Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME

Revert commits

92af4dcb4e ("tracing: Unify the "boot" and "mono" tracing clocks")
127bfa5f43 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior")
7250a4047a ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior")
d6c7270e91 ("timekeeping: Remove boot time specific code")
f2d6fdbfd2 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior")
d6ed449afd ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock")
72199320d4 ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock")

As stated in the pull request for the unification of CLOCK_MONOTONIC and
CLOCK_BOOTTIME, it was clear that we might have to revert the change.

As reported by several folks systemd and other applications rely on the
documented behaviour of CLOCK_MONOTONIC on Linux and break with the above
changes. After resume daemons time out and other timeout related issues are
observed. Rafael compiled this list:

* systemd kills daemons on resume, after >WatchdogSec seconds
  of suspending (Genki Sky).  [Verified that that's because systemd uses
  CLOCK_MONOTONIC and expects it to not include the suspend time.]

* systemd-journald misbehaves after resume:
  systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal
corrupted or uncleanly shut down, renaming and replacing.
  (Mike Galbraith).

* NetworkManager reports "networking disabled" and networking is broken
  after resume 50% of the time (Pavel).  [May be because of systemd.]

* MATE desktop dims the display and starts the screensaver right after
  system resume (Pavel).

* Full system hang during resume (me).  [May be due to systemd or NM or both.]

That happens on debian and open suse systems.

It's sad, that these problems were neither catched in -next nor by those
folks who expressed interest in this change.

Reported-by: Rafael J. Wysocki <[email protected]>
Reported-by: Genki Sky <[email protected]>,
Reported-by: Pavel Machek <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Kevin Easton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mark Salyzyn <[email protected]>
Cc: Michael Kerrisk <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Sergey Senozhatsky <[email protected]>
Cc: Steven Rostedt <[email protected]>
This commit is contained in:
Thomas Gleixner 2018-04-25 15:33:38 +02:00
commit a3ed0e4393
15 changed files with 114 additions and 104 deletions

View file

@ -31,6 +31,7 @@
enum evdev_clock_type {
EV_CLK_REAL = 0,
EV_CLK_MONO,
EV_CLK_BOOT,
EV_CLK_MAX
};
@ -197,10 +198,12 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid)
case CLOCK_REALTIME:
clk_type = EV_CLK_REAL;
break;
case CLOCK_BOOTTIME:
case CLOCK_MONOTONIC:
clk_type = EV_CLK_MONO;
break;
case CLOCK_BOOTTIME:
clk_type = EV_CLK_BOOT;
break;
default:
return -EINVAL;
}
@ -311,6 +314,8 @@ static void evdev_events(struct input_handle *handle,
ev_time[EV_CLK_MONO] = ktime_get();
ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]);
ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO],
TK_OFFS_BOOT);
rcu_read_lock();