On Thursday 20 August 2009 08:33:21 Takashi Iwai wrote:
At Wed, 19 Aug 2009 22:09:50 +0200, Bartlomiej Zolnierkiewicz wrote:
From: Bartlomiej Zolnierkiewicz bzolnier@gmail.com Subject: [PATCH] ali5451: fix timeout handling in snd_ali_{codecs,timer}_ready()
Modify loops in such way that the register value is checked also after the timeout condition, just in case the heavy interrupt load etc. caused the thread to sleep for the time period exceeding the timeout value.
While at it remove an extra ALI_STIMER read from snd_ali_stimer_ready().
Reported-by: Jack Byer ojbyer@usa.net Signed-off-by: Bartlomiej Zolnierkiewicz bzolnier@gmail.com
sound/pci/ali5451/ali5451.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
Index: b/sound/pci/ali5451/ali5451.c
--- a/sound/pci/ali5451/ali5451.c +++ b/sound/pci/ali5451/ali5451.c @@ -314,8 +314,11 @@ static int snd_ali_codec_ready(struct sn res = snd_ali_5451_peek(codec,port); if (!(res & 0x8000)) return 0;
if (!time_after_eq(end_time, jiffies))break;
- } while (time_after_eq(end_time, jiffies));
- } while (1);
Using for (;;) is more generic. I see your patch keeps the changes minimal, but I'm afraid that the result, do {} while(1), can be misleading.
Could you replace with for (;;) ?
Sure, though I don't see a much value added from this operation..
From: Bartlomiej Zolnierkiewicz bzolnier@gmail.com Subject: [PATCH v2] ali5451: fix timeout handling in snd_ali_{codecs,timer}_ready()
Modify loops in such way that the register value is checked also after the timeout condition, just in case the heavy interrupt load etc. caused the thread to sleep for the time period exceeding the timeout value.
While at it remove an extra ALI_STIMER read from snd_ali_stimer_ready().
Reported-by: Jack Byer ojbyer@usa.net Signed-off-by: Bartlomiej Zolnierkiewicz bzolnier@gmail.com --- sound/pci/ali5451/ali5451.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)
Index: b/sound/pci/ali5451/ali5451.c =================================================================== --- a/sound/pci/ali5451/ali5451.c +++ b/sound/pci/ali5451/ali5451.c @@ -310,12 +310,16 @@ static int snd_ali_codec_ready(struct sn unsigned int res; end_time = jiffies + msecs_to_jiffies(250); - do { + + for (;;) { res = snd_ali_5451_peek(codec,port); if (!(res & 0x8000)) return 0; + if (!time_after_eq(end_time, jiffies)) + break; schedule_timeout_uninterruptible(1); - } while (time_after_eq(end_time, jiffies)); + } + snd_ali_5451_poke(codec, port, res & ~0x8000); snd_printdd("ali_codec_ready: codec is not ready.\n "); return -EIO; @@ -327,15 +331,17 @@ static int snd_ali_stimer_ready(struct s unsigned long dwChk1,dwChk2; dwChk1 = snd_ali_5451_peek(codec, ALI_STIMER); - dwChk2 = snd_ali_5451_peek(codec, ALI_STIMER); - end_time = jiffies + msecs_to_jiffies(250); - do { + + for (;;) { dwChk2 = snd_ali_5451_peek(codec, ALI_STIMER); if (dwChk2 != dwChk1) return 0; + if (!time_after_eq(end_time, jiffies)) + break; schedule_timeout_uninterruptible(1); - } while (time_after_eq(end_time, jiffies)); + } + snd_printk(KERN_ERR "ali_stimer_read: stimer is not ready.\n"); return -EIO; }