summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'kernel')
-rw-r--r--kernel/exit.c5
-rw-r--r--kernel/hrtimer.c17
-rw-r--r--kernel/sched.c10
-rw-r--r--kernel/sched_debug.c41
-rw-r--r--kernel/sched_fair.c17
-rw-r--r--kernel/softirq.c7
-rw-r--r--kernel/time/tick-sched.c4
-rw-r--r--kernel/trace/ftrace.c8
-rw-r--r--kernel/trace/ring_buffer.c101
9 files changed, 174 insertions, 36 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 80137a5d9467..ae2b92be5fae 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -141,6 +141,11 @@ static void __exit_signal(struct task_struct *tsk)
if (sig) {
flush_sigqueue(&sig->shared_pending);
taskstats_tgid_free(sig);
+ /*
+ * Make sure ->signal can't go away under rq->lock,
+ * see account_group_exec_runtime().
+ */
+ task_rq_unlock_wait(tsk);
__cleanup_signal(sig);
}
}
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 2b465dfde426..95d3949f2ae5 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1209,6 +1209,7 @@ static void run_hrtimer_pending(struct hrtimer_cpu_base *cpu_base)
enum hrtimer_restart (*fn)(struct hrtimer *);
struct hrtimer *timer;
int restart;
+ int emulate_hardirq_ctx = 0;
timer = list_entry(cpu_base->cb_pending.next,
struct hrtimer, cb_entry);
@@ -1217,10 +1218,24 @@ static void run_hrtimer_pending(struct hrtimer_cpu_base *cpu_base)
timer_stats_account_hrtimer(timer);
fn = timer->function;
+ /*
+ * A timer might have been added to the cb_pending list
+ * when it was migrated during a cpu-offline operation.
+ * Emulate hardirq context for such timers.
+ */
+ if (timer->cb_mode == HRTIMER_CB_IRQSAFE_PERCPU ||
+ timer->cb_mode == HRTIMER_CB_IRQSAFE_UNLOCKED)
+ emulate_hardirq_ctx = 1;
+
__remove_hrtimer(timer, timer->base, HRTIMER_STATE_CALLBACK, 0);
spin_unlock_irq(&cpu_base->lock);
- restart = fn(timer);
+ if (unlikely(emulate_hardirq_ctx)) {
+ local_irq_disable();
+ restart = fn(timer);
+ local_irq_enable();
+ } else
+ restart = fn(timer);
spin_lock_irq(&cpu_base->lock);
diff --git a/kernel/sched.c b/kernel/sched.c
index 57c933ffbee1..50a21f964679 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -399,7 +399,7 @@ struct cfs_rq {
*/
struct sched_entity *curr, *next, *last;
- unsigned long nr_spread_over;
+ unsigned int nr_spread_over;
#ifdef CONFIG_FAIR_GROUP_SCHED
struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
@@ -969,6 +969,14 @@ static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
}
}
+void task_rq_unlock_wait(struct task_struct *p)
+{
+ struct rq *rq = task_rq(p);
+
+ smp_mb(); /* spin-unlock-wait is not a full memory barrier */
+ spin_unlock_wait(&rq->lock);
+}
+
static void __task_rq_unlock(struct rq *rq)
__releases(rq->lock)
{
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 5ae17762ec32..48ecc51e7701 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -144,7 +144,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
last = __pick_last_entity(cfs_rq);
if (last)
max_vruntime = last->vruntime;
- min_vruntime = rq->cfs.min_vruntime;
+ min_vruntime = cfs_rq->min_vruntime;
rq0_min_vruntime = per_cpu(runqueues, 0).cfs.min_vruntime;
spin_unlock_irqrestore(&rq->lock, flags);
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "MIN_vruntime",
@@ -161,26 +161,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
SPLIT_NS(spread0));
SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
-#ifdef CONFIG_SCHEDSTATS
-#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
-
- P(yld_exp_empty);
- P(yld_act_empty);
- P(yld_both_empty);
- P(yld_count);
- P(sched_switch);
- P(sched_count);
- P(sched_goidle);
-
- P(ttwu_count);
- P(ttwu_local);
-
- P(bkl_count);
-
-#undef P
-#endif
- SEQ_printf(m, " .%-30s: %ld\n", "nr_spread_over",
+ SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over",
cfs_rq->nr_spread_over);
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_SMP
@@ -260,6 +242,25 @@ static void print_cpu(struct seq_file *m, int cpu)
#undef P
#undef PN
+#ifdef CONFIG_SCHEDSTATS
+#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
+
+ P(yld_exp_empty);
+ P(yld_act_empty);
+ P(yld_both_empty);
+ P(yld_count);
+
+ P(sched_switch);
+ P(sched_count);
+ P(sched_goidle);
+
+ P(ttwu_count);
+ P(ttwu_local);
+
+ P(bkl_count);
+
+#undef P
+#endif
print_cfs_stats(m, cpu);
print_rt_stats(m, cpu);
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 51aa3e102acb..98345e45b059 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -716,6 +716,15 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
__enqueue_entity(cfs_rq, se);
}
+static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ if (cfs_rq->last == se)
+ cfs_rq->last = NULL;
+
+ if (cfs_rq->next == se)
+ cfs_rq->next = NULL;
+}
+
static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
{
@@ -738,11 +747,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
#endif
}
- if (cfs_rq->last == se)
- cfs_rq->last = NULL;
-
- if (cfs_rq->next == se)
- cfs_rq->next = NULL;
+ clear_buddies(cfs_rq, se);
if (se != cfs_rq->curr)
__dequeue_entity(cfs_rq, se);
@@ -977,6 +982,8 @@ static void yield_task_fair(struct rq *rq)
if (unlikely(cfs_rq->nr_running == 1))
return;
+ clear_buddies(cfs_rq, se);
+
if (likely(!sysctl_sched_compat_yield) && curr->policy != SCHED_BATCH) {
update_rq_clock(rq);
/*
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 7110daeb9a90..e7c69a720d69 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -269,10 +269,11 @@ void irq_enter(void)
{
int cpu = smp_processor_id();
- if (idle_cpu(cpu) && !in_interrupt())
+ if (idle_cpu(cpu) && !in_interrupt()) {
+ __irq_enter();
tick_check_idle(cpu);
-
- __irq_enter();
+ } else
+ __irq_enter();
}
#ifdef __ARCH_IRQ_EXIT_IRQS_DISABLED
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 5bbb1044f847..342fc9ccab46 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -568,6 +568,9 @@ static void tick_nohz_switch_to_nohz(void)
*/
static void tick_nohz_kick_tick(int cpu)
{
+#if 0
+ /* Switch back to 2.6.27 behaviour */
+
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
ktime_t delta, now;
@@ -584,6 +587,7 @@ static void tick_nohz_kick_tick(int cpu)
return;
tick_nohz_restart(ts, now);
+#endif
}
#else
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4d2e751bfb11..25b803559f17 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -212,7 +212,6 @@ enum {
};
static int ftrace_filtered;
-static int tracing_on;
static LIST_HEAD(ftrace_new_addrs);
@@ -533,13 +532,10 @@ static int __ftrace_modify_code(void *data)
{
int *command = data;
- if (*command & FTRACE_ENABLE_CALLS) {
+ if (*command & FTRACE_ENABLE_CALLS)
ftrace_replace_code(1);
- tracing_on = 1;
- } else if (*command & FTRACE_DISABLE_CALLS) {
+ else if (*command & FTRACE_DISABLE_CALLS)
ftrace_replace_code(0);
- tracing_on = 0;
- }
if (*command & FTRACE_UPDATE_TRACE_FUNC)
ftrace_update_ftrace_func(ftrace_trace_function);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 8c5cacb25a18..c04c433fbc59 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -18,6 +18,35 @@
#include "trace.h"
+/* Global flag to disable all recording to ring buffers */
+static int ring_buffers_off __read_mostly;
+
+/**
+ * tracing_on - enable all tracing buffers
+ *
+ * This function enables all tracing buffers that may have been
+ * disabled with tracing_off.
+ */
+void tracing_on(void)
+{
+ ring_buffers_off = 0;
+}
+
+/**
+ * tracing_off - turn off all tracing buffers
+ *
+ * This function stops all tracing buffers from recording data.
+ * It does not disable any overhead the tracers themselves may
+ * be causing. This function simply causes all recording to
+ * the ring buffers to fail.
+ */
+void tracing_off(void)
+{
+ ring_buffers_off = 1;
+}
+
+#include "trace.h"
+
/* Up this if you want to test the TIME_EXTENTS and normalization */
#define DEBUG_SHIFT 0
@@ -1143,6 +1172,9 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer,
struct ring_buffer_event *event;
int cpu, resched;
+ if (ring_buffers_off)
+ return NULL;
+
if (atomic_read(&buffer->record_disabled))
return NULL;
@@ -1252,6 +1284,9 @@ int ring_buffer_write(struct ring_buffer *buffer,
int ret = -EBUSY;
int cpu, resched;
+ if (ring_buffers_off)
+ return -EBUSY;
+
if (atomic_read(&buffer->record_disabled))
return -EBUSY;
@@ -2121,3 +2156,69 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
return 0;
}
+static ssize_t
+rb_simple_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ int *p = filp->private_data;
+ char buf[64];
+ int r;
+
+ /* !ring_buffers_off == tracing_on */
+ r = sprintf(buf, "%d\n", !*p);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+rb_simple_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ int *p = filp->private_data;
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ /* !ring_buffers_off == tracing_on */
+ *p = !val;
+
+ (*ppos)++;
+
+ return cnt;
+}
+
+static struct file_operations rb_simple_fops = {
+ .open = tracing_open_generic,
+ .read = rb_simple_read,
+ .write = rb_simple_write,
+};
+
+
+static __init int rb_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+
+ entry = debugfs_create_file("tracing_on", 0644, d_tracer,
+ &ring_buffers_off, &rb_simple_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'tracing_on' entry\n");
+
+ return 0;
+}
+
+fs_initcall(rb_init_debugfs);
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-20 08:04:12 +0000