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-rw-r--r--include/asm-generic/resource.h5
-rw-r--r--include/linux/sched.h1
-rw-r--r--kernel/posix-cpu-timers.c29
-rw-r--r--kernel/sched_rt.c30
4 files changed, 63 insertions, 2 deletions
diff --git a/include/asm-generic/resource.h b/include/asm-generic/resource.h
index a4a22cc3589..587566f95f6 100644
--- a/include/asm-generic/resource.h
+++ b/include/asm-generic/resource.h
@@ -44,8 +44,8 @@
#define RLIMIT_NICE 13 /* max nice prio allowed to raise to
0-39 for nice level 19 .. -20 */
#define RLIMIT_RTPRIO 14 /* maximum realtime priority */
-
-#define RLIM_NLIMITS 15
+#define RLIMIT_RTTIME 15 /* timeout for RT tasks in us */
+#define RLIM_NLIMITS 16
/*
* SuS says limits have to be unsigned.
@@ -86,6 +86,7 @@
[RLIMIT_MSGQUEUE] = { MQ_BYTES_MAX, MQ_BYTES_MAX }, \
[RLIMIT_NICE] = { 0, 0 }, \
[RLIMIT_RTPRIO] = { 0, 0 }, \
+ [RLIMIT_RTTIME] = { RLIM_INFINITY, RLIM_INFINITY }, \
}
#endif /* __KERNEL__ */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a06d09ebd5c..fe3f8fbc614 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -932,6 +932,7 @@ struct sched_entity {
struct sched_rt_entity {
struct list_head run_list;
unsigned int time_slice;
+ unsigned long timeout;
};
struct task_struct {
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index 68c96376e84..2c076b36c4f 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -967,6 +967,7 @@ static void check_thread_timers(struct task_struct *tsk,
{
int maxfire;
struct list_head *timers = tsk->cpu_timers;
+ struct signal_struct *const sig = tsk->signal;
maxfire = 20;
tsk->it_prof_expires = cputime_zero;
@@ -1011,6 +1012,34 @@ static void check_thread_timers(struct task_struct *tsk,
t->firing = 1;
list_move_tail(&t->entry, firing);
}
+
+ /*
+ * Check for the special case thread timers.
+ */
+ if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) {
+ unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
+ unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur;
+
+ if (tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
+ /*
+ * At the hard limit, we just die.
+ * No need to calculate anything else now.
+ */
+ __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
+ return;
+ }
+ if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) {
+ /*
+ * At the soft limit, send a SIGXCPU every second.
+ */
+ if (sig->rlim[RLIMIT_RTTIME].rlim_cur
+ < sig->rlim[RLIMIT_RTTIME].rlim_max) {
+ sig->rlim[RLIMIT_RTTIME].rlim_cur +=
+ USEC_PER_SEC;
+ }
+ __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
+ }
+ }
}
/*
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 29963af782a..f350f7b1515 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -116,6 +116,9 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
inc_cpu_load(rq, p->se.load.weight);
inc_rt_tasks(p, rq);
+
+ if (wakeup)
+ p->rt.timeout = 0;
}
/*
@@ -834,11 +837,38 @@ static void prio_changed_rt(struct rq *rq, struct task_struct *p,
}
}
+static void watchdog(struct rq *rq, struct task_struct *p)
+{
+ unsigned long soft, hard;
+
+ if (!p->signal)
+ return;
+
+ soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur;
+ hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max;
+
+ if (soft != RLIM_INFINITY) {
+ unsigned long next;
+
+ p->rt.timeout++;
+ next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
+ if (next > p->rt.timeout) {
+ u64 next_time = p->se.sum_exec_runtime;
+
+ next_time += next * (NSEC_PER_SEC/HZ);
+ if (p->it_sched_expires > next_time)
+ p->it_sched_expires = next_time;
+ } else
+ p->it_sched_expires = p->se.sum_exec_runtime;
+ }
+}
static void task_tick_rt(struct rq *rq, struct task_struct *p)
{
update_curr_rt(rq);
+ watchdog(rq, p);
+
/*
* RR tasks need a special form of timeslice management.
* FIFO tasks have no timeslices.