[RFC / PATCH] hrtimer: consolidate hrtimer_init() + hrtimer_init_sleeper() calls

From: Sebastian Andrzej Siewior
Date: Tue Sep 05 2017 - 09:57:27 EST


hrtimer_init_sleeper() calls require a prior initialisation of the
hrtimer object with hrtimer_init(). Lets make the initialisation of the
hrtimer object part of hrtimer_init_sleeper().
This converts all users in one go. Everyone is using the on-stack
version.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
block/blk-mq.c | 3 +--
include/linux/hrtimer.h | 19 ++++++++++++++++---
include/linux/wait.h | 4 ++--
kernel/futex.c | 19 ++++++++-----------
kernel/time/hrtimer.c | 46 ++++++++++++++++++++++++++++++++++++----------
net/core/pktgen.c | 4 ++--
6 files changed, 65 insertions(+), 30 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 4603b115e234..4663a2c3e7a8 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2740,10 +2740,9 @@ static bool blk_mq_poll_hybrid_sleep(struct request_queue *q,
kt = nsecs;

mode = HRTIMER_MODE_REL;
- hrtimer_init_on_stack(&hs.timer, CLOCK_MONOTONIC, mode);
+ hrtimer_init_sleeper_on_stack(&hs, CLOCK_MONOTONIC, mode, current);
hrtimer_set_expires(&hs.timer, kt);

- hrtimer_init_sleeper(&hs, current);
do {
if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags))
break;
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 012c37fdb688..a5e462dafd7d 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -344,10 +344,17 @@ DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
/* Initialize timers: */
extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
enum hrtimer_mode mode);
+extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id,
+ enum hrtimer_mode mode,
+ struct task_struct *task);

#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
enum hrtimer_mode mode);
+extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
+ clockid_t clock_id,
+ enum hrtimer_mode mode,
+ struct task_struct *task);

extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
#else
@@ -357,6 +364,15 @@ static inline void hrtimer_init_on_stack(struct hrtimer *timer,
{
hrtimer_init(timer, which_clock, mode);
}
+
+static inline void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
+ clockid_t clock_id,
+ enum hrtimer_mode mode,
+ struct task_struct *task)
+{
+ hrtimer_init_sleeper(sl, clock_id, mode, task);
+}
+
static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { }
#endif

@@ -458,9 +474,6 @@ extern long hrtimer_nanosleep(const struct timespec64 *rqtp,
const enum hrtimer_mode mode,
const clockid_t clockid);

-extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
- struct task_struct *tsk);
-
extern int schedule_hrtimeout_range(ktime_t *expires, u64 delta,
const enum hrtimer_mode mode);
extern int schedule_hrtimeout_range_clock(ktime_t *expires,
diff --git a/include/linux/wait.h b/include/linux/wait.h
index dc19880c02f5..41a586acc739 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -482,8 +482,8 @@ do { \
int __ret = 0; \
struct hrtimer_sleeper __t; \
\
- hrtimer_init_on_stack(&__t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); \
- hrtimer_init_sleeper(&__t, current); \
+ hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC, HRTIMER_MODE_REL, \
+ current); \
if ((timeout) != KTIME_MAX) \
hrtimer_start_range_ns(&__t.timer, timeout, \
current->timer_slack_ns, \
diff --git a/kernel/futex.c b/kernel/futex.c
index 3d38eaf05492..2d8719819375 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2553,10 +2553,9 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
if (abs_time) {
to = &timeout;

- hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ?
- CLOCK_REALTIME : CLOCK_MONOTONIC,
- HRTIMER_MODE_ABS);
- hrtimer_init_sleeper(to, current);
+ hrtimer_init_sleeper_on_stack(to, (flags & FLAGS_CLOCKRT) ?
+ CLOCK_REALTIME : CLOCK_MONOTONIC,
+ HRTIMER_MODE_ABS, current);
hrtimer_set_expires_range_ns(&to->timer, *abs_time,
current->timer_slack_ns);
}
@@ -2655,9 +2654,8 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,

if (time) {
to = &timeout;
- hrtimer_init_on_stack(&to->timer, CLOCK_REALTIME,
- HRTIMER_MODE_ABS);
- hrtimer_init_sleeper(to, current);
+ hrtimer_init_sleeper_on_stack(to, CLOCK_REALTIME,
+ HRTIMER_MODE_ABS, current);
hrtimer_set_expires(&to->timer, *time);
}

@@ -3053,10 +3051,9 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,

if (abs_time) {
to = &timeout;
- hrtimer_init_on_stack(&to->timer, (flags & FLAGS_CLOCKRT) ?
- CLOCK_REALTIME : CLOCK_MONOTONIC,
- HRTIMER_MODE_ABS);
- hrtimer_init_sleeper(to, current);
+ hrtimer_init_sleeper_on_stack(to, (flags & FLAGS_CLOCKRT) ?
+ CLOCK_REALTIME : CLOCK_MONOTONIC,
+ HRTIMER_MODE_ABS, current);
hrtimer_set_expires_range_ns(&to->timer, *abs_time,
current->timer_slack_ns);
}
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 88f75f92ef36..8295798d89ff 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1433,13 +1433,44 @@ static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer)
return HRTIMER_NORESTART;
}

-void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
+static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
+ clockid_t clock_id,
+ enum hrtimer_mode mode,
+ struct task_struct *task)
{
+ __hrtimer_init(&sl->timer, clock_id, mode);
sl->timer.function = hrtimer_wakeup;
sl->task = task;
}
+
+/**
+ * hrtimer_init_sleeper - initialize sleeper to the given clock
+ * @sl: sleeper to be initialized
+ * @clock_id: the clock to be used
+ * @mode: timer mode abs/rel
+ * @task: the task to wake up
+ */
+void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id,
+ enum hrtimer_mode mode, struct task_struct *task)
+{
+ debug_init(&sl->timer, clock_id, mode);
+ __hrtimer_init_sleeper(sl, clock_id, mode, task);
+
+}
EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);

+#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
+void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
+ clockid_t clock_id,
+ enum hrtimer_mode mode,
+ struct task_struct *task)
+{
+ debug_object_init_on_stack(&sl->timer, &hrtimer_debug_descr);
+ __hrtimer_init_sleeper(sl, clock_id, mode, task);
+}
+EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
+#endif
+
int nanosleep_copyout(struct restart_block *restart, struct timespec64 *ts)
{
switch(restart->nanosleep.type) {
@@ -1463,8 +1494,6 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
{
struct restart_block *restart;

- hrtimer_init_sleeper(t, current);
-
do {
set_current_state(TASK_INTERRUPTIBLE);
hrtimer_start_expires(&t->timer, mode);
@@ -1501,10 +1530,9 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
struct hrtimer_sleeper t;
int ret;

- hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
- HRTIMER_MODE_ABS);
+ hrtimer_init_sleeper_on_stack(&t, restart->nanosleep.clockid,
+ HRTIMER_MODE_ABS, current);
hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
-
ret = do_nanosleep(&t, HRTIMER_MODE_ABS);
destroy_hrtimer_on_stack(&t.timer);
return ret;
@@ -1522,7 +1550,7 @@ long hrtimer_nanosleep(const struct timespec64 *rqtp,
if (dl_task(current) || rt_task(current))
slack = 0;

- hrtimer_init_on_stack(&t.timer, clockid, mode);
+ hrtimer_init_sleeper_on_stack(&t, clockid, mode, current);
hrtimer_set_expires_range_ns(&t.timer, timespec64_to_ktime(*rqtp), slack);
ret = do_nanosleep(&t, mode);
if (ret != -ERESTART_RESTARTBLOCK)
@@ -1697,11 +1725,9 @@ schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta,
return -EINTR;
}

- hrtimer_init_on_stack(&t.timer, clock, mode);
+ hrtimer_init_sleeper_on_stack(&t, clock, mode, current);
hrtimer_set_expires_range_ns(&t.timer, *expires, delta);

- hrtimer_init_sleeper(&t, current);
-
hrtimer_start_expires(&t.timer, mode);

if (likely(t.task))
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 6e1e10ff433a..c1ae4075e0ed 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2252,7 +2252,8 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
s64 remaining;
struct hrtimer_sleeper t;

- hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+ hrtimer_init_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_ABS,
+ current);
hrtimer_set_expires(&t.timer, spin_until);

remaining = ktime_to_ns(hrtimer_expires_remaining(&t.timer));
@@ -2267,7 +2268,6 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
} while (ktime_compare(end_time, spin_until) < 0);
} else {
/* see do_nanosleep */
- hrtimer_init_sleeper(&t, current);
do {
set_current_state(TASK_INTERRUPTIBLE);
hrtimer_start_expires(&t.timer, HRTIMER_MODE_ABS);
--
2.14.1