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| author | Randolph Tan <randolph@10gen.com> | 2014-04-15 13:58:21 -0400 |
|---|---|---|
| committer | Randolph Tan <randolph@10gen.com> | 2014-04-17 11:07:03 -0400 |
| commit | 5e737823b0cd4e56e894fb504c406caa28d8fd34 (patch) | |
| tree | 7fef0b4a786830dabb6f769bf68ede90e3dc2f22 /src/mongo/s/distlock.h | |
| parent | 9ec25e399fc775361ed37fd5abb78960659a308b (diff) | |
| download | mongo-5e737823b0cd4e56e894fb504c406caa28d8fd34.tar.gz | |
SERVER-13585 Race in dist lock after winning "tournament" round
Remove the potential state transition from 1 to 0.
Diffstat (limited to 'src/mongo/s/distlock.h')
| -rw-r--r-- | src/mongo/s/distlock.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/src/mongo/s/distlock.h b/src/mongo/s/distlock.h index 583460fdf54..75595dc273a 100644 --- a/src/mongo/s/distlock.h +++ b/src/mongo/s/distlock.h @@ -71,6 +71,19 @@ namespace mongo { * (1) remembering the ping document time along with config server time when unable to * take a lock, and (2) ensuring all config servers report similar times and have similar * time rates (the difference in times must start and stay small). + * + * Lock states include: + * 0: unlocked + * 1: about to be locked + * 2: locked + * + * Valid state transitions: + * 0 -> 1 + * 1 -> 2 + * 2 -> 0 + * + * Note that at any point in time, a lock can be force unlocked if the ping for the lock + * becomes too stale. */ class MONGO_CLIENT_API DistributedLock { public: |