[PATCH 9/9] restart_block: Make common timeout

From: Dmitry Safonov
Date: Mon Sep 09 2019 - 06:24:03 EST

In order to provide a unified API to get the leftover of timeout,
the timeout for different users of restart_block can be joined.
All preparations done, so move timeout out of union and convert
the users.

Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
fs/select.c | 10 +++++-----
include/linux/restart_block.h | 4 +---
kernel/futex.c | 14 +++++++-------
kernel/time/alarmtimer.c | 6 +++---
kernel/time/hrtimer.c | 6 +++---
kernel/time/posix-cpu-timers.c | 6 +++---
6 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/fs/select.c b/fs/select.c
index ff2b9c4865cd..9ab6fc6fb7c5 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -1001,7 +1001,7 @@ static long do_restart_poll(struct restart_block *restart_block)
{
struct pollfd __user *ufds = restart_block->poll.ufds;
int nfds = restart_block->poll.nfds;
- ktime_t timeout = restart_block->poll.timeout;
+ ktime_t timeout = restart_block->timeout;
int ret;

ret = do_sys_poll(ufds, nfds, timeout);
@@ -1030,10 +1030,10 @@ SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
struct restart_block *restart_block;

restart_block = &current->restart_block;
- restart_block->fn = do_restart_poll;
- restart_block->poll.ufds = ufds;
- restart_block->poll.nfds = nfds;
- restart_block->poll.timeout = timeout;
+ restart_block->fn = do_restart_poll;
+ restart_block->poll.ufds = ufds;
+ restart_block->poll.nfds = nfds;
+ restart_block->timeout = timeout;

ret = -ERESTART_RESTARTBLOCK;
}
diff --git a/include/linux/restart_block.h b/include/linux/restart_block.h
index 63d647b65395..02f90ab00a2d 100644
--- a/include/linux/restart_block.h
+++ b/include/linux/restart_block.h
@@ -27,6 +27,7 @@ enum timespec_type {
* userspace tricks in the union.
*/
struct restart_block {
+ s64 timeout;
long (*fn)(struct restart_block *);
union {
/* For futex_wait and futex_wait_requeue_pi */
@@ -35,7 +36,6 @@ struct restart_block {
u32 val;
u32 flags;
u32 bitset;
- u64 time;
} futex;
/* For nanosleep */
struct {
@@ -45,11 +45,9 @@ struct restart_block {
struct __kernel_timespec __user *rmtp;
struct old_timespec32 __user *compat_rmtp;
};
- u64 expires;
} nanosleep;
/* For poll */
struct {
- u64 timeout;
struct pollfd __user *ufds;
int nfds;
} poll;
diff --git a/kernel/futex.c b/kernel/futex.c
index 6d50728ef2e7..0738167e4911 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2755,12 +2755,12 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
goto out;

restart = &current->restart_block;
- restart->fn = futex_wait_restart;
- restart->futex.uaddr = uaddr;
- restart->futex.val = val;
- restart->futex.time = *abs_time;
- restart->futex.bitset = bitset;
- restart->futex.flags = flags | FLAGS_HAS_TIMEOUT;
+ restart->fn = futex_wait_restart;
+ restart->futex.uaddr = uaddr;
+ restart->futex.val = val;
+ restart->timeout = *abs_time;
+ restart->futex.bitset = bitset;
+ restart->futex.flags = flags | FLAGS_HAS_TIMEOUT;

ret = -ERESTART_RESTARTBLOCK;

@@ -2779,7 +2779,7 @@ static long futex_wait_restart(struct restart_block *restart)
ktime_t t, *tp = NULL;

if (restart->futex.flags & FLAGS_HAS_TIMEOUT) {
- t = restart->futex.time;
+ t = restart->timeout;
tp = &t;
}
restart->fn = do_no_restart_syscall;
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 57518efc3810..148b187c371e 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -763,7 +763,7 @@ alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type,
static long __sched alarm_timer_nsleep_restart(struct restart_block *restart)
{
enum alarmtimer_type type = restart->nanosleep.clockid;
- ktime_t exp = restart->nanosleep.expires;
+ ktime_t exp = restart->timeout;
struct alarm alarm;

alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup);
@@ -816,9 +816,9 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
if (flags == TIMER_ABSTIME)
return -ERESTARTNOHAND;

- restart->fn = alarm_timer_nsleep_restart;
+ restart->fn = alarm_timer_nsleep_restart;
restart->nanosleep.clockid = type;
- restart->nanosleep.expires = exp;
+ restart->timeout = exp;
return ret;
}

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 4ba2b50d068f..18d4b0cc919c 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1709,7 +1709,7 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)

hrtimer_init_on_stack(&t.timer, restart->nanosleep.clockid,
HRTIMER_MODE_ABS);
- hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
+ hrtimer_set_expires_tv64(&t.timer, restart->timeout);

ret = do_nanosleep(&t, HRTIMER_MODE_ABS);
destroy_hrtimer_on_stack(&t.timer);
@@ -1741,9 +1741,9 @@ long hrtimer_nanosleep(const struct timespec64 *rqtp,
}

restart = &current->restart_block;
- restart->fn = hrtimer_nanosleep_restart;
+ restart->fn = hrtimer_nanosleep_restart;
restart->nanosleep.clockid = t.timer.base->clockid;
- restart->nanosleep.expires = hrtimer_get_expires_tv64(&t.timer);
+ restart->timeout = hrtimer_get_expires_tv64(&t.timer);
out:
destroy_hrtimer_on_stack(&t.timer);
return ret;
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index b4dddf74dd15..691de00107c2 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1332,8 +1332,8 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags,
* Report back to the user the time still remaining.
*/
restart = &current->restart_block;
- restart->fn = posix_cpu_nsleep_restart;
- restart->nanosleep.expires = expires;
+ restart->fn = posix_cpu_nsleep_restart;
+ restart->timeout = expires;
if (restart->nanosleep.type != TT_NONE)
error = nanosleep_copyout(restart, &it.it_value);
}
@@ -1372,7 +1372,7 @@ static long posix_cpu_nsleep_restart(struct restart_block *restart_block)
clockid_t which_clock = restart_block->nanosleep.clockid;
struct timespec64 t;

- t = ns_to_timespec64(restart_block->nanosleep.expires);
+ t = ns_to_timespec64(restart_block->timeout);

return do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t);
}
--
2.23.0