c8ab5f2a13
End lockd's grace period using schedule_delayed_work() instead of a check on every pass through the main loop. After a later patch, we'll depend on lockd to end its grace period even if it's not currently handling requests; so it shouldn't depend on being woken up from the main loop to do so. Also, Nakano Hiroaki (who independently produced a similar patch) noticed that the current behavior is buggy in the face of jiffies wraparound: "lockd uses time_before() to determine whether the grace period has expired. This would seem to be enough to avoid timer wrap-around issues, but, unfortunately, that is not the case. The time_* family of comparison functions can be safely used to compare jiffies relatively close in time, but they stop working after approximately LONG_MAX/2 ticks. nfsd can suffer this problem because the time_before() comparison in lockd() is not performed until the first request comes in, which means that if there is no lockd traffic for more than LONG_MAX/2 ticks we are screwed. "The implication of this is that once time_before() starts misbehaving any attempt from a NFS client to execute fcntl() will be received with a NLM_LCK_DENIED_GRACE_PERIOD message for 25 days (assuming HZ=1000). In other words, the 50 seconds grace period could turn into a grace period of 50 days or more. "Note: This bug was analyzed independently by Oda-san <oda@valinux.co.jp> and myself." Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Nakano Hiroaki <nakano.hiroaki@oss.ntt.co.jp> Cc: Itsuro Oda <oda@valinux.co.jp> |
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| .. | ||
| Makefile | ||
| clntlock.c | ||
| clntproc.c | ||
| host.c | ||
| mon.c | ||
| svc.c | ||
| svc4proc.c | ||
| svclock.c | ||
| svcproc.c | ||
| svcshare.c | ||
| svcsubs.c | ||
| xdr.c | ||
| xdr4.c | ||