diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpu.c | 8 | ||||
| -rw-r--r-- | kernel/futex.c | 41 | ||||
| -rw-r--r-- | kernel/power/qos.c | 63 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 4 |
4 files changed, 94 insertions, 22 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 42bd331ee0ab..f45657f1eb8e 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -348,11 +348,13 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; struct task_struct *idle; - if (cpu_online(cpu) || !cpu_present(cpu)) - return -EINVAL; - cpu_hotplug_begin(); + if (cpu_online(cpu) || !cpu_present(cpu)) { + ret = -EINVAL; + goto out; + } + idle = idle_thread_get(cpu); if (IS_ERR(idle)) { ret = PTR_ERR(idle); diff --git a/kernel/futex.c b/kernel/futex.c index 3717e7b306e0..20ef219bbe9b 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -716,7 +716,7 @@ static int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb, struct futex_pi_state **ps, struct task_struct *task, int set_waiters) { - int lock_taken, ret, ownerdied = 0; + int lock_taken, ret, force_take = 0; u32 uval, newval, curval, vpid = task_pid_vnr(task); retry: @@ -755,17 +755,15 @@ retry: newval = curval | FUTEX_WAITERS; /* - * There are two cases, where a futex might have no owner (the - * owner TID is 0): OWNER_DIED. We take over the futex in this - * case. We also do an unconditional take over, when the owner - * of the futex died. - * - * This is safe as we are protected by the hash bucket lock ! + * Should we force take the futex? See below. */ - if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { - /* Keep the OWNER_DIED bit */ + if (unlikely(force_take)) { + /* + * Keep the OWNER_DIED and the WAITERS bit and set the + * new TID value. + */ newval = (curval & ~FUTEX_TID_MASK) | vpid; - ownerdied = 0; + force_take = 0; lock_taken = 1; } @@ -775,7 +773,7 @@ retry: goto retry; /* - * We took the lock due to owner died take over. + * We took the lock due to forced take over. */ if (unlikely(lock_taken)) return 1; @@ -790,20 +788,25 @@ retry: switch (ret) { case -ESRCH: /* - * No owner found for this futex. Check if the - * OWNER_DIED bit is set to figure out whether - * this is a robust futex or not. + * We failed to find an owner for this + * futex. So we have no pi_state to block + * on. This can happen in two cases: + * + * 1) The owner died + * 2) A stale FUTEX_WAITERS bit + * + * Re-read the futex value. */ if (get_futex_value_locked(&curval, uaddr)) return -EFAULT; /* - * We simply start over in case of a robust - * futex. The code above will take the futex - * and return happy. + * If the owner died or we have a stale + * WAITERS bit the owner TID in the user space + * futex is 0. */ - if (curval & FUTEX_OWNER_DIED) { - ownerdied = 1; + if (!(curval & FUTEX_TID_MASK)) { + force_take = 1; goto retry; } default: diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 4da05cee81bf..9322ff7eaad6 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -213,6 +213,69 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, } /** + * pm_qos_flags_remove_req - Remove device PM QoS flags request. + * @pqf: Device PM QoS flags set to remove the request from. + * @req: Request to remove from the set. + */ +static void pm_qos_flags_remove_req(struct pm_qos_flags *pqf, + struct pm_qos_flags_request *req) +{ + s32 val = 0; + + list_del(&req->node); + list_for_each_entry(req, &pqf->list, node) + val |= req->flags; + + pqf->effective_flags = val; +} + +/** + * pm_qos_update_flags - Update a set of PM QoS flags. + * @pqf: Set of flags to update. + * @req: Request to add to the set, to modify, or to remove from the set. + * @action: Action to take on the set. + * @val: Value of the request to add or modify. + * + * Update the given set of PM QoS flags and call notifiers if the aggregate + * value has changed. Returns 1 if the aggregate constraint value has changed, + * 0 otherwise. + */ +bool pm_qos_update_flags(struct pm_qos_flags *pqf, + struct pm_qos_flags_request *req, + enum pm_qos_req_action action, s32 val) +{ + unsigned long irqflags; + s32 prev_value, curr_value; + + spin_lock_irqsave(&pm_qos_lock, irqflags); + + prev_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags; + + switch (action) { + case PM_QOS_REMOVE_REQ: + pm_qos_flags_remove_req(pqf, req); + break; + case PM_QOS_UPDATE_REQ: + pm_qos_flags_remove_req(pqf, req); + case PM_QOS_ADD_REQ: + req->flags = val; + INIT_LIST_HEAD(&req->node); + list_add_tail(&req->node, &pqf->list); + pqf->effective_flags |= val; + break; + default: + /* no action */ + ; + } + + curr_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags; + + spin_unlock_irqrestore(&pm_qos_lock, irqflags); + + return prev_value != curr_value; +} + +/** * pm_qos_request - returns current system wide qos expectation * @pm_qos_class: identification of which qos value is requested * diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index a40260885265..6f337068dc4c 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -526,6 +526,8 @@ void tick_nohz_irq_exit(void) if (!ts->inidle) return; + /* Cancel the timer because CPU already waken up from the C-states*/ + menu_hrtimer_cancel(); __tick_nohz_idle_enter(ts); } @@ -621,6 +623,8 @@ void tick_nohz_idle_exit(void) ts->inidle = 0; + /* Cancel the timer because CPU already waken up from the C-states*/ + menu_hrtimer_cancel(); if (ts->idle_active || ts->tick_stopped) now = ktime_get(); |