[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>
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 @@
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
+/* Avoid doing 64 bit divide by 1000 */
+#define PSCHED_US2NS(x) ((s64)(x) << 10)
+#define PSCHED_NS2US(x) ((x) >> 10)
-#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_TICKS_PER_SEC PSCHED_NS2US(NSEC_PER_SEC)
+#define PSCHED_GET_TIME(stamp) \
+ ((stamp) = PSCHED_NS2US(ktime_to_ns(ktime_get())))
-#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)
+#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)
-#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(tv1, tv2) (long)((tv1) - (tv2))
#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)
-
-#define PSCHED_AUDIT_TDIFF(t) ({ if ((t) > 2000000) (t) = 2000000; })
-
-#else /* !CONFIG_NET_SCH_CLK_GETTIMEOFDAY */
-
-#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;