[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>

1 files changed, 2 insertions, 75 deletions

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index 4a927a5e1fa6..d71bf79eb80b 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -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