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From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
To: Intel-gfx@lists.freedesktop.org
Subject: [PATCH 0/2] drmtest: Fix hanging child processes
Date: Tue,  3 Dec 2013 16:44:53 +0000	[thread overview]
Message-ID: <1386089095-9966-1-git-send-email-tvrtko.ursulin@linux.intel.com> (raw)

From: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

It was observed both on Linux and Android that tests which
fork can sometimes hang failing to terminate child
processes.

This was eventually tracked down to race conditions in C
library implementations, all with regards to caching of
PID/TGID and TID values.

Solution is to revert the previous workaround, which closed
the race under glibc a bit, and ensure current values from
the kernel are used during timing sensitive periods.

This was tested under Android only but should be a generic fix.

Tvrtko Ursulin (2):
  Revert "lib/drmtest: ducttape over fork race"
  drmtest: Avoid wrong PID/TID after clone races

 lib/drmtest.c | 20 +++++++++-----------
 1 file changed, 9 insertions(+), 11 deletions(-)

-- 
1.8.4.3

             reply	other threads:[~2013-12-03 16:45 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-03 16:44 Tvrtko Ursulin [this message]
2013-12-03 16:44 ` [PATCH 1/2] Revert "lib/drmtest: ducttape over fork race" Tvrtko Ursulin
2013-12-03 16:44 ` [PATCH 2/2] drmtest: Avoid wrong PID/TID after clone races Tvrtko Ursulin
2013-12-03 16:59 ` [PATCH 0/2] drmtest: Fix hanging child processes Daniel Vetter

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