| commit | 2653868a2731c2282628472587e01460dd71cc2f | |
| author | Ludovic Henry <ludovic@xamarin.com> | |
| Mon, 9 May 2016 22:32:50 +0000 (9 18:32 -0400) | ||
| committer | Ludovic Henry <ludovic@xamarin.com> | |
| Mon, 9 May 2016 23:10:43 +0000 (9 19:10 -0400) | ||
| tree | 10d0315cdd77b479e6dd198b3bf31cad57f6fa66 | treesnapshot (tar.gz zip) |
| parent | 65ab352de4d4818baa4b167a1bbb0c45e0062c99 | commitdiff |
[threads] Fix reset blocking state transition
There would previously be a race between reset blocking and a STW, that would happen as follow:
- T1 goes into blocking - T1 state is BLOCKING(0)
- T2 suspends T1 - T1 state is BLOCKING(1)
- T1 does a reset blocking -> T1 state is SELF SUSPEND REQUESTED
- T2 calls `mono_thread_info_get_suspend_state` on T1 --- SIGABRT as we cannot get suspend state when state is SELF SUSPEND REQUESTED
- T1 does polling -> T1 state is SELF SUSPENDED
The fix is for reset blocking to work like done blocking: switch to BLOCKING AND SUSPENDED.
There would previously be a race between reset blocking and a STW, that would happen as follow:
- T1 goes into blocking - T1 state is BLOCKING(0)
- T2 suspends T1 - T1 state is BLOCKING(1)
- T1 does a reset blocking -> T1 state is SELF SUSPEND REQUESTED
- T2 calls `mono_thread_info_get_suspend_state` on T1 --- SIGABRT as we cannot get suspend state when state is SELF SUSPEND REQUESTED
- T1 does polling -> T1 state is SELF SUSPENDED
The fix is for reset blocking to work like done blocking: switch to BLOCKING AND SUSPENDED.
| mono/utils/mono-threads-coop.c | diffblobblamehistory | |
| mono/utils/mono-threads-state-machine.c | diffblobblamehistory | |
| mono/utils/mono-threads.h | diffblobblamehistory |