[PATCH 8/9] select/restart_block: Convert poll's timeout to u64

Dmitry Safonov
2019-09-09T10:24:00Z

All preparations have been done - now poll() can set u64 timeout in
restart_block. It allows to do the next step - unifying all timeouts in
restart_block and provide ptrace() API to read it.

Signed-off-by: Dmitry Safonov <dima@arista.com>
---
fs/select.c | 27 +++++++--------------------
include/linux/restart_block.h | 4 +---
2 files changed, 8 insertions(+), 23 deletions(-)

diff --git a/fs/select.c b/fs/select.c
index 4af88feaa2fe..ff2b9c4865cd 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -1001,14 +1001,9 @@ 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 = 0;
+ ktime_t timeout = restart_block->poll.timeout;
int ret;

- if (restart_block->poll.has_timeout) {
- timeout = ktime_set(restart_block->poll.tv_sec,
- restart_block->poll.tv_nsec);
- }
-
ret = do_sys_poll(ufds, nfds, timeout);

if (ret == -ERESTARTNOHAND) {
@@ -1021,14 +1016,12 @@ static long do_restart_poll(struct restart_block *restart_block)
SYSCALL_DEFINE3(poll, struct pollfd __user *, ufds, unsigned int, nfds,
int, timeout_msecs)
{
- struct timespec64 end_time;
ktime_t timeout = 0;
int ret;

if (timeout_msecs >= 0) {
- poll_select_set_timeout(&end_time, timeout_msecs / MSEC_PER_SEC,
- NSEC_PER_MSEC * (timeout_msecs % MSEC_PER_SEC));
- timeout = timespec64_to_ktime(end_time);
+ timeout = ktime_add_ms(0, timeout_msecs);
+ timeout = ktime_add_safe(ktime_get(), timeout);
}

ret = do_sys_poll(ufds, nfds, timeout);
@@ -1037,16 +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;
-
- if (timeout_msecs >= 0) {
- restart_block->poll.tv_sec = end_time.tv_sec;
- restart_block->poll.tv_nsec = end_time.tv_nsec;
- restart_block->poll.has_timeout = 1;
- } else
- restart_block->poll.has_timeout = 0;
+ restart_block->fn = do_restart_poll;
+ restart_block->poll.ufds = ufds;
+ restart_block->poll.nfds = nfds;
+ restart_block->poll.timeout = timeout;

ret = -ERESTART_RESTARTBLOCK;
}
diff --git a/include/linux/restart_block.h b/include/linux/restart_block.h
index e66e982105f4..63d647b65395 100644
--- a/include/linux/restart_block.h
+++ b/include/linux/restart_block.h
@@ -49,11 +49,9 @@ struct restart_block {
} nanosleep;
/* For poll */
struct {
+ u64 timeout;
struct pollfd __user *ufds;
int nfds;
- int has_timeout;
- unsigned long tv_sec;
- unsigned long tv_nsec;
} poll;
};
};
--
2.23.0