GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-07-02 20:29:20 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

rcu: Rework synchronize_sched_expedited() counter handling

Browse source 
Now that synchronize_sched_expedited() have a mutex, it can use simpler
work-already-done detection scheme.  This commit simplifies this scheme
by using something similar to the sequence-locking counter scheme.
A counter is incremented before and after each grace period, so that
the counter is odd in the midst of the grace period and even otherwise.
So if the counter has advanced to the second even number that is
greater than or equal to the snapshot, the required grace period has
already happened.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit is contained in:
Paul E. McKenney 2015-06-24 10:46:30 -07:00
parent c190c3b16c
commit d6ada2cf2f
3 changed files with 36 additions and 83 deletions
Download patch file Download diff file Expand all files Collapse all files

12
kernel/rcu/tree_trace.c
View file

@ -185,18 +185,14 @@ static int show_rcuexp(struct seq_file *m, void *v)
{
struct rcu_state *rsp = (struct rcu_state *)m->private;
seq_printf(m, "s=%lu d=%lu w=%lu tf=%lu wd1=%lu wd2=%lu n=%lu sc=%lu dt=%lu dl=%lu dx=%lu\n",
atomic_long_read(&rsp->expedited_start),
atomic_long_read(&rsp->expedited_done),
atomic_long_read(&rsp->expedited_wrap),
seq_printf(m, "t=%lu tf=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu sc=%lu\n",
rsp->expedited_sequence,
atomic_long_read(&rsp->expedited_tryfail),
atomic_long_read(&rsp->expedited_workdone1),
atomic_long_read(&rsp->expedited_workdone2),
rsp->expedited_workdone3,
atomic_long_read(&rsp->expedited_normal),
atomic_long_read(&rsp->expedited_stoppedcpus),
atomic_long_read(&rsp->expedited_done_tries),
atomic_long_read(&rsp->expedited_done_lost),
atomic_long_read(&rsp->expedited_done_exit));
rsp->expedited_sequence / 2);
return 0;
}