HAProxy - Load balancer
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Willy Tarreau 341ac99f4d BUG/MEDIUM: task: relax one thread consistency check in task_unlink_wq()
While testing the fix for the previous issue related to reloads with
hard_stop_after, I've met another one which could spuriously produce:

  FATAL: bug condition "t->tid >= 0 && t->tid != tid" matched at include/haproxy/task.h:266

In 2.3-dev2, we've added more consistency checks for a number of bug-
inducing programming errors related to the tasks, via commit e5d79bccc
("MINOR: tasks/debug: add a few BUG_ON() to detect use of wrong timer
queue"), and this check comes from there.

The problem that happens here is that when hard-stop-after is set, we
can abort the current thread even if there are still ongoing checks
(or connections in fact). In this case some tasks are present in a
thread's wait queue and are thus bound exclusively to this thread.

During deinit(), the collect and cleanup of all memory areas also
stops servers and kills their check tasks. And calling task_destroy()
does in turn call task_unlink_wq()... except that it's called from
thread 0 which doesn't match the initially planned thread number.

Several approaches are possible. One of them would consist in letting
threads perform their own cleanup (tasks, pools, FDs, etc). This would
possibly be even faster since done in parallel, but some corner cases
might be way more complicated (e.g. who will kill a check's task, or
what to do with a task found in a local wait queue or run queue, and
what about other consistency checks this could violate?).

Thus for now this patches takes an easier and more conservative
approach consisting in admitting that when the process is stopping,
this rule is not necessarily valid, and to let thread 0 collect all
other threads' garbage.

As such this patch can be backpoted to 2.4.
2022-08-10 18:03:11 +02:00
.github CI: enable weekly "m32" builds on x86_64 2022-08-06 17:10:16 +02:00
addons CLEANUP: assorted typo fixes in the code and comments 2022-08-06 17:12:51 +02:00
admin BUILD: halog: fix some incorrect signs in printf formats for integers 2022-04-12 08:40:38 +02:00
dev CLEANUP: task: remove the now unused TASK_GLOBAL flag 2022-07-01 19:15:14 +02:00
doc [RELEASE] Released version 2.7-dev3 2022-08-07 17:28:59 +02:00
examples EXAMPLES: remove completely outdated acl-content-sw.cfg 2022-05-30 18:14:24 +02:00
include BUG/MEDIUM: task: relax one thread consistency check in task_unlink_wq() 2022-08-10 18:03:11 +02:00
reg-tests REGTESTS: ssl: fix grep invocation to use extended regex in ssl_generate_certificate.vtc 2022-08-06 23:24:13 +02:00
scripts BUILD: SSL: allow to pass additional configure args to QUICTLS 2022-08-06 17:10:04 +02:00
src BUG/MEDIUM: poller: use fd_delete() to release the poller pipes 2022-08-10 17:25:23 +02:00
tests TESTS: add a unit test for one_among_mask() 2022-06-21 20:29:57 +02:00
.cirrus.yml CI: cirrus: switch to FreeBSD-13.0 2022-04-12 07:59:06 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore MINOR: qpack: implement standalone decoder tool 2022-06-15 15:42:10 +02:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml CI: travis-ci: temporarily disable arm64 builds 2021-08-07 07:28:15 +02:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
CHANGELOG [RELEASE] Released version 2.7-dev3 2022-08-07 17:28:59 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL BUILD: Makefile: Add Lua 5.4 autodetect 2022-07-04 17:28:48 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS DOC: add maintainers for QUIC and HTTP/3 2022-05-30 17:34:51 +02:00
Makefile MINOR: thread: provide an alternative to pthread's rwlock 2022-07-30 10:17:22 +02:00
README DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 2.7-dev3 2022-08-07 17:28:59 +02:00
VERSION [RELEASE] Released version 2.7-dev3 2022-08-07 17:28:59 +02:00

The HAProxy documentation has been split into a number of different files for
ease of use.

Please refer to the following files depending on what you're looking for :

  - INSTALL for instructions on how to build and install HAProxy
  - BRANCHES to understand the project's life cycle and what version to use
  - LICENSE for the project's license
  - CONTRIBUTING for the process to follow to submit contributions

The more detailed documentation is located into the doc/ directory :

  - doc/intro.txt for a quick introduction on HAProxy
  - doc/configuration.txt for the configuration's reference manual
  - doc/lua.txt for the Lua's reference manual
  - doc/SPOE.txt for how to use the SPOE engine
  - doc/network-namespaces.txt for how to use network namespaces under Linux
  - doc/management.txt for the management guide
  - doc/regression-testing.txt for how to use the regression testing suite
  - doc/peers.txt for the peers protocol reference
  - doc/coding-style.txt for how to adopt HAProxy's coding style
  - doc/internals for developer-specific documentation (not all up to date)