1 files changed, 170 insertions, 16 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 53f97eb8dbc7..a781dec1cd0b 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -16,6 +16,7 @@ struct sched_param {
 #include <linux/types.h>
 #include <linux/timex.h>
 #include <linux/jiffies.h>
+#include <linux/plist.h>
 #include <linux/rbtree.h>
 #include <linux/thread_info.h>
 #include <linux/cpumask.h>
@@ -56,6 +57,70 @@ struct sched_param {
 
 #include <asm/processor.h>
 
+#define SCHED_ATTR_SIZE_VER0    48      /* sizeof first published struct */
+
+/*
+ * Extended scheduling parameters data structure.
+ *
+ * This is needed because the original struct sched_param can not be
+ * altered without introducing ABI issues with legacy applications
+ * (e.g., in sched_getparam()).
+ *
+ * However, the possibility of specifying more than just a priority for
+ * the tasks may be useful for a wide variety of application fields, e.g.,
+ * multimedia, streaming, automation and control, and many others.
+ *
+ * This variant (sched_attr) is meant at describing a so-called
+ * sporadic time-constrained task. In such model a task is specified by:
+ *  - the activation period or minimum instance inter-arrival time;
+ *  - the maximum (or average, depending on the actual scheduling
+ *    discipline) computation time of all instances, a.k.a. runtime;
+ *  - the deadline (relative to the actual activation time) of each
+ *    instance.
+ * Very briefly, a periodic (sporadic) task asks for the execution of
+ * some specific computation --which is typically called an instance--
+ * (at most) every period. Moreover, each instance typically lasts no more
+ * than the runtime and must be completed by time instant t equal to
+ * the instance activation time + the deadline.
+ *
+ * This is reflected by the actual fields of the sched_attr structure:
+ *
+ *  @size               size of the structure, for fwd/bwd compat.
+ *
+ *  @sched_policy       task's scheduling policy
+ *  @sched_flags        for customizing the scheduler behaviour
+ *  @sched_nice         task's nice value      (SCHED_NORMAL/BATCH)
+ *  @sched_priority     task's static priority (SCHED_FIFO/RR)
+ *  @sched_deadline     representative of the task's deadline
+ *  @sched_runtime      representative of the task's runtime
+ *  @sched_period       representative of the task's period
+ *
+ * Given this task model, there are a multiplicity of scheduling algorithms
+ * and policies, that can be used to ensure all the tasks will make their
+ * timing constraints.
+ *
+ * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
+ * only user of this new interface. More information about the algorithm
+ * available in the scheduling class file or in Documentation/.
+ */
+struct sched_attr {
+        u32 size;
+
+        u32 sched_policy;
+        u64 sched_flags;
+
+        /* SCHED_NORMAL, SCHED_BATCH */
+        s32 sched_nice;
+
+        /* SCHED_FIFO, SCHED_RR */
+        u32 sched_priority;
+
+        /* SCHED_DEADLINE */
+        u64 sched_runtime;
+        u64 sched_deadline;
+        u64 sched_period;
+};
+
 struct exec_domain;
 struct futex_pi_state;
 struct robust_list_head;
@@ -63,6 +128,7 @@ struct bio_list;
 struct fs_struct;
 struct perf_event_context;
 struct blk_plug;
+struct filename;
 
 /*
  * List of flags we want to share for kernel threads,
@@ -164,11 +230,10 @@ extern char ___assert_task_state[1 - 2*!!(
 /* get_task_state() */
 #define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
                                  TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
-                                 __TASK_TRACED)
+                                 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
 
 #define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
 #define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
-#define task_is_dead(task)      ((task)->exit_state != 0)
 #define task_is_stopped_or_traced(task) \
                         ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
 #define task_contributes_to_load(task)  \
@@ -327,22 +392,33 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
 #endif
 
-
-extern void set_dumpable(struct mm_struct *mm, int value);
-extern int get_dumpable(struct mm_struct *mm);
-
 #define SUID_DUMP_DISABLE       0       /* No setuid dumping */
 #define SUID_DUMP_USER          1       /* Dump as user of process */
 #define SUID_DUMP_ROOT          2       /* Dump as root */
 
 /* mm flags */
-/* dumpable bits */
-#define MMF_DUMPABLE      0  /* core dump is permitted */
-#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
 
+/* for SUID_DUMP_* above */
 #define MMF_DUMPABLE_BITS 2
 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
 
+extern void set_dumpable(struct mm_struct *mm, int value);
+/*
+ * This returns the actual value of the suid_dumpable flag. For things
+ * that are using this for checking for privilege transitions, it must
+ * test against SUID_DUMP_USER rather than treating it as a boolean
+ * value.
+ */
+static inline int __get_dumpable(unsigned long mm_flags)
+{
+        return mm_flags & MMF_DUMPABLE_MASK;
+}
+
+static inline int get_dumpable(struct mm_struct *mm)
+{
+        return __get_dumpable(mm->flags);
+}
+
 /* coredump filter bits */
 #define MMF_DUMP_ANON_PRIVATE   2
 #define MMF_DUMP_ANON_SHARED    3
@@ -485,6 +561,7 @@ struct signal_struct {
         atomic_t                sigcnt;
         atomic_t                live;
         int                     nr_threads;
+        struct list_head        thread_head;
 
         wait_queue_head_t       wait_chldexit;  /* for wait4() */
 
@@ -1029,6 +1106,51 @@ struct sched_rt_entity {
 #endif
 };
 
+struct sched_dl_entity {
+        struct rb_node  rb_node;
+
+        /*
+         * Original scheduling parameters. Copied here from sched_attr
+         * during sched_setscheduler2(), they will remain the same until
+         * the next sched_setscheduler2().
+         */
+        u64 dl_runtime;         /* maximum runtime for each instance    */
+        u64 dl_deadline;        /* relative deadline of each instance   */
+        u64 dl_period;          /* separation of two instances (period) */
+        u64 dl_bw;              /* dl_runtime / dl_deadline             */
+
+        /*
+         * Actual scheduling parameters. Initialized with the values above,
+         * they are continously updated during task execution. Note that
+         * the remaining runtime could be < 0 in case we are in overrun.
+         */
+        s64 runtime;            /* remaining runtime for this instance  */
+        u64 deadline;           /* absolute deadline for this instance  */
+        unsigned int flags;     /* specifying the scheduler behaviour   */
+
+        /*
+         * Some bool flags:
+         *
+         * @dl_throttled tells if we exhausted the runtime. If so, the
+         * task has to wait for a replenishment to be performed at the
+         * next firing of dl_timer.
+         *
+         * @dl_new tells if a new instance arrived. If so we must
+         * start executing it with full runtime and reset its absolute
+         * deadline;
+         *
+         * @dl_boosted tells if we are boosted due to DI. If so we are
+         * outside bandwidth enforcement mechanism (but only until we
+         * exit the critical section).
+         */
+        int dl_throttled, dl_new, dl_boosted;
+
+        /*
+         * Bandwidth enforcement timer. Each -deadline task has its
+         * own bandwidth to be enforced, thus we need one timer per task.
+         */
+        struct hrtimer dl_timer;
+};
 
 struct rcu_node;
 
@@ -1065,6 +1187,7 @@ struct task_struct {
 #ifdef CONFIG_CGROUP_SCHED
         struct task_group *sched_task_group;
 #endif
+        struct sched_dl_entity dl;
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS
         /* list of struct preempt_notifier: */
@@ -1098,6 +1221,7 @@ struct task_struct {
         struct list_head tasks;
 #ifdef CONFIG_SMP
         struct plist_node pushable_tasks;
+        struct rb_node pushable_dl_tasks;
 #endif
 
         struct mm_struct *mm, *active_mm;
@@ -1116,7 +1240,6 @@ struct task_struct {
         /* Used for emulating ABI behavior of previous Linux versions */
         unsigned int personality;
 
-        unsigned did_exec:1;
         unsigned in_execve:1;   /* Tell the LSMs that the process is doing an
                                  * execve */
         unsigned in_iowait:1;
@@ -1160,6 +1283,7 @@ struct task_struct {
         /* PID/PID hash table linkage. */
         struct pid_link pids[PIDTYPE_MAX];
         struct list_head thread_group;
+        struct list_head thread_node;
 
         struct completion *vfork_done;          /* for vfork() */
         int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
@@ -1249,9 +1373,12 @@ struct task_struct {
 
 #ifdef CONFIG_RT_MUTEXES
         /* PI waiters blocked on a rt_mutex held by this task */
-        struct plist_head pi_waiters;
+        struct rb_root pi_waiters;
+        struct rb_node *pi_waiters_leftmost;
         /* Deadlock detection and priority inheritance handling */
         struct rt_mutex_waiter *pi_blocked_on;
+        /* Top pi_waiters task */
+        struct task_struct *pi_top_task;
 #endif
 
 #ifdef CONFIG_DEBUG_MUTEXES
@@ -1880,7 +2007,9 @@ static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
  * but then during bootup it turns out that sched_clock()
  * is reliable after all:
  */
-extern int sched_clock_stable;
+extern int sched_clock_stable(void);
+extern void set_sched_clock_stable(void);
+extern void clear_sched_clock_stable(void);
 
 extern void sched_clock_tick(void);
 extern void sched_clock_idle_sleep_event(void);
@@ -1959,6 +2088,8 @@ extern int sched_setscheduler(struct task_struct *, int,
                               const struct sched_param *);
 extern int sched_setscheduler_nocheck(struct task_struct *, int,
                                       const struct sched_param *);
+extern int sched_setattr(struct task_struct *,
+                         const struct sched_attr *);
 extern struct task_struct *idle_task(int cpu);
 /**
  * is_idle_task - is the specified task an idle task?
@@ -2038,7 +2169,7 @@ extern void wake_up_new_task(struct task_struct *tsk);
 #else
  static inline void kick_process(struct task_struct *tsk) { }
 #endif
-extern void sched_fork(unsigned long clone_flags, struct task_struct *p);
+extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
 extern void sched_dead(struct task_struct *p);
 
 extern void proc_caches_init(void);
@@ -2164,8 +2295,6 @@ extern struct mm_struct *get_task_mm(struct task_struct *task);
 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
 /* Remove the current tasks stale references to the old mm_struct */
 extern void mm_release(struct task_struct *, struct mm_struct *);
-/* Allocate a new mm structure and copy contents from tsk->mm */
-extern struct mm_struct *dup_mm(struct task_struct *tsk);
 
 extern int copy_thread(unsigned long, unsigned long, unsigned long,
                         struct task_struct *);
@@ -2183,7 +2312,7 @@ extern void do_group_exit(int);
 extern int allow_signal(int);
 extern int disallow_signal(int);
 
-extern int do_execve(const char *,
+extern int do_execve(struct filename *,
                      const char __user * const __user *,
                      const char __user * const __user *);
 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
@@ -2223,6 +2352,16 @@ extern bool current_is_single_threaded(void);
 #define while_each_thread(g, t) \
         while ((t = next_thread(t)) != g)
 
+#define __for_each_thread(signal, t)    \
+        list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
+
+#define for_each_thread(p, t)           \
+        __for_each_thread((p)->signal, t)
+
+/* Careful: this is a double loop, 'break' won't work as expected. */
+#define for_each_process_thread(p, t)   \
+        for_each_process(p) for_each_thread(p, t)
+
 static inline int get_nr_threads(struct task_struct *tsk)
 {
         return tsk->signal->nr_threads;
@@ -2627,6 +2766,21 @@ static inline bool __must_check current_clr_polling_and_test(void)
 }
 #endif
 
+static inline void current_clr_polling(void)
+{
+        __current_clr_polling();
+
+        /*
+         * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
+         * Once the bit is cleared, we'll get IPIs with every new
+         * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
+         * fold.
+         */
+        smp_mb(); /* paired with resched_task() */
+
+        preempt_fold_need_resched();
+}
+
 static __always_inline bool need_resched(void)
 {
         return unlikely(tif_need_resched());