Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1667130

[RFC v2 0/2] swait: add idle to make idle-hacks on kthreads explicit

Show all headers | View raw

While reviewing RCU's interruptible swaits I noticed signals were actually
not expected. Paul explained that the reason signals are not expected is
we use kthreads, which don't get signals, furthermore the code avoided the
uninterruptible swaits as otherwise it would contribute to the system load
average on idle, bumping it from 0 to 2 or 3 (depending on preemption).

Since this can be confusing its best to be explicit about the requirements and
goals. This patch depends on the other killable swaits [0] recently proposed as
well interms of context. Thee patch can however be tested independently if
the hunk is addressed separately.

[0] https://lkml.kernel.org/r/20170614222017.14653-3-mcgrof@kernel.org

Luis R. Rodriguez (2):
  swait: add idle variants which don't contribute to load average
  rcu: use idle versions of swait to make idle-hack clear

 include/linux/swait.h | 25 +++++++++++++++++++++++++
 kernel/rcu/tree.c     |  4 ++--
 2 files changed, 27 insertions(+), 2 deletions(-)

-- 
2.11.0

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[RFC] rcu: use killable versions of swait "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 01:10 +0200
  Re: [RFC] rcu: use killable versions of swait "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-15 01:50 +0200
    Re: [RFC] rcu: use killable versions of swait "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 18:00 +0200
      Re: [RFC] rcu: use killable versions of swait "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-15 18:30 +0200
        Re: [RFC] rcu: use killable versions of swait "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 18:40 +0200
          Re: [RFC] rcu: use killable versions of swait ebiederm@xmission.com (Eric W. Biederman) - 2017-06-15 19:10 +0200
            [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads explicit "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 20:50 +0200
              [RFC v2 1/2] swait: add idle variants which don't contribute to load average "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 20:50 +0200
                Re: [RFC v2 1/2] swait: add idle variants which don't contribute to  load average Boqun Feng <boqun.feng@gmail.com> - 2017-06-16 02:50 +0200
                Re: [RFC v2 1/2] swait: add idle variants which don't contribute to load average ebiederm@xmission.com (Eric W. Biederman) - 2017-06-16 22:40 +0200
                Re: [RFC v2 1/2] swait: add idle variants which don't contribute to  load average "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-19 20:00 +0200
              [RFC v2 2/2] rcu: use idle versions of swait to make idle-hack clear "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-15 20:50 +0200
              Re: [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads  explicit "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-16 00:00 +0200
                Re: [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads  explicit "Luis R. Rodriguez" <mcgrof@kernel.org> - 2017-06-16 01:30 +0200
                Re: [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads  explicit "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-16 01:50 +0200
                Re: [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads explicit ebiederm@xmission.com (Eric W. Biederman) - 2017-06-16 22:50 +0200
                Re: [RFC v2 0/2] swait: add idle to make idle-hacks on kthreads  explicit "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-19 20:00 +0200
          Re: [RFC] rcu: use killable versions of swait "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2017-06-15 19:40 +0200

csiph-web