diff options
| -rw-r--r-- | include/uapi/linux/prctl.h | 6 | ||||
| -rw-r--r-- | kernel/sys.c | 19 |
2 files changed, 25 insertions, 0 deletions
diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 253856a2a8ad..28bb0b3a08bf 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -149,6 +149,12 @@ #define PR_GET_TID_ADDRESS 40 +/* Sets the timerslack for arbitrary threads + * arg2 slack value, 0 means "use default" + * arg3 pid of the thread whose timer slack needs to be set + */ +#define PR_SET_TIMERSLACK_PID 41 + #define PR_SET_VMA 0x53564d41 # define PR_SET_VMA_ANON_NAME 0 diff --git a/kernel/sys.c b/kernel/sys.c index 126b7c939d1f..875529e936ab 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -44,6 +44,7 @@ #include <linux/ctype.h> #include <linux/mm.h> #include <linux/mempolicy.h> +#include <linux/sched.h> #include <linux/compat.h> #include <linux/syscalls.h> @@ -2252,6 +2253,7 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, unsigned long, arg4, unsigned long, arg5) { struct task_struct *me = current; + struct task_struct *tsk; unsigned char comm[sizeof(me->comm)]; long error; @@ -2375,6 +2377,23 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, else return -EINVAL; break; + case PR_SET_TIMERSLACK_PID: + rcu_read_lock(); + tsk = find_task_by_pid_ns((pid_t)arg3, &init_pid_ns); + if (tsk == NULL) { + rcu_read_unlock(); + return -EINVAL; + } + get_task_struct(tsk); + rcu_read_unlock(); + if (arg2 <= 0) + tsk->timer_slack_ns = + tsk->default_timer_slack_ns; + else + tsk->timer_slack_ns = arg2; + put_task_struct(tsk); + error = 0; + break; default: return -EINVAL; } |