Introducing the function that does the ATM cell alignment, and
modifying tc_calc_rtable() to use this based upon a linklayer
parameter.
Modified from original to use constants from atm.h and
fix all the usages of rtable in same patch.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
For CBQ, implement overhead parameter parsing.
The change is ABI (Application Binary Interface) backward compatible
with older kernels, but will first have effect from kernel 2.6.24.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>
Change CBQ to use matches() function instead of strcmp().
This resembels the usage in other parse functions, and allows
partial command parameter matching.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>
Change tc_calc_rtable() to take a tc_ratespec struct as an
argument. (cell_log still needs to be passed on as a parameter,
because -1 indicate that the cell_log needs to be computed by the
function.).
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>
[IPROUTE]: Add sprint_ticks() function and use in CBQ
Add helper function to print ticks to avoid assumptions about clock
resolution in CBQ.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
[IPROUTE]: Replace "usec" by "time" in function names
Rename functions containing "usec" since they don't necessarily return
usec units anymore.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
[IPROUTE]: Use tc_calc_xmittime() where appropriate
Replace expressions of the form "tc_core_usec2tick(1000000 * size/rate)"
by tc_calc_xmittime().
The CBQ case deserves an extra comment: when called with bnwd=rate,
tc_cbq_calc_maxidle() behaves identical to tc_calc_xmittime():
unsigned tc_cbq_calc_maxidle(...)
{
double g = 1.0 - 1.0/(1<<ewma_log);
double xmt = (double)avpkt/bndw;
maxidle = xmt*(1-g);
if (bndw != rate && maxburst) {
...
}
return tc_core_usec2tick(maxidle*(1<<ewma_log)*1000000);
}
which comes down to:
maxidle = xmt * (1 - g)
= xmt * (1 - (1.0 - 1.0/(1 << ewma_log))
= xmt * (1.0/(1 << ewma_log))
so:
maxidle * (1 << ewma_log) * 1000000
= xmt * (1.0/(1 << ewma_log)) * (1 << ewma_log) * 1000000
= xmt * 1000000
= avpkt/bndw * 1000000
Which means tc_core_usec2tick(maxidle*(1<<ewma_log)*1000000) is identical
to tc_calc_xmittime(bndw, avpkt). Use it directly since its a lot easier
to understand its limits.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
