All of lore.kernel.org
 help / color / mirror / Atom feed
From: Santiago Carot-Nemesio <sancane@gmail.com>
To: linux-bluetooth@vger.kernel.org
Cc: Santiago Carot-Nemesio <sancane@gmail.com>
Subject: [PATCH 2/2] Remove magic numbers in MCAP CSP
Date: Wed, 22 Sep 2010 09:03:51 +0200	[thread overview]
Message-ID: <1285139031-1570-2-git-send-email-sancane@gmail.com> (raw)
In-Reply-To: <1285139031-1570-1-git-send-email-sancane@gmail.com>

---
 health/mcap_sync.c |   18 ++++++++++--------
 1 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/health/mcap_sync.c b/health/mcap_sync.c
index 3d54936..b9f2a65 100644
--- a/health/mcap_sync.c
+++ b/health/mcap_sync.c
@@ -48,6 +48,8 @@
 #define CLK CLOCK_MONOTONIC
 
 #define MCAP_CSP_ERROR g_quark_from_static_string("mcap-csp-error-quark")
+#define MAX_RETRIES	10
+#define SAMPLE_COUNT	20
 
 struct mcap_csp {
 	uint64_t	base_tmstamp;	/* CSP base timestamp */
@@ -363,7 +365,7 @@ uint32_t mcap_get_btclock(struct mcap_mcl *mcl)
 static gboolean initialize_caps(struct mcap_mcl *mcl)
 {
 	struct timespec t1, t2;
-	int latencies[20];
+	int latencies[SAMPLE_COUNT];
 	int latency, avg, dev;
 	uint32_t btclock;
 	uint16_t btaccuracy;
@@ -385,8 +387,8 @@ static gboolean initialize_caps(struct mcap_mcl *mcl)
 	/* Do clock read a number of times and measure latency */
 	avg = 0;
 	i = 0;
-	retries = 10;
-	while ((i < 20) && (retries > 0)) {
+	retries = MAX_RETRIES;
+	while ((i < SAMPLE_COUNT) && (retries > 0)) {
 		clock_gettime(CLK, &t1);
 		if (!read_btclock(mcl, &btclock, &btaccuracy)) {
 			retries--;
@@ -404,21 +406,21 @@ static gboolean initialize_caps(struct mcap_mcl *mcl)
 		return FALSE;
 
 	/* Calculate average and deviation */
-	avg /= 20;
+	avg /= SAMPLE_COUNT;
 	dev = 0;
-	for (i = 0; i < 20; ++i)
+	for (i = 0; i < SAMPLE_COUNT; ++i)
 		dev += abs(latencies[i] - avg);
-	dev /= 20;
+	dev /= SAMPLE_COUNT;
 
 	/* Calculate corrected average, without 'freak' latencies */
 	latency = 0;
-	for (i = 0; i < 20; ++i) {
+	for (i = 0; i < SAMPLE_COUNT; ++i) {
 		if (latencies[i] > (avg + dev * 6))
 			latency += avg;
 		else
 			latency += latencies[i];
 	}
-	latency /= 20;
+	latency /= SAMPLE_COUNT;
 
 	_caps.latency = latency;
 	_caps.preempt_thresh = latency * 4;
-- 
1.7.0.4


  reply	other threads:[~2010-09-22  7:03 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-09-22  7:03 [PATCH 1/2] Simplify logic to calculate the BT/system clock latency Santiago Carot-Nemesio
2010-09-22  7:03 ` Santiago Carot-Nemesio [this message]
2010-09-22  7:59   ` [PATCH 2/2] Remove magic numbers in MCAP CSP Johan Hedberg
2010-09-22  7:59 ` [PATCH 1/2] Simplify logic to calculate the BT/system clock latency Johan Hedberg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1285139031-1570-2-git-send-email-sancane@gmail.com \
    --to=sancane@gmail.com \
    --cc=linux-bluetooth@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.