diff mbox series

examples/l3fwd: remove useless reloads in FIB main loop

Message ID 20210705170546.1002806-1-conor.walsh@intel.com (mailing list archive)
State Accepted, archived
Delegated to: David Marchand
Headers show
Series examples/l3fwd: remove useless reloads in FIB main loop | expand

Checks

Context Check Description
ci/iol-abi-testing success Testing PASS
ci/iol-mellanox-Functional fail Functional Testing issues
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-testing fail Testing issues
ci/iol-intel-Functional success Functional Testing PASS
ci/github-robot success github build: passed
ci/checkpatch success coding style OK

Commit Message

Conor Walsh July 5, 2021, 5:05 p.m. UTC
This patch aligns the l3fwd FIB code with the changes made to LPM in
commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM
main loop").
This change ensures the compiler knows that the lcore config variables
are constant values and the compiler will then optimize the code
accordingly.

Signed-off-by: Conor Walsh <conor.walsh@intel.com>
---
 examples/l3fwd/l3fwd_fib.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Comments

Ananyev, Konstantin July 5, 2021, 5:32 p.m. UTC | #1
> 
> This patch aligns the l3fwd FIB code with the changes made to LPM in
> commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM
> main loop").
> This change ensures the compiler knows that the lcore config variables
> are constant values and the compiler will then optimize the code
> accordingly.
> 
> Signed-off-by: Conor Walsh <conor.walsh@intel.com>
> ---
>  examples/l3fwd/l3fwd_fib.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/examples/l3fwd/l3fwd_fib.c b/examples/l3fwd/l3fwd_fib.c
> index 1787229942..d083ddfdd5 100644
> --- a/examples/l3fwd/l3fwd_fib.c
> +++ b/examples/l3fwd/l3fwd_fib.c
> @@ -182,14 +182,16 @@ fib_main_loop(__rte_unused void *dummy)
>  	lcore_id = rte_lcore_id();
>  	qconf = &lcore_conf[lcore_id];
> 
> -	if (qconf->n_rx_queue == 0) {
> +	const uint16_t n_rx_q = qconf->n_rx_queue;
> +	const uint16_t n_tx_p = qconf->n_tx_port;
> +	if (n_rx_q == 0) {
>  		RTE_LOG(INFO, L3FWD, "lcore %u has nothing to do\n", lcore_id);
>  		return 0;
>  	}
> 
>  	RTE_LOG(INFO, L3FWD, "entering main loop on lcore %u\n", lcore_id);
> 
> -	for (i = 0; i < qconf->n_rx_queue; i++) {
> +	for (i = 0; i < n_rx_q; i++) {
> 
>  		portid = qconf->rx_queue_list[i].port_id;
>  		queueid = qconf->rx_queue_list[i].queue_id;
> @@ -207,7 +209,7 @@ fib_main_loop(__rte_unused void *dummy)
>  		diff_tsc = cur_tsc - prev_tsc;
>  		if (unlikely(diff_tsc > drain_tsc)) {
> 
> -			for (i = 0; i < qconf->n_tx_port; ++i) {
> +			for (i = 0; i < n_tx_p; ++i) {
>  				portid = qconf->tx_port_id[i];
>  				if (qconf->tx_mbufs[portid].len == 0)
>  					continue;
> @@ -221,7 +223,7 @@ fib_main_loop(__rte_unused void *dummy)
>  		}
> 
>  		/* Read packet from RX queues. */
> -		for (i = 0; i < qconf->n_rx_queue; ++i) {
> +		for (i = 0; i < n_rx_q; ++i) {
>  			portid = qconf->rx_queue_list[i].port_id;
>  			queueid = qconf->rx_queue_list[i].queue_id;
>  			nb_rx = rte_eth_rx_burst(portid, queueid, pkts_burst,
> --

Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

> 2.25.1
Ruifeng Wang July 6, 2021, 1:38 a.m. UTC | #2
> -----Original Message-----
> From: Conor Walsh <conor.walsh@intel.com>
> Sent: Tuesday, July 6, 2021 1:06 AM
> To: konstantin.ananyev@intel.com; vladimir.medvedkin@intel.com; Ruifeng
> Wang <Ruifeng.Wang@arm.com>; jerinj@marvell.com
> Cc: dev@dpdk.org; paulis.gributs@intel.com; Conor Walsh
> <conor.walsh@intel.com>
> Subject: [PATCH] examples/l3fwd: remove useless reloads in FIB main loop
> 
> This patch aligns the l3fwd FIB code with the changes made to LPM in commit
> 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM main loop").
> This change ensures the compiler knows that the lcore config variables are
> constant values and the compiler will then optimize the code accordingly.
> 
> Signed-off-by: Conor Walsh <conor.walsh@intel.com>
> ---
>  examples/l3fwd/l3fwd_fib.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
David Marchand July 6, 2021, 11:29 a.m. UTC | #3
On Mon, Jul 5, 2021 at 7:06 PM Conor Walsh <conor.walsh@intel.com> wrote:
>
> This patch aligns the l3fwd FIB code with the changes made to LPM in
> commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM
> main loop").
> This change ensures the compiler knows that the lcore config variables
> are constant values and the compiler will then optimize the code
> accordingly.

em can undergo the same change too.
Can you send a followup patch and I would take them both for rc1?

Thanks.

>
> Signed-off-by: Conor Walsh <conor.walsh@intel.com>
Conor Walsh July 6, 2021, 11:55 a.m. UTC | #4
> > This patch aligns the l3fwd FIB code with the changes made to LPM in
> > commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM
> > main loop").
> > This change ensures the compiler knows that the lcore config variables
> > are constant values and the compiler will then optimize the code
> > accordingly.
> 
> em can undergo the same change too.
> Can you send a followup patch and I would take them both for rc1?

Thanks! I will send a patch for em now
/Conor.

> 
> Thanks.
> 
> >
> > Signed-off-by: Conor Walsh <conor.walsh@intel.com>
> 
> --
> David Marchand
David Marchand July 7, 2021, 9:57 a.m. UTC | #5
On Mon, Jul 5, 2021 at 7:06 PM Conor Walsh <conor.walsh@intel.com> wrote:
>
> This patch aligns the l3fwd FIB code with the changes made to LPM in
> commit 74fb854a3de6 ("examples/l3fwd: remove useless reloads in LPM
> main loop").
> This change ensures the compiler knows that the lcore config variables
> are constant values and the compiler will then optimize the code
> accordingly.
>
> Signed-off-by: Conor Walsh <conor.walsh@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>

Applied, thanks.
diff mbox series

Patch

diff --git a/examples/l3fwd/l3fwd_fib.c b/examples/l3fwd/l3fwd_fib.c
index 1787229942..d083ddfdd5 100644
--- a/examples/l3fwd/l3fwd_fib.c
+++ b/examples/l3fwd/l3fwd_fib.c
@@ -182,14 +182,16 @@  fib_main_loop(__rte_unused void *dummy)
 	lcore_id = rte_lcore_id();
 	qconf = &lcore_conf[lcore_id];
 
-	if (qconf->n_rx_queue == 0) {
+	const uint16_t n_rx_q = qconf->n_rx_queue;
+	const uint16_t n_tx_p = qconf->n_tx_port;
+	if (n_rx_q == 0) {
 		RTE_LOG(INFO, L3FWD, "lcore %u has nothing to do\n", lcore_id);
 		return 0;
 	}
 
 	RTE_LOG(INFO, L3FWD, "entering main loop on lcore %u\n", lcore_id);
 
-	for (i = 0; i < qconf->n_rx_queue; i++) {
+	for (i = 0; i < n_rx_q; i++) {
 
 		portid = qconf->rx_queue_list[i].port_id;
 		queueid = qconf->rx_queue_list[i].queue_id;
@@ -207,7 +209,7 @@  fib_main_loop(__rte_unused void *dummy)
 		diff_tsc = cur_tsc - prev_tsc;
 		if (unlikely(diff_tsc > drain_tsc)) {
 
-			for (i = 0; i < qconf->n_tx_port; ++i) {
+			for (i = 0; i < n_tx_p; ++i) {
 				portid = qconf->tx_port_id[i];
 				if (qconf->tx_mbufs[portid].len == 0)
 					continue;
@@ -221,7 +223,7 @@  fib_main_loop(__rte_unused void *dummy)
 		}
 
 		/* Read packet from RX queues. */
-		for (i = 0; i < qconf->n_rx_queue; ++i) {
+		for (i = 0; i < n_rx_q; ++i) {
 			portid = qconf->rx_queue_list[i].port_id;
 			queueid = qconf->rx_queue_list[i].queue_id;
 			nb_rx = rte_eth_rx_burst(portid, queueid, pkts_burst,