net: convert lls to use time_in_range()

Time in range will fail safely if we move to a different cpu with an
extremely large clock skew.
Add time_in_range64() and convert lls to use it.

changelog:
v2
- fixed double call to sched_clock in can_poll_ll
- fixed checkpatchisms

Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/fs/select.c b/fs/select.c
index 36540754bad7..f28a58592725 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -403,7 +403,8 @@ int do_select(int n, fd_set_bits *fds, struct timespec *end_time)
         int retval, i, timed_out = 0;
         unsigned long slack = 0;
         unsigned int ll_flag = ll_get_flag();
-        u64 ll_time = ll_end_time();
+        u64 ll_start = ll_start_time(ll_flag);
+        u64 ll_time = ll_run_time();
 
         rcu_read_lock();
         retval = max_select_fd(n, fds);
@@ -498,7 +499,7 @@ int do_select(int n, fd_set_bits *fds, struct timespec *end_time)
                 }
 
                 /* only if on, have sockets with POLL_LL and not out of time */
-                if (ll_flag && can_ll && can_poll_ll(ll_time))
+                if (ll_flag && can_ll && can_poll_ll(ll_start, ll_time))
                         continue;
 
                 /*
@@ -770,7 +771,8 @@ static int do_poll(unsigned int nfds,  struct poll_list *list,
         int timed_out = 0, count = 0;
         unsigned long slack = 0;
         unsigned int ll_flag = ll_get_flag();
-        u64 ll_time = ll_end_time();
+        u64 ll_start = ll_start_time(ll_flag);
+        u64 ll_time = ll_run_time();
 
         /* Optimise the no-wait case */
         if (end_time && !end_time->tv_sec && !end_time->tv_nsec) {
@@ -819,7 +821,7 @@ static int do_poll(unsigned int nfds,  struct poll_list *list,
                         break;
 
                 /* only if on, have sockets with POLL_LL and not out of time */
-                if (ll_flag && can_ll && can_poll_ll(ll_time))
+                if (ll_flag && can_ll && can_poll_ll(ll_start, ll_time))
                         continue;
 
                 /*