mirror of
http://git.haproxy.org/git/haproxy.git/
synced 2024-12-11 22:15:14 +00:00
2970b0bedf
Some freq counters will have to work on periods different from 1 second. The original freq counters rely on the period to be exactly one second. The new ones (freq_ctr_period) let the user define the period in ticks, and all computations are operated over that period. When reading a value, it indicates the amount of events over that period too.
126 lines
4.3 KiB
C
126 lines
4.3 KiB
C
/*
|
|
include/proto/freq_ctr.h
|
|
This file contains macros and inline functions for frequency counters.
|
|
|
|
Copyright (C) 2000-2009 Willy Tarreau - w@1wt.eu
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation, version 2.1
|
|
exclusively.
|
|
|
|
This library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#ifndef _PROTO_FREQ_CTR_H
|
|
#define _PROTO_FREQ_CTR_H
|
|
|
|
#include <common/config.h>
|
|
#include <common/time.h>
|
|
#include <types/freq_ctr.h>
|
|
|
|
/* Rotate a frequency counter when current period is over. Must not be called
|
|
* during a valid period. It is important that it correctly initializes a null
|
|
* area.
|
|
*/
|
|
static inline void rotate_freq_ctr(struct freq_ctr *ctr)
|
|
{
|
|
ctr->prev_ctr = ctr->curr_ctr;
|
|
if (likely(now.tv_sec - ctr->curr_sec != 1)) {
|
|
/* we missed more than one second */
|
|
ctr->prev_ctr = 0;
|
|
}
|
|
ctr->curr_sec = now.tv_sec;
|
|
ctr->curr_ctr = 0; /* leave it at the end to help gcc optimize it away */
|
|
}
|
|
|
|
/* Update a frequency counter by <inc> incremental units. It is automatically
|
|
* rotated if the period is over. It is important that it correctly initializes
|
|
* a null area.
|
|
*/
|
|
static inline void update_freq_ctr(struct freq_ctr *ctr, unsigned int inc)
|
|
{
|
|
if (likely(ctr->curr_sec == now.tv_sec)) {
|
|
ctr->curr_ctr += inc;
|
|
return;
|
|
}
|
|
rotate_freq_ctr(ctr);
|
|
ctr->curr_ctr = inc;
|
|
/* Note: later we may want to propagate the update to other counters */
|
|
}
|
|
|
|
/* Rotate a frequency counter when current period is over. Must not be called
|
|
* during a valid period. It is important that it correctly initializes a null
|
|
* area. This one works on frequency counters which have a period different
|
|
* from one second.
|
|
*/
|
|
static inline void rotate_freq_ctr_period(struct freq_ctr_period *ctr,
|
|
unsigned int period)
|
|
{
|
|
ctr->prev_ctr = ctr->curr_ctr;
|
|
ctr->curr_tick += period;
|
|
if (likely(now_ms - ctr->curr_tick >= period)) {
|
|
/* we missed at least two periods */
|
|
ctr->prev_ctr = 0;
|
|
ctr->curr_tick = now_ms;
|
|
}
|
|
ctr->curr_ctr = 0; /* leave it at the end to help gcc optimize it away */
|
|
}
|
|
|
|
/* Update a frequency counter by <inc> incremental units. It is automatically
|
|
* rotated if the period is over. It is important that it correctly initializes
|
|
* a null area. This one works on frequency counters which have a period
|
|
* different from one second.
|
|
*/
|
|
static inline void update_freq_ctr_period(struct freq_ctr_period *ctr,
|
|
unsigned int period, unsigned int inc)
|
|
{
|
|
if (likely(now_ms - ctr->curr_tick < period)) {
|
|
ctr->curr_ctr += inc;
|
|
return;
|
|
}
|
|
rotate_freq_ctr_period(ctr, period);
|
|
ctr->curr_ctr = inc;
|
|
/* Note: later we may want to propagate the update to other counters */
|
|
}
|
|
|
|
/* Read a frequency counter taking history into account for missing time in
|
|
* current period.
|
|
*/
|
|
unsigned int read_freq_ctr(struct freq_ctr *ctr);
|
|
|
|
/* returns the number of remaining events that can occur on this freq counter
|
|
* while respecting <freq> and taking into account that <pend> events are
|
|
* already known to be pending. Returns 0 if limit was reached.
|
|
*/
|
|
unsigned int freq_ctr_remain(struct freq_ctr *ctr, unsigned int freq, unsigned int pend);
|
|
|
|
/* return the expected wait time in ms before the next event may occur,
|
|
* respecting frequency <freq>, and assuming there may already be some pending
|
|
* events. It returns zero if we can proceed immediately, otherwise the wait
|
|
* time, which will be rounded down 1ms for better accuracy, with a minimum
|
|
* of one ms.
|
|
*/
|
|
unsigned int next_event_delay(struct freq_ctr *ctr, unsigned int freq, unsigned int pend);
|
|
|
|
/* process freq counters over configurable periods */
|
|
unsigned int read_freq_ctr_period(struct freq_ctr_period *ctr, unsigned int period);
|
|
unsigned int freq_ctr_remain_period(struct freq_ctr_period *ctr, unsigned int period,
|
|
unsigned int freq, unsigned int pend);
|
|
|
|
#endif /* _PROTO_FREQ_CTR_H */
|
|
|
|
/*
|
|
* Local variables:
|
|
* c-indent-level: 8
|
|
* c-basic-offset: 8
|
|
* End:
|
|
*/
|