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[NET_SCHED]: Use ktime as clocksource

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Get rid of the manual clock source selection mess and use ktime. Also
use a scalar representation, which allows to clean up pkt_sched.h a bit
more and results in less ktime_to_ns() calls in most cases.

The PSCHED_US2JIFFIE/PSCHED_JIFFIE2US macros are implemented quite
inefficient by this patch, following patches will convert all qdiscs
to hrtimers and get rid of them entirely.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy
2007-03-16 01:18:42 -07:00
committed by David S. Miller
parent ddc7b8e32b
commit 641b9e0e8b
5 changed files with 19 additions and 315 deletions
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77
net/sched/sch_api.c
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@@ -1175,15 +1175,12 @@ reclassify:
return -1;
}
static int psched_us_per_tick = 1;
static int psched_tick_per_us = 1;
#ifdef CONFIG_PROC_FS
static int psched_show(struct seq_file *seq, void *v)
{
seq_printf(seq, "%08x %08x %08x %08x\n",
psched_tick_per_us, psched_us_per_tick,
1000000, HZ);
(u32)NSEC_PER_USEC, (u32)PSCHED_US2NS(1),
1000000, HZ);
return 0;
}
@@ -1202,80 +1199,10 @@ static const struct file_operations psched_fops = {
};
#endif
#ifdef CONFIG_NET_SCH_CLK_CPU
psched_tdiff_t psched_clock_per_hz;
int psched_clock_scale;
EXPORT_SYMBOL(psched_clock_per_hz);
EXPORT_SYMBOL(psched_clock_scale);
psched_time_t psched_time_base;
cycles_t psched_time_mark;
EXPORT_SYMBOL(psched_time_mark);
EXPORT_SYMBOL(psched_time_base);
/*
* Periodically adjust psched_time_base to avoid overflow
* with 32-bit get_cycles(). Safe up to 4GHz CPU.
*/
static void psched_tick(unsigned long);
static DEFINE_TIMER(psched_timer, psched_tick, 0, 0);
static void psched_tick(unsigned long dummy)
{
if (sizeof(cycles_t) == sizeof(u32)) {
psched_time_t dummy_stamp;
PSCHED_GET_TIME(dummy_stamp);
psched_timer.expires = jiffies + 1*HZ;
add_timer(&psched_timer);
}
}
int __init psched_calibrate_clock(void)
{
psched_time_t stamp, stamp1;
struct timeval tv, tv1;
psched_tdiff_t delay;
long rdelay;
unsigned long stop;
psched_tick(0);
stop = jiffies + HZ/10;
PSCHED_GET_TIME(stamp);
do_gettimeofday(&tv);
while (time_before(jiffies, stop)) {
barrier();
cpu_relax();
}
PSCHED_GET_TIME(stamp1);
do_gettimeofday(&tv1);
delay = PSCHED_TDIFF(stamp1, stamp);
rdelay = tv1.tv_usec - tv.tv_usec;
rdelay += (tv1.tv_sec - tv.tv_sec)*1000000;
if (rdelay > delay)
return -1;
delay /= rdelay;
psched_tick_per_us = delay;
while ((delay>>=1) != 0)
psched_clock_scale++;
psched_us_per_tick = 1<<psched_clock_scale;
psched_clock_per_hz = (psched_tick_per_us*(1000000/HZ))>>psched_clock_scale;
return 0;
}
#endif
static int __init pktsched_init(void)
{
struct rtnetlink_link *link_p;
#ifdef CONFIG_NET_SCH_CLK_CPU
if (psched_calibrate_clock() < 0)
return -1;
#elif defined(CONFIG_NET_SCH_CLK_JIFFIES)
psched_tick_per_us = HZ<<PSCHED_JSCALE;
psched_us_per_tick = 1000000;
#endif
link_p = rtnetlink_links[PF_UNSPEC];
/* Setup rtnetlink links. It is made here to avoid