Module Name: src
Committed By: nat
Date: Tue Oct 31 21:09:27 UTC 2017
Modified Files:
src/sys/dev: audio.c
Log Message:
round_blocksize is only used for the hardware ring buffer. All other
buffers (mix ring, streams) are set to be a power of 2.
This allows for consistent latency where a static blocksize is enforced by
the underlying audio device driver.
Ok christos@.
To generate a diff of this commit:
cvs rdiff -u -r1.418 -r1.419 src/sys/dev/audio.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/audio.c
diff -u src/sys/dev/audio.c:1.418 src/sys/dev/audio.c:1.419
--- src/sys/dev/audio.c:1.418 Sat Oct 28 03:34:26 2017
+++ src/sys/dev/audio.c Tue Oct 31 21:09:26 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: audio.c,v 1.418 2017/10/28 03:34:26 riastradh Exp $ */
+/* $NetBSD: audio.c,v 1.419 2017/10/31 21:09:26 nat Exp $ */
/*-
* Copyright (c) 2016 Nathanial Sloss <nathanialsl...@yahoo.com.au>
@@ -148,7 +148,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: audio.c,v 1.418 2017/10/28 03:34:26 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: audio.c,v 1.419 2017/10/31 21:09:26 nat Exp $");
#ifdef _KERNEL_OPT
#include "audio.h"
@@ -2004,9 +2004,21 @@ audio_init_ringbuffer(struct audio_softc
blksize = rp->s.bufsize / AUMINNOBLK;
ROUNDSIZE(blksize);
DPRINTF(("audio_init_ringbuffer: MI blksize=%d\n", blksize));
- if (sc->hw_if->round_blocksize)
+
+ struct virtual_channel *hwvc = sc->sc_hwvc;
+ if (sc->hw_if->round_blocksize &&
+ (rp == &hwvc->sc_mpr || rp == &hwvc->sc_mrr)) {
blksize = sc->hw_if->round_blocksize(sc->hw_hdl, blksize,
- mode, &rp->s.param);
+ mode, &rp->s.param);
+ } else {
+ int tmpblksize = 1;
+ /* round blocksize to a power of 2 */
+ while (tmpblksize < blksize)
+ tmpblksize <<= 1;
+
+ blksize = tmpblksize;
+ }
+
if (blksize <= 0)
panic("audio_init_ringbuffer: blksize=%d", blksize);
nblks = rp->s.bufsize / blksize;
