diff options
Diffstat (limited to 'kernel')
37 files changed, 737 insertions, 400 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 972f8e61d36..59cedfb040e 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -243,10 +243,11 @@ static inline int open_arg(int flags, int mask) static int audit_match_perm(struct audit_context *ctx, int mask) { + unsigned n; if (unlikely(!ctx)) return 0; - unsigned n = ctx->major; + n = ctx->major; switch (audit_classify_syscall(ctx->arch, n)) { case 0: /* native */ if ((mask & AUDIT_PERM_WRITE) && diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 13932abde15..a0123d75ec9 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2738,14 +2738,15 @@ void cgroup_fork_callbacks(struct task_struct *child) */ void cgroup_mm_owner_callbacks(struct task_struct *old, struct task_struct *new) { - struct cgroup *oldcgrp, *newcgrp; + struct cgroup *oldcgrp, *newcgrp = NULL; if (need_mm_owner_callback) { int i; for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { struct cgroup_subsys *ss = subsys[i]; oldcgrp = task_cgroup(old, ss->subsys_id); - newcgrp = task_cgroup(new, ss->subsys_id); + if (new) + newcgrp = task_cgroup(new, ss->subsys_id); if (oldcgrp == newcgrp) continue; if (ss->mm_owner_changed) diff --git a/kernel/cpuset.c b/kernel/cpuset.c index d5ab79cf516..827cd9adccb 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -14,6 +14,8 @@ * 2003-10-22 Updates by Stephen Hemminger. * 2004 May-July Rework by Paul Jackson. * 2006 Rework by Paul Menage to use generic cgroups + * 2008 Rework of the scheduler domains and CPU hotplug handling + * by Max Krasnyansky * * This file is subject to the terms and conditions of the GNU General Public * License. See the file COPYING in the main directory of the Linux @@ -236,9 +238,11 @@ static struct cpuset top_cpuset = { static DEFINE_MUTEX(callback_mutex); -/* This is ugly, but preserves the userspace API for existing cpuset +/* + * This is ugly, but preserves the userspace API for existing cpuset * users. If someone tries to mount the "cpuset" filesystem, we - * silently switch it to mount "cgroup" instead */ + * silently switch it to mount "cgroup" instead + */ static int cpuset_get_sb(struct file_system_type *fs_type, int flags, const char *unused_dev_name, void *data, struct vfsmount *mnt) @@ -473,10 +477,9 @@ static int validate_change(const struct cpuset *cur, const struct cpuset *trial) } /* - * Helper routine for rebuild_sched_domains(). + * Helper routine for generate_sched_domains(). * Do cpusets a, b have overlapping cpus_allowed masks? */ - static int cpusets_overlap(struct cpuset *a, struct cpuset *b) { return cpus_intersects(a->cpus_allowed, b->cpus_allowed); @@ -518,26 +521,15 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) } /* - * rebuild_sched_domains() - * - * This routine will be called to rebuild the scheduler's dynamic - * sched domains: - * - if the flag 'sched_load_balance' of any cpuset with non-empty - * 'cpus' changes, - * - or if the 'cpus' allowed changes in any cpuset which has that - * flag enabled, - * - or if the 'sched_relax_domain_level' of any cpuset which has - * that flag enabled and with non-empty 'cpus' changes, - * - or if any cpuset with non-empty 'cpus' is removed, - * - or if a cpu gets offlined. - * - * This routine builds a partial partition of the systems CPUs - * (the set of non-overlappping cpumask_t's in the array 'part' - * below), and passes that partial partition to the kernel/sched.c - * partition_sched_domains() routine, which will rebuild the - * schedulers load balancing domains (sched domains) as specified - * by that partial partition. A 'partial partition' is a set of - * non-overlapping subsets whose union is a subset of that set. + * generate_sched_domains() + * + * This function builds a partial partition of the systems CPUs + * A 'partial partition' is a set of non-overlapping subsets whose + * union is a subset of that set. + * The output of this function needs to be passed to kernel/sched.c + * partition_sched_domains() routine, which will rebuild the scheduler's + * load balancing domains (sched domains) as specified by that partial + * partition. * * See "What is sched_load_balance" in Documentation/cpusets.txt * for a background explanation of this. @@ -547,13 +539,7 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) * domains when operating in the severe memory shortage situations * that could cause allocation failures below. * - * Call with cgroup_mutex held. May take callback_mutex during - * call due to the kfifo_alloc() and kmalloc() calls. May nest - * a call to the get_online_cpus()/put_online_cpus() pair. - * Must not be called holding callback_mutex, because we must not - * call get_online_cpus() while holding callback_mutex. Elsewhere - * the kernel nests callback_mutex inside get_online_cpus() calls. - * So the reverse nesting would risk an ABBA deadlock. + * Must be called with cgroup_lock held. * * The three key local variables below are: * q - a linked-list queue of cpuset pointers, used to implement a @@ -588,10 +574,10 @@ update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c) * element of the partition (one sched domain) to be passed to * partition_sched_domains(). */ - -void rebuild_sched_domains(void) +static int generate_sched_domains(cpumask_t **domains, + struct sched_domain_attr **attributes) { - LIST_HEAD(q); /* queue of cpusets to be scanned*/ + LIST_HEAD(q); /* queue of cpusets to be scanned */ struct cpuset *cp; /* scans q */ struct cpuset **csa; /* array of all cpuset ptrs */ int csn; /* how many cpuset ptrs in csa so far */ @@ -601,23 +587,26 @@ void rebuild_sched_domains(void) int ndoms; /* number of sched domains in result */ int nslot; /* next empty doms[] cpumask_t slot */ - csa = NULL; + ndoms = 0; doms = NULL; dattr = NULL; + csa = NULL; /* Special case for the 99% of systems with one, full, sched domain */ if (is_sched_load_balance(&top_cpuset)) { - ndoms = 1; doms = kmalloc(sizeof(cpumask_t), GFP_KERNEL); if (!doms) - goto rebuild; + goto done; + dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL); if (dattr) { *dattr = SD_ATTR_INIT; update_domain_attr_tree(dattr, &top_cpuset); } *doms = top_cpuset.cpus_allowed; - goto rebuild; + + ndoms = 1; + goto done; } csa = kmalloc(number_of_cpusets * sizeof(cp), GFP_KERNEL); @@ -680,61 +669,141 @@ restart: } } - /* Convert <csn, csa> to <ndoms, doms> */ + /* + * Now we know how many domains to create. + * Convert <csn, csa> to <ndoms, doms> and populate cpu masks. + */ doms = kmalloc(ndoms * sizeof(cpumask_t), GFP_KERNEL); - if (!doms) - goto rebuild; + if (!doms) { + ndoms = 0; + goto done; + } + + /* + * The rest of the code, including the scheduler, can deal with + * dattr==NULL case. No need to abort if alloc fails. + */ dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL); for (nslot = 0, i = 0; i < csn; i++) { struct cpuset *a = csa[i]; + cpumask_t *dp; int apn = a->pn; - if (apn >= 0) { - cpumask_t *dp = doms + nslot; - - if (nslot == ndoms) { - static int warnings = 10; - if (warnings) { - printk(KERN_WARNING - "rebuild_sched_domains confused:" - " nslot %d, ndoms %d, csn %d, i %d," - " apn %d\n", - nslot, ndoms, csn, i, apn); - warnings--; - } - continue; + if (apn < 0) { + /* Skip completed partitions */ + continue; + } + + dp = doms + nslot; + + if (nslot == ndoms) { + static int warnings = 10; + if (warnings) { + printk(KERN_WARNING + "rebuild_sched_domains confused:" + " nslot %d, ndoms %d, csn %d, i %d," + " apn %d\n", + nslot, ndoms, csn, i, apn); + warnings--; } + continue; + } - cpus_clear(*dp); - if (dattr) - *(dattr + nslot) = SD_ATTR_INIT; - for (j = i; j < csn; j++) { - struct cpuset *b = csa[j]; - - if (apn == b->pn) { - cpus_or(*dp, *dp, b->cpus_allowed); - b->pn = -1; - if (dattr) - update_domain_attr_tree(dattr - + nslot, b); - } + cpus_clear(*dp); + if (dattr) + *(dattr + nslot) = SD_ATTR_INIT; + for (j = i; j < csn; j++) { + struct cpuset *b = csa[j]; + + if (apn == b->pn) { + cpus_or(*dp, *dp, b->cpus_allowed); + if (dattr) + update_domain_attr_tree(dattr + nslot, b); + + /* Done with this partition */ + b->pn = -1; } - nslot++; } + nslot++; } BUG_ON(nslot != ndoms); -rebuild: - /* Have scheduler rebuild sched domains */ +done: + kfree(csa); + + *domains = doms; + *attributes = dattr; + return ndoms; +} + +/* + * Rebuild scheduler domains. + * + * Call with neither cgroup_mutex held nor within get_online_cpus(). + * Takes both cgroup_mutex and get_online_cpus(). + * + * Cannot be directly called from cpuset code handling changes + * to the cpuset pseudo-filesystem, because it cannot be called + * from code that already holds cgroup_mutex. + */ +static void do_rebuild_sched_domains(struct work_struct *unused) +{ + struct sched_domain_attr *attr; + cpumask_t *doms; + int ndoms; + get_online_cpus(); - partition_sched_domains(ndoms, doms, dattr); + + /* Generate domain masks and attrs */ + cgroup_lock(); + ndoms = generate_sched_domains(&doms, &attr); + cgroup_unlock(); + + /* Have scheduler rebuild the domains */ + partition_sched_domains(ndoms, doms, attr); + put_online_cpus(); +} -done: - kfree(csa); - /* Don't kfree(doms) -- partition_sched_domains() does that. */ - /* Don't kfree(dattr) -- partition_sched_domains() does that. */ +static DECLARE_WORK(rebuild_sched_domains_work, do_rebuild_sched_domains); + +/* + * Rebuild scheduler domains, asynchronously via workqueue. + * + * If the flag 'sched_load_balance' of any cpuset with non-empty + * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset + * which has that flag enabled, or if any cpuset with a non-empty + * 'cpus' is removed, then call this routine to rebuild the + * scheduler's dynamic sched domains. + * + * The rebuild_sched_domains() and partition_sched_domains() + * routines must nest cgroup_lock() inside get_online_cpus(), + * but such cpuset changes as these must nest that locking the + * other way, holding cgroup_lock() for much of the code. + * + * So in order to avoid an ABBA deadlock, the cpuset code handling + * these user changes delegates the actual sched domain rebuilding + * to a separate workqueue thread, which ends up processing the + * above do_rebuild_sched_domains() function. + */ +static void async_rebuild_sched_domains(void) +{ + schedule_work(&rebuild_sched_domains_work); +} + +/* + * Accomplishes the same scheduler domain rebuild as the above + * async_rebuild_sched_domains(), however it directly calls the + * rebuild routine synchronously rather than calling it via an + * asynchronous work thread. + * + * This can only be called from code that is not holding + * cgroup_mutex (not nested in a cgroup_lock() call.) + */ +void rebuild_sched_domains(void) +{ + do_rebuild_sched_domains(NULL); } /** @@ -774,37 +843,25 @@ static void cpuset_change_cpumask(struct task_struct *tsk, /** * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset. * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed + * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks() * * Called with cgroup_mutex held * * The cgroup_scan_tasks() function will scan all the tasks in a cgroup, * calling callback functions for each. * - * Return 0 if successful, -errno if not. + * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0 + * if @heap != NULL. */ -static int update_tasks_cpumask(struct cpuset *cs) +static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap) { struct cgroup_scanner scan; - struct ptr_heap heap; - int retval; - - /* - * cgroup_scan_tasks() will initialize heap->gt for us. - * heap_init() is still needed here for we should not change - * cs->cpus_allowed when heap_init() fails. - */ - retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); - if (retval) - return retval; scan.cg = cs->css.cgroup; scan.test_task = cpuset_test_cpumask; scan.process_task = cpuset_change_cpumask; - scan.heap = &heap; - retval = cgroup_scan_tasks(&scan); - - heap_free(&heap); - return retval; + scan.heap = heap; + cgroup_scan_tasks(&scan); } /** @@ -814,6 +871,7 @@ static int update_tasks_cpumask(struct cpuset *cs) */ static int update_cpumask(struct cpuset *cs, const char *buf) { + struct ptr_heap heap; struct cpuset trialcs; int retval; int is_load_balanced; @@ -848,6 +906,10 @@ static int update_cpumask(struct cpuset *cs, const char *buf) if (cpus_equal(cs->cpus_allowed, trialcs.cpus_allowed)) return 0; + retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL); + if (retval) + return retval; + is_load_balanced = is_sched_load_balance(&trialcs); mutex_lock(&callback_mutex); @@ -858,12 +920,12 @@ static int update_cpumask(struct cpuset *cs, const char *buf) * Scan tasks in the cpuset, and update the cpumasks of any * that need an update. */ - retval = update_tasks_cpumask(cs); - if (retval < 0) - return retval; + update_tasks_cpumask(cs, &heap); + + heap_free(&heap); if (is_load_balanced) - rebuild_sched_domains(); + async_rebuild_sched_domains(); return 0; } @@ -1090,7 +1152,7 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val) if (val != cs->relax_domain_level) { cs->relax_domain_level = val; if (!cpus_empty(cs->cpus_allowed) && is_sched_load_balance(cs)) - rebuild_sched_domains(); + async_rebuild_sched_domains(); } return 0; @@ -1131,7 +1193,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, mutex_unlock(&callback_mutex); if (cpus_nonempty && balance_flag_changed) - rebuild_sched_domains(); + async_rebuild_sched_domains(); return 0; } @@ -1492,6 +1554,9 @@ static u64 cpuset_read_u64(struct cgroup *cont, struct cftype *cft) default: BUG(); } + + /* Unreachable but makes gcc happy */ + return 0; } static s64 cpuset_read_s64(struct cgroup *cont, struct cftype *cft) @@ -1504,6 +1569,9 @@ static s64 cpuset_read_s64(struct cgroup *cont, struct cftype *cft) default: BUG(); } + + /* Unrechable but makes gcc happy */ + return 0; } @@ -1692,15 +1760,9 @@ static struct cgroup_subsys_state *cpuset_create( } /* - * Locking note on the strange update_flag() call below: - * * If the cpuset being removed has its flag 'sched_load_balance' * enabled, then simulate turning sched_load_balance off, which - * will call rebuild_sched_domains(). The get_online_cpus() - * call in rebuild_sched_domains() must not be made while holding - * callback_mutex. Elsewhere the kernel nests callback_mutex inside - * get_online_cpus() calls. So the reverse nesting would risk an - * ABBA deadlock. + * will call async_rebuild_sched_domains(). */ static void cpuset_destroy(struct cgroup_subsys *ss, struct cgroup *cont) @@ -1719,7 +1781,7 @@ static void cpuset_destroy(struct cgroup_subsys *ss, struct cgroup *cont) struct cgroup_subsys cpuset_subsys = { .name = "cpuset", .create = cpuset_create, - .destroy = cpuset_destroy, + .destroy = cpuset_destroy, .can_attach = cpuset_can_attach, .attach = cpuset_attach, .populate = cpuset_populate, @@ -1811,7 +1873,7 @@ static void move_member_tasks_to_cpuset(struct cpuset *from, struct cpuset *to) } /* - * If common_cpu_mem_hotplug_unplug(), below, unplugs any CPUs + * If CPU and/or memory hotplug handlers, below, unplug any CPUs * or memory nodes, we need to walk over the cpuset hierarchy, * removing that CPU or node from all cpusets. If this removes the * last CPU or node from a cpuset, then move the tasks in the empty @@ -1896,42 +1958,13 @@ static void scan_for_empty_cpusets(const struct cpuset *root) nodes_empty(cp->mems_allowed)) remove_tasks_in_empty_cpuset(cp); else { - update_tasks_cpumask(cp); + update_tasks_cpumask(cp, NULL); update_tasks_nodemask(cp, &oldmems); } } } /* - * The cpus_allowed and mems_allowed nodemasks in the top_cpuset track - * cpu_online_map and node_states[N_HIGH_MEMORY]. Force the top cpuset to - * track what's online after any CPU or memory node hotplug or unplug event. - * - * Since there are two callers of this routine, one for CPU hotplug - * events and one for memory node hotplug events, we could have coded - * two separate routines here. We code it as a single common routine - * in order to minimize text size. - */ - -static void common_cpu_mem_hotplug_unplug(int rebuild_sd) -{ - cgroup_lock(); - - top_cpuset.cpus_allowed = cpu_online_map; - top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; - scan_for_empty_cpusets(&top_cpuset); - - /* - * Scheduler destroys domains on hotplug events. - * Rebuild them based on the current settings. - */ - if (rebuild_sd) - rebuild_sched_domains(); - - cgroup_unlock(); -} - -/* * The top_cpuset tracks what CPUs and Memory Nodes are online, * period. This is necessary in order to make cpusets transparent * (of no affect) on systems that are actively using CPU hotplug @@ -1939,40 +1972,52 @@ static void common_cpu_mem_hotplug_unplug(int rebuild_sd) * * This routine ensures that top_cpuset.cpus_allowed tracks * cpu_online_map on each CPU hotplug (cpuhp) event. + * + * Called within get_online_cpus(). Needs to call cgroup_lock() + * before calling generate_sched_domains(). */ - -static int cpuset_handle_cpuhp(struct notifier_block *unused_nb, +static int cpuset_track_online_cpus(struct notifier_block *unused_nb, unsigned long phase, void *unused_cpu) { + struct sched_domain_attr *attr; + cpumask_t *doms; + int ndoms; + switch (phase) { - case CPU_UP_CANCELED: - case CPU_UP_CANCELED_FROZEN: - case CPU_DOWN_FAILED: - case CPU_DOWN_FAILED_FROZEN: case CPU_ONLINE: case CPU_ONLINE_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: - common_cpu_mem_hotplug_unplug(1); break; + default: return NOTIFY_DONE; } + cgroup_lock(); + top_cpuset.cpus_allowed = cpu_online_map; + scan_for_empty_cpusets(&top_cpuset); + ndoms = generate_sched_domains(&doms, &attr); + cgroup_unlock(); + + /* Have scheduler rebuild the domains */ + partition_sched_domains(ndoms, doms, attr); + return NOTIFY_OK; } #ifdef CONFIG_MEMORY_HOTPLUG /* * Keep top_cpuset.mems_allowed tracking node_states[N_HIGH_MEMORY]. - * Call this routine anytime after you change - * node_states[N_HIGH_MEMORY]. - * See also the previous routine cpuset_handle_cpuhp(). + * Call this routine anytime after node_states[N_HIGH_MEMORY] changes. + * See also the previous routine cpuset_track_online_cpus(). */ - void cpuset_track_online_nodes(void) { - common_cpu_mem_hotplug_unplug(0); + cgroup_lock(); + top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; + scan_for_empty_cpusets(&top_cpuset); + cgroup_unlock(); } #endif @@ -1987,7 +2032,7 @@ void __init cpuset_init_smp(void) top_cpuset.cpus_allowed = cpu_online_map; top_cpuset.mems_allowed = node_states[N_HIGH_MEMORY]; - hotcpu_notifier(cpuset_handle_cpuhp, 0); + hotcpu_notifier(cpuset_track_online_cpus, 0); } /** diff --git a/kernel/exit.c b/kernel/exit.c index 38ec4063014..85a83c83185 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -112,9 +112,9 @@ static void __exit_signal(struct task_struct *tsk) * We won't ever get here for the group leader, since it * will have been the last reference on the signal_struct. */ - sig->utime = cputime_add(sig->utime, tsk->utime); - sig->stime = cputime_add(sig->stime, tsk->stime); - sig->gtime = cputime_add(sig->gtime, tsk->gtime); + sig->utime = cputime_add(sig->utime, task_utime(tsk)); + sig->stime = cputime_add(sig->stime, task_stime(tsk)); + sig->gtime = cputime_add(sig->gtime, task_gtime(tsk)); sig->min_flt += tsk->min_flt; sig->maj_flt += tsk->maj_flt; sig->nvcsw += tsk->nvcsw; @@ -583,8 +583,6 @@ mm_need_new_owner(struct mm_struct *mm, struct task_struct *p) * If there are other users of the mm and the owner (us) is exiting * we need to find a new owner to take on the responsibility. */ - if (!mm) - return 0; if (atomic_read(&mm->mm_users) <= 1) return 0; if (mm->owner != p) @@ -627,6 +625,16 @@ retry: } while_each_thread(g, c); read_unlock(&tasklist_lock); + /* + * We found no owner yet mm_users > 1: this implies that we are + * most likely racing with swapoff (try_to_unuse()) or /proc or + * ptrace or page migration (get_task_mm()). Mark owner as NULL, + * so that subsystems can understand the callback and take action. + */ + down_write(&mm->mmap_sem); + cgroup_mm_owner_callbacks(mm->owner, NULL); + mm->owner = NULL; + up_write(&mm->mmap_sem); return; assign_new_owner: @@ -831,26 +839,50 @@ static void reparent_thread(struct task_struct *p, struct task_struct *father) * the child reaper process (ie "init") in our pid * space. */ +static struct task_struct *find_new_reaper(struct task_struct *father) +{ + struct pid_namespace *pid_ns = task_active_pid_ns(father); + struct task_struct *thread; + + thread = father; + while_each_thread(father, thread) { + if (thread->flags & PF_EXITING) + continue; + if (unlikely(pid_ns->child_reaper == father)) + pid_ns->child_reaper = thread; + return thread; + } + + if (unlikely(pid_ns->child_reaper == father)) { + write_unlock_irq(&tasklist_lock); + if (unlikely(pid_ns == &init_pid_ns)) + panic("Attempted to kill init!"); + + zap_pid_ns_processes(pid_ns); + write_lock_irq(&tasklist_lock); + /* + * We can not clear ->child_reaper or leave it alone. + * There may by stealth EXIT_DEAD tasks on ->children, + * forget_original_parent() must move them somewhere. + */ + pid_ns->child_reaper = init_pid_ns.child_reaper; + } + + return pid_ns->child_reaper; +} + static void forget_original_parent(struct task_struct *father) { - struct task_struct *p, *n, *reaper = father; + struct task_struct *p, *n, *reaper; LIST_HEAD(ptrace_dead); write_lock_irq(&tasklist_lock); - + reaper = find_new_reaper(father); /* * First clean up ptrace if we were using it. */ ptrace_exit(father, &ptrace_dead); - do { - reaper = next_thread(reaper); - if (reaper == father) { - reaper = task_child_reaper(father); - break; - } - } while (reaper->flags & PF_EXITING); - list_for_each_entry_safe(p, n, &father->children, sibling) { p->real_parent = reaper; if (p->parent == father) { @@ -918,8 +950,8 @@ static void exit_notify(struct task_struct *tsk, int group_dead) /* mt-exec, de_thread() is waiting for us */ if (thread_group_leader(tsk) && - tsk->signal->notify_count < 0 && - tsk->signal->group_exit_task) + tsk->signal->group_exit_task && + tsk->signal->notify_count < 0) wake_up_process(tsk->signal->group_exit_task); write_unlock_irq(&tasklist_lock); @@ -959,39 +991,6 @@ static void check_stack_usage(void) static inline void check_stack_usage(void) {} #endif -static inline void exit_child_reaper(struct task_struct *tsk) -{ - if (likely(tsk->group_leader != task_child_reaper(tsk))) - return; - - if (tsk->nsproxy->pid_ns == &init_pid_ns) - panic("Attempted to kill init!"); - - /* - * @tsk is the last thread in the 'cgroup-init' and is exiting. - * Terminate all remaining processes in the namespace and reap them - * before exiting @tsk. - * - * Note that @tsk (last thread of cgroup-init) may not necessarily - * be the child-reaper (i.e main thread of cgroup-init) of the - * namespace i.e the child_reaper may have already exited. - * - * Even after a child_reaper exits, we let it inherit orphaned children, - * because, pid_ns->child_reaper remains valid as long as there is - * at least one living sub-thread in the cgroup init. - - * This living sub-thread of the cgroup-init will be notified when - * a child inherited by the 'child-reaper' exits (do_notify_parent() - * uses __group_send_sig_info()). Further, when reaping child processes, - * do_wait() iterates over children of all living sub threads. - - * i.e even though 'child_reaper' thread is listed as the parent of the - * orphaned children, any living sub-thread in the cgroup-init can - * perform the role of the child_reaper. - */ - zap_pid_ns_processes(tsk->nsproxy->pid_ns); -} - NORET_TYPE void do_exit(long code) { struct task_struct *tsk = current; @@ -1051,7 +1050,6 @@ NORET_TYPE void do_exit(long code) } group_dead = atomic_dec_and_test(&tsk->signal->live); if (group_dead) { - exit_child_reaper(tsk); hrtimer_cancel(&tsk->signal->real_timer); exit_itimers(tsk->signal); } diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index b8e4dce80a7..cdec83e722f 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -672,13 +672,14 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, */ BUG_ON(timer->function(timer) != HRTIMER_NORESTART); return 1; - case HRTIMER_CB_IRQSAFE_NO_SOFTIRQ: + case HRTIMER_CB_IRQSAFE_PERCPU: + case HRTIMER_CB_IRQSAFE_UNLOCKED: /* * This is solely for the sched tick emulation with * dynamic tick support to ensure that we do not * restart the tick right on the edge and end up with * the tick timer in the softirq ! The calling site - * takes care of this. + * takes care of this. Also used for hrtimer sleeper ! */ debug_hrtimer_deactivate(timer); return 1; @@ -1245,7 +1246,8 @@ static void __run_hrtimer(struct hrtimer *timer) timer_stats_account_hrtimer(timer); fn = timer->function; - if (timer->cb_mode == HRTIMER_CB_IRQSAFE_NO_SOFTIRQ) { + if (timer->cb_mode == HRTIMER_CB_IRQSAFE_PERCPU || + timer->cb_mode == HRTIMER_CB_IRQSAFE_UNLOCKED) { /* * Used for scheduler timers, avoid lock inversion with * rq->lock and tasklist_lock. @@ -1452,7 +1454,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task) sl->timer.function = hrtimer_wakeup; sl->task = task; #ifdef CONFIG_HIGH_RES_TIMERS - sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED; #endif } @@ -1591,29 +1593,95 @@ static void __cpuinit init_hrtimers_cpu(int cpu) #ifdef CONFIG_HOTPLUG_CPU -static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base, - struct hrtimer_clock_base *new_base) +static int migrate_hrtimer_list(struct hrtimer_clock_base *old_base, + struct hrtimer_clock_base *new_base, int dcpu) { struct hrtimer *timer; struct rb_node *node; + int raise = 0; while ((node = rb_first(&old_base->active))) { timer = rb_entry(node, struct hrtimer, node); BUG_ON(hrtimer_callback_running(timer)); debug_hrtimer_deactivate(timer); - __remove_hrtimer(timer, old_base, HRTIMER_STATE_INACTIVE, 0); + + /* + * Should not happen. Per CPU timers should be + * canceled _before_ the migration code is called + */ + if (timer->cb_mode == HRTIMER_CB_IRQSAFE_PERCPU) { + __remove_hrtimer(timer, old_base, + HRTIMER_STATE_INACTIVE, 0); + WARN(1, "hrtimer (%p %p)active but cpu %d dead\n", + timer, timer->function, dcpu); + continue; + } + + /* + * Mark it as STATE_MIGRATE not INACTIVE otherwise the + * timer could be seen as !active and just vanish away + * under us on another CPU + */ + __remove_hrtimer(timer, old_base, HRTIMER_STATE_MIGRATE, 0); timer->base = new_base; /* * Enqueue the timer. Allow reprogramming of the event device */ enqueue_hrtimer(timer, new_base, 1); + +#ifdef CONFIG_HIGH_RES_TIMERS + /* + * Happens with high res enabled when the timer was + * already expired and the callback mode is + * HRTIMER_CB_IRQSAFE_UNLOCKED (hrtimer_sleeper). The + * enqueue code does not move them to the soft irq + * pending list for performance/latency reasons, but + * in the migration state, we need to do that + * otherwise we end up with a stale timer. + */ + if (timer->state == HRTIMER_STATE_MIGRATE) { + timer->state = HRTIMER_STATE_PENDING; + list_add_tail(&timer->cb_entry, + &new_base->cpu_base->cb_pending); + raise = 1; + } +#endif + /* Clear the migration state bit */ + timer->state &= ~HRTIMER_STATE_MIGRATE; + } + return raise; +} + +#ifdef CONFIG_HIGH_RES_TIMERS +static int migrate_hrtimer_pending(struct hrtimer_cpu_base *old_base, + struct hrtimer_cpu_base *new_base) +{ + struct hrtimer *timer; + int raise = 0; + + while (!list_empty(&old_base->cb_pending)) { + timer = list_entry(old_base->cb_pending.next, + struct hrtimer, cb_entry); + + __remove_hrtimer(timer, timer->base, HRTIMER_STATE_PENDING, 0); + timer->base = &new_base->clock_base[timer->base->index]; + list_add_tail(&timer->cb_entry, &new_base->cb_pending); + raise = 1; } + return raise; +} +#else +static int migrate_hrtimer_pending(struct hrtimer_cpu_base *old_base, + struct hrtimer_cpu_base *new_base) +{ + return 0; } +#endif static void migrate_hrtimers(int cpu) { struct hrtimer_cpu_base *old_base, *new_base; - int i; + int i, raise = 0; BUG_ON(cpu_online(cpu)); old_base = &per_cpu(hrtimer_bases, cpu); @@ -1626,14 +1694,21 @@ static void migrate_hrtimers(int cpu) spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING); for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { - migrate_hrtimer_list(&old_base->clock_base[i], - &new_base->clock_base[i]); + if (migrate_hrtimer_list(&old_base->clock_base[i], + &new_base->clock_base[i], cpu)) + raise = 1; } + if (migrate_hrtimer_pending(old_base, new_base)) + raise = 1; + spin_unlock(&old_base->lock); spin_unlock(&new_base->lock); local_irq_enable(); put_cpu_var(hrtimer_bases); + + if (raise) + hrtimer_raise_softirq(); } #endif /* CONFIG_HOTPLUG_CPU */ diff --git a/kernel/kexec.c b/kernel/kexec.c index 59f3f0df35d..aef265325cd 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -753,8 +753,14 @@ static struct page *kimage_alloc_page(struct kimage *image, *old = addr | (*old & ~PAGE_MASK); /* The old page I have found cannot be a - * destination page, so return it. + * destination page, so return it if it's + * gfp_flags honor the ones passed in. */ + if (!(gfp_mask & __GFP_HIGHMEM) && + PageHighMem(old_page)) { + kimage_free_pages(old_page); + continue; + } addr = old_addr; page = old_page; break; diff --git a/kernel/kgdb.c b/kernel/kgdb.c index eaa21fc9ad1..25d955dbb98 100644 --- a/kernel/kgdb.c +++ b/kernel/kgdb.c @@ -488,7 +488,7 @@ static int write_mem_msg(int binary) if (err) return err; if (CACHE_FLUSH_IS_SAFE) - flush_icache_range(addr, addr + length + 1); + flush_icache_range(addr, addr + length); return 0; } @@ -1462,7 +1462,7 @@ acquirelock: * Get the passive CPU lock which will hold all the non-primary * CPU in a spin state while the debugger is active */ - if (!kgdb_single_step || !kgdb_contthread) { + if (!kgdb_single_step) { for (i = 0; i < NR_CPUS; i++) atomic_set(&passive_cpu_wait[i], 1); } @@ -1475,7 +1475,7 @@ acquirelock: #ifdef CONFIG_SMP /* Signal the other CPUs to enter kgdb_wait() */ - if ((!kgdb_single_step || !kgdb_contthread) && kgdb_do_roundup) + if ((!kgdb_single_step) && kgdb_do_roundup) kgdb_roundup_cpus(flags); #endif @@ -1494,7 +1494,7 @@ acquirelock: kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code); kgdb_deactivate_sw_breakpoints(); kgdb_single_step = 0; - kgdb_contthread = NULL; + kgdb_contthread = current; exception_level = 0; /* Talk to debugger with gdbserial protocol */ @@ -1508,7 +1508,7 @@ acquirelock: kgdb_info[ks->cpu].task = NULL; atomic_set(&cpu_in_kgdb[ks->cpu], 0); - if (!kgdb_single_step || !kgdb_contthread) { + if (!kgdb_single_step) { for (i = NR_CPUS-1; i >= 0; i--) atomic_set(&passive_cpu_wait[i], 0); /* diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 3bfb1877a00..dbda475b13b 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -875,11 +875,11 @@ static int add_lock_to_list(struct lock_class *class, struct lock_class *this, if (!entry) return 0; - entry->class = this; - entry->distance = distance; if (!save_trace(&entry->trace)) return 0; + entry->class = this; + entry->distance = distance; /* * Since we never remove from the dependency list, the list can * be walked lockless by other CPUs, it's only allocation @@ -3029,7 +3029,7 @@ found_it: stats = get_lock_stats(hlock_class(hlock)); if (point < ARRAY_SIZE(stats->contention_point)) - stats->contention_point[i]++; + stats->contention_point[point]++; if (lock->cpu != smp_processor_id()) stats->bounces[bounce_contended + !!hlock->read]++; put_lock_stats(stats); diff --git a/kernel/lockdep_proc.c b/kernel/lockdep_proc.c index 4b194d34d77..20dbcbf9c7d 100644 --- a/kernel/lockdep_proc.c +++ b/kernel/lockdep_proc.c @@ -472,8 +472,9 @@ static void snprint_time(char *buf, size_t bufsiz, s64 nr) { unsigned long rem; + nr += 5; /* for display rounding */ rem = do_div(nr, 1000); /* XXX: do_div_signed */ - snprintf(buf, bufsiz, "%lld.%02d", (long long)nr, ((int)rem+5)/10); + snprintf(buf, bufsiz, "%lld.%02d", (long long)nr, (int)rem/10); } static void seq_time(struct seq_file *m, s64 time) diff --git a/kernel/module.c b/kernel/module.c index 08864d257eb..9db11911e04 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1799,7 +1799,7 @@ static void *module_alloc_update_bounds(unsigned long size) /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ -static struct module *load_module(void __user *umod, +static noinline struct module *load_module(void __user *umod, unsigned long len, const char __user *uargs) { diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index 21575fc46d0..1d3ef29a258 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -14,7 +14,6 @@ */ #include <linux/module.h> -#include <linux/version.h> #include <linux/nsproxy.h> #include <linux/init_task.h> #include <linux/mnt_namespace.h> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index ea567b78d1a..fab8ea86fac 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -179,9 +179,6 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) rc = sys_wait4(-1, NULL, __WALL, NULL); } while (rc != -ECHILD); - - /* Child reaper for the pid namespace is going away */ - pid_ns->child_reaper = NULL; acct_exit_ns(pid_ns); return; } diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c index da9c2dda6a4..dfdec524d1b 100644 --- a/kernel/pm_qos_params.c +++ b/kernel/pm_qos_params.c @@ -43,7 +43,7 @@ #include <linux/uaccess.h> /* - * locking rule: all changes to target_value or requirements or notifiers lists + * locking rule: all changes to requirements or notifiers lists * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock * held, taken with _irqsave. One lock to rule them all */ @@ -66,7 +66,7 @@ struct pm_qos_object { struct miscdevice pm_qos_power_miscdev; char *name; s32 default_value; - s32 target_value; + atomic_t target_value; s32 (*comparitor)(s32, s32); }; @@ -77,7 +77,7 @@ static struct pm_qos_object cpu_dma_pm_qos = { .notifiers = &cpu_dma_lat_notifier, .name = "cpu_dma_latency", .default_value = 2000 * USEC_PER_SEC, - .target_value = 2000 * USEC_PER_SEC, + .target_value = ATOMIC_INIT(2000 * USEC_PER_SEC), .comparitor = min_compare }; @@ -87,7 +87,7 @@ static struct pm_qos_object network_lat_pm_qos = { .notifiers = &network_lat_notifier, .name = "network_latency", .default_value = 2000 * USEC_PER_SEC, - .target_value = 2000 * USEC_PER_SEC, + .target_value = ATOMIC_INIT(2000 * USEC_PER_SEC), .comparitor = min_compare }; @@ -99,7 +99,7 @@ static struct pm_qos_object network_throughput_pm_qos = { .notifiers = &network_throughput_notifier, .name = "network_throughput", .default_value = 0, - .target_value = 0, + .target_value = ATOMIC_INIT(0), .comparitor = max_compare }; @@ -150,11 +150,11 @@ static void update_target(int target) extreme_value = pm_qos_array[target]->comparitor( extreme_value, node->value); } - if (pm_qos_array[target]->target_value != extreme_value) { + if (atomic_read(&pm_qos_array[target]->target_value) != extreme_value) { call_notifier = 1; - pm_qos_array[target]->target_value = extreme_value; + atomic_set(&pm_qos_array[target]->target_value, extreme_value); pr_debug(KERN_ERR "new target for qos %d is %d\n", target, - pm_qos_array[target]->target_value); + atomic_read(&pm_qos_array[target]->target_value)); } spin_unlock_irqrestore(&pm_qos_lock, flags); @@ -193,14 +193,7 @@ static int find_pm_qos_object_by_minor(int minor) */ int pm_qos_requirement(int pm_qos_class) { - int ret_val; - unsigned long flags; - - spin_lock_irqsave(&pm_qos_lock, flags); - ret_val = pm_qos_array[pm_qos_class]->target_value; - spin_unlock_irqrestore(&pm_qos_lock, flags); - - return ret_val; + return atomic_read(&pm_qos_array[pm_qos_class]->target_value); } EXPORT_SYMBOL_GPL(pm_qos_requirement); diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index e36d5798cbf..5131e547116 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -441,7 +441,7 @@ static struct k_itimer * alloc_posix_timer(void) return tmr; if (unlikely(!(tmr->sigq = sigqueue_alloc()))) { kmem_cache_free(posix_timers_cache, tmr); - tmr = NULL; + return NULL; } memset(&tmr->sigq->info, 0, sizeof(siginfo_t)); return tmr; diff --git a/kernel/power/disk.c b/kernel/power/disk.c index f011e0870b5..bbd85c60f74 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -21,6 +21,7 @@ #include <linux/console.h> #include <linux/cpu.h> #include <linux/freezer.h> +#include <linux/ftrace.h> #include "power.h" @@ -255,7 +256,7 @@ static int create_image(int platform_mode) int hibernation_snapshot(int platform_mode) { - int error; + int error, ftrace_save; /* Free memory before shutting down devices. */ error = swsusp_shrink_memory(); @@ -267,6 +268,7 @@ int hibernation_snapshot(int platform_mode) goto Close; suspend_console(); + ftrace_save = __ftrace_enabled_save(); error = device_suspend(PMSG_FREEZE); if (error) goto Recover_platform; @@ -296,6 +298,7 @@ int hibernation_snapshot(int platform_mode) Resume_devices: device_resume(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); + __ftrace_enabled_restore(ftrace_save); resume_console(); Close: platform_end(platform_mode); @@ -366,10 +369,11 @@ static int resume_target_kernel(void) int hibernation_restore(int platform_mode) { - int error; + int error, ftrace_save; pm_prepare_console(); suspend_console(); + ftrace_save = __ftrace_enabled_save(); error = device_suspend(PMSG_QUIESCE); if (error) goto Finish; @@ -384,6 +388,7 @@ int hibernation_restore(int platform_mode) platform_restore_cleanup(platform_mode); device_resume(PMSG_RECOVER); Finish: + __ftrace_enabled_restore(ftrace_save); resume_console(); pm_restore_console(); return error; @@ -396,7 +401,7 @@ int hibernation_restore(int platform_mode) int hibernation_platform_enter(void) { - int error; + int error, ftrace_save; if (!hibernation_ops) return -ENOSYS; @@ -411,6 +416,7 @@ int hibernation_platform_enter(void) goto Close; suspend_console(); + ftrace_save = __ftrace_enabled_save(); error = device_suspend(PMSG_HIBERNATE); if (error) { if (hibernation_ops->recover) @@ -445,6 +451,7 @@ int hibernation_platform_enter(void) hibernation_ops->finish(); Resume_devices: device_resume(PMSG_RESTORE); + __ftrace_enabled_restore(ftrace_save); resume_console(); Close: hibernation_ops->end(); diff --git a/kernel/power/main.c b/kernel/power/main.c index 0b7476f5d2a..540b16b6856 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -21,6 +21,7 @@ #include <linux/freezer.h> #include <linux/vmstat.h> #include <linux/syscalls.h> +#include <linux/ftrace.h> #include "power.h" @@ -310,7 +311,7 @@ static int suspend_enter(suspend_state_t state) */ int suspend_devices_and_enter(suspend_state_t state) { - int error; + int error, ftrace_save; if (!suspend_ops) return -ENOSYS; @@ -321,6 +322,7 @@ int suspend_devices_and_enter(suspend_state_t state) goto Close; } suspend_console(); + ftrace_save = __ftrace_enabled_save(); suspend_test_start(); error = device_suspend(PMSG_SUSPEND); if (error) { @@ -352,6 +354,7 @@ int suspend_devices_and_enter(suspend_state_t state) suspend_test_start(); device_resume(PMSG_RESUME); suspend_test_finish("resume devices"); + __ftrace_enabled_restore(ftrace_save); resume_console(); Close: if (suspend_ops->end) diff --git a/kernel/power/swap.c b/kernel/power/swap.c index a0abf9a463f..80ccac849e4 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -14,7 +14,6 @@ #include <linux/module.h> #include <linux/file.h> #include <linux/utsname.h> -#include <linux/version.h> #include <linux/delay.h> #include <linux/bitops.h> #include <linux/genhd.h> diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index f14f372cf6f..467d5940f62 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -77,6 +77,7 @@ void wakeme_after_rcu(struct rcu_head *head) * sections are delimited by rcu_read_lock() and rcu_read_unlock(), * and may be nested. */ +void synchronize_rcu(void); /* Makes kernel-doc tools happy */ synchronize_rcu_xxx(synchronize_rcu, call_rcu) EXPORT_SYMBOL_GPL(synchronize_rcu); diff --git a/kernel/resource.c b/kernel/resource.c index f5b518eabef..03d796c1b2e 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -362,35 +362,21 @@ int allocate_resource(struct resource *root, struct resource *new, EXPORT_SYMBOL(allocate_resource); -/** - * insert_resource - Inserts a resource in the resource tree - * @parent: parent of the new resource - * @new: new resource to insert - * - * Returns 0 on success, -EBUSY if the resource can't be inserted. - * - * This function is equivalent to request_resource when no conflict - * happens. If a conflict happens, and the conflicting resources - * entirely fit within the range of the new resource, then the new - * resource is inserted and the conflicting resources become children of - * the new resource. +/* + * Insert a resource into the resource tree. If successful, return NULL, + * otherwise return the conflicting resource (compare to __request_resource()) */ -int insert_resource(struct resource *parent, struct resource *new) +static struct resource * __insert_resource(struct resource *parent, struct resource *new) { - int result; struct resource *first, *next; - write_lock(&resource_lock); - for (;; parent = first) { - result = 0; first = __request_resource(parent, new); if (!first) - goto out; + return first; - result = -EBUSY; if (first == parent) - goto out; + return first; if ((first->start > new->start) || (first->end < new->end)) break; @@ -401,15 +387,13 @@ int insert_resource(struct resource *parent, struct resource *new) for (next = first; ; next = next->sibling) { /* Partial overlap? Bad, and unfixable */ if (next->start < new->start || next->end > new->end) - goto out; + return next; if (!next->sibling) break; if (next->sibling->start > new->end) break; } - result = 0; - new->parent = parent; new->sibling = next->sibling; new->child = first; @@ -426,10 +410,64 @@ int insert_resource(struct resource *parent, struct resource *new) next = next->sibling; next->sibling = new; } + return NULL; +} - out: +/** + * insert_resource - Inserts a resource in the resource tree + * @parent: parent of the new resource + * @new: new resource to insert + * + * Returns 0 on success, -EBUSY if the resource can't be inserted. + * + * This function is equivalent to request_resource when no conflict + * happens. If a conflict happens, and the conflicting resources + * entirely fit within the range of the new resource, then the new + * resource is inserted and the conflicting resources become children of + * the new resource. + */ +int insert_resource(struct resource *parent, struct resource *new) +{ + struct resource *conflict; + + write_lock(&resource_lock); + conflict = __insert_resource(parent, new); + write_unlock(&resource_lock); + return conflict ? -EBUSY : 0; +} + +/** + * insert_resource_expand_to_fit - Insert a resource into the resource tree + * @root: root resource descriptor + * @new: new resource to insert + * + * Insert a resource into the resource tree, possibly expanding it in order + * to make it encompass any conflicting resources. + */ +void insert_resource_expand_to_fit(struct resource *root, struct resource *new) +{ + if (new->parent) + return; + + write_lock(&resource_lock); + for (;;) { + struct resource *conflict; + + conflict = __insert_resource(root, new); + if (!conflict) + break; + if (conflict == root) + break; + + /* Ok, expand resource to cover the conflict, then try again .. */ + if (conflict->start < new->start) + new->start = conflict->start; + if (conflict->end > new->end) + new->end = conflict->end; + + printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); + } write_unlock(&resource_lock); - return result; } /** diff --git a/kernel/sched.c b/kernel/sched.c index 9a1ddb84e26..ad1962dc0aa 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -201,7 +201,7 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime) hrtimer_init(&rt_b->rt_period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); rt_b->rt_period_timer.function = sched_rt_period_timer; - rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED; } static void start_rt_bandwidth(struct rt_bandwidth *rt_b) @@ -1087,7 +1087,7 @@ hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu) return NOTIFY_DONE; } -static void init_hrtick(void) +static __init void init_hrtick(void) { hotcpu_notifier(hotplug_hrtick, 0); } @@ -1119,7 +1119,7 @@ static void init_rq_hrtick(struct rq *rq) hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); rq->hrtick_timer.function = hrtick; - rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU; } #else static inline void hrtick_clear(struct rq *rq) @@ -4179,6 +4179,65 @@ void account_steal_time(struct task_struct *p, cputime_t steal) } /* + * Use precise platform statistics if available: + */ +#ifdef CONFIG_VIRT_CPU_ACCOUNTING +cputime_t task_utime(struct task_struct *p) +{ + return p->utime; +} + +cputime_t task_stime(struct task_struct *p) +{ + return p->stime; +} +#else +cputime_t task_utime(struct task_struct *p) +{ + clock_t utime = cputime_to_clock_t(p->utime), + total = utime + cputime_to_clock_t(p->stime); + u64 temp; + + /* + * Use CFS's precise accounting: + */ + temp = (u64)nsec_to_clock_t(p->se.sum_exec_runtime); + + if (total) { + temp *= utime; + do_div(temp, total); + } + utime = (clock_t)temp; + + p->prev_utime = max(p->prev_utime, clock_t_to_cputime(utime)); + return p->prev_utime; +} + +cputime_t task_stime(struct task_struct *p) +{ + clock_t stime; + + /* + * Use CFS's precise accounting. (we subtract utime from + * the total, to make sure the total observed by userspace + * grows monotonically - apps rely on that): + */ + stime = nsec_to_clock_t(p->se.sum_exec_runtime) - + cputime_to_clock_t(task_utime(p)); + + if (stime >= 0) + p->prev_stime = max(p->prev_stime, clock_t_to_cputime(stime)); + + return p->prev_stime; +} +#endif + +inline cputime_t task_gtime(struct task_struct *p) +{ + return p->gtime; +} + +/* * This function gets called by the timer code, with HZ frequency. * We call it with interrupts disabled. * @@ -7637,24 +7696,27 @@ static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, * and partition_sched_domains() will fallback to the single partition * 'fallback_doms', it also forces the domains to be rebuilt. * + * If doms_new==NULL it will be replaced with cpu_online_map. + * ndoms_new==0 is a special case for destroying existing domains. + * It will not create the default domain. + * * Call with hotplug lock held */ void partition_sched_domains(int ndoms_new, cpumask_t *doms_new, struct sched_domain_attr *dattr_new) { - int i, j; + int i, j, n; mutex_lock(&sched_domains_mutex); /* always unregister in case we don't destroy any domains */ unregister_sched_domain_sysctl(); - if (doms_new == NULL) - ndoms_new = 0; + n = doms_new ? ndoms_new : 0; /* Destroy deleted domains */ for (i = 0; i < ndoms_cur; i++) { - for (j = 0; j < ndoms_new; j++) { + for (j = 0; j < n; j++) { if (cpus_equal(doms_cur[i], doms_new[j]) && dattrs_equal(dattr_cur, i, dattr_new, j)) goto match1; @@ -7667,7 +7729,6 @@ match1: if (doms_new == NULL) { ndoms_cur = 0; - ndoms_new = 1; doms_new = &fallback_doms; cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map); dattr_new = NULL; @@ -7704,8 +7765,13 @@ match2: int arch_reinit_sched_domains(void) { get_online_cpus(); + + /* Destroy domains first to force the rebuild */ + partition_sched_domains(0, NULL, NULL); + rebuild_sched_domains(); put_online_cpus(); + return 0; } @@ -7789,7 +7855,7 @@ static int update_sched_domains(struct notifier_block *nfb, case CPU_ONLINE_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: - partition_sched_domains(0, NULL, NULL); + partition_sched_domains(1, NULL, NULL); return NOTIFY_OK; default: @@ -8843,6 +8909,9 @@ static int sched_rt_global_constraints(void) u64 rt_runtime, rt_period; int ret = 0; + if (sysctl_sched_rt_period <= 0) + return -EINVAL; + rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period); rt_runtime = tg->rt_bandwidth.rt_runtime; @@ -8859,6 +8928,9 @@ static int sched_rt_global_constraints(void) unsigned long flags; int i; + if (sysctl_sched_rt_period <= 0) + return -EINVAL; + spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags); for_each_possible_cpu(i) { struct rt_rq *rt_rq = &cpu_rq(i)->rt; diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c index 204991a0bfa..e8ab096ddfe 100644 --- a/kernel/sched_clock.c +++ b/kernel/sched_clock.c @@ -12,19 +12,17 @@ * * Create a semi stable clock from a mixture of other events, including: * - gtod - * - jiffies * - sched_clock() * - explicit idle events * * We use gtod as base and the unstable clock deltas. The deltas are filtered, - * making it monotonic and keeping it within an expected window. This window - * is set up using jiffies. + * making it monotonic and keeping it within an expected window. * * Furthermore, explicit sleep and wakeup hooks allow us to account for time * that is otherwise invisible (TSC gets stopped). * * The clock: sched_clock_cpu() is monotonic per cpu, and should be somewhat - * consistent between cpus (never more than 1 jiffies difference). + * consistent between cpus (never more than 2 jiffies difference). */ #include <linux/sched.h> #include <linux/percpu.h> @@ -54,7 +52,6 @@ struct sched_clock_data { */ raw_spinlock_t lock; - unsigned long tick_jiffies; u64 tick_raw; u64 tick_gtod; u64 clock; @@ -75,14 +72,12 @@ static inline struct sched_clock_data *cpu_sdc(int cpu) void sched_clock_init(void) { u64 ktime_now = ktime_to_ns(ktime_get()); - unsigned long now_jiffies = jiffies; int cpu; for_each_possible_cpu(cpu) { struct sched_clock_data *scd = cpu_sdc(cpu); scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; - scd->tick_jiffies = now_jiffies; scd->tick_raw = 0; scd->tick_gtod = ktime_now; scd->clock = ktime_now; @@ -92,46 +87,51 @@ void sched_clock_init(void) } /* + * min,max except they take wrapping into account + */ + +static inline u64 wrap_min(u64 x, u64 y) +{ + return (s64)(x - y) < 0 ? x : y; +} + +static inline u64 wrap_max(u64 x, u64 y) +{ + return (s64)(x - y) > 0 ? x : y; +} + +/* * update the percpu scd from the raw @now value * * - filter out backward motion - * - use jiffies to generate a min,max window to clip the raw values + * - use the GTOD tick value to create a window to filter crazy TSC values */ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now) { - unsigned long now_jiffies = jiffies; - long delta_jiffies = now_jiffies - scd->tick_jiffies; - u64 clock = scd->clock; - u64 min_clock, max_clock; s64 delta = now - scd->tick_raw; + u64 clock, min_clock, max_clock; WARN_ON_ONCE(!irqs_disabled()); - min_clock = scd->tick_gtod + delta_jiffies * TICK_NSEC; - if (unlikely(delta < 0)) { - clock++; - goto out; - } + if (unlikely(delta < 0)) + delta = 0; - max_clock = min_clock + TICK_NSEC; + /* + * scd->clock = clamp(scd->tick_gtod + delta, + * max(scd->tick_gtod, scd->clock), + * scd->tick_gtod + TICK_NSEC); + */ - if (unlikely(clock + delta > max_clock)) { - if (clock < max_clock) - clock = max_clock; - else - clock++; - } else { - clock += delta; - } + clock = scd->tick_gtod + delta; + min_clock = wrap_max(scd->tick_gtod, scd->clock); + max_clock = scd->tick_gtod + TICK_NSEC; - out: - if (unlikely(clock < min_clock)) - clock = min_clock; + clock = wrap_max(clock, min_clock); + clock = wrap_min(clock, max_clock); - scd->tick_jiffies = now_jiffies; scd->clock = clock; - return clock; + return scd->clock; } static void lock_double_clock(struct sched_clock_data *data1, @@ -171,7 +171,7 @@ u64 sched_clock_cpu(int cpu) * larger time as the latest time for both * runqueues. (this creates monotonic movement) */ - if (likely(remote_clock < this_clock)) { + if (likely((s64)(remote_clock - this_clock) < 0)) { clock = this_clock; scd->clock = clock; } else { @@ -207,14 +207,9 @@ void sched_clock_tick(void) now = sched_clock(); __raw_spin_lock(&scd->lock); - __update_sched_clock(scd, now); - /* - * update tick_gtod after __update_sched_clock() because that will - * already observe 1 new jiffy; adding a new tick_gtod to that would - * increase the clock 2 jiffies. - */ scd->tick_raw = now; scd->tick_gtod = now_gtod; + __update_sched_clock(scd, now); __raw_spin_unlock(&scd->lock); } @@ -232,18 +227,7 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event); */ void sched_clock_idle_wakeup_event(u64 delta_ns) { - struct sched_clock_data *scd = this_scd(); - - /* - * Override the previous timestamp and ignore all - * sched_clock() deltas that occured while we idled, - * and use the PM-provided delta_ns to advance the - * rq clock: - */ - __raw_spin_lock(&scd->lock); - scd->clock += delta_ns; - __raw_spin_unlock(&scd->lock); - + sched_clock_tick(); touch_softlockup_watchdog(); } EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); diff --git a/kernel/sched_features.h b/kernel/sched_features.h index 862b06bd560..9353ca78154 100644 --- a/kernel/sched_features.h +++ b/kernel/sched_features.h @@ -8,6 +8,6 @@ SCHED_FEAT(SYNC_WAKEUPS, 1) SCHED_FEAT(HRTICK, 1) SCHED_FEAT(DOUBLE_TICK, 0) SCHED_FEAT(ASYM_GRAN, 1) -SCHED_FEAT(LB_BIAS, 0) +SCHED_FEAT(LB_BIAS, 1) SCHED_FEAT(LB_WAKEUP_UPDATE, 1) SCHED_FEAT(ASYM_EFF_LOAD, 1) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 998ba54b454..1113157b205 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -199,6 +199,8 @@ static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se) static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq) { + if (rt_rq->rt_nr_running) + resched_task(rq_of_rt_rq(rt_rq)->curr); } static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq) @@ -348,6 +350,7 @@ static void __enable_runtime(struct rq *rq) spin_lock(&rt_rq->rt_runtime_lock); rt_rq->rt_runtime = rt_b->rt_runtime; rt_rq->rt_time = 0; + rt_rq->rt_throttled = 0; spin_unlock(&rt_rq->rt_runtime_lock); spin_unlock(&rt_b->rt_runtime_lock); } @@ -438,9 +441,6 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq) { u64 runtime = sched_rt_runtime(rt_rq); - if (runtime == RUNTIME_INF) - return 0; - if (rt_rq->rt_throttled) return rt_rq_throttled(rt_rq); @@ -491,9 +491,11 @@ static void update_curr_rt(struct rq *rq) rt_rq = rt_rq_of_se(rt_se); spin_lock(&rt_rq->rt_runtime_lock); - rt_rq->rt_time += delta_exec; - if (sched_rt_runtime_exceeded(rt_rq)) - resched_task(curr); + if (sched_rt_runtime(rt_rq) != RUNTIME_INF) { + rt_rq->rt_time += delta_exec; + if (sched_rt_runtime_exceeded(rt_rq)) + resched_task(curr); + } spin_unlock(&rt_rq->rt_runtime_lock); } } diff --git a/kernel/smp.c b/kernel/smp.c index 782e2b93e46..f362a855377 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -210,8 +210,10 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, { struct call_single_data d; unsigned long flags; - /* prevent preemption and reschedule on another processor */ + /* prevent preemption and reschedule on another processor, + as well as CPU removal */ int me = get_cpu(); + int err = 0; /* Can deadlock when called with interrupts disabled */ WARN_ON(irqs_disabled()); @@ -220,7 +222,7 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, local_irq_save(flags); func(info); local_irq_restore(flags); - } else { + } else if ((unsigned)cpu < NR_CPUS && cpu_online(cpu)) { struct call_single_data *data = NULL; if (!wait) { @@ -236,10 +238,12 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, data->func = func; data->info = info; generic_exec_single(cpu, data); + } else { + err = -ENXIO; /* CPU not online */ } put_cpu(); - return 0; + return err; } EXPORT_SYMBOL(smp_call_function_single); diff --git a/kernel/softlockup.c b/kernel/softlockup.c index b75b492fbfc..cb838ee93a8 100644 --- a/kernel/softlockup.c +++ b/kernel/softlockup.c @@ -233,7 +233,8 @@ static void check_hung_uninterruptible_tasks(int this_cpu) do_each_thread(g, t) { if (!--max_count) goto unlock; - if (t->state & TASK_UNINTERRUPTIBLE) + /* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */ + if (t->state == TASK_UNINTERRUPTIBLE) check_hung_task(t, now); } while_each_thread(g, t); unlock: diff --git a/kernel/sysctl.c b/kernel/sysctl.c index fe471334727..50ec0886fa3 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -159,6 +159,7 @@ static int proc_dointvec_taint(struct ctl_table *table, int write, struct file * static struct ctl_table root_table[]; static struct ctl_table_root sysctl_table_root; static struct ctl_table_header root_table_header = { + .count = 1, .ctl_table = root_table, .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list), .root = &sysctl_table_root, diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 3d1e3e1a197..f8d968063ce 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -72,6 +72,16 @@ void clockevents_set_mode(struct clock_event_device *dev, } /** + * clockevents_shutdown - shutdown the device and clear next_event + * @dev: device to shutdown + */ +void clockevents_shutdown(struct clock_event_device *dev) +{ + clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN); + dev->next_event.tv64 = KTIME_MAX; +} + +/** * clockevents_program_event - Reprogram the clock event device. * @expires: absolute expiry time (monotonic clock) * @@ -177,7 +187,7 @@ void clockevents_register_device(struct clock_event_device *dev) /* * Noop handler when we shut down an event device */ -static void clockevents_handle_noop(struct clock_event_device *dev) +void clockevents_handle_noop(struct clock_event_device *dev) { } @@ -199,7 +209,6 @@ void clockevents_exchange_device(struct clock_event_device *old, * released list and do a notify add later. */ if (old) { - old->event_handler = clockevents_handle_noop; clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED); list_del(&old->list); list_add(&old->list, &clockevents_released); @@ -207,7 +216,7 @@ void clockevents_exchange_device(struct clock_event_device *old, if (new) { BUG_ON(new->mode != CLOCK_EVT_MODE_UNUSED); - clockevents_set_mode(new, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(new); } local_irq_restore(flags); } diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 5125ddd8196..1ad46f3df6e 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -245,7 +245,7 @@ static void sync_cmos_clock(unsigned long dummy) if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) fail = update_persistent_clock(now); - next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec; + next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2); if (next.tv_nsec <= 0) next.tv_nsec += NSEC_PER_SEC; diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 31463d370b9..cb01cd8f919 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -175,6 +175,8 @@ static void tick_do_periodic_broadcast(void) */ static void tick_handle_periodic_broadcast(struct clock_event_device *dev) { + ktime_t next; + tick_do_periodic_broadcast(); /* @@ -185,10 +187,13 @@ static void tick_handle_periodic_broadcast(struct clock_event_device *dev) /* * Setup the next period for devices, which do not have - * periodic mode: + * periodic mode. We read dev->next_event first and add to it + * when the event alrady expired. clockevents_program_event() + * sets dev->next_event only when the event is really + * programmed to the device. */ - for (;;) { - ktime_t next = ktime_add(dev->next_event, tick_period); + for (next = dev->next_event; ;) { + next = ktime_add(next, tick_period); if (!clockevents_program_event(dev, next, ktime_get())) return; @@ -205,7 +210,7 @@ static void tick_do_broadcast_on_off(void *why) struct clock_event_device *bc, *dev; struct tick_device *td; unsigned long flags, *reason = why; - int cpu; + int cpu, bc_stopped; spin_lock_irqsave(&tick_broadcast_lock, flags); @@ -223,14 +228,16 @@ static void tick_do_broadcast_on_off(void *why) if (!tick_device_is_functional(dev)) goto out; + bc_stopped = cpus_empty(tick_broadcast_mask); + switch (*reason) { case CLOCK_EVT_NOTIFY_BROADCAST_ON: case CLOCK_EVT_NOTIFY_BROADCAST_FORCE: if (!cpu_isset(cpu, tick_broadcast_mask)) { cpu_set(cpu, tick_broadcast_mask); - if (td->mode == TICKDEV_MODE_PERIODIC) - clockevents_set_mode(dev, - CLOCK_EVT_MODE_SHUTDOWN); + if (tick_broadcast_device.mode == + TICKDEV_MODE_PERIODIC) + clockevents_shutdown(dev); } if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE) tick_broadcast_force = 1; @@ -239,15 +246,17 @@ static void tick_do_broadcast_on_off(void *why) if (!tick_broadcast_force && cpu_isset(cpu, tick_broadcast_mask)) { cpu_clear(cpu, tick_broadcast_mask); - if (td->mode == TICKDEV_MODE_PERIODIC) + if (tick_broadcast_device.mode == + TICKDEV_MODE_PERIODIC) tick_setup_periodic(dev, 0); } break; } - if (cpus_empty(tick_broadcast_mask)) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); - else { + if (cpus_empty(tick_broadcast_mask)) { + if (!bc_stopped) + clockevents_shutdown(bc); + } else if (bc_stopped) { if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) tick_broadcast_start_periodic(bc); else @@ -298,7 +307,7 @@ void tick_shutdown_broadcast(unsigned int *cpup) if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) { if (bc && cpus_empty(tick_broadcast_mask)) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(bc); } spin_unlock_irqrestore(&tick_broadcast_lock, flags); @@ -313,7 +322,7 @@ void tick_suspend_broadcast(void) bc = tick_broadcast_device.evtdev; if (bc) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(bc); spin_unlock_irqrestore(&tick_broadcast_lock, flags); } @@ -364,16 +373,8 @@ cpumask_t *tick_get_broadcast_oneshot_mask(void) static int tick_broadcast_set_event(ktime_t expires, int force) { struct clock_event_device *bc = tick_broadcast_device.evtdev; - ktime_t now = ktime_get(); - int res; - - for(;;) { - res = clockevents_program_event(bc, expires, now); - if (!res || !force) - return res; - now = ktime_get(); - expires = ktime_add(now, ktime_set(0, bc->min_delta_ns)); - } + + return tick_dev_program_event(bc, expires, force); } int tick_resume_broadcast_oneshot(struct clock_event_device *bc) @@ -491,14 +492,52 @@ static void tick_broadcast_clear_oneshot(int cpu) cpu_clear(cpu, tick_broadcast_oneshot_mask); } +static void tick_broadcast_init_next_event(cpumask_t *mask, ktime_t expires) +{ + struct tick_device *td; + int cpu; + + for_each_cpu_mask_nr(cpu, *mask) { + td = &per_cpu(tick_cpu_device, cpu); + if (td->evtdev) + td->evtdev->next_event = expires; + } +} + /** * tick_broadcast_setup_oneshot - setup the broadcast device */ void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { - bc->event_handler = tick_handle_oneshot_broadcast; - clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); - bc->next_event.tv64 = KTIME_MAX; + /* Set it up only once ! */ + if (bc->event_handler != tick_handle_oneshot_broadcast) { + int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC; + int cpu = smp_processor_id(); + cpumask_t mask; + + bc->event_handler = tick_handle_oneshot_broadcast; + clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); + + /* Take the do_timer update */ + tick_do_timer_cpu = cpu; + + /* + * We must be careful here. There might be other CPUs + * waiting for periodic broadcast. We need to set the + * oneshot_mask bits for those and program the + * broadcast device to fire. + */ + mask = tick_broadcast_mask; + cpu_clear(cpu, mask); + cpus_or(tick_broadcast_oneshot_mask, + tick_broadcast_oneshot_mask, mask); + + if (was_periodic && !cpus_empty(mask)) { + tick_broadcast_init_next_event(&mask, tick_next_period); + tick_broadcast_set_event(tick_next_period, 1); + } else + bc->next_event.tv64 = KTIME_MAX; + } } /* @@ -538,4 +577,12 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup) spin_unlock_irqrestore(&tick_broadcast_lock, flags); } +/* + * Check, whether the broadcast device is in one shot mode + */ +int tick_broadcast_oneshot_active(void) +{ + return tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT; +} + #endif diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 80c4336f418..df12434b43c 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -33,7 +33,7 @@ DEFINE_PER_CPU(struct tick_device, tick_cpu_device); */ ktime_t tick_next_period; ktime_t tick_period; -int tick_do_timer_cpu __read_mostly = -1; +int tick_do_timer_cpu __read_mostly = TICK_DO_TIMER_BOOT; DEFINE_SPINLOCK(tick_device_lock); /* @@ -109,7 +109,8 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast) if (!tick_device_is_functional(dev)) return; - if (dev->features & CLOCK_EVT_FEAT_PERIODIC) { + if ((dev->features & CLOCK_EVT_FEAT_PERIODIC) && + !tick_broadcast_oneshot_active()) { clockevents_set_mode(dev, CLOCK_EVT_MODE_PERIODIC); } else { unsigned long seq; @@ -148,7 +149,7 @@ static void tick_setup_device(struct tick_device *td, * If no cpu took the do_timer update, assign it to * this cpu: */ - if (tick_do_timer_cpu == -1) { + if (tick_do_timer_cpu == TICK_DO_TIMER_BOOT) { tick_do_timer_cpu = cpu; tick_next_period = ktime_get(); tick_period = ktime_set(0, NSEC_PER_SEC / HZ); @@ -161,6 +162,7 @@ static void tick_setup_device(struct tick_device *td, } else { handler = td->evtdev->event_handler; next_event = td->evtdev->next_event; + td->evtdev->event_handler = clockevents_handle_noop; } td->evtdev = newdev; @@ -248,7 +250,7 @@ static int tick_check_new_device(struct clock_event_device *newdev) * not give it back to the clockevents layer ! */ if (tick_is_broadcast_device(curdev)) { - clockevents_set_mode(curdev, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(curdev); curdev = NULL; } clockevents_exchange_device(curdev, newdev); @@ -299,7 +301,8 @@ static void tick_shutdown(unsigned int *cpup) if (*cpup == tick_do_timer_cpu) { int cpu = first_cpu(cpu_online_map); - tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu : -1; + tick_do_timer_cpu = (cpu != NR_CPUS) ? cpu : + TICK_DO_TIMER_NONE; } spin_unlock_irqrestore(&tick_device_lock, flags); } @@ -310,7 +313,7 @@ static void tick_suspend(void) unsigned long flags; spin_lock_irqsave(&tick_device_lock, flags); - clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN); + clockevents_shutdown(td->evtdev); spin_unlock_irqrestore(&tick_device_lock, flags); } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index f13f2b7f4fd..469248782c2 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -1,6 +1,10 @@ /* * tick internal variable and functions used by low/high res code */ + +#define TICK_DO_TIMER_NONE -1 +#define TICK_DO_TIMER_BOOT -2 + DECLARE_PER_CPU(struct tick_device, tick_cpu_device); extern spinlock_t tick_device_lock; extern ktime_t tick_next_period; @@ -10,6 +14,8 @@ extern int tick_do_timer_cpu __read_mostly; extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast); extern void tick_handle_periodic(struct clock_event_device *dev); +extern void clockevents_shutdown(struct clock_event_device *dev); + /* * NO_HZ / high resolution timer shared code */ @@ -17,6 +23,8 @@ extern void tick_handle_periodic(struct clock_event_device *dev); extern void tick_setup_oneshot(struct clock_event_device *newdev, void (*handler)(struct clock_event_device *), ktime_t nextevt); +extern int tick_dev_program_event(struct clock_event_device *dev, + ktime_t expires, int force); extern int tick_program_event(ktime_t expires, int force); extern void tick_oneshot_notify(void); extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)); @@ -27,6 +35,7 @@ extern void tick_broadcast_oneshot_control(unsigned long reason); extern void tick_broadcast_switch_to_oneshot(void); extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup); extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc); +extern int tick_broadcast_oneshot_active(void); # else /* BROADCAST */ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { @@ -35,6 +44,7 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) static inline void tick_broadcast_oneshot_control(unsigned long reason) { } static inline void tick_broadcast_switch_to_oneshot(void) { } static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { } +static inline int tick_broadcast_oneshot_active(void) { return 0; } # endif /* !BROADCAST */ #else /* !ONESHOT */ @@ -64,6 +74,7 @@ static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc) { return 0; } +static inline int tick_broadcast_oneshot_active(void) { return 0; } #endif /* !TICK_ONESHOT */ /* diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index 450c04935b6..2e8de678e76 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -23,24 +23,56 @@ #include "tick-internal.h" /** - * tick_program_event + * tick_program_event internal worker function */ -int tick_program_event(ktime_t expires, int force) +int tick_dev_program_event(struct clock_event_device *dev, ktime_t expires, + int force) { - struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; ktime_t now = ktime_get(); + int i; - while (1) { + for (i = 0;;) { int ret = clockevents_program_event(dev, expires, now); if (!ret || !force) return ret; + + /* + * We tried 2 times to program the device with the given + * min_delta_ns. If that's not working then we double it + * and emit a warning. + */ + if (++i > 2) { + /* Increase the min. delta and try again */ + if (!dev->min_delta_ns) + dev->min_delta_ns = 5000; + else + dev->min_delta_ns += dev->min_delta_ns >> 1; + + printk(KERN_WARNING + "CE: %s increasing min_delta_ns to %lu nsec\n", + dev->name ? dev->name : "?", + dev->min_delta_ns << 1); + + i = 0; + } + now = ktime_get(); - expires = ktime_add(now, ktime_set(0, dev->min_delta_ns)); + expires = ktime_add_ns(now, dev->min_delta_ns); } } /** + * tick_program_event + */ +int tick_program_event(ktime_t expires, int force) +{ + struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; + + return tick_dev_program_event(dev, expires, force); +} + +/** * tick_resume_onshot - resume oneshot mode */ void tick_resume_oneshot(void) @@ -61,7 +93,7 @@ void tick_setup_oneshot(struct clock_event_device *newdev, { newdev->event_handler = handler; clockevents_set_mode(newdev, CLOCK_EVT_MODE_ONESHOT); - clockevents_program_event(newdev, next_event, ktime_get()); + tick_dev_program_event(newdev, next_event, 1); } /** diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index f5da526424a..cb02324bdb8 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -75,6 +75,9 @@ static void tick_do_update_jiffies64(ktime_t now) incr * ticks); } do_timer(++ticks); + + /* Keep the tick_next_period variable up to date */ + tick_next_period = ktime_add(last_jiffies_update, tick_period); } write_sequnlock(&xtime_lock); } @@ -162,6 +165,8 @@ void tick_nohz_stop_idle(int cpu) ts->idle_lastupdate = now; ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); ts->idle_active = 0; + + sched_clock_idle_wakeup_event(0); } } @@ -177,6 +182,7 @@ static ktime_t tick_nohz_start_idle(struct tick_sched *ts) } ts->idle_entrytime = now; ts->idle_active = 1; + sched_clock_idle_sleep_event(); return now; } @@ -218,7 +224,7 @@ void tick_nohz_stop_sched_tick(int inidle) */ if (unlikely(!cpu_online(cpu))) { if (cpu == tick_do_timer_cpu) - tick_do_timer_cpu = -1; + tick_do_timer_cpu = TICK_DO_TIMER_NONE; } if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE)) @@ -300,7 +306,7 @@ void tick_nohz_stop_sched_tick(int inidle) * invoked. */ if (cpu == tick_do_timer_cpu) - tick_do_timer_cpu = -1; + tick_do_timer_cpu = TICK_DO_TIMER_NONE; ts->idle_sleeps++; @@ -465,7 +471,7 @@ static void tick_nohz_handler(struct clock_event_device *dev) * this duty, then the jiffies update is still serialized by * xtime_lock. */ - if (unlikely(tick_do_timer_cpu == -1)) + if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) tick_do_timer_cpu = cpu; /* Check, if the jiffies need an update */ @@ -567,7 +573,7 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) * this duty, then the jiffies update is still serialized by * xtime_lock. */ - if (unlikely(tick_do_timer_cpu == -1)) + if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) tick_do_timer_cpu = cpu; #endif @@ -619,7 +625,7 @@ void tick_setup_sched_timer(void) */ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); ts->sched_timer.function = tick_sched_timer; - ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + ts->sched_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU; /* Get the next period (per cpu) */ ts->sched_timer.expires = tick_init_jiffy_update(); @@ -643,17 +649,21 @@ void tick_setup_sched_timer(void) ts->nohz_mode = NOHZ_MODE_HIGHRES; #endif } +#endif /* HIGH_RES_TIMERS */ +#if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS void tick_cancel_sched_timer(int cpu) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); +# ifdef CONFIG_HIGH_RES_TIMERS if (ts->sched_timer.base) hrtimer_cancel(&ts->sched_timer); +# endif ts->nohz_mode = NOHZ_MODE_INACTIVE; } -#endif /* HIGH_RES_TIMERS */ +#endif /** * Async notification about clocksource changes diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c index bb948e52ce2..db58fb66a13 100644 --- a/kernel/trace/trace_sysprof.c +++ b/kernel/trace/trace_sysprof.c @@ -202,7 +202,7 @@ static void start_stack_timer(int cpu) hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); hrtimer->function = stack_trace_timer_fn; - hrtimer->cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; + hrtimer->cb_mode = HRTIMER_CB_IRQSAFE_PERCPU; hrtimer_start(hrtimer, ns_to_ktime(sample_period), HRTIMER_MODE_REL); } diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index a9ab0596de4..532858fa5b8 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -6,7 +6,6 @@ */ #include <linux/module.h> -#include <linux/version.h> #include <linux/nsproxy.h> #include <linux/slab.h> #include <linux/user_namespace.h> diff --git a/kernel/utsname.c b/kernel/utsname.c index 64d398f1244..815237a55af 100644 --- a/kernel/utsname.c +++ b/kernel/utsname.c @@ -12,7 +12,6 @@ #include <linux/module.h> #include <linux/uts.h> #include <linux/utsname.h> -#include <linux/version.h> #include <linux/err.h> #include <linux/slab.h> diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c index fe3a56c2256..4ab9659d269 100644 --- a/kernel/utsname_sysctl.c +++ b/kernel/utsname_sysctl.c @@ -12,7 +12,6 @@ #include <linux/module.h> #include <linux/uts.h> #include <linux/utsname.h> -#include <linux/version.h> #include <linux/sysctl.h> static void *get_uts(ctl_table *table, int write) |