/*
* linux/kernel/timer.c
*
- * Kernel internal timers, basic process system calls
+ * Kernel internal timers
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
cpu = smp_processor_id();
-#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
+#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
if (!pinned && get_sysctl_timer_migration() && idle_cpu(cpu))
cpu = get_nohz_timer_target();
#endif
debug_activate(timer, timer->expires);
internal_add_timer(base, timer);
/*
- * Check whether the other CPU is idle and needs to be
- * triggered to reevaluate the timer wheel when nohz is
- * active. We are protected against the other CPU fiddling
+ * Check whether the other CPU is in dynticks mode and needs
+ * to be triggered to reevaluate the timer wheel.
+ * We are protected against the other CPU fiddling
* with the timer by holding the timer base lock. This also
- * makes sure that a CPU on the way to idle can not evaluate
- * the timer wheel.
+ * makes sure that a CPU on the way to stop its tick can not
+ * evaluate the timer wheel.
*/
- wake_up_idle_cpu(cpu);
+ wake_up_nohz_cpu(cpu);
spin_unlock_irqrestore(&base->lock, flags);
}
EXPORT_SYMBOL_GPL(add_timer_on);
spin_unlock_irq(&base->lock);
}
-#ifdef CONFIG_NO_HZ
+#ifdef CONFIG_NO_HZ_COMMON
/*
* Find out when the next timer event is due to happen. This
* is used on S/390 to stop all activity when a CPU is idle.
#endif
-/**
- * sys_getpid - return the thread group id of the current process
- *
- * Note, despite the name, this returns the tgid not the pid. The tgid and
- * the pid are identical unless CLONE_THREAD was specified on clone() in
- * which case the tgid is the same in all threads of the same group.
- *
- * This is SMP safe as current->tgid does not change.
- */
-SYSCALL_DEFINE0(getpid)
-{
- return task_tgid_vnr(current);
-}
-
-/*
- * Accessing ->real_parent is not SMP-safe, it could
- * change from under us. However, we can use a stale
- * value of ->real_parent under rcu_read_lock(), see
- * release_task()->call_rcu(delayed_put_task_struct).
- */
-SYSCALL_DEFINE0(getppid)
-{
- int pid;
-
- rcu_read_lock();
- pid = task_tgid_vnr(rcu_dereference(current->real_parent));
- rcu_read_unlock();
-
- return pid;
-}
-
-SYSCALL_DEFINE0(getuid)
-{
- /* Only we change this so SMP safe */
- return from_kuid_munged(current_user_ns(), current_uid());
-}
-
-SYSCALL_DEFINE0(geteuid)
-{
- /* Only we change this so SMP safe */
- return from_kuid_munged(current_user_ns(), current_euid());
-}
-
-SYSCALL_DEFINE0(getgid)
-{
- /* Only we change this so SMP safe */
- return from_kgid_munged(current_user_ns(), current_gid());
-}
-
-SYSCALL_DEFINE0(getegid)
-{
- /* Only we change this so SMP safe */
- return from_kgid_munged(current_user_ns(), current_egid());
-}
-
static void process_timeout(unsigned long __data)
{
wake_up_process((struct task_struct *)__data);
}
EXPORT_SYMBOL(schedule_timeout_uninterruptible);
-/* Thread ID - the internal kernel "pid" */
-SYSCALL_DEFINE0(gettid)
-{
- return task_pid_vnr(current);
-}
-
-/**
- * do_sysinfo - fill in sysinfo struct
- * @info: pointer to buffer to fill
- */
-static int do_sysinfo(struct sysinfo *info)
-{
- unsigned long mem_total, sav_total;
- unsigned int mem_unit, bitcount;
- struct timespec tp;
-
- memset(info, 0, sizeof(struct sysinfo));
-
- ktime_get_ts(&tp);
- monotonic_to_bootbased(&tp);
- info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0);
-
- get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT);
-
- info->procs = nr_threads;
-
- si_meminfo(info);
- si_swapinfo(info);
-
- /*
- * If the sum of all the available memory (i.e. ram + swap)
- * is less than can be stored in a 32 bit unsigned long then
- * we can be binary compatible with 2.2.x kernels. If not,
- * well, in that case 2.2.x was broken anyways...
- *
- * -Erik Andersen <andersee@debian.org>
- */
-
- mem_total = info->totalram + info->totalswap;
- if (mem_total < info->totalram || mem_total < info->totalswap)
- goto out;
- bitcount = 0;
- mem_unit = info->mem_unit;
- while (mem_unit > 1) {
- bitcount++;
- mem_unit >>= 1;
- sav_total = mem_total;
- mem_total <<= 1;
- if (mem_total < sav_total)
- goto out;
- }
-
- /*
- * If mem_total did not overflow, multiply all memory values by
- * info->mem_unit and set it to 1. This leaves things compatible
- * with 2.2.x, and also retains compatibility with earlier 2.4.x
- * kernels...
- */
-
- info->mem_unit = 1;
- info->totalram <<= bitcount;
- info->freeram <<= bitcount;
- info->sharedram <<= bitcount;
- info->bufferram <<= bitcount;
- info->totalswap <<= bitcount;
- info->freeswap <<= bitcount;
- info->totalhigh <<= bitcount;
- info->freehigh <<= bitcount;
-
-out:
- return 0;
-}
-
-SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info)
-{
- struct sysinfo val;
-
- do_sysinfo(&val);
-
- if (copy_to_user(info, &val, sizeof(struct sysinfo)))
- return -EFAULT;
-
- return 0;
-}
-
-#ifdef CONFIG_COMPAT
-struct compat_sysinfo {
- s32 uptime;
- u32 loads[3];
- u32 totalram;
- u32 freeram;
- u32 sharedram;
- u32 bufferram;
- u32 totalswap;
- u32 freeswap;
- u16 procs;
- u16 pad;
- u32 totalhigh;
- u32 freehigh;
- u32 mem_unit;
- char _f[20-2*sizeof(u32)-sizeof(int)];
-};
-
-COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
-{
- struct sysinfo s;
-
- do_sysinfo(&s);
-
- /* Check to see if any memory value is too large for 32-bit and scale
- * down if needed
- */
- if ((s.totalram >> 32) || (s.totalswap >> 32)) {
- int bitcount = 0;
-
- while (s.mem_unit < PAGE_SIZE) {
- s.mem_unit <<= 1;
- bitcount++;
- }
-
- s.totalram >>= bitcount;
- s.freeram >>= bitcount;
- s.sharedram >>= bitcount;
- s.bufferram >>= bitcount;
- s.totalswap >>= bitcount;
- s.freeswap >>= bitcount;
- s.totalhigh >>= bitcount;
- s.freehigh >>= bitcount;
- }
-
- if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
- __put_user (s.uptime, &info->uptime) ||
- __put_user (s.loads[0], &info->loads[0]) ||
- __put_user (s.loads[1], &info->loads[1]) ||
- __put_user (s.loads[2], &info->loads[2]) ||
- __put_user (s.totalram, &info->totalram) ||
- __put_user (s.freeram, &info->freeram) ||
- __put_user (s.sharedram, &info->sharedram) ||
- __put_user (s.bufferram, &info->bufferram) ||
- __put_user (s.totalswap, &info->totalswap) ||
- __put_user (s.freeswap, &info->freeswap) ||
- __put_user (s.procs, &info->procs) ||
- __put_user (s.totalhigh, &info->totalhigh) ||
- __put_user (s.freehigh, &info->freehigh) ||
- __put_user (s.mem_unit, &info->mem_unit))
- return -EFAULT;
-
- return 0;
-}
-#endif /* CONFIG_COMPAT */
-
static int __cpuinit init_timers_cpu(int cpu)
{
int j;
Code Review / linux-3.10.git / blobdiff