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[DCCP] ccid3: Replace scaled division operations

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This replaces the remaining uses of usecs_div with scaled_div32, which
internally uses 64bit division and produces a warning on overflow.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This commit is contained in:
Gerrit Renker 2006-12-10 00:02:51 -02:00 committed by David S. Miller
parent 1a21e49a8d
commit b9039a2a8d
1 changed files with 3 additions and 24 deletions
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27
net/dccp/ccids/ccid3.c
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@ -41,27 +41,6 @@
#include "lib/tfrc.h"
#include "ccid3.h"
/*
* Reason for maths here is to avoid 32 bit overflow when a is big.
* With this we get close to the limit.
*/
static u32 usecs_div(const u32 a, const u32 b)
{
const u32 div = a < (UINT_MAX / (USEC_PER_SEC / 10)) ? 10 :
a < (UINT_MAX / (USEC_PER_SEC / 50)) ? 50 :
a < (UINT_MAX / (USEC_PER_SEC / 100)) ? 100 :
a < (UINT_MAX / (USEC_PER_SEC / 500)) ? 500 :
a < (UINT_MAX / (USEC_PER_SEC / 1000)) ? 1000 :
a < (UINT_MAX / (USEC_PER_SEC / 5000)) ? 5000 :
a < (UINT_MAX / (USEC_PER_SEC / 10000)) ? 10000 :
a < (UINT_MAX / (USEC_PER_SEC / 50000)) ? 50000 :
100000;
const u32 tmp = a * (USEC_PER_SEC / div);
return (b >= 2 * div) ? tmp / (b / div) : tmp;
}
#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
static int ccid3_debug;
#define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a)
@ -731,8 +710,8 @@ static void ccid3_hc_rx_send_feedback(struct sock *sk)
case TFRC_RSTATE_DATA: {
const u32 delta = timeval_delta(&now,
&hcrx->ccid3hcrx_tstamp_last_feedback);
hcrx->ccid3hcrx_x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv,
delta);
hcrx->ccid3hcrx_x_recv =
scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
}
break;
case TFRC_RSTATE_TERM:
@ -862,7 +841,7 @@ found:
dccp_timestamp(sk, &tstamp);
delta = timeval_delta(&tstamp, &hcrx->ccid3hcrx_tstamp_last_feedback);
x_recv = usecs_div(hcrx->ccid3hcrx_bytes_recv, delta);
x_recv = scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
if (x_recv == 0)
x_recv = hcrx->ccid3hcrx_x_recv;