integ/base/systemd/centos/patches/912-sd-event-refuse-running-default-event-loops-in-any-o.patch
Li Zhou ccfeeef59d systemd: Prevent excessive /proc/1/mountinfo reparsing
Backport the patches for this issue:
https://bugzilla.redhat.com/show_bug.cgi?id=1819868

We met such an issue:
When testing a large number of pods (> 230), occasionally observed a
number of issues related to systemd process:
    systemd ran continually 90-100% cpu usage
    systemd memory usage started increasing rapidly (20GB/hour)
    systemctl commands would always timeout (Failed to get properties:
        Connection timed out)
    sm services failed and can't recover: open-ldap,
        registry-token-server, docker-distribution, etcd
    new pods can't start, and got stuck in state ContainerCreating

Those patches work to prevent excessive /proc/1/mountinfo reparsing.
It has been verified that those patches can improve this performance
greatly.

16 commits are listed in sequence (from [1] to [16]) at below link
for the issue:
https://github.com/systemd-rhel/rhel-8/pull/154/commits

[16](10)core: prevent excessive /proc/self/mountinfo parsing
[15][Dropped-6]test: add ratelimiting test
[14](9)sd-event: add ability to ratelimit event sources
[13](8)sd-event: increase n_enabled_child_sources just once
[12](7)sd-event: update state at the end in event_source_enable
[11](6)sd-event: remove earliest_index/latest_index into common part of
event source objects
[10][Dropped-5]sd-event: follow coding style with naming return
parameter
[9] [Dropped-4]sd-event: ref event loop while in sd_event_prepare() ot
sd_event_run()
[8] (5)sd-event: refuse running default event loops in any other thread
than the one they are default for
[7] [Dropped-3]sd-event: let's suffix last_run/last_log with "_usec"
[6] [Dropped-2]sd-event: fix delays assert brain-o (#17790)
[5] (4)sd-event: split out code to add/remove timer event sources to
earliest/latest prioq
[4] (3)sd-event: split clock data allocation out of sd_event_add_time()
[3] [Dropped-1]sd-event: mention that two debug logged events are
ignored
[2] (2)sd-event: split out enable and disable codepaths from
sd_event_source_set_enabled()
[1] (1)sd-event: split out helper functions for reshuffling prioqs

I ported 10 of them back (from (1) to (10)) to fix this issue
and dropped the other 6 (from [Dropped-1] to [Dropped-6]) for those
reasons:
[Dropped-1]Only changes error log.
[Dropped-2]Fixes a bug introduced in a commit which doesn't exist in
this version.
[Dropped-3]Only changes vars' names and there is no functional change.
[Dropped-4]More commits are needed for merging it, while I don't see
any help on adding the rate-limiting ability.
[Dropped-5]Change coding style for a function which isn't really used
by anyone.
[Dropped-6]Add test cases.

Closes-Bug: #1924686
Signed-off-by: Li Zhou <li.zhou@windriver.com>
Change-Id: Ia4c8f162cb1a47b40d1b26cf4d604976b97e92d6
2021-04-22 22:09:33 -04:00

40 lines
1.4 KiB
Diff

From 01c94571660c44c415ba8bcba62176f45bf84be5 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Wed, 30 Oct 2019 20:26:50 +0100
Subject: [PATCH 12/20] sd-event: refuse running default event loops in any
other thread than the one they are default for
(cherry picked from commit e544601536ac13a288d7476f4400c7b0f22b7ea1)
Related: #1819868
[commit 4c5fdbde7e745126f31542a70b45cc4faec094d2 from
https://github.com/systemd-rhel/rhel-8/
LZ: Dropped the part that won't affect code to simplify the merging.]
Signed-off-by: Li Zhou <li.zhou@windriver.com>
---
src/libsystemd/sd-event/sd-event.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
index 299312a..a2f7868 100644
--- a/src/libsystemd/sd-event/sd-event.c
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -2494,6 +2494,11 @@ _public_ int sd_event_prepare(sd_event *e) {
assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
assert_return(e->state == SD_EVENT_INITIAL, -EBUSY);
+ /* Let's check that if we are a default event loop we are executed in the correct thread. We only do
+ * this check here once, since gettid() is typically not cached, and thus want to minimize
+ * syscalls */
+ assert_return(!e->default_event_ptr || e->tid == gettid(), -EREMOTEIO);
+
if (e->exit_requested)
goto pending;
--
2.17.1