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-rw-r--r--kernel/futex.c7
-rw-r--r--kernel/rcutiny.c3
-rw-r--r--kernel/srcu.c15
-rw-r--r--kernel/time/clocksource.c8
-rw-r--r--kernel/time/timekeeping.c4
-rw-r--r--kernel/trace/trace_syscalls.c33
6 files changed, 36 insertions, 34 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index 52075633373f..b766d28accd6 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -826,10 +826,9 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
/*
- * This happens when we have stolen the lock and the original
- * pending owner did not enqueue itself back on the rt_mutex.
- * Thats not a tragedy. We know that way, that a lock waiter
- * is on the fly. We make the futex_q waiter the pending owner.
+ * It is possible that the next waiter (the one that brought
+ * this owner to the kernel) timed out and is no longer
+ * waiting on the lock.
*/
if (!new_owner)
new_owner = this->task;
diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index 034493724749..0c343b9a46d5 100644
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -189,7 +189,8 @@ static int rcu_kthread(void *arg)
unsigned long flags;
for (;;) {
- wait_event(rcu_kthread_wq, have_rcu_kthread_work != 0);
+ wait_event_interruptible(rcu_kthread_wq,
+ have_rcu_kthread_work != 0);
morework = rcu_boost();
local_irq_save(flags);
work = have_rcu_kthread_work;
diff --git a/kernel/srcu.c b/kernel/srcu.c
index 98d8c1e80edb..73ce23feaea9 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -156,6 +156,16 @@ void __srcu_read_unlock(struct srcu_struct *sp, int idx)
EXPORT_SYMBOL_GPL(__srcu_read_unlock);
/*
+ * We use an adaptive strategy for synchronize_srcu() and especially for
+ * synchronize_srcu_expedited(). We spin for a fixed time period
+ * (defined below) to allow SRCU readers to exit their read-side critical
+ * sections. If there are still some readers after 10 microseconds,
+ * we repeatedly block for 1-millisecond time periods. This approach
+ * has done well in testing, so there is no need for a config parameter.
+ */
+#define SYNCHRONIZE_SRCU_READER_DELAY 10
+
+/*
* Helper function for synchronize_srcu() and synchronize_srcu_expedited().
*/
static void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void))
@@ -207,11 +217,12 @@ static void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void))
* will have finished executing. We initially give readers
* an arbitrarily chosen 10 microseconds to get out of their
* SRCU read-side critical sections, then loop waiting 1/HZ
- * seconds per iteration.
+ * seconds per iteration. The 10-microsecond value has done
+ * very well in testing.
*/
if (srcu_readers_active_idx(sp, idx))
- udelay(CONFIG_SRCU_SYNCHRONIZE_DELAY);
+ udelay(SYNCHRONIZE_SRCU_READER_DELAY);
while (srcu_readers_active_idx(sp, idx))
schedule_timeout_interruptible(1);
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index c50a034de30f..6519cf62d9cd 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -113,7 +113,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time);
* @shift: pointer to shift variable
* @from: frequency to convert from
* @to: frequency to convert to
- * @minsec: guaranteed runtime conversion range in seconds
+ * @maxsec: guaranteed runtime conversion range in seconds
*
* The function evaluates the shift/mult pair for the scaled math
* operations of clocksources and clockevents.
@@ -122,7 +122,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time);
* NSEC_PER_SEC == 1GHz and @from is the counter frequency. For clock
* event @to is the counter frequency and @from is NSEC_PER_SEC.
*
- * The @minsec conversion range argument controls the time frame in
+ * The @maxsec conversion range argument controls the time frame in
* seconds which must be covered by the runtime conversion with the
* calculated mult and shift factors. This guarantees that no 64bit
* overflow happens when the input value of the conversion is
@@ -131,7 +131,7 @@ EXPORT_SYMBOL_GPL(timecounter_cyc2time);
* factors.
*/
void
-clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec)
+clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec)
{
u64 tmp;
u32 sft, sftacc= 32;
@@ -140,7 +140,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec)
* Calculate the shift factor which is limiting the conversion
* range:
*/
- tmp = ((u64)minsec * from) >> 32;
+ tmp = ((u64)maxsec * from) >> 32;
while (tmp) {
tmp >>=1;
sftacc--;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 5536aaf3ba36..d27c7562902c 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -49,7 +49,7 @@ struct timekeeper {
u32 mult;
};
-struct timekeeper timekeeper;
+static struct timekeeper timekeeper;
/**
* timekeeper_setup_internals - Set up internals to use clocksource clock.
@@ -164,7 +164,7 @@ static struct timespec total_sleep_time;
/*
* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
*/
-struct timespec raw_time;
+static struct timespec raw_time;
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index bac752f0cfb5..b706529b4fc7 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -23,9 +23,6 @@ static int syscall_exit_register(struct ftrace_event_call *event,
static int syscall_enter_define_fields(struct ftrace_event_call *call);
static int syscall_exit_define_fields(struct ftrace_event_call *call);
-/* All syscall exit events have the same fields */
-static LIST_HEAD(syscall_exit_fields);
-
static struct list_head *
syscall_get_enter_fields(struct ftrace_event_call *call)
{
@@ -34,34 +31,28 @@ syscall_get_enter_fields(struct ftrace_event_call *call)
return &entry->enter_fields;
}
-static struct list_head *
-syscall_get_exit_fields(struct ftrace_event_call *call)
-{
- return &syscall_exit_fields;
-}
-
struct trace_event_functions enter_syscall_print_funcs = {
- .trace = print_syscall_enter,
+ .trace = print_syscall_enter,
};
struct trace_event_functions exit_syscall_print_funcs = {
- .trace = print_syscall_exit,
+ .trace = print_syscall_exit,
};
struct ftrace_event_class event_class_syscall_enter = {
- .system = "syscalls",
- .reg = syscall_enter_register,
- .define_fields = syscall_enter_define_fields,
- .get_fields = syscall_get_enter_fields,
- .raw_init = init_syscall_trace,
+ .system = "syscalls",
+ .reg = syscall_enter_register,
+ .define_fields = syscall_enter_define_fields,
+ .get_fields = syscall_get_enter_fields,
+ .raw_init = init_syscall_trace,
};
struct ftrace_event_class event_class_syscall_exit = {
- .system = "syscalls",
- .reg = syscall_exit_register,
- .define_fields = syscall_exit_define_fields,
- .get_fields = syscall_get_exit_fields,
- .raw_init = init_syscall_trace,
+ .system = "syscalls",
+ .reg = syscall_exit_register,
+ .define_fields = syscall_exit_define_fields,
+ .fields = LIST_HEAD_INIT(event_class_syscall_exit.fields),
+ .raw_init = init_syscall_trace,
};
extern unsigned long __start_syscalls_metadata[];