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authorIngo Molnar <mingo@elte.hu>2008-10-03 10:34:36 +0200
committerIngo Molnar <mingo@elte.hu>2008-10-03 10:34:36 +0200
commitb5259d944279d0b7e78a83849a352d8ba0447c4c (patch)
tree42f0e7dc404bc776f9a736c17f52c121da166fc1 /kernel
parent1c50b728c3e734150b8a4a8310ce3e01bc5c70be (diff)
parent94aca1dac6f6d21f4b07e4864baf7768cabcc6e7 (diff)
Merge commit 'v2.6.27-rc8' into core/rcu
Diffstat (limited to 'kernel')
-rw-r--r--kernel/cgroup.c5
-rw-r--r--kernel/cpuset.c37
-rw-r--r--kernel/exit.c12
-rw-r--r--kernel/kexec.c8
-rw-r--r--kernel/kgdb.c10
-rw-r--r--kernel/sched.c8
-rw-r--r--kernel/sched_rt.c1
-rw-r--r--kernel/time/clockevents.c12
-rw-r--r--kernel/time/tick-broadcast.c21
-rw-r--r--kernel/time/tick-common.c14
-rw-r--r--kernel/time/tick-internal.h9
-rw-r--r--kernel/time/tick-sched.c11
12 files changed, 97 insertions, 51 deletions
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 f227bc17269..827cd9adccb 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -843,37 +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);
}
/**
@@ -883,6 +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;
@@ -917,6 +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);
@@ -927,9 +920,9 @@ 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)
async_rebuild_sched_domains();
@@ -1965,7 +1958,7 @@ 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);
}
}
diff --git a/kernel/exit.c b/kernel/exit.c
index 16395644a98..85a83c83185 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -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:
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/sched.c b/kernel/sched.c
index cc1f81b50b8..13dd2db9fb2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -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);
}
@@ -8909,6 +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;
@@ -8925,6 +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_rt.c b/kernel/sched_rt.c
index 552310798da..1113157b205 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -350,6 +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);
}
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 1876b526c77..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)
*
@@ -206,7 +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/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 2f5a38294bf..bd703454239 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -235,9 +235,8 @@ static void tick_do_broadcast_on_off(void *why)
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 (bc->mode == TICKDEV_MODE_PERIODIC)
+ clockevents_shutdown(dev);
}
if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
tick_broadcast_force = 1;
@@ -246,7 +245,7 @@ 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 (bc->mode == TICKDEV_MODE_PERIODIC)
tick_setup_periodic(dev, 0);
}
break;
@@ -254,7 +253,7 @@ static void tick_do_broadcast_on_off(void *why)
if (cpus_empty(tick_broadcast_mask)) {
if (!bc_stopped)
- clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+ clockevents_shutdown(bc);
} else if (bc_stopped) {
if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
tick_broadcast_start_periodic(bc);
@@ -306,7 +305,7 @@ 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);
@@ -321,7 +320,7 @@ 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);
}
@@ -576,4 +575,12 @@ 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 c4777193d56..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);
@@ -249,7 +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);
@@ -300,7 +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);
}
@@ -311,7 +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 0ffc2918ea6..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
*/
@@ -29,6 +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)
{
@@ -37,6 +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 */
@@ -66,6 +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-sched.c b/kernel/time/tick-sched.c
index a87b0468568..39019b3f762 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);
}
@@ -221,7 +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))
@@ -303,7 +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++;
@@ -468,7 +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 */
@@ -570,7 +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