Latest revision as of 14:53, 29 April 2020

The time namespace support has been merged in the 5.6 kernel. The current implementation allows setting per-namespace offsets to the system monotonic and boot-time clocks.

The time namespace support in CRIU has been merged in the 3.14 release.

LWN article about time namespaces

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@@ Line 1: / Line 1: @@
-Two things (for now) we want to solve with this:
+The time namespace support has been merged in the 5.6 kernel. The current implementation allows setting per-namespace offsets to the system monotonic and boot-time clocks.
-# Shift timer's offsets
-# Make start-time remain "unchanged" after C/R
-# Continuous flow of monotonic time (CLOCK_MONOTONIC).
-What about other kinds of counters like perf events and trace events?
+[https://github.com/checkpoint-restore/criu/pull/1002 The time namespace support] in CRIU has been merged in the [[Download/criu/3.14 | 3.14 release]].
-=TODO=
+[https://lwn.net/Articles/766089/ LWN article about time namespaces]
-==Required in RFC==
-* selftests to test all we've added
-* TIME_NS iffdefery everywhere
-==Maybe later==
-* CLONE_NEWTIME reuses the last free flag from sys_clone() - any way to still keep extensibility for the syscall?
-* arm64/arm32/s390/power64 - add archs vvar support (nit: big/little-endianess for timespec::nsec)
-* REALTIME-related:
-** REALTIME offsets
-** vvar offsets will need synchronization (like gtod_read_begin()/gtod_read_retry())
-** vfs modification/creation time should work
-** starttime in /proc/pid/stat
-** btime in /proc/stat
-** utime()/utimes()/futimesat() (with times == NULL)
-** utimensat()/futimens() - with UTIME_NOW
-** mq_timedsend()/mq_timedreceive()
-** semtimedop()
-** timerfd
-** timer_create()
-** COARSE times
-** clock_nanosleep()
-* Adjtime (too complicated for PoC)
-* Cpu time for thread/pid/pgid (times())
-* /proc/stat ticks? (top uses them e.g.)
-* pid creation time (probably different unrelated API)
-* clock_tai - if we care about isolation from host's time
-=Git=
-* [https://github.com/0x7f454c46/linux/tree/wip/time-ns https://github.com/0x7f454c46/linux/tree/wip/time-ns]
 =Links=
+* [https://lwn.net/Articles/817650/ 04/2020 <nowiki>[PATCH v3 0/6] arm64: add the time namespace support</nowiki>]
+* [https://lore.kernel.org/lkml/158016896588.31887.14143226032971732742.tglx@nanos.tec.linutronix.de/ 01/2020<nowiki> [GIT pull] timers/core for 5.6-rc1</nowiki>]
+* [https://lkml.kernel.org/r/20191112012724.250792-1-dima@arista.com 11/2019 PATCHv8 00/34 kernel: Introduce Time Namespace]
 * [https://lkml.kernel.org/r/20190206001107.16488-1-dima@arista.com 02/2019 PATCH 00/32 kernel: Introduce Time Namespace]
 * [https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2018-November/006210.html 11/2018 <nowiki>[Ksummit-discuss] [TECH-TOPIC] Multiple time domains</nowiki>]

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Latest revision as of 14:53, 29 April 2020

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