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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-02-22 01:12:47 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-02-22 01:12:47 -0300
commit6d461a4fe7896faa1aec5a5417888cf179e46b9f (patch)
tree2e0f1a0b7a5418189c8d53592d33a44d0b356fc9 /kernel
parent5c545e1fb127a4b11ddc5f1a5ed066b853dd1a1a (diff)
Linux-libre 4.4.2-gnupck-4.4.2-gnu
Diffstat (limited to 'kernel')
-rw-r--r--kernel/panic.c3
-rw-r--r--kernel/printk/printk.c35
-rw-r--r--kernel/sched/core.c2
-rw-r--r--kernel/task_work.c1
-rw-r--r--kernel/time/hrtimer.c55
-rw-r--r--kernel/time/timer_list.c2
-rw-r--r--kernel/trace/trace.c2
-rw-r--r--kernel/trace/trace_stack.c7
8 files changed, 83 insertions, 24 deletions
diff --git a/kernel/panic.c b/kernel/panic.c
index 4b150bc0c..41e2b54f3 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -157,8 +157,7 @@ void panic(const char *fmt, ...)
* panic() is not being callled from OOPS.
*/
debug_locks_off();
- console_trylock();
- console_unlock();
+ console_flush_on_panic();
if (!panic_blink)
panic_blink = no_blink;
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index f9b746700..8362f1979 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2248,13 +2248,24 @@ void console_unlock(void)
static u64 seen_seq;
unsigned long flags;
bool wake_klogd = false;
- bool retry;
+ bool do_cond_resched, retry;
if (console_suspended) {
up_console_sem();
return;
}
+ /*
+ * Console drivers are called under logbuf_lock, so
+ * @console_may_schedule should be cleared before; however, we may
+ * end up dumping a lot of lines, for example, if called from
+ * console registration path, and should invoke cond_resched()
+ * between lines if allowable. Not doing so can cause a very long
+ * scheduling stall on a slow console leading to RCU stall and
+ * softlockup warnings which exacerbate the issue with more
+ * messages practically incapacitating the system.
+ */
+ do_cond_resched = console_may_schedule;
console_may_schedule = 0;
/* flush buffered message fragment immediately to console */
@@ -2326,6 +2337,9 @@ skip:
call_console_drivers(level, ext_text, ext_len, text, len);
start_critical_timings();
local_irq_restore(flags);
+
+ if (do_cond_resched)
+ cond_resched();
}
console_locked = 0;
@@ -2393,6 +2407,25 @@ void console_unblank(void)
console_unlock();
}
+/**
+ * console_flush_on_panic - flush console content on panic
+ *
+ * Immediately output all pending messages no matter what.
+ */
+void console_flush_on_panic(void)
+{
+ /*
+ * If someone else is holding the console lock, trylock will fail
+ * and may_schedule may be set. Ignore and proceed to unlock so
+ * that messages are flushed out. As this can be called from any
+ * context and we don't want to get preempted while flushing,
+ * ensure may_schedule is cleared.
+ */
+ console_trylock();
+ console_may_schedule = 0;
+ console_unlock();
+}
+
/*
* Return the console tty driver structure and its associated index
*/
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 732e993b5..eb70592f0 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6738,7 +6738,7 @@ static void sched_init_numa(void)
sched_domains_numa_masks[i][j] = mask;
- for (k = 0; k < nr_node_ids; k++) {
+ for_each_node(k) {
if (node_distance(j, k) > sched_domains_numa_distance[i])
continue;
diff --git a/kernel/task_work.c b/kernel/task_work.c
index 53fa971d0..f80d564c7 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -118,3 +118,4 @@ void task_work_run(void)
} while (work);
}
}
+EXPORT_SYMBOL(task_work_run);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 435b8850d..fa909f9fd 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -897,10 +897,10 @@ static int enqueue_hrtimer(struct hrtimer *timer,
*/
static void __remove_hrtimer(struct hrtimer *timer,
struct hrtimer_clock_base *base,
- unsigned long newstate, int reprogram)
+ u8 newstate, int reprogram)
{
struct hrtimer_cpu_base *cpu_base = base->cpu_base;
- unsigned int state = timer->state;
+ u8 state = timer->state;
timer->state = newstate;
if (!(state & HRTIMER_STATE_ENQUEUED))
@@ -930,7 +930,7 @@ static inline int
remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool restart)
{
if (hrtimer_is_queued(timer)) {
- unsigned long state = timer->state;
+ u8 state = timer->state;
int reprogram;
/*
@@ -954,6 +954,22 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool rest
return 0;
}
+static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim,
+ const enum hrtimer_mode mode)
+{
+#ifdef CONFIG_TIME_LOW_RES
+ /*
+ * CONFIG_TIME_LOW_RES indicates that the system has no way to return
+ * granular time values. For relative timers we add hrtimer_resolution
+ * (i.e. one jiffie) to prevent short timeouts.
+ */
+ timer->is_rel = mode & HRTIMER_MODE_REL;
+ if (timer->is_rel)
+ tim = ktime_add_safe(tim, ktime_set(0, hrtimer_resolution));
+#endif
+ return tim;
+}
+
/**
* hrtimer_start_range_ns - (re)start an hrtimer on the current CPU
* @timer: the timer to be added
@@ -974,19 +990,10 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
/* Remove an active timer from the queue: */
remove_hrtimer(timer, base, true);
- if (mode & HRTIMER_MODE_REL) {
+ if (mode & HRTIMER_MODE_REL)
tim = ktime_add_safe(tim, base->get_time());
- /*
- * CONFIG_TIME_LOW_RES is a temporary way for architectures
- * to signal that they simply return xtime in
- * do_gettimeoffset(). In this case we want to round up by
- * resolution when starting a relative timer, to avoid short
- * timeouts. This will go away with the GTOD framework.
- */
-#ifdef CONFIG_TIME_LOW_RES
- tim = ktime_add_safe(tim, ktime_set(0, hrtimer_resolution));
-#endif
- }
+
+ tim = hrtimer_update_lowres(timer, tim, mode);
hrtimer_set_expires_range_ns(timer, tim, delta_ns);
@@ -1074,19 +1081,23 @@ EXPORT_SYMBOL_GPL(hrtimer_cancel);
/**
* hrtimer_get_remaining - get remaining time for the timer
* @timer: the timer to read
+ * @adjust: adjust relative timers when CONFIG_TIME_LOW_RES=y
*/
-ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
+ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust)
{
unsigned long flags;
ktime_t rem;
lock_hrtimer_base(timer, &flags);
- rem = hrtimer_expires_remaining(timer);
+ if (IS_ENABLED(CONFIG_TIME_LOW_RES) && adjust)
+ rem = hrtimer_expires_remaining_adjusted(timer);
+ else
+ rem = hrtimer_expires_remaining(timer);
unlock_hrtimer_base(timer, &flags);
return rem;
}
-EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
+EXPORT_SYMBOL_GPL(__hrtimer_get_remaining);
#ifdef CONFIG_NO_HZ_COMMON
/**
@@ -1220,6 +1231,14 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
fn = timer->function;
/*
+ * Clear the 'is relative' flag for the TIME_LOW_RES case. If the
+ * timer is restarted with a period then it becomes an absolute
+ * timer. If its not restarted it does not matter.
+ */
+ if (IS_ENABLED(CONFIG_TIME_LOW_RES))
+ timer->is_rel = false;
+
+ /*
* Because we run timers from hardirq context, there is no chance
* they get migrated to another cpu, therefore its safe to unlock
* the timer base.
diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index f75e35b60..ba7d8b288 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -69,7 +69,7 @@ print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
print_name_offset(m, taddr);
SEQ_printf(m, ", ");
print_name_offset(m, timer->function);
- SEQ_printf(m, ", S:%02lx", timer->state);
+ SEQ_printf(m, ", S:%02x", timer->state);
#ifdef CONFIG_TIMER_STATS
SEQ_printf(m, ", ");
print_name_offset(m, timer->start_site);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 87fb9801b..d9293402e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1751,7 +1751,7 @@ void trace_buffer_unlock_commit_regs(struct trace_array *tr,
{
__buffer_unlock_commit(buffer, event);
- ftrace_trace_stack(tr, buffer, flags, 6, pc, regs);
+ ftrace_trace_stack(tr, buffer, flags, 0, pc, regs);
ftrace_trace_userstack(buffer, flags, pc);
}
EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs);
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index dda9e6742..202df6cff 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -126,6 +126,13 @@ check_stack(unsigned long ip, unsigned long *stack)
}
/*
+ * Some archs may not have the passed in ip in the dump.
+ * If that happens, we need to show everything.
+ */
+ if (i == stack_trace_max.nr_entries)
+ i = 0;
+
+ /*
* Now find where in the stack these are.
*/
x = 0;