idle: Implement set/clr functions for need_resched poll
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / init / main.c
CommitLineData
1da177e4
LT
1/*
2 * linux/init/main.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * GK 2/5/95 - Changed to support mounting root fs via NFS
7 * Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
8 * Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
9 * Simplified starting of init: Michael A. Griffith <grif@acm.org>
10 */
11
1da177e4
LT
12#include <linux/types.h>
13#include <linux/module.h>
14#include <linux/proc_fs.h>
1da177e4
LT
15#include <linux/kernel.h>
16#include <linux/syscalls.h>
9b5609fd 17#include <linux/stackprotector.h>
1da177e4
LT
18#include <linux/string.h>
19#include <linux/ctype.h>
20#include <linux/delay.h>
1da177e4
LT
21#include <linux/ioport.h>
22#include <linux/init.h>
1da177e4 23#include <linux/initrd.h>
1da177e4 24#include <linux/bootmem.h>
4a7a16dc 25#include <linux/acpi.h>
1da177e4 26#include <linux/tty.h>
1da177e4
LT
27#include <linux/percpu.h>
28#include <linux/kmod.h>
db64fe02 29#include <linux/vmalloc.h>
1da177e4 30#include <linux/kernel_stat.h>
d7cd5611 31#include <linux/start_kernel.h>
1da177e4 32#include <linux/security.h>
3d442233 33#include <linux/smp.h>
1da177e4
LT
34#include <linux/profile.h>
35#include <linux/rcupdate.h>
36#include <linux/moduleparam.h>
37#include <linux/kallsyms.h>
38#include <linux/writeback.h>
39#include <linux/cpu.h>
40#include <linux/cpuset.h>
ddbcc7e8 41#include <linux/cgroup.h>
1da177e4 42#include <linux/efi.h>
906568c9 43#include <linux/tick.h>
6168a702 44#include <linux/interrupt.h>
c757249a 45#include <linux/taskstats_kern.h>
ca74e92b 46#include <linux/delayacct.h>
1da177e4
LT
47#include <linux/unistd.h>
48#include <linux/rmap.h>
49#include <linux/mempolicy.h>
50#include <linux/key.h>
b6cd0b77 51#include <linux/buffer_head.h>
94b6da5a 52#include <linux/page_cgroup.h>
9a11b49a 53#include <linux/debug_locks.h>
3ac7fe5a 54#include <linux/debugobjects.h>
fbb9ce95 55#include <linux/lockdep.h>
3c7b4e6b 56#include <linux/kmemleak.h>
84d73786 57#include <linux/pid_namespace.h>
1f21782e 58#include <linux/device.h>
73c27992 59#include <linux/kthread.h>
e6fe6649 60#include <linux/sched.h>
a1c9eea9 61#include <linux/signal.h>
199f0ca5 62#include <linux/idr.h>
0b4b3827 63#include <linux/kgdb.h>
68bf21aa 64#include <linux/ftrace.h>
22a9d645 65#include <linux/async.h>
dfec072e 66#include <linux/kmemcheck.h>
6ae6996a 67#include <linux/sfi.h>
2b2af54a 68#include <linux/shmem_fs.h>
5a0e3ad6 69#include <linux/slab.h>
24a24bb6 70#include <linux/perf_event.h>
4a9d4b02 71#include <linux/file.h>
a74fb73c 72#include <linux/ptrace.h>
bb813f4c
TH
73#include <linux/blkdev.h>
74#include <linux/elevator.h>
1da177e4
LT
75
76#include <asm/io.h>
77#include <asm/bugs.h>
78#include <asm/setup.h>
a940199f 79#include <asm/sections.h>
37b73c82 80#include <asm/cacheflush.h>
1da177e4 81
1da177e4
LT
82#ifdef CONFIG_X86_LOCAL_APIC
83#include <asm/smp.h>
84#endif
85
aae5f662 86static int kernel_init(void *);
1da177e4
LT
87
88extern void init_IRQ(void);
1da177e4
LT
89extern void fork_init(unsigned long);
90extern void mca_init(void);
91extern void sbus_init(void);
1da177e4 92extern void radix_tree_init(void);
37b73c82
AV
93#ifndef CONFIG_DEBUG_RODATA
94static inline void mark_rodata_ro(void) { }
95#endif
1da177e4
LT
96
97#ifdef CONFIG_TC
98extern void tc_init(void);
99#endif
100
2ce802f6
TH
101/*
102 * Debug helper: via this flag we know that we are in 'early bootup code'
103 * where only the boot processor is running with IRQ disabled. This means
104 * two things - IRQ must not be enabled before the flag is cleared and some
105 * operations which are not allowed with IRQ disabled are allowed while the
106 * flag is set.
107 */
108bool early_boot_irqs_disabled __read_mostly;
109
a6826048 110enum system_states system_state __read_mostly;
1da177e4
LT
111EXPORT_SYMBOL(system_state);
112
113/*
114 * Boot command-line arguments
115 */
116#define MAX_INIT_ARGS CONFIG_INIT_ENV_ARG_LIMIT
117#define MAX_INIT_ENVS CONFIG_INIT_ENV_ARG_LIMIT
118
119extern void time_init(void);
120/* Default late time init is NULL. archs can override this later. */
d2e3192b 121void (*__initdata late_time_init)(void);
1da177e4
LT
122extern void softirq_init(void);
123
30d7e0d4
ABL
124/* Untouched command line saved by arch-specific code. */
125char __initdata boot_command_line[COMMAND_LINE_SIZE];
126/* Untouched saved command line (eg. for /proc) */
127char *saved_command_line;
128/* Command line for parameter parsing */
129static char *static_command_line;
1da177e4
LT
130
131static char *execute_command;
ffdfc409 132static char *ramdisk_execute_command;
1da177e4 133
8b3b2955
JB
134/*
135 * If set, this is an indication to the drivers that reset the underlying
136 * device before going ahead with the initialization otherwise driver might
137 * rely on the BIOS and skip the reset operation.
138 *
139 * This is useful if kernel is booting in an unreliable environment.
140 * For ex. kdump situaiton where previous kernel has crashed, BIOS has been
141 * skipped and devices will be in unknown state.
142 */
143unsigned int reset_devices;
144EXPORT_SYMBOL(reset_devices);
1da177e4 145
7e96287d
VG
146static int __init set_reset_devices(char *str)
147{
148 reset_devices = 1;
149 return 1;
150}
151
152__setup("reset_devices", set_reset_devices);
153
d7627467
DH
154static const char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
155const char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
1da177e4
LT
156static const char *panic_later, *panic_param;
157
914dcaa8 158extern const struct obs_kernel_param __setup_start[], __setup_end[];
1da177e4
LT
159
160static int __init obsolete_checksetup(char *line)
161{
914dcaa8 162 const struct obs_kernel_param *p;
33df0d19 163 int had_early_param = 0;
1da177e4
LT
164
165 p = __setup_start;
166 do {
167 int n = strlen(p->str);
b1e4d20c 168 if (parameqn(line, p->str, n)) {
1da177e4 169 if (p->early) {
33df0d19
RR
170 /* Already done in parse_early_param?
171 * (Needs exact match on param part).
172 * Keep iterating, as we can have early
173 * params and __setups of same names 8( */
1da177e4 174 if (line[n] == '\0' || line[n] == '=')
33df0d19 175 had_early_param = 1;
1da177e4
LT
176 } else if (!p->setup_func) {
177 printk(KERN_WARNING "Parameter %s is obsolete,"
178 " ignored\n", p->str);
179 return 1;
180 } else if (p->setup_func(line + n))
181 return 1;
182 }
183 p++;
184 } while (p < __setup_end);
33df0d19
RR
185
186 return had_early_param;
1da177e4
LT
187}
188
189/*
190 * This should be approx 2 Bo*oMips to start (note initial shift), and will
191 * still work even if initially too large, it will just take slightly longer
192 */
193unsigned long loops_per_jiffy = (1<<12);
194
195EXPORT_SYMBOL(loops_per_jiffy);
196
197static int __init debug_kernel(char *str)
198{
1da177e4 199 console_loglevel = 10;
f6f21c81 200 return 0;
1da177e4
LT
201}
202
203static int __init quiet_kernel(char *str)
204{
1da177e4 205 console_loglevel = 4;
f6f21c81 206 return 0;
1da177e4
LT
207}
208
f6f21c81
YL
209early_param("debug", debug_kernel);
210early_param("quiet", quiet_kernel);
1da177e4
LT
211
212static int __init loglevel(char *str)
213{
808bf29b
AS
214 int newlevel;
215
216 /*
217 * Only update loglevel value when a correct setting was passed,
218 * to prevent blind crashes (when loglevel being set to 0) that
219 * are quite hard to debug
220 */
221 if (get_option(&str, &newlevel)) {
222 console_loglevel = newlevel;
223 return 0;
224 }
225
226 return -EINVAL;
1da177e4
LT
227}
228
f6f21c81 229early_param("loglevel", loglevel);
1da177e4 230
a99cd112 231/* Change NUL term back to "=", to make "param" the whole string. */
eb157427 232static int __init repair_env_string(char *param, char *val, const char *unused)
1da177e4 233{
1da177e4
LT
234 if (val) {
235 /* param=val or param="val"? */
236 if (val == param+strlen(param)+1)
237 val[-1] = '=';
238 else if (val == param+strlen(param)+2) {
239 val[-2] = '=';
240 memmove(val-1, val, strlen(val)+1);
241 val--;
242 } else
243 BUG();
244 }
a99cd112
CM
245 return 0;
246}
247
248/*
249 * Unknown boot options get handed to init, unless they look like
250 * unused parameters (modprobe will find them in /proc/cmdline).
251 */
eb157427 252static int __init unknown_bootoption(char *param, char *val, const char *unused)
a99cd112 253{
eb157427 254 repair_env_string(param, val, unused);
1da177e4
LT
255
256 /* Handle obsolete-style parameters */
257 if (obsolete_checksetup(param))
258 return 0;
259
f066a4f6
RR
260 /* Unused module parameter. */
261 if (strchr(param, '.') && (!val || strchr(param, '.') < val))
1da177e4 262 return 0;
1da177e4
LT
263
264 if (panic_later)
265 return 0;
266
267 if (val) {
268 /* Environment option */
269 unsigned int i;
270 for (i = 0; envp_init[i]; i++) {
271 if (i == MAX_INIT_ENVS) {
272 panic_later = "Too many boot env vars at `%s'";
273 panic_param = param;
274 }
275 if (!strncmp(param, envp_init[i], val - param))
276 break;
277 }
278 envp_init[i] = param;
279 } else {
280 /* Command line option */
281 unsigned int i;
282 for (i = 0; argv_init[i]; i++) {
283 if (i == MAX_INIT_ARGS) {
284 panic_later = "Too many boot init vars at `%s'";
285 panic_param = param;
286 }
287 }
288 argv_init[i] = param;
289 }
290 return 0;
291}
292
293static int __init init_setup(char *str)
294{
295 unsigned int i;
296
297 execute_command = str;
298 /*
299 * In case LILO is going to boot us with default command line,
300 * it prepends "auto" before the whole cmdline which makes
301 * the shell think it should execute a script with such name.
302 * So we ignore all arguments entered _before_ init=... [MJ]
303 */
304 for (i = 1; i < MAX_INIT_ARGS; i++)
305 argv_init[i] = NULL;
306 return 1;
307}
308__setup("init=", init_setup);
309
ffdfc409
OJ
310static int __init rdinit_setup(char *str)
311{
312 unsigned int i;
313
314 ramdisk_execute_command = str;
315 /* See "auto" comment in init_setup */
316 for (i = 1; i < MAX_INIT_ARGS; i++)
317 argv_init[i] = NULL;
318 return 1;
319}
320__setup("rdinit=", rdinit_setup);
321
1da177e4 322#ifndef CONFIG_SMP
34db18a0 323static const unsigned int setup_max_cpus = NR_CPUS;
1da177e4
LT
324#ifdef CONFIG_X86_LOCAL_APIC
325static void __init smp_init(void)
326{
327 APIC_init_uniprocessor();
328}
329#else
330#define smp_init() do { } while (0)
331#endif
332
e0982e90 333static inline void setup_nr_cpu_ids(void) { }
1da177e4 334static inline void smp_prepare_cpus(unsigned int maxcpus) { }
1da177e4
LT
335#endif
336
30d7e0d4
ABL
337/*
338 * We need to store the untouched command line for future reference.
339 * We also need to store the touched command line since the parameter
340 * parsing is performed in place, and we should allow a component to
341 * store reference of name/value for future reference.
342 */
343static void __init setup_command_line(char *command_line)
344{
345 saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
346 static_command_line = alloc_bootmem(strlen (command_line)+1);
347 strcpy (saved_command_line, boot_command_line);
348 strcpy (static_command_line, command_line);
349}
350
1da177e4
LT
351/*
352 * We need to finalize in a non-__init function or else race conditions
353 * between the root thread and the init thread may cause start_kernel to
354 * be reaped by free_initmem before the root thread has proceeded to
355 * cpu_idle.
356 *
357 * gcc-3.4 accidentally inlines this function, so use noinline.
358 */
359
b433c3d4
PZ
360static __initdata DECLARE_COMPLETION(kthreadd_done);
361
f99ebf0a 362static noinline void __init_refok rest_init(void)
1da177e4 363{
73c27992
EB
364 int pid;
365
7db905e6 366 rcu_scheduler_starting();
b433c3d4 367 /*
97158569 368 * We need to spawn init first so that it obtains pid 1, however
b433c3d4
PZ
369 * the init task will end up wanting to create kthreads, which, if
370 * we schedule it before we create kthreadd, will OOPS.
371 */
aae5f662 372 kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
1da177e4 373 numa_default_policy();
73c27992 374 pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
d11c563d 375 rcu_read_lock();
5cd20455 376 kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
d11c563d 377 rcu_read_unlock();
b433c3d4 378 complete(&kthreadd_done);
f340c0d1
IM
379
380 /*
381 * The boot idle thread must execute schedule()
1df21055 382 * at least once to get things moving:
f340c0d1 383 */
1df21055 384 init_idle_bootup_task(current);
bd2f5536 385 schedule_preempt_disabled();
5bfb5d69 386 /* Call into cpu_idle with preempt disabled */
1da177e4 387 cpu_idle();
1df21055 388}
1da177e4
LT
389
390/* Check for early params. */
9fb48c74 391static int __init do_early_param(char *param, char *val, const char *unused)
1da177e4 392{
914dcaa8 393 const struct obs_kernel_param *p;
1da177e4
LT
394
395 for (p = __setup_start; p < __setup_end; p++) {
b1e4d20c 396 if ((p->early && parameq(param, p->str)) ||
18a8bd94
YL
397 (strcmp(param, "console") == 0 &&
398 strcmp(p->str, "earlycon") == 0)
399 ) {
1da177e4
LT
400 if (p->setup_func(val) != 0)
401 printk(KERN_WARNING
402 "Malformed early option '%s'\n", param);
403 }
404 }
405 /* We accept everything at this stage. */
406 return 0;
407}
408
13977091
MD
409void __init parse_early_options(char *cmdline)
410{
026cee00 411 parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
13977091
MD
412}
413
1da177e4
LT
414/* Arch code calls this early on, or if not, just before other parsing. */
415void __init parse_early_param(void)
416{
417 static __initdata int done = 0;
418 static __initdata char tmp_cmdline[COMMAND_LINE_SIZE];
419
420 if (done)
421 return;
422
423 /* All fall through to do_early_param. */
30d7e0d4 424 strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
13977091 425 parse_early_options(tmp_cmdline);
1da177e4
LT
426 done = 1;
427}
428
429/*
430 * Activate the first processor.
431 */
432
44fd2299
SS
433static void __init boot_cpu_init(void)
434{
435 int cpu = smp_processor_id();
436 /* Mark the boot cpu "present", "online" etc for SMP and UP case */
915441b6 437 set_cpu_online(cpu, true);
933b0618 438 set_cpu_active(cpu, true);
915441b6
RR
439 set_cpu_present(cpu, true);
440 set_cpu_possible(cpu, true);
44fd2299
SS
441}
442
839ad62e 443void __init __weak smp_setup_processor_id(void)
033ab7f8
AM
444{
445}
446
eded09cc 447# if THREAD_SIZE >= PAGE_SIZE
8c9843e5
BH
448void __init __weak thread_info_cache_init(void)
449{
450}
eded09cc 451#endif
8c9843e5 452
444f478f
PE
453/*
454 * Set up kernel memory allocators
455 */
456static void __init mm_init(void)
457{
ca371c0d 458 /*
7fa87ce7
JC
459 * page_cgroup requires contiguous pages,
460 * bigger than MAX_ORDER unless SPARSEMEM.
ca371c0d
KH
461 */
462 page_cgroup_init_flatmem();
444f478f
PE
463 mem_init();
464 kmem_cache_init();
099a19d9 465 percpu_init_late();
c868d550 466 pgtable_cache_init();
444f478f
PE
467 vmalloc_init();
468}
469
1da177e4
LT
470asmlinkage void __init start_kernel(void)
471{
472 char * command_line;
914dcaa8 473 extern const struct kernel_param __start___param[], __stop___param[];
033ab7f8 474
fbb9ce95
IM
475 /*
476 * Need to run as early as possible, to initialize the
477 * lockdep hash:
478 */
479 lockdep_init();
73839c5b 480 smp_setup_processor_id();
3ac7fe5a 481 debug_objects_early_init();
42059429
IM
482
483 /*
484 * Set up the the initial canary ASAP:
485 */
486 boot_init_stack_canary();
487
ddbcc7e8 488 cgroup_init_early();
fbb9ce95
IM
489
490 local_irq_disable();
2ce802f6 491 early_boot_irqs_disabled = true;
fbb9ce95 492
1da177e4
LT
493/*
494 * Interrupts are still disabled. Do necessary setups, then
495 * enable them
496 */
906568c9 497 tick_init();
44fd2299 498 boot_cpu_init();
1da177e4 499 page_address_init();
657cafa6 500 printk(KERN_NOTICE "%s", linux_banner);
1da177e4 501 setup_arch(&command_line);
cf475ad2 502 mm_init_owner(&init_mm, &init_task);
6345d24d 503 mm_init_cpumask(&init_mm);
30d7e0d4 504 setup_command_line(command_line);
e0982e90 505 setup_nr_cpu_ids();
d6647bdf 506 setup_per_cpu_areas();
44fd2299 507 smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */
1da177e4 508
9adb62a5 509 build_all_zonelists(NULL, NULL);
83b519e8
PE
510 page_alloc_init();
511
512 printk(KERN_NOTICE "Kernel command line: %s\n", boot_command_line);
513 parse_early_param();
514 parse_args("Booting kernel", static_command_line, __start___param,
515 __stop___param - __start___param,
ae82fdb1 516 -1, -1, &unknown_bootoption);
97ce2c88
JF
517
518 jump_label_init();
519
83b519e8
PE
520 /*
521 * These use large bootmem allocations and must precede
522 * kmem_cache_init()
523 */
162a7e75 524 setup_log_buf(0);
83b519e8 525 pidhash_init();
83b519e8
PE
526 vfs_caches_init_early();
527 sort_main_extable();
528 trap_init();
444f478f 529 mm_init();
de03c72c 530
1da177e4
LT
531 /*
532 * Set up the scheduler prior starting any interrupts (such as the
533 * timer interrupt). Full topology setup happens at smp_init()
534 * time - but meanwhile we still have a functioning scheduler.
535 */
536 sched_init();
537 /*
538 * Disable preemption - early bootup scheduling is extremely
539 * fragile until we cpu_idle() for the first time.
540 */
541 preempt_disable();
c4a68306
AB
542 if (!irqs_disabled()) {
543 printk(KERN_WARNING "start_kernel(): bug: interrupts were "
544 "enabled *very* early, fixing it\n");
545 local_irq_disable();
546 }
9f58a205 547 idr_init_cache();
24a24bb6 548 perf_event_init();
1da177e4 549 rcu_init();
773e3eb7 550 radix_tree_init();
0b8f1efa
YL
551 /* init some links before init_ISA_irqs() */
552 early_irq_init();
1da177e4 553 init_IRQ();
1da177e4 554 init_timers();
c0a31329 555 hrtimers_init();
1da177e4 556 softirq_init();
ad596171 557 timekeeping_init();
88fecaa2 558 time_init();
93e02814 559 profile_init();
d8ad7d11 560 call_function_init();
93e02814 561 if (!irqs_disabled())
24d431d0
RL
562 printk(KERN_CRIT "start_kernel(): bug: interrupts were "
563 "enabled early\n");
2ce802f6 564 early_boot_irqs_disabled = false;
93e02814 565 local_irq_enable();
dcce284a 566
7e85ee0c 567 kmem_cache_init_late();
1da177e4
LT
568
569 /*
570 * HACK ALERT! This is early. We're enabling the console before
571 * we've done PCI setups etc, and console_init() must be aware of
572 * this. But we do want output early, in case something goes wrong.
573 */
574 console_init();
575 if (panic_later)
576 panic(panic_later, panic_param);
fbb9ce95
IM
577
578 lockdep_info();
579
9a11b49a
IM
580 /*
581 * Need to run this when irqs are enabled, because it wants
582 * to self-test [hard/soft]-irqs on/off lock inversion bugs
583 * too:
584 */
585 locking_selftest();
586
1da177e4
LT
587#ifdef CONFIG_BLK_DEV_INITRD
588 if (initrd_start && !initrd_below_start_ok &&
bd673c7c 589 page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
1da177e4 590 printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
fb6624eb 591 "disabling it.\n",
bd673c7c
GU
592 page_to_pfn(virt_to_page((void *)initrd_start)),
593 min_low_pfn);
1da177e4
LT
594 initrd_start = 0;
595 }
596#endif
94b6da5a 597 page_cgroup_init();
3ac7fe5a 598 debug_objects_mem_init();
9b090f2d 599 kmemleak_init();
e7c8d5c9 600 setup_per_cpu_pageset();
1da177e4
LT
601 numa_policy_init();
602 if (late_time_init)
603 late_time_init();
fa84e9ee 604 sched_clock_init();
1da177e4
LT
605 calibrate_delay();
606 pidmap_init();
1da177e4 607 anon_vma_init();
11520e5e 608#ifdef CONFIG_X86
83e68189 609 if (efi_enabled(EFI_RUNTIME_SERVICES))
11520e5e
LT
610 efi_enter_virtual_mode();
611#endif
8c9843e5 612 thread_info_cache_init();
d84f4f99 613 cred_init();
4481374c 614 fork_init(totalram_pages);
1da177e4
LT
615 proc_caches_init();
616 buffer_init();
1da177e4
LT
617 key_init();
618 security_init();
0b4b3827 619 dbg_late_init();
4481374c 620 vfs_caches_init(totalram_pages);
1da177e4
LT
621 signals_init();
622 /* rootfs populating might need page-writeback */
623 page_writeback_init();
624#ifdef CONFIG_PROC_FS
625 proc_root_init();
626#endif
ddbcc7e8 627 cgroup_init();
1da177e4 628 cpuset_init();
c757249a 629 taskstats_init_early();
ca74e92b 630 delayacct_init();
1da177e4
LT
631
632 check_bugs();
633
634 acpi_early_init(); /* before LAPIC and SMP init */
6ae6996a 635 sfi_init_late();
1da177e4 636
83e68189 637 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
2223af38 638 efi_late_init();
78510792 639 efi_free_boot_services();
2223af38 640 }
78510792 641
68bf21aa
SR
642 ftrace_init();
643
1da177e4
LT
644 /* Do the rest non-__init'ed, we're now alive */
645 rest_init();
646}
647
b99b87f7
PO
648/* Call all constructor functions linked into the kernel. */
649static void __init do_ctors(void)
650{
651#ifdef CONFIG_CONSTRUCTORS
196a15b4 652 ctor_fn_t *fn = (ctor_fn_t *) __ctors_start;
b99b87f7 653
196a15b4
HS
654 for (; fn < (ctor_fn_t *) __ctors_end; fn++)
655 (*fn)();
b99b87f7
PO
656#endif
657}
658
2329abfa 659bool initcall_debug;
d0ea3d7d 660core_param(initcall_debug, initcall_debug, bool, 0644);
1da177e4 661
4a683bf9 662static char msgbuf[64];
4a683bf9 663
e4461271 664static int __init_or_module do_one_initcall_debug(initcall_t fn)
1da177e4 665{
74239072 666 ktime_t calltime, delta, rettime;
30dbb20e
AW
667 unsigned long long duration;
668 int ret;
1da177e4 669
22c5c03b
KW
670 printk(KERN_DEBUG "calling %pF @ %i\n", fn, task_pid_nr(current));
671 calltime = ktime_get();
30dbb20e 672 ret = fn();
22c5c03b
KW
673 rettime = ktime_get();
674 delta = ktime_sub(rettime, calltime);
675 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
676 printk(KERN_DEBUG "initcall %pF returned %d after %lld usecs\n", fn,
677 ret, duration);
1da177e4 678
22c5c03b
KW
679 return ret;
680}
681
e4461271 682int __init_or_module do_one_initcall(initcall_t fn)
22c5c03b
KW
683{
684 int count = preempt_count();
685 int ret;
686
687 if (initcall_debug)
688 ret = do_one_initcall_debug(fn);
689 else
690 ret = fn();
8f0c45cd 691
e0df154f 692 msgbuf[0] = 0;
e662e1cf 693
30dbb20e
AW
694 if (ret && ret != -ENODEV && initcall_debug)
695 sprintf(msgbuf, "error code %d ", ret);
e662e1cf 696
e0df154f 697 if (preempt_count() != count) {
a76bfd0d 698 strlcat(msgbuf, "preemption imbalance ", sizeof(msgbuf));
e0df154f 699 preempt_count() = count;
1da177e4 700 }
e0df154f 701 if (irqs_disabled()) {
a76bfd0d 702 strlcat(msgbuf, "disabled interrupts ", sizeof(msgbuf));
e0df154f
LT
703 local_irq_enable();
704 }
705 if (msgbuf[0]) {
96d746c6 706 printk("initcall %pF returned with %s\n", fn, msgbuf);
e0df154f 707 }
59f9415f 708
30dbb20e 709 return ret;
e0df154f
LT
710}
711
712
026cee00
PM
713extern initcall_t __initcall_start[];
714extern initcall_t __initcall0_start[];
715extern initcall_t __initcall1_start[];
716extern initcall_t __initcall2_start[];
717extern initcall_t __initcall3_start[];
718extern initcall_t __initcall4_start[];
719extern initcall_t __initcall5_start[];
720extern initcall_t __initcall6_start[];
721extern initcall_t __initcall7_start[];
722extern initcall_t __initcall_end[];
723
724static initcall_t *initcall_levels[] __initdata = {
725 __initcall0_start,
726 __initcall1_start,
727 __initcall2_start,
728 __initcall3_start,
729 __initcall4_start,
730 __initcall5_start,
731 __initcall6_start,
732 __initcall7_start,
733 __initcall_end,
734};
735
96263d28 736/* Keep these in sync with initcalls in include/linux/init.h */
026cee00 737static char *initcall_level_names[] __initdata = {
9fb48c74
JC
738 "early",
739 "core",
740 "postcore",
741 "arch",
742 "subsys",
743 "fs",
744 "device",
745 "late",
026cee00
PM
746};
747
026cee00 748static void __init do_initcall_level(int level)
e0df154f 749{
026cee00 750 extern const struct kernel_param __start___param[], __stop___param[];
196a15b4 751 initcall_t *fn;
e0df154f 752
026cee00
PM
753 strcpy(static_command_line, saved_command_line);
754 parse_args(initcall_level_names[level],
755 static_command_line, __start___param,
756 __stop___param - __start___param,
757 level, level,
eb157427 758 &repair_env_string);
026cee00
PM
759
760 for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
196a15b4 761 do_one_initcall(*fn);
1da177e4
LT
762}
763
026cee00
PM
764static void __init do_initcalls(void)
765{
766 int level;
767
19efb72f 768 for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
026cee00
PM
769 do_initcall_level(level);
770}
771
1da177e4
LT
772/*
773 * Ok, the machine is now initialized. None of the devices
774 * have been touched yet, but the CPU subsystem is up and
775 * running, and memory and process management works.
776 *
777 * Now we can finally start doing some real work..
778 */
779static void __init do_basic_setup(void)
780{
759ee091 781 cpuset_init_smp();
1da177e4 782 usermodehelper_init();
41ffe5d5 783 shmem_init();
1da177e4 784 driver_init();
b04c3afb 785 init_irq_proc();
b99b87f7 786 do_ctors();
d5767c53 787 usermodehelper_enable();
b0f84374 788 do_initcalls();
1da177e4
LT
789}
790
7babe8db 791static void __init do_pre_smp_initcalls(void)
c2147a50 792{
196a15b4 793 initcall_t *fn;
c2147a50 794
026cee00 795 for (fn = __initcall_start; fn < __initcall0_start; fn++)
196a15b4 796 do_one_initcall(*fn);
c2147a50
EGM
797}
798
bb813f4c
TH
799/*
800 * This function requests modules which should be loaded by default and is
801 * called twice right after initrd is mounted and right before init is
802 * exec'd. If such modules are on either initrd or rootfs, they will be
803 * loaded before control is passed to userland.
804 */
805void __init load_default_modules(void)
806{
807 load_default_elevator_module();
808}
809
a74fb73c 810static int run_init_process(const char *init_filename)
1da177e4
LT
811{
812 argv_init[0] = init_filename;
ae903caa
AV
813 return do_execve(init_filename,
814 (const char __user *const __user *)argv_init,
815 (const char __user *const __user *)envp_init);
1da177e4
LT
816}
817
f80b0c90 818static noinline void __init kernel_init_freeable(void);
d6b21238
AV
819
820static int __ref kernel_init(void *unused)
ee5bfa64 821{
d6b21238 822 kernel_init_freeable();
22a9d645
AV
823 /* need to finish all async __init code before freeing the memory */
824 async_synchronize_full();
ee5bfa64 825 free_initmem();
ee5bfa64
VG
826 mark_rodata_ro();
827 system_state = SYSTEM_RUNNING;
828 numa_default_policy();
829
4a9d4b02 830 flush_delayed_fput();
fae5fa44 831
ee5bfa64 832 if (ramdisk_execute_command) {
a74fb73c
AV
833 if (!run_init_process(ramdisk_execute_command))
834 return 0;
ee5bfa64
VG
835 printk(KERN_WARNING "Failed to execute %s\n",
836 ramdisk_execute_command);
837 }
838
839 /*
840 * We try each of these until one succeeds.
841 *
842 * The Bourne shell can be used instead of init if we are
843 * trying to recover a really broken machine.
844 */
845 if (execute_command) {
a74fb73c
AV
846 if (!run_init_process(execute_command))
847 return 0;
ee5bfa64
VG
848 printk(KERN_WARNING "Failed to execute %s. Attempting "
849 "defaults...\n", execute_command);
850 }
a74fb73c
AV
851 if (!run_init_process("/sbin/init") ||
852 !run_init_process("/etc/init") ||
853 !run_init_process("/bin/init") ||
854 !run_init_process("/bin/sh"))
855 return 0;
ee5bfa64 856
9a85b8d6
AM
857 panic("No init found. Try passing init= option to kernel. "
858 "See Linux Documentation/init.txt for guidance.");
ee5bfa64
VG
859}
860
f80b0c90 861static noinline void __init kernel_init_freeable(void)
1da177e4 862{
b433c3d4
PZ
863 /*
864 * Wait until kthreadd is all set-up.
865 */
866 wait_for_completion(&kthreadd_done);
31a67102
LT
867
868 /* Now the scheduler is fully set up and can do blocking allocations */
869 gfp_allowed_mask = __GFP_BITS_MASK;
870
58568d2a
MX
871 /*
872 * init can allocate pages on any node
873 */
3c466d46 874 set_mems_allowed(node_states[N_MEMORY]);
1da177e4
LT
875 /*
876 * init can run on any cpu.
877 */
1a2142af 878 set_cpus_allowed_ptr(current, cpu_all_mask);
1da177e4 879
9ec52099
CLG
880 cad_pid = task_pid(current);
881
ca74a6f8 882 smp_prepare_cpus(setup_max_cpus);
1da177e4
LT
883
884 do_pre_smp_initcalls();
004417a6 885 lockup_detector_init();
1da177e4 886
1da177e4
LT
887 smp_init();
888 sched_init_smp();
889
1da177e4
LT
890 do_basic_setup();
891
2bd3a997
EB
892 /* Open the /dev/console on the rootfs, this should never fail */
893 if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
894 printk(KERN_WARNING "Warning: unable to open an initial console.\n");
895
896 (void) sys_dup(0);
897 (void) sys_dup(0);
1da177e4
LT
898 /*
899 * check if there is an early userspace init. If yes, let it do all
900 * the work
901 */
ffdfc409
OJ
902
903 if (!ramdisk_execute_command)
904 ramdisk_execute_command = "/init";
905
906 if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
907 ramdisk_execute_command = NULL;
1da177e4 908 prepare_namespace();
ffdfc409 909 }
1da177e4
LT
910
911 /*
912 * Ok, we have completed the initial bootup, and
913 * we're essentially up and running. Get rid of the
914 * initmem segments and start the user-mode stuff..
915 */
bb813f4c
TH
916
917 /* rootfs is available now, try loading default modules */
918 load_default_modules();
1da177e4 919}