[src/netbsd-8]: src/sys/dev/pad Pull up following revision(s) (requested by n...

[snj <snj%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/bc4c848ed6e9
branches:  netbsd-8
changeset: 433990:bc4c848ed6e9
user:      snj <snj%NetBSD.org@localhost>
date:      Sat Jun 10 06:05:47 2017 +0000

description:
Pull up following revision(s) (requested by nat in ticket #20):
        sys/dev/pad/pad.c: revisions 1.33-1.35
        sys/dev/pad/padvar.h: revision 1.9
Express BYTESTOSLEEP as an 64 bit integer.
Use BYTESTOSLEEP in expresson of BYTES_PER_SEC.
--
sc_bytes_count needs to be set in pad_audio_open not pad_open.
--
Simplification of rate limiter.  It now works uni/multiprocessor.
--
pad blocksize 1024 -> 8192.  Helps when sleeping in rate limiter.

diffstat:

 sys/dev/pad/pad.c    |  33 +++++++++++++--------------------
 sys/dev/pad/padvar.h |   4 ++--
 2 files changed, 15 insertions(+), 22 deletions(-)

diffs (105 lines):

diff -r 86440791db2c -r bc4c848ed6e9 sys/dev/pad/pad.c
--- a/sys/dev/pad/pad.c Sat Jun 10 05:57:08 2017 +0000
+++ b/sys/dev/pad/pad.c Sat Jun 10 06:05:47 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: pad.c,v 1.32 2017/06/01 09:44:30 pgoyette Exp $ */
+/* $NetBSD: pad.c,v 1.32.2.1 2017/06/10 06:05:47 snj Exp $ */
 
 /*-
  * Copyright (c) 2007 Jared D. McNeill <jmcneill%invisible.ca@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pad.c,v 1.32 2017/06/01 09:44:30 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pad.c,v 1.32.2.1 2017/06/10 06:05:47 snj Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -322,10 +322,6 @@
                return EBUSY;
        }
        
-       getmicrotime(&sc->sc_last);
-       sc->sc_bytes_count = 0;
-       sc->sc_remainder = 0;
-
        return 0;
 }
 
@@ -345,8 +341,8 @@
 }
 
 #define PAD_BYTES_PER_SEC   (44100 * sizeof(int16_t) * 2)
-#define TIMENEXTREAD       (PAD_BLKSIZE * 1000000 / PAD_BYTES_PER_SEC)
-#define BYTESTOSLEEP       (PAD_BLKSIZE)
+#define BYTESTOSLEEP       (int64_t)(PAD_BLKSIZE)
+#define TIMENEXTREAD       (int64_t)(BYTESTOSLEEP * 1000000 / PAD_BYTES_PER_SEC)
 
 int
 pad_read(dev_t dev, struct uio *uio, int flags)
@@ -374,10 +370,11 @@
                nowusec = (now.tv_sec * 1000000) + now.tv_usec;
                lastusec = (sc->sc_last.tv_sec * 1000000) +
                     sc->sc_last.tv_usec;
-               if (lastusec + TIMENEXTREAD > nowusec &&
-                    sc->sc_bytes_count >= BYTESTOSLEEP) {
-                       sc->sc_remainder +=
-                           ((lastusec + TIMENEXTREAD) - nowusec);
+               if (lastusec + TIMENEXTREAD > nowusec) {
+                       if (sc->sc_bytes_count >= BYTESTOSLEEP) {
+                               sc->sc_remainder +=
+                                   ((lastusec + TIMENEXTREAD) - nowusec);
+                       }
                        
                        wait_ticks = (hz * sc->sc_remainder) / 1000000;
                        if (wait_ticks > 0) {
@@ -385,19 +382,14 @@
                                kpause("padwait", TRUE, wait_ticks,
                                    &sc->sc_lock);
                        }
+               }
 
-                       sc->sc_bytes_count -= BYTESTOSLEEP;
-                       getmicrotime(&sc->sc_last);
-               } else if (sc->sc_bytes_count >= BYTESTOSLEEP) {
+               if (sc->sc_bytes_count >= BYTESTOSLEEP)
                        sc->sc_bytes_count -= BYTESTOSLEEP;
-                       getmicrotime(&sc->sc_last);
-               } else if (lastusec + TIMENEXTREAD <= nowusec) {
-                       getmicrotime(&sc->sc_last);
-                       sc->sc_remainder = 0;
-               }
 
                err = pad_get_block(sc, &pb, min(uio->uio_resid, PAD_BLKSIZE));
                if (!err) {
+                       getmicrotime(&sc->sc_last);
                        sc->sc_bytes_count += pb.pb_len;
                        mutex_exit(&sc->sc_lock);
                        err = uiomove(pb.pb_ptr, pb.pb_len, uio);
@@ -438,6 +430,7 @@
                return EIO;
 
        getmicrotime(&sc->sc_last);
+       sc->sc_bytes_count = 0;
        sc->sc_remainder = 0;
 
        return 0;
diff -r 86440791db2c -r bc4c848ed6e9 sys/dev/pad/padvar.h
--- a/sys/dev/pad/padvar.h      Sat Jun 10 05:57:08 2017 +0000
+++ b/sys/dev/pad/padvar.h      Sat Jun 10 06:05:47 2017 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: padvar.h,v 1.8 2017/05/27 10:02:26 nat Exp $ */
+/* $NetBSD: padvar.h,v 1.8.2.1 2017/06/10 06:05:47 snj Exp $ */
 
 /*-
  * Copyright (c) 2007 Jared D. McNeill <jmcneill%invisible.ca@localhost>
@@ -44,7 +44,7 @@
        struct audio_softc *sc_audiodev;
        int             sc_blksize;
 
-#define PAD_BLKSIZE    1024
+#define PAD_BLKSIZE    8192
 #define PAD_BUFSIZE    65536
        uint8_t         sc_audiobuf[PAD_BUFSIZE];
        uint32_t        sc_buflen;