[patch] snd hda suspend latency: shorten codec read

[Ingo Molnar]

snd hda suspend latency goes down a second via the patch below.

	Ingo

------------->
Subject: snd hda suspend latency: shorten codec read
From: Ingo Molnar <mingo@xxxxxxx>

not sleeping for every codec read/write but doing a short udelay and
a conditional reschedule has cut suspend+resume latency by about 1
second on my T60.

Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
 sound/pci/hda/hda_intel.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Index: linux/sound/pci/hda/hda_intel.c
===================================================================
--- linux.orig/sound/pci/hda/hda_intel.c
+++ linux/sound/pci/hda/hda_intel.c
@@ -555,7 +555,8 @@ static unsigned int azx_rirb_get_respons
 		}
 		if (!chip->rirb.cmds)
 			return chip->rirb.res; /* the last value */
-		schedule_timeout_uninterruptible(1);
+		udelay(10);
+		cond_resched();
 	} while (time_after_eq(timeout, jiffies));
 
 	if (chip->msi) {
-
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