[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Minios-devel] [PATCH] mini-os: Fix date issue in gettimeofday function
Hello, David Vercauteren, on Wed 06 Apr 2016 16:49:25 +0200, wrote: > If an application makes use of the monotonic clock function before > the wallclock is updated (timer_handler function was not yet called), > the struct shadow_ts_version will not contain the correct value. > As a result the application will not display the correct date. Mmm, it's not the monotonic clock which poses problem, but reading shadow_ts.tv_nsec. I'd rather put that update_wallclock() inside gettimeofday since that's the only user of shadow_ts. Also, thinking again about this time computation, it seems odd to me that they are updated from the interrupt handler: what about when an interrupt happens in the middle of the gettimeofday() or monotonic_clock() call? Reads from shadow and shadow_ts don't seem safe to me. In the end, I'm tempted to do the attached changes (not tested yet) Last but not least, I'm surprised by what gettimeofday does: it adds system_time to (time since boot) to wc_sec (wallclock time), it looks to me like this ends up with time going two times faster! I have to leave for a concert, just leaving these notes here for now in case somebody determines how this system_time / wc_sec thing is supposed to work, in the meanwhile Samuel Attachment:
patch _______________________________________________ Minios-devel mailing list Minios-devel@xxxxxxxxxxxxxxxxxxxx http://lists.xenproject.org/cgi-bin/mailman/listinfo/minios-devel
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |