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Commit | Line | Data |
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61c4628b SS |
1 | #include <linux/errno.h> |
2 | #include <linux/kernel.h> | |
3 | #include <linux/mm.h> | |
4 | #include <linux/smp.h> | |
389d1fb1 | 5 | #include <linux/prctl.h> |
61c4628b SS |
6 | #include <linux/slab.h> |
7 | #include <linux/sched.h> | |
7f424a8b PZ |
8 | #include <linux/module.h> |
9 | #include <linux/pm.h> | |
aa276e1c | 10 | #include <linux/clockchips.h> |
9d62dcdf | 11 | #include <linux/random.h> |
61613521 | 12 | #include <trace/events/power.h> |
c1e3b377 | 13 | #include <asm/system.h> |
d3ec5cae | 14 | #include <asm/apic.h> |
2c1b284e | 15 | #include <asm/syscalls.h> |
389d1fb1 JF |
16 | #include <asm/idle.h> |
17 | #include <asm/uaccess.h> | |
18 | #include <asm/i387.h> | |
2311f0de | 19 | #include <asm/ds.h> |
c1e3b377 ZY |
20 | |
21 | unsigned long idle_halt; | |
22 | EXPORT_SYMBOL(idle_halt); | |
da5e09a1 ZY |
23 | unsigned long idle_nomwait; |
24 | EXPORT_SYMBOL(idle_nomwait); | |
61c4628b | 25 | |
aa283f49 | 26 | struct kmem_cache *task_xstate_cachep; |
61c4628b SS |
27 | |
28 | int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) | |
29 | { | |
30 | *dst = *src; | |
aa283f49 SS |
31 | if (src->thread.xstate) { |
32 | dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep, | |
33 | GFP_KERNEL); | |
34 | if (!dst->thread.xstate) | |
35 | return -ENOMEM; | |
36 | WARN_ON((unsigned long)dst->thread.xstate & 15); | |
37 | memcpy(dst->thread.xstate, src->thread.xstate, xstate_size); | |
38 | } | |
61c4628b SS |
39 | return 0; |
40 | } | |
41 | ||
aa283f49 | 42 | void free_thread_xstate(struct task_struct *tsk) |
61c4628b | 43 | { |
aa283f49 SS |
44 | if (tsk->thread.xstate) { |
45 | kmem_cache_free(task_xstate_cachep, tsk->thread.xstate); | |
46 | tsk->thread.xstate = NULL; | |
47 | } | |
2311f0de MM |
48 | |
49 | WARN(tsk->thread.ds_ctx, "leaking DS context\n"); | |
aa283f49 SS |
50 | } |
51 | ||
aa283f49 SS |
52 | void free_thread_info(struct thread_info *ti) |
53 | { | |
54 | free_thread_xstate(ti->task); | |
1679f271 | 55 | free_pages((unsigned long)ti, get_order(THREAD_SIZE)); |
61c4628b SS |
56 | } |
57 | ||
58 | void arch_task_cache_init(void) | |
59 | { | |
60 | task_xstate_cachep = | |
61 | kmem_cache_create("task_xstate", xstate_size, | |
62 | __alignof__(union thread_xstate), | |
2dff4405 | 63 | SLAB_PANIC | SLAB_NOTRACK, NULL); |
61c4628b | 64 | } |
7f424a8b | 65 | |
389d1fb1 JF |
66 | /* |
67 | * Free current thread data structures etc.. | |
68 | */ | |
69 | void exit_thread(void) | |
70 | { | |
71 | struct task_struct *me = current; | |
72 | struct thread_struct *t = &me->thread; | |
250981e6 | 73 | unsigned long *bp = t->io_bitmap_ptr; |
389d1fb1 | 74 | |
250981e6 | 75 | if (bp) { |
389d1fb1 JF |
76 | struct tss_struct *tss = &per_cpu(init_tss, get_cpu()); |
77 | ||
389d1fb1 JF |
78 | t->io_bitmap_ptr = NULL; |
79 | clear_thread_flag(TIF_IO_BITMAP); | |
80 | /* | |
81 | * Careful, clear this in the TSS too: | |
82 | */ | |
83 | memset(tss->io_bitmap, 0xff, t->io_bitmap_max); | |
84 | t->io_bitmap_max = 0; | |
85 | put_cpu(); | |
250981e6 | 86 | kfree(bp); |
389d1fb1 | 87 | } |
389d1fb1 JF |
88 | } |
89 | ||
90 | void flush_thread(void) | |
91 | { | |
92 | struct task_struct *tsk = current; | |
93 | ||
94 | #ifdef CONFIG_X86_64 | |
95 | if (test_tsk_thread_flag(tsk, TIF_ABI_PENDING)) { | |
96 | clear_tsk_thread_flag(tsk, TIF_ABI_PENDING); | |
97 | if (test_tsk_thread_flag(tsk, TIF_IA32)) { | |
98 | clear_tsk_thread_flag(tsk, TIF_IA32); | |
99 | } else { | |
100 | set_tsk_thread_flag(tsk, TIF_IA32); | |
101 | current_thread_info()->status |= TS_COMPAT; | |
102 | } | |
103 | } | |
104 | #endif | |
105 | ||
106 | clear_tsk_thread_flag(tsk, TIF_DEBUG); | |
107 | ||
108 | tsk->thread.debugreg0 = 0; | |
109 | tsk->thread.debugreg1 = 0; | |
110 | tsk->thread.debugreg2 = 0; | |
111 | tsk->thread.debugreg3 = 0; | |
112 | tsk->thread.debugreg6 = 0; | |
113 | tsk->thread.debugreg7 = 0; | |
114 | memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); | |
115 | /* | |
116 | * Forget coprocessor state.. | |
117 | */ | |
118 | tsk->fpu_counter = 0; | |
119 | clear_fpu(tsk); | |
120 | clear_used_math(); | |
121 | } | |
122 | ||
123 | static void hard_disable_TSC(void) | |
124 | { | |
125 | write_cr4(read_cr4() | X86_CR4_TSD); | |
126 | } | |
127 | ||
128 | void disable_TSC(void) | |
129 | { | |
130 | preempt_disable(); | |
131 | if (!test_and_set_thread_flag(TIF_NOTSC)) | |
132 | /* | |
133 | * Must flip the CPU state synchronously with | |
134 | * TIF_NOTSC in the current running context. | |
135 | */ | |
136 | hard_disable_TSC(); | |
137 | preempt_enable(); | |
138 | } | |
139 | ||
140 | static void hard_enable_TSC(void) | |
141 | { | |
142 | write_cr4(read_cr4() & ~X86_CR4_TSD); | |
143 | } | |
144 | ||
145 | static void enable_TSC(void) | |
146 | { | |
147 | preempt_disable(); | |
148 | if (test_and_clear_thread_flag(TIF_NOTSC)) | |
149 | /* | |
150 | * Must flip the CPU state synchronously with | |
151 | * TIF_NOTSC in the current running context. | |
152 | */ | |
153 | hard_enable_TSC(); | |
154 | preempt_enable(); | |
155 | } | |
156 | ||
157 | int get_tsc_mode(unsigned long adr) | |
158 | { | |
159 | unsigned int val; | |
160 | ||
161 | if (test_thread_flag(TIF_NOTSC)) | |
162 | val = PR_TSC_SIGSEGV; | |
163 | else | |
164 | val = PR_TSC_ENABLE; | |
165 | ||
166 | return put_user(val, (unsigned int __user *)adr); | |
167 | } | |
168 | ||
169 | int set_tsc_mode(unsigned int val) | |
170 | { | |
171 | if (val == PR_TSC_SIGSEGV) | |
172 | disable_TSC(); | |
173 | else if (val == PR_TSC_ENABLE) | |
174 | enable_TSC(); | |
175 | else | |
176 | return -EINVAL; | |
177 | ||
178 | return 0; | |
179 | } | |
180 | ||
181 | void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, | |
182 | struct tss_struct *tss) | |
183 | { | |
184 | struct thread_struct *prev, *next; | |
185 | ||
186 | prev = &prev_p->thread; | |
187 | next = &next_p->thread; | |
188 | ||
189 | if (test_tsk_thread_flag(next_p, TIF_DS_AREA_MSR) || | |
190 | test_tsk_thread_flag(prev_p, TIF_DS_AREA_MSR)) | |
191 | ds_switch_to(prev_p, next_p); | |
192 | else if (next->debugctlmsr != prev->debugctlmsr) | |
193 | update_debugctlmsr(next->debugctlmsr); | |
194 | ||
195 | if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { | |
196 | set_debugreg(next->debugreg0, 0); | |
197 | set_debugreg(next->debugreg1, 1); | |
198 | set_debugreg(next->debugreg2, 2); | |
199 | set_debugreg(next->debugreg3, 3); | |
200 | /* no 4 and 5 */ | |
201 | set_debugreg(next->debugreg6, 6); | |
202 | set_debugreg(next->debugreg7, 7); | |
203 | } | |
204 | ||
205 | if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^ | |
206 | test_tsk_thread_flag(next_p, TIF_NOTSC)) { | |
207 | /* prev and next are different */ | |
208 | if (test_tsk_thread_flag(next_p, TIF_NOTSC)) | |
209 | hard_disable_TSC(); | |
210 | else | |
211 | hard_enable_TSC(); | |
212 | } | |
213 | ||
214 | if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) { | |
215 | /* | |
216 | * Copy the relevant range of the IO bitmap. | |
217 | * Normally this is 128 bytes or less: | |
218 | */ | |
219 | memcpy(tss->io_bitmap, next->io_bitmap_ptr, | |
220 | max(prev->io_bitmap_max, next->io_bitmap_max)); | |
221 | } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) { | |
222 | /* | |
223 | * Clear any possible leftover bits: | |
224 | */ | |
225 | memset(tss->io_bitmap, 0xff, prev->io_bitmap_max); | |
226 | } | |
227 | } | |
228 | ||
229 | int sys_fork(struct pt_regs *regs) | |
230 | { | |
231 | return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL); | |
232 | } | |
233 | ||
234 | /* | |
235 | * This is trivial, and on the face of it looks like it | |
236 | * could equally well be done in user mode. | |
237 | * | |
238 | * Not so, for quite unobvious reasons - register pressure. | |
239 | * In user mode vfork() cannot have a stack frame, and if | |
240 | * done by calling the "clone()" system call directly, you | |
241 | * do not have enough call-clobbered registers to hold all | |
242 | * the information you need. | |
243 | */ | |
244 | int sys_vfork(struct pt_regs *regs) | |
245 | { | |
246 | return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0, | |
247 | NULL, NULL); | |
248 | } | |
249 | ||
250 | ||
00dba564 TG |
251 | /* |
252 | * Idle related variables and functions | |
253 | */ | |
254 | unsigned long boot_option_idle_override = 0; | |
255 | EXPORT_SYMBOL(boot_option_idle_override); | |
256 | ||
257 | /* | |
258 | * Powermanagement idle function, if any.. | |
259 | */ | |
260 | void (*pm_idle)(void); | |
261 | EXPORT_SYMBOL(pm_idle); | |
262 | ||
263 | #ifdef CONFIG_X86_32 | |
264 | /* | |
265 | * This halt magic was a workaround for ancient floppy DMA | |
266 | * wreckage. It should be safe to remove. | |
267 | */ | |
268 | static int hlt_counter; | |
269 | void disable_hlt(void) | |
270 | { | |
271 | hlt_counter++; | |
272 | } | |
273 | EXPORT_SYMBOL(disable_hlt); | |
274 | ||
275 | void enable_hlt(void) | |
276 | { | |
277 | hlt_counter--; | |
278 | } | |
279 | EXPORT_SYMBOL(enable_hlt); | |
280 | ||
281 | static inline int hlt_use_halt(void) | |
282 | { | |
283 | return (!hlt_counter && boot_cpu_data.hlt_works_ok); | |
284 | } | |
285 | #else | |
286 | static inline int hlt_use_halt(void) | |
287 | { | |
288 | return 1; | |
289 | } | |
290 | #endif | |
291 | ||
292 | /* | |
293 | * We use this if we don't have any better | |
294 | * idle routine.. | |
295 | */ | |
296 | void default_idle(void) | |
297 | { | |
298 | if (hlt_use_halt()) { | |
61613521 | 299 | trace_power_start(POWER_CSTATE, 1); |
00dba564 TG |
300 | current_thread_info()->status &= ~TS_POLLING; |
301 | /* | |
302 | * TS_POLLING-cleared state must be visible before we | |
303 | * test NEED_RESCHED: | |
304 | */ | |
305 | smp_mb(); | |
306 | ||
307 | if (!need_resched()) | |
308 | safe_halt(); /* enables interrupts racelessly */ | |
309 | else | |
310 | local_irq_enable(); | |
311 | current_thread_info()->status |= TS_POLLING; | |
312 | } else { | |
313 | local_irq_enable(); | |
314 | /* loop is done by the caller */ | |
315 | cpu_relax(); | |
316 | } | |
317 | } | |
318 | #ifdef CONFIG_APM_MODULE | |
319 | EXPORT_SYMBOL(default_idle); | |
320 | #endif | |
321 | ||
d3ec5cae IV |
322 | void stop_this_cpu(void *dummy) |
323 | { | |
324 | local_irq_disable(); | |
325 | /* | |
326 | * Remove this CPU: | |
327 | */ | |
4f062896 | 328 | set_cpu_online(smp_processor_id(), false); |
d3ec5cae IV |
329 | disable_local_APIC(); |
330 | ||
331 | for (;;) { | |
332 | if (hlt_works(smp_processor_id())) | |
333 | halt(); | |
334 | } | |
335 | } | |
336 | ||
7f424a8b PZ |
337 | static void do_nothing(void *unused) |
338 | { | |
339 | } | |
340 | ||
341 | /* | |
342 | * cpu_idle_wait - Used to ensure that all the CPUs discard old value of | |
343 | * pm_idle and update to new pm_idle value. Required while changing pm_idle | |
344 | * handler on SMP systems. | |
345 | * | |
346 | * Caller must have changed pm_idle to the new value before the call. Old | |
347 | * pm_idle value will not be used by any CPU after the return of this function. | |
348 | */ | |
349 | void cpu_idle_wait(void) | |
350 | { | |
351 | smp_mb(); | |
352 | /* kick all the CPUs so that they exit out of pm_idle */ | |
127a237a | 353 | smp_call_function(do_nothing, NULL, 1); |
7f424a8b PZ |
354 | } |
355 | EXPORT_SYMBOL_GPL(cpu_idle_wait); | |
356 | ||
357 | /* | |
358 | * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, | |
359 | * which can obviate IPI to trigger checking of need_resched. | |
360 | * We execute MONITOR against need_resched and enter optimized wait state | |
361 | * through MWAIT. Whenever someone changes need_resched, we would be woken | |
362 | * up from MWAIT (without an IPI). | |
363 | * | |
364 | * New with Core Duo processors, MWAIT can take some hints based on CPU | |
365 | * capability. | |
366 | */ | |
367 | void mwait_idle_with_hints(unsigned long ax, unsigned long cx) | |
368 | { | |
61613521 | 369 | trace_power_start(POWER_CSTATE, (ax>>4)+1); |
7f424a8b | 370 | if (!need_resched()) { |
e736ad54 PV |
371 | if (cpu_has(¤t_cpu_data, X86_FEATURE_CLFLUSH_MONITOR)) |
372 | clflush((void *)¤t_thread_info()->flags); | |
373 | ||
7f424a8b PZ |
374 | __monitor((void *)¤t_thread_info()->flags, 0, 0); |
375 | smp_mb(); | |
376 | if (!need_resched()) | |
377 | __mwait(ax, cx); | |
378 | } | |
379 | } | |
380 | ||
381 | /* Default MONITOR/MWAIT with no hints, used for default C1 state */ | |
382 | static void mwait_idle(void) | |
383 | { | |
384 | if (!need_resched()) { | |
61613521 | 385 | trace_power_start(POWER_CSTATE, 1); |
e736ad54 PV |
386 | if (cpu_has(¤t_cpu_data, X86_FEATURE_CLFLUSH_MONITOR)) |
387 | clflush((void *)¤t_thread_info()->flags); | |
388 | ||
7f424a8b PZ |
389 | __monitor((void *)¤t_thread_info()->flags, 0, 0); |
390 | smp_mb(); | |
391 | if (!need_resched()) | |
392 | __sti_mwait(0, 0); | |
393 | else | |
394 | local_irq_enable(); | |
395 | } else | |
396 | local_irq_enable(); | |
397 | } | |
398 | ||
7f424a8b PZ |
399 | /* |
400 | * On SMP it's slightly faster (but much more power-consuming!) | |
401 | * to poll the ->work.need_resched flag instead of waiting for the | |
402 | * cross-CPU IPI to arrive. Use this option with caution. | |
403 | */ | |
404 | static void poll_idle(void) | |
405 | { | |
61613521 | 406 | trace_power_start(POWER_CSTATE, 0); |
7f424a8b | 407 | local_irq_enable(); |
2c7e9fd4 JK |
408 | while (!need_resched()) |
409 | cpu_relax(); | |
61613521 | 410 | trace_power_end(0); |
7f424a8b PZ |
411 | } |
412 | ||
e9623b35 TG |
413 | /* |
414 | * mwait selection logic: | |
415 | * | |
416 | * It depends on the CPU. For AMD CPUs that support MWAIT this is | |
417 | * wrong. Family 0x10 and 0x11 CPUs will enter C1 on HLT. Powersavings | |
418 | * then depend on a clock divisor and current Pstate of the core. If | |
419 | * all cores of a processor are in halt state (C1) the processor can | |
420 | * enter the C1E (C1 enhanced) state. If mwait is used this will never | |
421 | * happen. | |
422 | * | |
423 | * idle=mwait overrides this decision and forces the usage of mwait. | |
424 | */ | |
08ad8afa | 425 | static int __cpuinitdata force_mwait; |
09fd4b4e TG |
426 | |
427 | #define MWAIT_INFO 0x05 | |
428 | #define MWAIT_ECX_EXTENDED_INFO 0x01 | |
429 | #define MWAIT_EDX_C1 0xf0 | |
430 | ||
e9623b35 TG |
431 | static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c) |
432 | { | |
09fd4b4e TG |
433 | u32 eax, ebx, ecx, edx; |
434 | ||
e9623b35 TG |
435 | if (force_mwait) |
436 | return 1; | |
437 | ||
09fd4b4e TG |
438 | if (c->cpuid_level < MWAIT_INFO) |
439 | return 0; | |
440 | ||
441 | cpuid(MWAIT_INFO, &eax, &ebx, &ecx, &edx); | |
442 | /* Check, whether EDX has extended info about MWAIT */ | |
443 | if (!(ecx & MWAIT_ECX_EXTENDED_INFO)) | |
444 | return 1; | |
445 | ||
446 | /* | |
447 | * edx enumeratios MONITOR/MWAIT extensions. Check, whether | |
448 | * C1 supports MWAIT | |
449 | */ | |
450 | return (edx & MWAIT_EDX_C1); | |
e9623b35 TG |
451 | } |
452 | ||
aa276e1c TG |
453 | /* |
454 | * Check for AMD CPUs, which have potentially C1E support | |
455 | */ | |
456 | static int __cpuinit check_c1e_idle(const struct cpuinfo_x86 *c) | |
457 | { | |
458 | if (c->x86_vendor != X86_VENDOR_AMD) | |
459 | return 0; | |
460 | ||
461 | if (c->x86 < 0x0F) | |
462 | return 0; | |
463 | ||
464 | /* Family 0x0f models < rev F do not have C1E */ | |
465 | if (c->x86 == 0x0f && c->x86_model < 0x40) | |
466 | return 0; | |
467 | ||
468 | return 1; | |
469 | } | |
470 | ||
bc9b83dd | 471 | static cpumask_var_t c1e_mask; |
4faac97d TG |
472 | static int c1e_detected; |
473 | ||
474 | void c1e_remove_cpu(int cpu) | |
475 | { | |
30e1e6d1 RR |
476 | if (c1e_mask != NULL) |
477 | cpumask_clear_cpu(cpu, c1e_mask); | |
4faac97d TG |
478 | } |
479 | ||
aa276e1c TG |
480 | /* |
481 | * C1E aware idle routine. We check for C1E active in the interrupt | |
482 | * pending message MSR. If we detect C1E, then we handle it the same | |
483 | * way as C3 power states (local apic timer and TSC stop) | |
484 | */ | |
485 | static void c1e_idle(void) | |
486 | { | |
aa276e1c TG |
487 | if (need_resched()) |
488 | return; | |
489 | ||
490 | if (!c1e_detected) { | |
491 | u32 lo, hi; | |
492 | ||
493 | rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi); | |
494 | if (lo & K8_INTP_C1E_ACTIVE_MASK) { | |
495 | c1e_detected = 1; | |
40fb1715 | 496 | if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) |
09bfeea1 AH |
497 | mark_tsc_unstable("TSC halt in AMD C1E"); |
498 | printk(KERN_INFO "System has AMD C1E enabled\n"); | |
a8d68290 | 499 | set_cpu_cap(&boot_cpu_data, X86_FEATURE_AMDC1E); |
aa276e1c TG |
500 | } |
501 | } | |
502 | ||
503 | if (c1e_detected) { | |
504 | int cpu = smp_processor_id(); | |
505 | ||
bc9b83dd RR |
506 | if (!cpumask_test_cpu(cpu, c1e_mask)) { |
507 | cpumask_set_cpu(cpu, c1e_mask); | |
0beefa20 | 508 | /* |
f833bab8 | 509 | * Force broadcast so ACPI can not interfere. |
0beefa20 | 510 | */ |
aa276e1c TG |
511 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_FORCE, |
512 | &cpu); | |
513 | printk(KERN_INFO "Switch to broadcast mode on CPU%d\n", | |
514 | cpu); | |
515 | } | |
516 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); | |
0beefa20 | 517 | |
aa276e1c | 518 | default_idle(); |
0beefa20 TG |
519 | |
520 | /* | |
521 | * The switch back from broadcast mode needs to be | |
522 | * called with interrupts disabled. | |
523 | */ | |
524 | local_irq_disable(); | |
525 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); | |
526 | local_irq_enable(); | |
aa276e1c TG |
527 | } else |
528 | default_idle(); | |
529 | } | |
530 | ||
7f424a8b PZ |
531 | void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) |
532 | { | |
3e5095d1 | 533 | #ifdef CONFIG_SMP |
7f424a8b PZ |
534 | if (pm_idle == poll_idle && smp_num_siblings > 1) { |
535 | printk(KERN_WARNING "WARNING: polling idle and HT enabled," | |
536 | " performance may degrade.\n"); | |
537 | } | |
538 | #endif | |
6ddd2a27 TG |
539 | if (pm_idle) |
540 | return; | |
541 | ||
e9623b35 | 542 | if (cpu_has(c, X86_FEATURE_MWAIT) && mwait_usable(c)) { |
7f424a8b | 543 | /* |
7f424a8b PZ |
544 | * One CPU supports mwait => All CPUs supports mwait |
545 | */ | |
6ddd2a27 TG |
546 | printk(KERN_INFO "using mwait in idle threads.\n"); |
547 | pm_idle = mwait_idle; | |
aa276e1c TG |
548 | } else if (check_c1e_idle(c)) { |
549 | printk(KERN_INFO "using C1E aware idle routine\n"); | |
550 | pm_idle = c1e_idle; | |
6ddd2a27 TG |
551 | } else |
552 | pm_idle = default_idle; | |
7f424a8b PZ |
553 | } |
554 | ||
30e1e6d1 RR |
555 | void __init init_c1e_mask(void) |
556 | { | |
557 | /* If we're using c1e_idle, we need to allocate c1e_mask. */ | |
79f55997 LZ |
558 | if (pm_idle == c1e_idle) |
559 | zalloc_cpumask_var(&c1e_mask, GFP_KERNEL); | |
30e1e6d1 RR |
560 | } |
561 | ||
7f424a8b PZ |
562 | static int __init idle_setup(char *str) |
563 | { | |
ab6bc3e3 CG |
564 | if (!str) |
565 | return -EINVAL; | |
566 | ||
7f424a8b PZ |
567 | if (!strcmp(str, "poll")) { |
568 | printk("using polling idle threads.\n"); | |
569 | pm_idle = poll_idle; | |
570 | } else if (!strcmp(str, "mwait")) | |
571 | force_mwait = 1; | |
c1e3b377 ZY |
572 | else if (!strcmp(str, "halt")) { |
573 | /* | |
574 | * When the boot option of idle=halt is added, halt is | |
575 | * forced to be used for CPU idle. In such case CPU C2/C3 | |
576 | * won't be used again. | |
577 | * To continue to load the CPU idle driver, don't touch | |
578 | * the boot_option_idle_override. | |
579 | */ | |
580 | pm_idle = default_idle; | |
581 | idle_halt = 1; | |
582 | return 0; | |
da5e09a1 ZY |
583 | } else if (!strcmp(str, "nomwait")) { |
584 | /* | |
585 | * If the boot option of "idle=nomwait" is added, | |
586 | * it means that mwait will be disabled for CPU C2/C3 | |
587 | * states. In such case it won't touch the variable | |
588 | * of boot_option_idle_override. | |
589 | */ | |
590 | idle_nomwait = 1; | |
591 | return 0; | |
c1e3b377 | 592 | } else |
7f424a8b PZ |
593 | return -1; |
594 | ||
595 | boot_option_idle_override = 1; | |
596 | return 0; | |
597 | } | |
598 | early_param("idle", idle_setup); | |
599 | ||
9d62dcdf AW |
600 | unsigned long arch_align_stack(unsigned long sp) |
601 | { | |
602 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) | |
603 | sp -= get_random_int() % 8192; | |
604 | return sp & ~0xf; | |
605 | } | |
606 | ||
607 | unsigned long arch_randomize_brk(struct mm_struct *mm) | |
608 | { | |
609 | unsigned long range_end = mm->brk + 0x02000000; | |
610 | return randomize_range(mm->brk, range_end, 0) ? : mm->brk; | |
611 | } | |
612 |