--- /dev/null
+diff -uprN linux-2.6.28/arch/arm/include/asm/unistd.h linux-2.6.28.new/arch/arm/include/asm/unistd.h
+--- linux-2.6.28/arch/arm/include/asm/unistd.h 2011-05-28 17:55:10.888715216 +0200
++++ linux-2.6.28.new/arch/arm/include/asm/unistd.h 2011-05-28 19:23:05.739661865 +0200
+@@ -387,6 +387,9 @@
+ #define __NR_dup3 (__NR_SYSCALL_BASE+358)
+ #define __NR_pipe2 (__NR_SYSCALL_BASE+359)
+ #define __NR_inotify_init1 (__NR_SYSCALL_BASE+360)
++#define __NR_latnice (__NR_SYSCALL_BASE+361)
++#define __NR_setlatnice (__NR_SYSCALL_BASE+362)
++#define __NR_getlatnice (__NR_SYSCALL_BASE+363)
+
+ /*
+ * The following SWIs are ARM private.
+diff -uprN linux-2.6.28/arch/arm/kernel/calls.S linux-2.6.28.new/arch/arm/kernel/calls.S
+--- linux-2.6.28/arch/arm/kernel/calls.S 2011-05-28 17:54:42.354377786 +0200
++++ linux-2.6.28.new/arch/arm/kernel/calls.S 2011-05-28 18:00:41.705628818 +0200
+@@ -370,6 +370,9 @@
+ CALL(sys_dup3)
+ CALL(sys_pipe2)
+ /* 360 */ CALL(sys_inotify_init1)
++ CALL(sys_latnice)
++ CALL(sys_setlatnice)
++ CALL(sys_getlatnice)
+ #ifndef syscalls_counted
+ .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls
+ #define syscalls_counted
+diff -uprN linux-2.6.28/include/linux/init_task.h linux-2.6.28.new/include/linux/init_task.h
+--- linux-2.6.28/include/linux/init_task.h 2011-05-28 18:08:36.442148441 +0200
++++ linux-2.6.28.new/include/linux/init_task.h 2011-05-28 18:07:40.471745225 +0200
+@@ -133,6 +133,7 @@ extern struct group_info init_groups;
+ .prio = NORMAL_PRIO, \
+ .static_prio = MAX_PRIO-20, \
+ .normal_prio = NORMAL_PRIO, \
++ .latnice = 1, \
+ .deadline = 0, \
+ .policy = SCHED_NORMAL, \
+ .cpus_allowed = CPU_MASK_ALL, \
+diff -uprN linux-2.6.28/include/linux/sched.h linux-2.6.28.new/include/linux/sched.h
+--- linux-2.6.28/include/linux/sched.h 2011-05-28 18:09:18.241185206 +0200
++++ linux-2.6.28.new/include/linux/sched.h 2011-05-28 19:16:33.081566466 +0200
+@@ -1118,7 +1118,7 @@ struct task_struct {
+ int oncpu;
+ #endif
+
+- int prio, static_prio, normal_prio;
++ int prio, static_prio, normal_prio, latnice;
+ unsigned int rt_priority;
+ #ifdef CONFIG_SCHED_BFS
+ int time_slice;
+diff -uprN linux-2.6.28/include/linux/syscalls.h linux-2.6.28.new/include/linux/syscalls.h
+--- linux-2.6.28/include/linux/syscalls.h 2011-05-28 18:08:46.013191142 +0200
++++ linux-2.6.28.new/include/linux/syscalls.h 2011-05-28 19:16:05.936280778 +0200
+@@ -207,6 +207,9 @@ asmlinkage long sys_clock_nanosleep(cloc
+ struct timespec __user *rmtp);
+
+ asmlinkage long sys_nice(int increment);
++asmlinkage long sys_latnice(int latnice);
++asmlinkage long sys_setlatnice(pid_t pid, int latnice);
++asmlinkage long sys_getlatnice(pid_t pid);
+ asmlinkage long sys_sched_setscheduler(pid_t pid, int policy,
+ struct sched_param __user *param);
+ asmlinkage long sys_sched_setparam(pid_t pid,
+diff -uprN linux-2.6.28/kernel/sched_bfs.c linux-2.6.28.new/kernel/sched_bfs.c
+--- linux-2.6.28/kernel/sched_bfs.c 2011-05-28 18:10:39.803808798 +0200
++++ linux-2.6.28.new/kernel/sched_bfs.c 2011-05-28 20:33:37.485040832 +0200
+@@ -153,6 +153,8 @@ int rr_interval __read_mostly = 6;
+ */
+ int sched_iso_cpu __read_mostly = 70;
+
++int sched_interactive __read_mostly = 2;
++
+ /*
+ * group_thread_accounting - sysctl to decide whether to treat whole thread
+ * groups as a single entity for the purposes of CPU distribution.
+@@ -2669,14 +2671,22 @@ EXPORT_SYMBOL(sub_preempt_count);
+ * proportion works out to the square of the virtual deadline difference, so
+ * this equation will give nice 19 3% CPU compared to nice 0.
+ */
+-static inline u64 prio_deadline_diff(int user_prio)
++static inline u64 prio_deadline_diff(int user_prio, int latnice)
+ {
+- return (prio_ratios[user_prio] * rr_interval * (MS_TO_NS(1) / 128));
++ u64 pdd = prio_ratios[user_prio] * rr_interval;
++
++ pdd *= MS_TO_NS(1) / 128;
++ if (!latnice)
++ pdd <<= 1;
++ else if (latnice > 1)
++ pdd >>= latnice - 1;
++
++ return pdd;
+ }
+
+ static inline u64 __task_deadline_diff(struct task_struct *p)
+ {
+- return prio_deadline_diff(TASK_USER_PRIO(p));
++ return prio_deadline_diff(TASK_USER_PRIO(p), p->latnice);
+ }
+
+ static inline u64 task_deadline_diff(struct task_struct *p)
+@@ -2690,12 +2700,12 @@ static inline u64 task_deadline_diff(str
+
+ static inline u64 static_deadline_diff(int static_prio)
+ {
+- return prio_deadline_diff(USER_PRIO(static_prio));
++ return prio_deadline_diff(USER_PRIO(static_prio), 1);
+ }
+
+ static inline int longest_deadline_diff(void)
+ {
+- return prio_deadline_diff(39);
++ return prio_deadline_diff(39, 0);
+ }
+
+ static inline int ms_longest_deadline_diff(void)
+@@ -2710,6 +2720,8 @@ static inline int ms_longest_deadline_di
+ static void time_slice_expired(struct task_struct *p)
+ {
+ u64 tdd = task_deadline_diff(p);
++ unsigned long ts = timeslice();
++ int latnice = p->latnice;
+
+ /*
+ * We proportionately increase the deadline according to how many
+@@ -2724,7 +2736,24 @@ static void time_slice_expired(struct ta
+ if (*threads_running > 1)
+ tdd += *threads_running * __task_deadline_diff(p);
+ }
+- p->time_slice = timeslice();
++
++ switch (sched_interactive) {
++ case 0:
++ if (!latnice)
++ ts <<= 1;
++ else if (latnice > 1)
++ ts >>= latnice - 1;
++ break;
++ case 1:
++ break;
++ case 2:
++ if (!latnice)
++ ts >>= 1;
++ else if (latnice > 1)
++ ts <<= latnice - 1;
++ break;
++ }
++ p->time_slice = ts;
+ p->deadline_niffy = grq.niffies;
+ p->deadline = grq.niffies + tdd;
+ }
+@@ -3524,6 +3553,104 @@ asmlinkage long sys_nice(int increment)
+
+ #endif
+
++static bool __check_same_owner(struct task_struct *p)
++{
++ uid_t euid = current_euid();
++ bool match;
++
++ rcu_read_lock();
++ match = (euid == task_euid(p) ||
++ euid == task_uid(p));
++ return match;
++}
++
++static bool check_same_owner(struct task_struct *p)
++{
++ bool match;
++
++ rcu_read_lock();
++ match = __check_same_owner(p);
++ rcu_read_unlock();
++ return match;
++}
++
++SYSCALL_DEFINE1(latnice, int, latnice)
++{
++ struct task_struct *p = current;
++ unsigned long flags;
++ struct rq *rq;
++
++ if (latnice < 0)
++ latnice = 0;
++ if (latnice > 3)
++ latnice = 3;
++
++ if (!check_same_owner(p))
++ return -EPERM;
++
++ rq = time_task_grq_lock(p, &flags);
++ p->latnice = latnice;
++ task_grq_unlock(&flags);
++
++ return 0;
++}
++
++static inline struct task_struct *find_process_by_pid(pid_t pid);
++
++SYSCALL_DEFINE2(setlatnice, pid_t, pid, int, latnice)
++{
++ struct task_struct *p;
++ int retval = -EINVAL;
++ unsigned long flags;
++ struct rq *rq;
++
++ if (pid < 0)
++ goto out_nounlock;
++
++ retval = -ESRCH;
++ rcu_read_lock();
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++ if (!__check_same_owner(p)) {
++ retval = -EPERM;
++ goto out_unlock;
++ }
++
++ rq = time_task_grq_lock(p, &flags);
++ p->latnice = latnice;
++ task_grq_unlock(&flags);
++ retval = 0;
++
++out_unlock:
++ rcu_read_unlock();
++out_nounlock:
++ return retval;
++
++}
++
++SYSCALL_DEFINE1(getlatnice, pid_t, pid)
++{
++ struct task_struct *p;
++ int retval = -EINVAL;
++
++ if (pid < 0)
++ goto out_nounlock;
++
++ retval = -ESRCH;
++ rcu_read_lock();
++ p = find_process_by_pid(pid);
++ if (!p)
++ goto out_unlock;
++ retval = p->latnice;
++
++out_unlock:
++ rcu_read_unlock();
++out_nounlock:
++ return retval;
++
++}
++
+ /**
+ * task_prio - return the priority value of a given task.
+ * @p: the task in question.
+diff -uprN linux-2.6.28/kernel/sysctl.c linux-2.6.28.new/kernel/sysctl.c
+--- linux-2.6.28/kernel/sysctl.c 2011-05-28 18:10:57.710020361 +0200
++++ linux-2.6.28.new/kernel/sysctl.c 2011-05-28 19:15:03.708077897 +0200
+@@ -102,6 +102,7 @@ static int __read_mostly one_hundred = 1
+ #ifdef CONFIG_SCHED_BFS
+ extern int rr_interval;
+ extern int sched_iso_cpu;
++extern int sched_interactive;
+ extern int group_thread_accounting;
+ extern int fork_depth_penalty;
+ static int __read_mostly one_thousand = 1000;
+@@ -748,6 +749,15 @@ static struct ctl_table kern_table[] = {
+ .extra2 = &one_hundred,
+ },
+ {
++ .procname = "interactive",
++ .data = &sched_interactive,
++ .maxlen = sizeof(int),
++ .mode = 0644,
++ .proc_handler = &proc_dointvec_minmax,
++ .extra1 = &zero,
++ .extra2 = &two,
++ },
++ {
+ .procname = "group_thread_accounting",
+ .data = &group_thread_accounting,
+ .maxlen = sizeof (int),
projects / kernel-bfs / commitdiff