Re: [PATCH 2/2] winepulse.drv: Make timer delay more accurate.

[Andrew Eikum]

Signed-off-by: Andrew Eikum

On Sat, Mar 06, 2021 at 02:27:14AM +0100, Torge Matthies wrote:
> Signed-off-by: Torge Matthies
>
> This patch makes the pause in the loop of the audio thread more accurate.
> Sleep() may not be accurate enough for low-latency applications, and may pause
> execution either for too long or not at all.
> NtDelayExecution is an internal, undocumented function, but winepulse.drv is a
> Wine-internal module too so it should be fine imo.
>
> dlls/winepulse.drv/mmdevdrv.c | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/dlls/winepulse.drv/mmdevdrv.c b/dlls/winepulse.drv/mmdevdrv.c
> index 4609b2851ed..10b01868a9d 100644
> --- a/dlls/winepulse.drv/mmdevdrv.c
> +++ b/dlls/winepulse.drv/mmdevdrv.c
> @@ -38,6 +38,7 @@
>  #include "winbase.h"
>  #include "winnls.h"
>  #include "winreg.h"
> +#include "winternl.h"
>  #include "wine/debug.h"
>  #include "wine/unicode.h"
>  #include "wine/list.h"
> @@ -1021,14 +1022,14 @@ static void pulse_read(ACImpl *This)
>
> static DWORD WINAPI pulse_timer_cb(void *user)
>  {
> - DWORD delay;
> -
>
> LARGE_INTEGER delay;
> UINT32 adv_bytes;
> ACImpl *This = user;
> int success;
> pa_operation *o;
>
> pthread_mutex_lock(&pulse_lock);
> - delay = This->mmdev_period_usec / 1000;
> - delay.QuadPart = -This->mmdev_period_usec * 10;
> pa_stream_get_time(This->stream, &This->last_time);
> pthread_mutex_unlock(&pulse_lock);
>
> @@ -1036,11 +1037,11 @@ static DWORD WINAPI pulse_timer_cb(void *user)
>          pa_usec_t now, adv_usec = 0;
>          int err;
> -
>    Sleep(delay);
> -
>    NtDelayExecution(FALSE, &delay);
>
>    pthread_mutex_lock(&pulse_lock);
>
> -
>    delay = This->mmdev_period_usec / 1000;
> -
>    delay.QuadPart = -This->mmdev_period_usec * 10;
>
>    o = pa_stream_update_timing_info(This->stream, pulse_op_cb, &success);
>    if (o)
>
> @@ -1076,7 +1077,7 @@ static DWORD WINAPI pulse_timer_cb(void *user)
>                      else if(adjust < -((INT32)(This->mmdev_period_usec / 2)))
>                          adjust = -1 * This->mmdev_period_usec / 2;
> -
>                delay = (This->mmdev_period_usec + adjust) / 1000;
> -
>                delay.QuadPart = -(This->mmdev_period_usec + adjust) * 10;
>
>                This->last_time += This->mmdev_period_usec;
>            }
>
> @@ -1094,16 +1095,16 @@ static DWORD WINAPI pulse_timer_cb(void *user)
>                  }
>              }else{
>                  This->last_time = now;
> -
>            delay = This->mmdev_period_usec / 1000;
> -
>            delay.QuadPart = -This->mmdev_period_usec * 10;
>        }
>    }
>
>    if (This->event)
>        SetEvent(This->event);
>
> -
>    TRACE("%p after update, adv usec: %d, held: %u, delay: %u\n",
> -
>    TRACE("%p after update, adv usec: %d, held: %u, delay usec: %u\n",
>            This, (int)adv_usec,
> -
>            (int)(This->held_bytes/ pa_frame_size(&This->ss)), delay);
> -
>            (int)(This->held_bytes/ pa_frame_size(&This->ss)), (unsigned int)(-delay.QuadPart / 10));
>
>    pthread_mutex_unlock(&pulse_lock);
>
> }
>
> -- 
> 2.30.1