[vdr] Re: vdr 1.3.18 cCondWait::SleepMs

[Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de>]

Ludwig Nussel wrote:
> Klaus Schmidinger wrote:
>
> > If you look at the places where cCondWait::SleepMs() is used, you'll
> > see that these are mainly situations where we just need to wait some
> > milliseconds, with no condition or whatever else to "wait on".
> >
> > Wherever it is feasible VDR does wait on conditions.
>
> What about this one?
>
> Index: vdr-1.3.18/dvbplayer.c
> ===================================================================
> --- vdr-1.3.18.orig/dvbplayer.c
> +++ vdr-1.3.18/dvbplayer.c
> @@ -191,6 +191,7 @@ private:
>    bool running;
>    bool firstPacket;
>    ePlayModes playMode;
> +  cCondVar playMode_condition;
>    ePlayDirs playDir;
>    int trickSpeed;
>    int readIndex, writeIndex;
> @@ -353,6 +354,7 @@ void cDvbPlayer::Activate(bool On)
>       }
>    else if (active) {
>       running = false;
> +     playMode_condition.Broadcast();
>       Cancel(3);
>       active = false;
>       }
> @@ -439,7 +441,7 @@ void cDvbPlayer::Action(void)
>                      }
>                   }
>                else
> -                 cCondWait::SleepMs(1); // this keeps the CPU load low
> +                 playMode_condition.Wait(mutex);
>                }
>  
>             // Store the frame in the buffer:
> @@ -521,6 +523,7 @@ void cDvbPlayer::Play(void)
>       DevicePlay();
>       playMode = pmPlay;
>       playDir = pdForward;
> +     playMode_condition.Broadcast();
>      }
>  }
>  
> Index: vdr-1.3.18/thread.h
> ===================================================================
> --- vdr-1.3.18.orig/thread.h
> +++ vdr-1.3.18/thread.h
> @@ -75,11 +75,11 @@ class cThread {
>  private:
>    bool running;
>    pthread_t childTid;
> -  cMutex mutex;
>    char *description;
>    static bool emergencyExitRequested;
>    static void *StartThread(cThread *Thread);
>  protected:
> +  cMutex mutex;
>    void Lock(void) { mutex.Lock(); }
>    void Unlock(void) { mutex.Unlock(); }
>    virtual void Action(void) = 0;
>
> cu
> Ludwig
Why so complicated?
All that needs to be done is to wait a little while at this point,
making sure the time slice will be given up. It doesn't really matter
whether we wait 1, 2 or 3 milliseconds - even 10 would be ok here.

I'll change the time to 3ms, which, according to what I've seen in other
postings, should not cause a busy wait.

Klaus