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-rw-r--r--include/linux/sched.h286
1 files changed, 262 insertions, 24 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 52c4847b05e2..62c68e513e39 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -40,7 +40,6 @@ struct sched_param {
#include <linux/pid.h>
#include <linux/percpu.h>
#include <linux/topology.h>
-#include <linux/proportions.h>
#include <linux/seccomp.h>
#include <linux/rcupdate.h>
#include <linux/rculist.h>
@@ -178,9 +177,11 @@ extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
extern void calc_global_load(unsigned long ticks);
#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
-extern void update_cpu_load_nohz(int active);
+extern void cpu_load_update_nohz_start(void);
+extern void cpu_load_update_nohz_stop(void);
#else
-static inline void update_cpu_load_nohz(int active) { }
+static inline void cpu_load_update_nohz_start(void) { }
+static inline void cpu_load_update_nohz_stop(void) { }
#endif
extern void dump_cpu_task(int cpu);
@@ -218,9 +219,10 @@ extern void proc_sched_set_task(struct task_struct *p);
#define TASK_WAKING 256
#define TASK_PARKED 512
#define TASK_NOLOAD 1024
-#define TASK_STATE_MAX 2048
+#define TASK_NEW 2048
+#define TASK_STATE_MAX 4096
-#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
+#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn"
extern char ___assert_task_state[1 - 2*!!(
sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
@@ -372,6 +374,15 @@ extern void cpu_init (void);
extern void trap_init(void);
extern void update_process_times(int user);
extern void scheduler_tick(void);
+extern int sched_cpu_starting(unsigned int cpu);
+extern int sched_cpu_activate(unsigned int cpu);
+extern int sched_cpu_deactivate(unsigned int cpu);
+
+#ifdef CONFIG_HOTPLUG_CPU
+extern int sched_cpu_dying(unsigned int cpu);
+#else
+# define sched_cpu_dying NULL
+#endif
extern void sched_show_task(struct task_struct *p);
@@ -511,6 +522,8 @@ static inline int get_dumpable(struct mm_struct *mm)
#define MMF_HAS_UPROBES 19 /* has uprobes */
#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */
+#define MMF_OOM_REAPED 21 /* mm has been already reaped */
+#define MMF_OOM_NOT_REAPABLE 22 /* mm couldn't be reaped */
#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
@@ -658,6 +671,7 @@ struct signal_struct {
atomic_t sigcnt;
atomic_t live;
int nr_threads;
+ atomic_t oom_victims; /* # of TIF_MEDIE threads in this thread group */
struct list_head thread_head;
wait_queue_head_t wait_chldexit; /* for wait4() */
@@ -782,7 +796,11 @@ struct signal_struct {
struct tty_audit_buf *tty_audit_buf;
#endif
- oom_flags_t oom_flags;
+ /*
+ * Thread is the potential origin of an oom condition; kill first on
+ * oom
+ */
+ bool oom_flag_origin;
short oom_score_adj; /* OOM kill score adjustment */
short oom_score_adj_min; /* OOM kill score adjustment min value.
* Only settable by CAP_SYS_RESOURCE. */
@@ -935,9 +953,19 @@ enum cpu_idle_type {
};
/*
+ * Integer metrics need fixed point arithmetic, e.g., sched/fair
+ * has a few: load, load_avg, util_avg, freq, and capacity.
+ *
+ * We define a basic fixed point arithmetic range, and then formalize
+ * all these metrics based on that basic range.
+ */
+# define SCHED_FIXEDPOINT_SHIFT 10
+# define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
+
+/*
* Increase resolution of cpu_capacity calculations
*/
-#define SCHED_CAPACITY_SHIFT 10
+#define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
/*
@@ -1199,18 +1227,56 @@ struct load_weight {
};
/*
- * The load_avg/util_avg accumulates an infinite geometric series.
- * 1) load_avg factors frequency scaling into the amount of time that a
- * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
- * aggregated such weights of all runnable and blocked sched_entities.
- * 2) util_avg factors frequency and cpu scaling into the amount of time
- * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
- * For cfs_rq, it is the aggregated such times of all runnable and
+ * The load_avg/util_avg accumulates an infinite geometric series
+ * (see __update_load_avg() in kernel/sched/fair.c).
+ *
+ * [load_avg definition]
+ *
+ * load_avg = runnable% * scale_load_down(load)
+ *
+ * where runnable% is the time ratio that a sched_entity is runnable.
+ * For cfs_rq, it is the aggregated load_avg of all runnable and
* blocked sched_entities.
- * The 64 bit load_sum can:
- * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
- * the highest weight (=88761) always runnable, we should not overflow
- * 2) for entity, support any load.weight always runnable
+ *
+ * load_avg may also take frequency scaling into account:
+ *
+ * load_avg = runnable% * scale_load_down(load) * freq%
+ *
+ * where freq% is the CPU frequency normalized to the highest frequency.
+ *
+ * [util_avg definition]
+ *
+ * util_avg = running% * SCHED_CAPACITY_SCALE
+ *
+ * where running% is the time ratio that a sched_entity is running on
+ * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
+ * and blocked sched_entities.
+ *
+ * util_avg may also factor frequency scaling and CPU capacity scaling:
+ *
+ * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
+ *
+ * where freq% is the same as above, and capacity% is the CPU capacity
+ * normalized to the greatest capacity (due to uarch differences, etc).
+ *
+ * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
+ * themselves are in the range of [0, 1]. To do fixed point arithmetics,
+ * we therefore scale them to as large a range as necessary. This is for
+ * example reflected by util_avg's SCHED_CAPACITY_SCALE.
+ *
+ * [Overflow issue]
+ *
+ * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
+ * with the highest load (=88761), always runnable on a single cfs_rq,
+ * and should not overflow as the number already hits PID_MAX_LIMIT.
+ *
+ * For all other cases (including 32-bit kernels), struct load_weight's
+ * weight will overflow first before we do, because:
+ *
+ * Max(load_avg) <= Max(load.weight)
+ *
+ * Then it is the load_weight's responsibility to consider overflow
+ * issues.
*/
struct sched_avg {
u64 last_update_time, load_sum;
@@ -1475,11 +1541,15 @@ struct task_struct {
unsigned sched_reset_on_fork:1;
unsigned sched_contributes_to_load:1;
unsigned sched_migrated:1;
+ unsigned sched_remote_wakeup:1;
unsigned :0; /* force alignment to the next boundary */
/* unserialized, strictly 'current' */
unsigned in_execve:1; /* bit to tell LSMs we're in execve */
unsigned in_iowait:1;
+#if !defined(TIF_RESTORE_SIGMASK)
+ unsigned restore_sigmask:1;
+#endif
#ifdef CONFIG_MEMCG
unsigned memcg_may_oom:1;
#ifndef CONFIG_SLOB
@@ -1596,6 +1666,7 @@ struct task_struct {
unsigned long sas_ss_sp;
size_t sas_ss_size;
+ unsigned sas_ss_flags;
struct callback_head *task_works;
@@ -1871,12 +1942,43 @@ extern int arch_task_struct_size __read_mostly;
/* Future-safe accessor for struct task_struct's cpus_allowed. */
#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
+static inline int tsk_nr_cpus_allowed(struct task_struct *p)
+{
+ return p->nr_cpus_allowed;
+}
+
#define TNF_MIGRATED 0x01
#define TNF_NO_GROUP 0x02
#define TNF_SHARED 0x04
#define TNF_FAULT_LOCAL 0x08
#define TNF_MIGRATE_FAIL 0x10
+static inline bool in_vfork(struct task_struct *tsk)
+{
+ bool ret;
+
+ /*
+ * need RCU to access ->real_parent if CLONE_VM was used along with
+ * CLONE_PARENT.
+ *
+ * We check real_parent->mm == tsk->mm because CLONE_VFORK does not
+ * imply CLONE_VM
+ *
+ * CLONE_VFORK can be used with CLONE_PARENT/CLONE_THREAD and thus
+ * ->real_parent is not necessarily the task doing vfork(), so in
+ * theory we can't rely on task_lock() if we want to dereference it.
+ *
+ * And in this case we can't trust the real_parent->mm == tsk->mm
+ * check, it can be false negative. But we do not care, if init or
+ * another oom-unkillable task does this it should blame itself.
+ */
+ rcu_read_lock();
+ ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm;
+ rcu_read_unlock();
+
+ return ret;
+}
+
#ifdef CONFIG_NUMA_BALANCING
extern void task_numa_fault(int last_node, int node, int pages, int flags);
extern pid_t task_numa_group_id(struct task_struct *p);
@@ -2068,6 +2170,9 @@ static inline void put_task_struct(struct task_struct *t)
__put_task_struct(t);
}
+struct task_struct *task_rcu_dereference(struct task_struct **ptask);
+struct task_struct *try_get_task_struct(struct task_struct **ptask);
+
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
extern void task_cputime(struct task_struct *t,
cputime_t *utime, cputime_t *stime);
@@ -2184,6 +2289,7 @@ static inline void memalloc_noio_restore(unsigned int flags)
#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
+#define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */
#define TASK_PFA_TEST(name, func) \
@@ -2207,6 +2313,9 @@ TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
TASK_PFA_SET(SPREAD_SLAB, spread_slab)
TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
+TASK_PFA_TEST(LMK_WAITING, lmk_waiting)
+TASK_PFA_SET(LMK_WAITING, lmk_waiting)
+
/*
* task->jobctl flags
*/
@@ -2303,8 +2412,6 @@ extern unsigned long long notrace sched_clock(void);
/*
* See the comment in kernel/sched/clock.c
*/
-extern u64 cpu_clock(int cpu);
-extern u64 local_clock(void);
extern u64 running_clock(void);
extern u64 sched_clock_cpu(int cpu);
@@ -2323,6 +2430,16 @@ static inline void sched_clock_idle_sleep_event(void)
static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
{
}
+
+static inline u64 cpu_clock(int cpu)
+{
+ return sched_clock();
+}
+
+static inline u64 local_clock(void)
+{
+ return sched_clock();
+}
#else
/*
* Architectures can set this to 1 if they have specified
@@ -2337,6 +2454,26 @@ extern void clear_sched_clock_stable(void);
extern void sched_clock_tick(void);
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
+
+/*
+ * As outlined in clock.c, provides a fast, high resolution, nanosecond
+ * time source that is monotonic per cpu argument and has bounded drift
+ * between cpus.
+ *
+ * ######################### BIG FAT WARNING ##########################
+ * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can #
+ * # go backwards !! #
+ * ####################################################################
+ */
+static inline u64 cpu_clock(int cpu)
+{
+ return sched_clock_cpu(cpu);
+}
+
+static inline u64 local_clock(void)
+{
+ return sched_clock_cpu(raw_smp_processor_id());
+}
#endif
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
@@ -2546,6 +2683,66 @@ extern void sigqueue_free(struct sigqueue *);
extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
+#ifdef TIF_RESTORE_SIGMASK
+/*
+ * Legacy restore_sigmask accessors. These are inefficient on
+ * SMP architectures because they require atomic operations.
+ */
+
+/**
+ * set_restore_sigmask() - make sure saved_sigmask processing gets done
+ *
+ * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
+ * will run before returning to user mode, to process the flag. For
+ * all callers, TIF_SIGPENDING is already set or it's no harm to set
+ * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the
+ * arch code will notice on return to user mode, in case those bits
+ * are scarce. We set TIF_SIGPENDING here to ensure that the arch
+ * signal code always gets run when TIF_RESTORE_SIGMASK is set.
+ */
+static inline void set_restore_sigmask(void)
+{
+ set_thread_flag(TIF_RESTORE_SIGMASK);
+ WARN_ON(!test_thread_flag(TIF_SIGPENDING));
+}
+static inline void clear_restore_sigmask(void)
+{
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+}
+static inline bool test_restore_sigmask(void)
+{
+ return test_thread_flag(TIF_RESTORE_SIGMASK);
+}
+static inline bool test_and_clear_restore_sigmask(void)
+{
+ return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
+}
+
+#else /* TIF_RESTORE_SIGMASK */
+
+/* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */
+static inline void set_restore_sigmask(void)
+{
+ current->restore_sigmask = true;
+ WARN_ON(!test_thread_flag(TIF_SIGPENDING));
+}
+static inline void clear_restore_sigmask(void)
+{
+ current->restore_sigmask = false;
+}
+static inline bool test_restore_sigmask(void)
+{
+ return current->restore_sigmask;
+}
+static inline bool test_and_clear_restore_sigmask(void)
+{
+ if (!current->restore_sigmask)
+ return false;
+ current->restore_sigmask = false;
+ return true;
+}
+#endif
+
static inline void restore_saved_sigmask(void)
{
if (test_and_clear_restore_sigmask())
@@ -2575,6 +2772,18 @@ static inline int kill_cad_pid(int sig, int priv)
*/
static inline int on_sig_stack(unsigned long sp)
{
+ /*
+ * If the signal stack is SS_AUTODISARM then, by construction, we
+ * can't be on the signal stack unless user code deliberately set
+ * SS_AUTODISARM when we were already on it.
+ *
+ * This improves reliability: if user state gets corrupted such that
+ * the stack pointer points very close to the end of the signal stack,
+ * then this check will enable the signal to be handled anyway.
+ */
+ if (current->sas_ss_flags & SS_AUTODISARM)
+ return 0;
+
#ifdef CONFIG_STACK_GROWSUP
return sp >= current->sas_ss_sp &&
sp - current->sas_ss_sp < current->sas_ss_size;
@@ -2592,6 +2801,13 @@ static inline int sas_ss_flags(unsigned long sp)
return on_sig_stack(sp) ? SS_ONSTACK : 0;
}
+static inline void sas_ss_reset(struct task_struct *p)
+{
+ p->sas_ss_sp = 0;
+ p->sas_ss_size = 0;
+ p->sas_ss_flags = SS_DISABLE;
+}
+
static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
{
if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
@@ -2610,14 +2826,26 @@ extern struct mm_struct * mm_alloc(void);
/* mmdrop drops the mm and the page tables */
extern void __mmdrop(struct mm_struct *);
-static inline void mmdrop(struct mm_struct * mm)
+static inline void mmdrop(struct mm_struct *mm)
{
if (unlikely(atomic_dec_and_test(&mm->mm_count)))
__mmdrop(mm);
}
+static inline bool mmget_not_zero(struct mm_struct *mm)
+{
+ return atomic_inc_not_zero(&mm->mm_users);
+}
+
/* mmput gets rid of the mappings and all user-space */
extern void mmput(struct mm_struct *);
+#ifdef CONFIG_MMU
+/* same as above but performs the slow path from the async context. Can
+ * be called from the atomic context as well
+ */
+extern void mmput_async(struct mm_struct *);
+#endif
+
/* Grab a reference to a task's mm, if it is not already going away */
extern struct mm_struct *get_task_mm(struct task_struct *task);
/*
@@ -2646,7 +2874,14 @@ static inline int copy_thread_tls(
}
#endif
extern void flush_thread(void);
-extern void exit_thread(void);
+
+#ifdef CONFIG_HAVE_EXIT_THREAD
+extern void exit_thread(struct task_struct *tsk);
+#else
+static inline void exit_thread(struct task_struct *tsk)
+{
+}
+#endif
extern void exit_files(struct task_struct *);
extern void __cleanup_sighand(struct sighand_struct *);
@@ -2866,7 +3101,7 @@ static inline int object_is_on_stack(void *obj)
return (obj >= stack) && (obj < (stack + THREAD_SIZE));
}
-extern void thread_info_cache_init(void);
+extern void thread_stack_cache_init(void);
#ifdef CONFIG_DEBUG_STACK_USAGE
static inline unsigned long stack_not_used(struct task_struct *p)
@@ -3240,7 +3475,10 @@ struct update_util_data {
u64 time, unsigned long util, unsigned long max);
};
-void cpufreq_set_update_util_data(int cpu, struct update_util_data *data);
+void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
+ void (*func)(struct update_util_data *data, u64 time,
+ unsigned long util, unsigned long max));
+void cpufreq_remove_update_util_hook(int cpu);
#endif /* CONFIG_CPU_FREQ */
#endif