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author | Andrew Dodd <atd7@cornell.edu> | 2013-02-16 18:41:04 -0500 |
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committer | Andrew Dodd <atd7@cornell.edu> | 2013-02-27 09:19:08 -0500 |
commit | b08797f2afdfc604c3143f8725d058aeef8ddcb2 (patch) | |
tree | c59e963bd6931d4e9f9526034ab402cc551f18ae /kernel/sched.c | |
parent | cbfae70f1dcaf3cc6e93061179dad80caa1597fe (diff) | |
parent | 54ea5b40f067cf098cac639973c6628c6944cfb2 (diff) | |
download | kernel_samsung_smdk4412-b08797f2afdfc604c3143f8725d058aeef8ddcb2.zip kernel_samsung_smdk4412-b08797f2afdfc604c3143f8725d058aeef8ddcb2.tar.gz kernel_samsung_smdk4412-b08797f2afdfc604c3143f8725d058aeef8ddcb2.tar.bz2 |
Merge remote-tracking branch 'kernelorg/linux-3.0.y' into 3_0_64
Conflicts:
arch/arm/Kconfig
arch/arm/include/asm/hwcap.h
arch/arm/kernel/smp.c
arch/arm/plat-samsung/adc.c
drivers/gpu/drm/i915/i915_reg.h
drivers/gpu/drm/i915/intel_drv.h
drivers/mmc/core/sd.c
drivers/net/tun.c
drivers/net/usb/usbnet.c
drivers/regulator/max8997.c
drivers/usb/core/hub.c
drivers/usb/host/xhci.h
drivers/usb/serial/qcserial.c
fs/jbd2/transaction.c
include/linux/migrate.h
kernel/sys.c
kernel/time/timekeeping.c
lib/genalloc.c
mm/memory-failure.c
mm/memory_hotplug.c
mm/mempolicy.c
mm/page_alloc.c
mm/vmalloc.c
mm/vmscan.c
mm/vmstat.c
scripts/Kbuild.include
Change-Id: I91e2d85c07320c7ccfc04cf98a448e89bed6ade6
Diffstat (limited to 'kernel/sched.c')
-rw-r--r-- | kernel/sched.c | 81 |
1 files changed, 57 insertions, 24 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 3544739..e0c9d50 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -608,22 +608,19 @@ static inline int cpu_of(struct rq *rq) /* * Return the group to which this tasks belongs. * - * We use task_subsys_state_check() and extend the RCU verification with - * pi->lock and rq->lock because cpu_cgroup_attach() holds those locks for each - * task it moves into the cgroup. Therefore by holding either of those locks, - * we pin the task to the current cgroup. + * We cannot use task_subsys_state() and friends because the cgroup + * subsystem changes that value before the cgroup_subsys::attach() method + * is called, therefore we cannot pin it and might observe the wrong value. + * + * The same is true for autogroup's p->signal->autogroup->tg, the autogroup + * core changes this before calling sched_move_task(). + * + * Instead we use a 'copy' which is updated from sched_move_task() while + * holding both task_struct::pi_lock and rq::lock. */ static inline struct task_group *task_group(struct task_struct *p) { - struct task_group *tg; - struct cgroup_subsys_state *css; - - css = task_subsys_state_check(p, cpu_cgroup_subsys_id, - lockdep_is_held(&p->pi_lock) || - lockdep_is_held(&task_rq(p)->lock)); - tg = container_of(css, struct task_group, css); - - return autogroup_task_group(p, tg); + return p->sched_task_group; } /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ @@ -2209,7 +2206,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) * a task's CPU. ->pi_lock for waking tasks, rq->lock for runnable tasks. * * sched_move_task() holds both and thus holding either pins the cgroup, - * see set_task_rq(). + * see task_group(). * * Furthermore, all task_rq users should acquire both locks, see * task_rq_lock(). @@ -7231,11 +7228,8 @@ int sched_domain_level_max; static int __init setup_relax_domain_level(char *str) { - unsigned long val; - - val = simple_strtoul(str, NULL, 0); - if (val < sched_domain_level_max) - default_relax_domain_level = val; + if (kstrtoint(str, 0, &default_relax_domain_level)) + pr_warn("Unable to set relax_domain_level\n"); return 1; } @@ -7428,7 +7422,6 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, if (!sd) return child; - set_domain_attribute(sd, attr); cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); if (child) { sd->level = child->level + 1; @@ -7436,6 +7429,7 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, child->parent = sd; } sd->child = child; + set_domain_attribute(sd, attr); return sd; } @@ -7794,34 +7788,66 @@ int __init sched_create_sysfs_power_savings_entries(struct sysdev_class *cls) } #endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */ +static int num_cpus_frozen; /* used to mark begin/end of suspend/resume */ + /* * Update cpusets according to cpu_active mask. If cpusets are * disabled, cpuset_update_active_cpus() becomes a simple wrapper * around partition_sched_domains(). + * + * If we come here as part of a suspend/resume, don't touch cpusets because we + * want to restore it back to its original state upon resume anyway. */ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { - switch (action & ~CPU_TASKS_FROZEN) { + switch (action) { + case CPU_ONLINE_FROZEN: + case CPU_DOWN_FAILED_FROZEN: + + /* + * num_cpus_frozen tracks how many CPUs are involved in suspend + * resume sequence. As long as this is not the last online + * operation in the resume sequence, just build a single sched + * domain, ignoring cpusets. + */ + num_cpus_frozen--; + if (likely(num_cpus_frozen)) { + partition_sched_domains(1, NULL, NULL); + break; + } + + /* + * This is the last CPU online operation. So fall through and + * restore the original sched domains by considering the + * cpuset configurations. + */ + case CPU_ONLINE: case CPU_DOWN_FAILED: cpuset_update_active_cpus(); - return NOTIFY_OK; + break; default: return NOTIFY_DONE; } + return NOTIFY_OK; } static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, void *hcpu) { - switch (action & ~CPU_TASKS_FROZEN) { + switch (action) { case CPU_DOWN_PREPARE: cpuset_update_active_cpus(); - return NOTIFY_OK; + break; + case CPU_DOWN_PREPARE_FROZEN: + num_cpus_frozen++; + partition_sched_domains(1, NULL, NULL); + break; default: return NOTIFY_DONE; } + return NOTIFY_OK; } static int update_runtime(struct notifier_block *nfb, @@ -8573,6 +8599,7 @@ void sched_destroy_group(struct task_group *tg) */ void sched_move_task(struct task_struct *tsk) { + struct task_group *tg; int on_rq, running; unsigned long flags; struct rq *rq; @@ -8587,6 +8614,12 @@ void sched_move_task(struct task_struct *tsk) if (unlikely(running)) tsk->sched_class->put_prev_task(rq, tsk); + tg = container_of(task_subsys_state_check(tsk, cpu_cgroup_subsys_id, + lockdep_is_held(&tsk->sighand->siglock)), + struct task_group, css); + tg = autogroup_task_group(tsk, tg); + tsk->sched_task_group = tg; + #ifdef CONFIG_FAIR_GROUP_SCHED if (tsk->sched_class->task_move_group) tsk->sched_class->task_move_group(tsk, on_rq); |