1);
194 set_debugreg(next->debugreg2, 2);
195 set_debugreg(next->debugreg3, 3);
196 /* no 4 and 5 */
197 set_debugreg(next->debugreg6, 6);
198 set_debugreg(next->debugreg7, 7);
199 }
200
201 if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
202 test_tsk_thread_flag(next_p, TIF_NOTSC)) {
203 /* prev and next are different */
204 if (test_tsk_thread_flag(next_p, TIF_NOTSC))
205 hard_disable_TSC();
206 else
207 hard_enable_TSC();
208 }
209
210 if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
211 /*
212 * Copy the relevant range of the IO bitmap.
213 * Normally this is 128 bytes or less:
214 */
215 memcpy(tss->io_bitmap, next->io_bitmap_ptr,
216 max(prev->io_bitmap_max, next->io_bitmap_max));
217 } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) {
218 /*
219 * Clear any possible leftover bits:
220 */
221 memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
222 }
223}
224
225int sys_fork(struct pt_regs *regs)
226{
227 return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
228}
229
230/*
231 * This is trivial, and on the face of it looks like it
232 * could equally well be done in user mode.
233 *
234 * Not so, for quite unobvious reasons - register pressure.
235 * In user mode vfork() cannot have a stack frame, and if
236 * done by calling the "clone()" system call directly, you
237 * do not have enough call-clobbered registers to hold all
238 * the information you need.
239 */
240int sys_vfork(struct pt_regs *regs)
241{
242 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0,
243 NULL, NULL);
244}
245
246
247/*
59 * Idle related variables and functions 248 * Idle related variables and functions
60 */ 249 */
61unsigned long boot_option_idle_override = 0; 250unsigned long boot_option_idle_override = 0;
@@ -135,7 +324,7 @@ void stop_this_cpu(void *dummy)
135 /* 324 /*
136 * Remove this CPU: 325 * Remove this CPU:
137 */ 326 */
138 cpu_clear(smp_processor_id(), cpu_online_map); 327 set_cpu_online(smp_processor_id(), false);
139 disable_local_APIC(); 328 disable_local_APIC();
140 329
141 for (;;) { 330 for (;;) {
@@ -285,12 +474,13 @@ static int __cpuinit check_c1e_idle(const struct cpuinfo_x86 *c)
285 return 1; 474 return 1;
286} 475}
287 476
288static cpumask_t c1e_mask = CPU_MASK_NONE; 477static cpumask_var_t c1e_mask;
289static int c1e_detected; 478static int c1e_detected;
290 479
291void c1e_remove_cpu(int cpu) 480void c1e_remove_cpu(int cpu)
292{ 481{
293 cpu_clear(cpu, c1e_mask); 482 if (c1e_mask != NULL)
483 cpumask_clear_cpu(cpu, c1e_mask);
294} 484}
295 485
296/* 486/*
@@ -319,8 +509,8 @@ static void c1e_idle(void)
319 if (c1e_detected) { 509 if (c1e_detected) {
320 int cpu = smp_processor_id(); 510 int cpu = smp_processor_id();
321 511
322 if (!cpu_isset(cpu, c1e_mask)) { 512 if (!cpumask_test_cpu(cpu, c1e_mask)) {
323 cpu_set(cpu, c1e_mask); 513 cpumask_set_cpu(cpu, c1e_mask);
324 /* 514 /*
325 * Force broadcast so ACPI can not interfere. Needs 515 * Force broadcast so ACPI can not interfere. Needs
326 * to run with interrupts enabled as it uses 516 * to run with interrupts enabled as it uses
@@ -350,7 +540,7 @@ static void c1e_idle(void)
350 540
351void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) 541void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
352{ 542{
353#ifdef CONFIG_X86_SMP 543#ifdef CONFIG_SMP
354 if (pm_idle == poll_idle && smp_num_siblings > 1) { 544 if (pm_idle == poll_idle && smp_num_siblings > 1) {
355 printk(KERN_WARNING "WARNING: polling idle and HT enabled," 545 printk(KERN_WARNING "WARNING: polling idle and HT enabled,"
356 " performance may degrade.\n"); 546 " performance may degrade.\n");
@@ -372,6 +562,15 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
372 pm_idle = default_idle; 562 pm_idle = default_idle;
373} 563}
374 564
565void __init init_c1e_mask(void)
566{
567 /* If we're using c1e_idle, we need to allocate c1e_mask. */
568 if (pm_idle == c1e_idle) {
569 alloc_cpumask_var(&c1e_mask, GFP_KERNEL);
570 cpumask_clear(c1e_mask);
571 }
572}
573
375static int __init idle_setup(char *str) 574static int __init idle_setup(char *str)
376{ 575{
377 if (!str) 576 if (!str)