Bug 362 - Self suspend is racy
Summary: Self suspend is racy
Status: RESOLVED FIXED
Alias: None
Product: Runtime
Classification: Mono
Component: General ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2011-08-22 12:55 UTC by Rodrigo Kumpera
Modified: 2016-04-19 08:17 UTC (History)
1 user (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
RESOLVED FIXED

Description Rodrigo Kumpera 2011-08-22 12:55:02 UTC
Self suspend is racy in the way it makes the thread state available for others.

Right now we drop the thread lock before suspending, which creates a window into which the thread state say's it's suspended but, at the same, time it's not.

The solution is to atomically release the lock and wait for resume.

the decent way to do it is using a condvar, which requires us to move clr state management to MonoThreadInfo so a single lock can be used.
Comment 1 Rodrigo Kumpera 2016-04-19 08:17:44 UTC
This was fixed using a 2 stage self suspend