diff options
author | Patrick McHardy <kaber@trash.net> | 2007-03-16 08:18:42 (GMT) |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-26 05:26:04 (GMT) |
commit | 641b9e0e8b7f96425da6ce98f3361e3af0baee29 (patch) | |
tree | 2315fed3b4fd9df52a52464b9b1ce1561d403a87 /include/net/pkt_sched.h | |
parent | ddc7b8e32b22fe8b45d306b7d99472d4b560add6 (diff) | |
download | linux-641b9e0e8b7f96425da6ce98f3361e3af0baee29.tar.xz |
[NET_SCHED]: Use ktime as clocksource
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>
Diffstat (limited to 'include/net/pkt_sched.h')
-rw-r--r-- | include/net/pkt_sched.h | 169 |
1 files changed, 13 insertions, 156 deletions
diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index f6afee7..1c12afd 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -2,6 +2,7 @@ #define __NET_PKT_SCHED_H #include <linux/jiffies.h> +#include <linux/ktime.h> #include <net/sch_generic.h> struct qdisc_walker @@ -37,176 +38,32 @@ static inline void *qdisc_priv(struct Qdisc *q) The things are not so bad, because we may use artifical clock evaluated by integration of network data flow in the most critical places. - - Note: we do not use fastgettimeofday. - The reason is that, when it is not the same thing as - gettimeofday, it returns invalid timestamp, which is - not updated, when net_bh is active. */ -/* General note about internal clock. - - Any clock source returns time intervals, measured in units - close to 1usec. With source CONFIG_NET_SCH_CLK_GETTIMEOFDAY it is precisely - microseconds, otherwise something close but different chosen to minimize - arithmetic cost. Ratio usec/internal untis in form nominator/denominator - may be read from /proc/net/psched. - */ - - -#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY - -typedef struct timeval psched_time_t; -typedef long psched_tdiff_t; - -#define PSCHED_GET_TIME(stamp) do_gettimeofday(&(stamp)) -#define PSCHED_US2JIFFIE(usecs) usecs_to_jiffies(usecs) -#define PSCHED_JIFFIE2US(delay) jiffies_to_usecs(delay) - -#else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ - typedef u64 psched_time_t; typedef long psched_tdiff_t; -#ifdef CONFIG_NET_SCH_CLK_JIFFIES - -#if HZ < 96 -#define PSCHED_JSCALE 14 -#elif HZ >= 96 && HZ < 192 -#define PSCHED_JSCALE 13 -#elif HZ >= 192 && HZ < 384 -#define PSCHED_JSCALE 12 -#elif HZ >= 384 && HZ < 768 -#define PSCHED_JSCALE 11 -#elif HZ >= 768 -#define PSCHED_JSCALE 10 -#endif - -#define PSCHED_GET_TIME(stamp) ((stamp) = (get_jiffies_64()<<PSCHED_JSCALE)) -#define PSCHED_US2JIFFIE(delay) (((delay)+(1<<PSCHED_JSCALE)-1)>>PSCHED_JSCALE) -#define PSCHED_JIFFIE2US(delay) ((delay)<<PSCHED_JSCALE) - -#endif /* CONFIG_NET_SCH_CLK_JIFFIES */ -#ifdef CONFIG_NET_SCH_CLK_CPU -#include <asm/timex.h> - -extern psched_tdiff_t psched_clock_per_hz; -extern int psched_clock_scale; -extern psched_time_t psched_time_base; -extern cycles_t psched_time_mark; - -#define PSCHED_GET_TIME(stamp) \ -do { \ - cycles_t cur = get_cycles(); \ - if (sizeof(cycles_t) == sizeof(u32)) { \ - if (cur <= psched_time_mark) \ - psched_time_base += 0x100000000ULL; \ - psched_time_mark = cur; \ - (stamp) = (psched_time_base + cur)>>psched_clock_scale; \ - } else { \ - (stamp) = cur>>psched_clock_scale; \ - } \ -} while (0) -#define PSCHED_US2JIFFIE(delay) (((delay)+psched_clock_per_hz-1)/psched_clock_per_hz) -#define PSCHED_JIFFIE2US(delay) ((delay)*psched_clock_per_hz) - -#endif /* CONFIG_NET_SCH_CLK_CPU */ - -#endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ - -#ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY -#define PSCHED_TDIFF(tv1, tv2) \ -({ \ - int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \ - int __delta = (tv1).tv_usec - (tv2).tv_usec; \ - if (__delta_sec) { \ - switch (__delta_sec) { \ - default: \ - __delta = 0; \ - case 2: \ - __delta += USEC_PER_SEC; \ - case 1: \ - __delta += USEC_PER_SEC; \ - } \ - } \ - __delta; \ -}) - -static inline int -psched_tod_diff(int delta_sec, int bound) -{ - int delta; - - if (bound <= USEC_PER_SEC || delta_sec > (0x7FFFFFFF/USEC_PER_SEC)-1) - return bound; - delta = delta_sec * USEC_PER_SEC; - if (delta > bound || delta < 0) - delta = bound; - return delta; -} - -#define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \ -({ \ - int __delta_sec = (tv1).tv_sec - (tv2).tv_sec; \ - int __delta = (tv1).tv_usec - (tv2).tv_usec; \ - switch (__delta_sec) { \ - default: \ - __delta = psched_tod_diff(__delta_sec, bound); break; \ - case 2: \ - __delta += USEC_PER_SEC; \ - case 1: \ - __delta += USEC_PER_SEC; \ - case 0: \ - if (__delta > bound || __delta < 0) \ - __delta = bound; \ - } \ - __delta; \ -}) - -#define PSCHED_TLESS(tv1, tv2) (((tv1).tv_usec < (tv2).tv_usec && \ - (tv1).tv_sec <= (tv2).tv_sec) || \ - (tv1).tv_sec < (tv2).tv_sec) - -#define PSCHED_TADD2(tv, delta, tv_res) \ -({ \ - int __delta = (tv).tv_usec + (delta); \ - (tv_res).tv_sec = (tv).tv_sec; \ - while (__delta >= USEC_PER_SEC) { (tv_res).tv_sec++; __delta -= USEC_PER_SEC; } \ - (tv_res).tv_usec = __delta; \ -}) - -#define PSCHED_TADD(tv, delta) \ -({ \ - (tv).tv_usec += (delta); \ - while ((tv).tv_usec >= USEC_PER_SEC) { (tv).tv_sec++; \ - (tv).tv_usec -= USEC_PER_SEC; } \ -}) - -/* Set/check that time is in the "past perfect"; - it depends on concrete representation of system time - */ - -#define PSCHED_SET_PASTPERFECT(t) ((t).tv_sec = 0) -#define PSCHED_IS_PASTPERFECT(t) ((t).tv_sec == 0) +/* Avoid doing 64 bit divide by 1000 */ +#define PSCHED_US2NS(x) ((s64)(x) << 10) +#define PSCHED_NS2US(x) ((x) >> 10) -#define PSCHED_AUDIT_TDIFF(t) ({ if ((t) > 2000000) (t) = 2000000; }) +#define PSCHED_TICKS_PER_SEC PSCHED_NS2US(NSEC_PER_SEC) +#define PSCHED_GET_TIME(stamp) \ + ((stamp) = PSCHED_NS2US(ktime_to_ns(ktime_get()))) -#else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ +#define PSCHED_US2JIFFIE(usecs) usecs_to_jiffies(PSCHED_US2NS((usecs)) / NSEC_PER_USEC) +#define PSCHED_JIFFIE2US(delay) PSCHED_NS2US(jiffies_to_usecs((delay)) * NSEC_PER_USEC) -#define PSCHED_TDIFF(tv1, tv2) (long)((tv1) - (tv2)) +#define PSCHED_TDIFF(tv1, tv2) (long)((tv1) - (tv2)) #define PSCHED_TDIFF_SAFE(tv1, tv2, bound) \ - min_t(long long, (tv1) - (tv2), bound) - - -#define PSCHED_TLESS(tv1, tv2) ((tv1) < (tv2)) + min_t(long long, (tv1) - (tv2), bound) +#define PSCHED_TLESS(tv1, tv2) ((tv1) < (tv2)) #define PSCHED_TADD2(tv, delta, tv_res) ((tv_res) = (tv) + (delta)) -#define PSCHED_TADD(tv, delta) ((tv) += (delta)) +#define PSCHED_TADD(tv, delta) ((tv) += (delta)) #define PSCHED_SET_PASTPERFECT(t) ((t) = 0) #define PSCHED_IS_PASTPERFECT(t) ((t) == 0) #define PSCHED_AUDIT_TDIFF(t) -#endif /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */ - extern struct Qdisc_ops pfifo_qdisc_ops; extern struct Qdisc_ops bfifo_qdisc_ops; |