diff mbox

[1/2] pktgen: increasing transmission granularity

Message ID 4C064533.6070709@gmail.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Daniel Turull June 2, 2010, 11:49 a.m. UTC 
This patch increases the granularity of the rate generated by pktgen.
The previous version of pktgen uses micro seconds (udelay) resolution when it 
was delayed causing gaps in the rates. It is changed to nanosecond (ndelay).
Now any rate is possible.

Also it allows to set, the desired rate in Mb/s or packets per second.

The documentation has been updated.

Signed-off-by: Daniel Turull <daniel.turull@gmail.com>

---

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

David Miller June 9, 2010, 8:50 p.m. UTC | #1 
From: Daniel Turull <daniel.turull@gmail.com>
Date: Wed, 02 Jun 2010 13:49:07 +0200

> This patch increases the granularity of the rate generated by pktgen.
> The previous version of pktgen uses micro seconds (udelay) resolution when it 
> was delayed causing gaps in the rates. It is changed to nanosecond (ndelay).
> Now any rate is possible.
> 
> Also it allows to set, the desired rate in Mb/s or packets per second.
> 
> The documentation has been updated.
> 
> Signed-off-by: Daniel Turull <daniel.turull@gmail.com>

I like this, however although most of this is adding a new
feature, this part:

> @@ -2170,7 +2204,7 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
>  	end_time = ktime_now();
>  
>  	pkt_dev->idle_acc += ktime_to_ns(ktime_sub(end_time, start_time));
> -	pkt_dev->next_tx = ktime_add_ns(end_time, pkt_dev->delay);
> +	pkt_dev->next_tx = ktime_add_ns(spin_until, pkt_dev->delay);
>  }
>  
>  static inline void set_pkt_overhead(struct pktgen_dev *pkt_dev)

Is a bug fix, since it makes sure the inter-packet interval is
accurate.

Can you please submit this part seperately, so I can apply it to
net-2.6   Then you can submit the nanosecond feature parts
relative to this, which I'll apply to net-next-2.6

Thanks!
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/Documentation/networking/pktgen.txt b/Documentation/networking/pktgen.txt
index 61bb645..ac0e4ff 100644
--- a/Documentation/networking/pktgen.txt
+++ b/Documentation/networking/pktgen.txt
@@ -78,6 +78,9 @@  Examples:
 
  pgset "delay 5000"      adds delay to hard_start_xmit(). nanoseconds
 
+ pgset "rate 300M"       set rate to 300 Mb/s
+ pgset "ratep 1000000"   set rate to 1Mpps
+
  pgset "dst 10.0.0.1"    sets IP destination address
                          (BEWARE! This generator is very aggressive!)
 
@@ -200,6 +203,9 @@  debug
 frags
 delay
 
+rate
+ratep
+
 src_mac_count
 dst_mac_count
 
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 2ad68da..6428653 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -169,7 +169,7 @@ 
 #include <asm/dma.h>
 #include <asm/div64.h>		/* do_div */
 
-#define VERSION 	"2.73"
+#define VERSION	"2.74"
 #define IP_NAME_SZ 32
 #define MAX_MPLS_LABELS 16 /* This is the max label stack depth */
 #define MPLS_STACK_BOTTOM htonl(0x00000100)
@@ -980,6 +980,40 @@  static ssize_t pktgen_if_write(struct file *file,
 			(unsigned long long) pkt_dev->delay);
 		return count;
 	}
+	if (!strcmp(name, "rate")) {
+		len = num_arg(&user_buffer[i], 10, &value);
+		if (len < 0)
+			return len;
+
+		i += len;
+		if (!value)
+			return len;
+		pkt_dev->delay = pkt_dev->min_pkt_size*8*NSEC_PER_USEC/value;
+		if (debug)
+			printk(KERN_INFO
+				 "pktgen: Delay set at: %llu ns\n",
+					pkt_dev->delay);
+
+		sprintf(pg_result, "OK: rate=%lu", value);
+		return count;
+	}
+	if (!strcmp(name, "ratep")) {
+		len = num_arg(&user_buffer[i], 10, &value);
+		if (len < 0)
+			return len;
+
+		i += len;
+		if (!value)
+			return len;
+		pkt_dev->delay = NSEC_PER_SEC/value;
+		if (debug)
+			printk(KERN_INFO
+				 "pktgen: Delay set at: %llu ns\n",
+					pkt_dev->delay);
+
+		sprintf(pg_result, "OK: rate=%lu", value);
+		return count;
+	}
 	if (!strcmp(name, "udp_src_min")) {
 		len = num_arg(&user_buffer[i], 10, &value);
 		if (len < 0)
@@ -2142,15 +2176,15 @@  static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
 	hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 	hrtimer_set_expires(&t.timer, spin_until);
 
-	remaining = ktime_to_us(hrtimer_expires_remaining(&t.timer));
+	remaining = ktime_to_ns(hrtimer_expires_remaining(&t.timer));
 	if (remaining <= 0) {
 		pkt_dev->next_tx = ktime_add_ns(spin_until, pkt_dev->delay);
 		return;
 	}
 
 	start_time = ktime_now();
-	if (remaining < 100)
-		udelay(remaining); 	/* really small just spin */
+	if (remaining < 100000)
+		ndelay(remaining);	/* really small just spin */
 	else {
 		/* see do_nanosleep */
 		hrtimer_init_sleeper(&t, current);
@@ -2170,7 +2204,7 @@  static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
 	end_time = ktime_now();
 
 	pkt_dev->idle_acc += ktime_to_ns(ktime_sub(end_time, start_time));
-	pkt_dev->next_tx = ktime_add_ns(end_time, pkt_dev->delay);
+	pkt_dev->next_tx = ktime_add_ns(spin_until, pkt_dev->delay);
 }
 
 static inline void set_pkt_overhead(struct pktgen_dev *pkt_dev)