pktgen: convert to use ktime_t

The kernel ktime_t is a nice generic infrastructure for mananging
high resolution times, as is done in pktgen.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 84 insertions, 100 deletions

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index b7302e18764..bede00b5403 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -246,16 +246,14 @@ struct pktgen_dev {
         int max_pkt_size;       /* = ETH_ZLEN; */
         int pkt_overhead;       /* overhead for MPLS, VLANs, IPSEC etc */
         int nfrags;
-        __u32 delay_us;         /* Default delay */
-        __u32 delay_ns;
+        u64 delay;              /* nano-seconds */
+
         __u64 count;            /* Default No packets to send */
         __u64 sofar;            /* How many pkts we've sent so far */
         __u64 tx_bytes;         /* How many bytes we've transmitted */
         __u64 errors;           /* Errors when trying to transmit, pkts will be re-sent */
 
         /* runtime counters relating to clone_skb */
-        __u64 next_tx_us;       /* timestamp of when to tx next */
-        __u32 next_tx_ns;
 
         __u64 allocated_skbs;
         __u32 clone_count;
@@ -263,9 +261,11 @@ struct pktgen_dev {
                                  * Or a failed transmit of some sort?  This will keep
                                  * sequence numbers in order, for example.
                                  */
-        __u64 started_at;       /* micro-seconds */
-        __u64 stopped_at;       /* micro-seconds */
-        __u64 idle_acc;         /* micro-seconds */
+        ktime_t next_tx;
+        ktime_t started_at;
+        ktime_t stopped_at;
+        u64     idle_acc;       /* nano-seconds */
+
         __u32 seq_num;
 
         int clone_skb;          /* Use multiple SKBs during packet gen.  If this number
@@ -397,23 +397,20 @@ struct pktgen_thread {
 #define REMOVE 1
 #define FIND   0
 
-/** Convert to micro-seconds */
-static inline __u64 tv_to_us(const struct timeval *tv)
+static inline ktime_t ktime_now(void)
 {
-        __u64 us = tv->tv_usec;
-        us += (__u64) tv->tv_sec * (__u64) 1000000;
-        return us;
+        struct timespec ts;
+        ktime_get_ts(&ts);
+
+        return timespec_to_ktime(ts);
 }
 
-static __u64 getCurUs(void)
+/* This works even if 32 bit because of careful byte order choice */
+static inline int ktime_lt(const ktime_t cmp1, const ktime_t cmp2)
 {
-        struct timeval tv;
-        do_gettimeofday(&tv);
-        return tv_to_us(&tv);
+        return cmp1.tv64 < cmp2.tv64;
 }
 
-/* old include end */
-
 static const char version[] __initconst = VERSION;
 
 static int pktgen_remove_device(struct pktgen_thread *t, struct pktgen_dev *i);
@@ -510,9 +507,8 @@ static const struct file_operations pktgen_fops = {
 static int pktgen_if_show(struct seq_file *seq, void *v)
 {
         const struct pktgen_dev *pkt_dev = seq->private;
-        __u64 sa;
-        __u64 stopped;
-        __u64 now = getCurUs();
+        ktime_t stopped;
+        u64 idle;
 
         seq_printf(seq,
                    "Params: count %llu  min_pkt_size: %u  max_pkt_size: %u\n",
@@ -520,9 +516,8 @@ static int pktgen_if_show(struct seq_file *seq, void *v)
                    pkt_dev->max_pkt_size);
 
         seq_printf(seq,
-                   "     frags: %d  delay: %u  clone_skb: %d  ifname: %s\n",
-                   pkt_dev->nfrags,
-                   1000 * pkt_dev->delay_us + pkt_dev->delay_ns,
+                   "     frags: %d  delay: %llu  clone_skb: %d  ifname: %s\n",
+                   pkt_dev->nfrags, (unsigned long long) pkt_dev->delay,
                    pkt_dev->clone_skb, pkt_dev->odev->name);
 
         seq_printf(seq, "     flows: %u flowlen: %u\n", pkt_dev->cflows,
@@ -654,17 +649,21 @@ static int pktgen_if_show(struct seq_file *seq, void *v)
 
         seq_puts(seq, "\n");
 
-        sa = pkt_dev->started_at;
-        stopped = pkt_dev->stopped_at;
-        if (pkt_dev->running)
-                stopped = now;  /* not really stopped, more like last-running-at */
+        /* not really stopped, more like last-running-at */
+        stopped = pkt_dev->running ? ktime_now() : pkt_dev->stopped_at;
+        idle = pkt_dev->idle_acc;
+        do_div(idle, NSEC_PER_USEC);
 
         seq_printf(seq,
-                   "Current:\n     pkts-sofar: %llu  errors: %llu\n     started: %lluus  stopped: %lluus idle: %lluus\n",
+                   "Current:\n     pkts-sofar: %llu  errors: %llu\n",
                    (unsigned long long)pkt_dev->sofar,
-                   (unsigned long long)pkt_dev->errors, (unsigned long long)sa,
-                   (unsigned long long)stopped,
-                   (unsigned long long)pkt_dev->idle_acc);
+                   (unsigned long long)pkt_dev->errors);
+
+        seq_printf(seq,
+                   "     started: %lluus  stopped: %lluus idle: %lluus\n",
+                   (unsigned long long) ktime_to_us(pkt_dev->started_at),
+                   (unsigned long long) ktime_to_us(stopped),
+                   (unsigned long long) idle);
 
         seq_printf(seq,
                    "     seq_num: %d  cur_dst_mac_offset: %d  cur_src_mac_offset: %d\n",
@@ -950,15 +949,13 @@ static ssize_t pktgen_if_write(struct file *file,
                         return len;
                 }
                 i += len;
-                if (value == 0x7FFFFFFF) {
-                        pkt_dev->delay_us = 0x7FFFFFFF;
-                        pkt_dev->delay_ns = 0;
-                } else {
-                        pkt_dev->delay_us = value / 1000;
-                        pkt_dev->delay_ns = value % 1000;
-                }
-                sprintf(pg_result, "OK: delay=%u",
-                        1000 * pkt_dev->delay_us + pkt_dev->delay_ns);
+                if (value == 0x7FFFFFFF)
+                        pkt_dev->delay = ULLONG_MAX;
+                else
+                        pkt_dev->delay = (u64)value * NSEC_PER_USEC;
+
+                sprintf(pg_result, "OK: delay=%llu",
+                        (unsigned long long) pkt_dev->delay);
                 return count;
         }
         if (!strcmp(name, "udp_src_min")) {
@@ -2089,27 +2086,33 @@ static void pktgen_setup_inject(struct pktgen_dev *pkt_dev)
         pkt_dev->nflows = 0;
 }
 
-static void spin(struct pktgen_dev *pkt_dev, __u64 spin_until_us)
+static inline s64 delta_ns(ktime_t a, ktime_t b)
 {
-        __u64 start;
-        __u64 now;
+        return ktime_to_ns(ktime_sub(a, b));
+}
+
+static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
+{
+        ktime_t start, now;
+        s64 dt;
+
+        start = now = ktime_now();
 
-        start = now = getCurUs();
-        while (now < spin_until_us) {
+        while ((dt = delta_ns(spin_until, now)) > 0) {
                 /* TODO: optimize sleeping behavior */
-                if (spin_until_us - now > jiffies_to_usecs(1) + 1)
+                if (dt > TICK_NSEC)
                         schedule_timeout_interruptible(1);
-                else if (spin_until_us - now > 100) {
+                else if (dt > 100*NSEC_PER_USEC) {
                         if (!pkt_dev->running)
                                 return;
                         if (need_resched())
                                 schedule();
                 }
 
-                now = getCurUs();
+                now = ktime_now();
         }
 
-        pkt_dev->idle_acc += now - start;
+        pkt_dev->idle_acc += ktime_to_ns(ktime_sub(now, start));
 }
 
 static inline void set_pkt_overhead(struct pktgen_dev *pkt_dev)
@@ -3070,9 +3073,9 @@ static void pktgen_run(struct pktgen_thread *t)
                         pktgen_clear_counters(pkt_dev);
                         pkt_dev->running = 1;   /* Cranke yeself! */
                         pkt_dev->skb = NULL;
-                        pkt_dev->started_at = getCurUs();
-                        pkt_dev->next_tx_us = getCurUs();       /* Transmit immediately */
-                        pkt_dev->next_tx_ns = 0;
+                        pkt_dev->started_at =
+                                pkt_dev->next_tx = ktime_now();
+
                         set_pkt_overhead(pkt_dev);
 
                         strcpy(pkt_dev->result, "Starting");
@@ -3188,28 +3191,21 @@ static void pktgen_reset_all_threads(void)
 
 static void show_results(struct pktgen_dev *pkt_dev, int nr_frags)
 {
-        __u64 total_us, bps, mbps, pps, idle;
+        __u64 bps, mbps, pps;
         char *p = pkt_dev->result;
-
-        total_us = pkt_dev->stopped_at - pkt_dev->started_at;
-
-        idle = pkt_dev->idle_acc;
-
-        p += sprintf(p, "OK: %llu(c%llu+d%llu) usec, %llu (%dbyte,%dfrags)\n",
-                     (unsigned long long)total_us,
-                     (unsigned long long)(total_us - idle),
-                     (unsigned long long)idle,
+        ktime_t elapsed = ktime_sub(pkt_dev->stopped_at,
+                                    pkt_dev->started_at);
+        ktime_t idle = ns_to_ktime(pkt_dev->idle_acc);
+
+        p += sprintf(p, "OK: %llu(c%llu+d%llu) nsec, %llu (%dbyte,%dfrags)\n",
+                     (unsigned long long)ktime_to_us(elapsed),
+                     (unsigned long long)ktime_to_us(ktime_sub(elapsed, idle)),
+                     (unsigned long long)ktime_to_us(idle),
                      (unsigned long long)pkt_dev->sofar,
                      pkt_dev->cur_pkt_size, nr_frags);
 
-        pps = pkt_dev->sofar * USEC_PER_SEC;
-
-        while ((total_us >> 32) != 0) {
-                pps >>= 1;
-                total_us >>= 1;
-        }
-
-        do_div(pps, total_us);
+        pps = div64_u64(pkt_dev->sofar * NSEC_PER_SEC,
+                        ktime_to_ns(elapsed));
 
         bps = pps * 8 * pkt_dev->cur_pkt_size;
 
@@ -3235,7 +3231,7 @@ static int pktgen_stop_device(struct pktgen_dev *pkt_dev)
 
         kfree_skb(pkt_dev->skb);
         pkt_dev->skb = NULL;
-        pkt_dev->stopped_at = getCurUs();
+        pkt_dev->stopped_at = ktime_now();
         pkt_dev->running = 0;
 
         show_results(pkt_dev, nr_frags);
@@ -3254,7 +3250,7 @@ static struct pktgen_dev *next_to_run(struct pktgen_thread *t)
                         continue;
                 if (best == NULL)
                         best = pkt_dev;
-                else if (pkt_dev->next_tx_us < best->next_tx_us)
+                else if (ktime_lt(pkt_dev->next_tx, best->next_tx))
                         best = pkt_dev;
         }
         if_unlock(t);
@@ -3343,16 +3339,17 @@ static void pktgen_rem_thread(struct pktgen_thread *t)
 
 static void idle(struct pktgen_dev *pkt_dev)
 {
-        u64 idle_start = getCurUs();
+        ktime_t idle_start = ktime_now();
 
         if (need_resched())
                 schedule();
         else
                 cpu_relax();
 
-        pkt_dev->idle_acc += getCurUs() - idle_start;
+        pkt_dev->idle_acc += ktime_to_ns(ktime_sub(ktime_now(), idle_start));
 }
 
+
 static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 {
         struct net_device *odev = pkt_dev->odev;
@@ -3362,19 +3359,15 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
         u16 queue_map;
         int ret;
 
-        if (pkt_dev->delay_us || pkt_dev->delay_ns) {
-                u64 now;
-
-                now = getCurUs();
-                if (now < pkt_dev->next_tx_us)
-                        spin(pkt_dev, pkt_dev->next_tx_us);
+        if (pkt_dev->delay) {
+                if (ktime_lt(ktime_now(), pkt_dev->next_tx))
+                        spin(pkt_dev, pkt_dev->next_tx);
 
                 /* This is max DELAY, this has special meaning of
                  * "never transmit"
                  */
-                if (pkt_dev->delay_us == 0x7FFFFFFF) {
-                        pkt_dev->next_tx_us = getCurUs() + pkt_dev->delay_us;
-                        pkt_dev->next_tx_ns = pkt_dev->delay_ns;
+                if (pkt_dev->delay == ULLONG_MAX) {
+                        pkt_dev->next_tx = ktime_add_ns(ktime_now(), ULONG_MAX);
                         return;
                 }
         }
@@ -3450,32 +3443,24 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
                         pkt_dev->last_ok = 0;
                 }
 
-                if (pkt_dev->delay_us || pkt_dev->delay_ns) {
-                        pkt_dev->next_tx_us = getCurUs();
-                        pkt_dev->next_tx_ns = 0;
-
-                        pkt_dev->next_tx_us += pkt_dev->delay_us;
-                        pkt_dev->next_tx_ns += pkt_dev->delay_ns;
-
-                        if (pkt_dev->next_tx_ns > 1000) {
-                                pkt_dev->next_tx_us++;
-                                pkt_dev->next_tx_ns -= 1000;
-                        }
-                }
+                if (pkt_dev->delay)
+                        pkt_dev->next_tx = ktime_add_ns(ktime_now(),
+                                                        pkt_dev->delay);
         }
         __netif_tx_unlock_bh(txq);
 
         /* If pkt_dev->count is zero, then run forever */
         if ((pkt_dev->count != 0) && (pkt_dev->sofar >= pkt_dev->count)) {
                 if (atomic_read(&(pkt_dev->skb->users)) != 1) {
-                        u64 idle_start = getCurUs();
+                        ktime_t idle_start = ktime_now();
                         while (atomic_read(&(pkt_dev->skb->users)) != 1) {
                                 if (signal_pending(current)) {
                                         break;
                                 }
                                 schedule();
                         }
-                        pkt_dev->idle_acc += getCurUs() - idle_start;
+                        pkt_dev->idle_acc += ktime_to_ns(ktime_sub(ktime_now(),
+                                                                   idle_start));
                 }
 
                 /* Done with this */
@@ -3634,8 +3619,7 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname)
         pkt_dev->max_pkt_size = ETH_ZLEN;
         pkt_dev->nfrags = 0;
         pkt_dev->clone_skb = pg_clone_skb_d;
-        pkt_dev->delay_us = pg_delay_d / 1000;
-        pkt_dev->delay_ns = pg_delay_d % 1000;
+        pkt_dev->delay = pg_delay_d;
         pkt_dev->count = pg_count_d;
         pkt_dev->sofar = 0;
         pkt_dev->udp_src_min = 9;       /* sink port */