diff mbox series

[net-next,v3,2/2] tg3: Link queues to NAPIs

Message ID 20241005145717.302575-3-jdamato@fastly.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series tg3: Link IRQs, NAPIs, and queues | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 6 this patch: 6
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 16 this patch: 16
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 51 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 2 this patch: 2
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-10-06--15-00 (tests: 775)

Commit Message

Joe Damato Oct. 5, 2024, 2:57 p.m. UTC
Link queues to NAPIs using the netdev-genl API so this information is
queryable.

$ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
                         --dump queue-get --json='{"ifindex": 2}'

[{'id': 0, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
 {'id': 1, 'ifindex': 2, 'napi-id': 8195, 'type': 'rx'},
 {'id': 2, 'ifindex': 2, 'napi-id': 8196, 'type': 'rx'},
 {'id': 3, 'ifindex': 2, 'napi-id': 8197, 'type': 'rx'},
 {'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'}]

Signed-off-by: Joe Damato <jdamato@fastly.com>
---
 drivers/net/ethernet/broadcom/tg3.c | 37 +++++++++++++++++++++++++----
 1 file changed, 33 insertions(+), 4 deletions(-)

Comments

Michael Chan Oct. 7, 2024, 7:30 a.m. UTC | #1
On Sat, Oct 5, 2024 at 7:57 AM Joe Damato <jdamato@fastly.com> wrote:
>
> Link queues to NAPIs using the netdev-genl API so this information is
> queryable.
>
> $ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
>                          --dump queue-get --json='{"ifindex": 2}'
>
> [{'id': 0, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
>  {'id': 1, 'ifindex': 2, 'napi-id': 8195, 'type': 'rx'},
>  {'id': 2, 'ifindex': 2, 'napi-id': 8196, 'type': 'rx'},
>  {'id': 3, 'ifindex': 2, 'napi-id': 8197, 'type': 'rx'},
>  {'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'}]
>
> Signed-off-by: Joe Damato <jdamato@fastly.com>

>  static void tg3_napi_enable(struct tg3 *tp)
>  {
> +       int txq_idx = 0, rxq_idx = 0;
> +       struct tg3_napi *tnapi;
>         int i;
>
> -       for (i = 0; i < tp->irq_cnt; i++)
> -               napi_enable(&tp->napi[i].napi);
> +       for (i = 0; i < tp->irq_cnt; i++) {
> +               tnapi = &tp->napi[i];
> +               napi_enable(&tnapi->napi);
> +               if (tnapi->tx_buffers) {
> +                       netif_queue_set_napi(tp->dev, txq_idx,
> +                                            NETDEV_QUEUE_TYPE_TX,
> +                                            &tnapi->napi);
> +                       txq_idx++;
> +               } else if (tnapi->rx_rcb) {

Shouldn't this be "if" instead of "else if" ?  A napi can be for both
a TX ring and an RX ring in some cases.
Thanks.

> +                       netif_queue_set_napi(tp->dev, rxq_idx,
> +                                            NETDEV_QUEUE_TYPE_RX,
> +                                            &tnapi->napi);
> +                       rxq_idx++;
> +               }
> +       }
>  }
Joe Damato Oct. 7, 2024, 1:38 p.m. UTC | #2
On Mon, Oct 07, 2024 at 12:30:09AM -0700, Michael Chan wrote:
> On Sat, Oct 5, 2024 at 7:57 AM Joe Damato <jdamato@fastly.com> wrote:
> >
> > Link queues to NAPIs using the netdev-genl API so this information is
> > queryable.
> >
> > $ ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \
> >                          --dump queue-get --json='{"ifindex": 2}'
> >
> > [{'id': 0, 'ifindex': 2, 'napi-id': 8194, 'type': 'rx'},
> >  {'id': 1, 'ifindex': 2, 'napi-id': 8195, 'type': 'rx'},
> >  {'id': 2, 'ifindex': 2, 'napi-id': 8196, 'type': 'rx'},
> >  {'id': 3, 'ifindex': 2, 'napi-id': 8197, 'type': 'rx'},
> >  {'id': 0, 'ifindex': 2, 'napi-id': 8193, 'type': 'tx'}]
> >
> > Signed-off-by: Joe Damato <jdamato@fastly.com>
> 
> >  static void tg3_napi_enable(struct tg3 *tp)
> >  {
> > +       int txq_idx = 0, rxq_idx = 0;
> > +       struct tg3_napi *tnapi;
> >         int i;
> >
> > -       for (i = 0; i < tp->irq_cnt; i++)
> > -               napi_enable(&tp->napi[i].napi);
> > +       for (i = 0; i < tp->irq_cnt; i++) {
> > +               tnapi = &tp->napi[i];
> > +               napi_enable(&tnapi->napi);
> > +               if (tnapi->tx_buffers) {
> > +                       netif_queue_set_napi(tp->dev, txq_idx,
> > +                                            NETDEV_QUEUE_TYPE_TX,
> > +                                            &tnapi->napi);
> > +                       txq_idx++;
> > +               } else if (tnapi->rx_rcb) {
> 
> Shouldn't this be "if" instead of "else if" ?  A napi can be for both
> a TX ring and an RX ring in some cases.
> Thanks.

OK, but is this approach (with the running counters) acceptable for
rxq and txq numbering? If not, can you suggest an alternative?
Joe Damato Oct. 7, 2024, 2:23 p.m. UTC | #3
On Mon, Oct 07, 2024 at 12:30:09AM -0700, Michael Chan wrote:
> On Sat, Oct 5, 2024 at 7:57 AM Joe Damato <jdamato@fastly.com> wrote:
> > +               if (tnapi->tx_buffers) {
> > +                       netif_queue_set_napi(tp->dev, txq_idx,
> > +                                            NETDEV_QUEUE_TYPE_TX,
> > +                                            &tnapi->napi);
> > +                       txq_idx++;
> > +               } else if (tnapi->rx_rcb) {
> 
> Shouldn't this be "if" instead of "else if" ?  A napi can be for both
> a TX ring and an RX ring in some cases.
> Thanks.

BTW: tg3 set_channels doesn't seem to support combined queues;
combined_count is not even examined in set_channels. But maybe
the link queue can be a combined queue, I don't know.

Regardless, I'll still make the change you requested as there is
similar code in tg3_request_irq.

But what I really would like to get feedback on is the rxq and txq
indexing with the running counters, please. That was called out
explicitly in the cover letter.

Thanks.
Michael Chan Oct. 7, 2024, 10:39 p.m. UTC | #4
On Mon, Oct 7, 2024 at 7:23 AM Joe Damato <jdamato@fastly.com> wrote:
>
> On Mon, Oct 07, 2024 at 12:30:09AM -0700, Michael Chan wrote:
> > On Sat, Oct 5, 2024 at 7:57 AM Joe Damato <jdamato@fastly.com> wrote:
> > > +               if (tnapi->tx_buffers) {
> > > +                       netif_queue_set_napi(tp->dev, txq_idx,
> > > +                                            NETDEV_QUEUE_TYPE_TX,
> > > +                                            &tnapi->napi);
> > > +                       txq_idx++;
> > > +               } else if (tnapi->rx_rcb) {
> >
> > Shouldn't this be "if" instead of "else if" ?  A napi can be for both
> > a TX ring and an RX ring in some cases.
> > Thanks.
>
> BTW: tg3 set_channels doesn't seem to support combined queues;
> combined_count is not even examined in set_channels. But maybe
> the link queue can be a combined queue, I don't know.

tg3 is a little odd.  When there are more than 1 MSIX, TX starts from
vector 0 but RX starts at vector 1.  If there are more than 1 TX ring,
the 2nd TX ring is combined with the 1st RX ring and so on.

>
> Regardless, I'll still make the change you requested as there is
> similar code in tg3_request_irq.
>
> But what I really would like to get feedback on is the rxq and txq
> indexing with the running counters, please. That was called out
> explicitly in the cover letter.
>

It looks reasonable to me.  Thanks.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index 6564072b47ba..12172783b9b6 100644
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -7395,18 +7395,47 @@  static int tg3_poll(struct napi_struct *napi, int budget)
 
 static void tg3_napi_disable(struct tg3 *tp)
 {
+	int txq_idx = tp->txq_cnt - 1;
+	int rxq_idx = tp->rxq_cnt - 1;
+	struct tg3_napi *tnapi;
 	int i;
 
-	for (i = tp->irq_cnt - 1; i >= 0; i--)
-		napi_disable(&tp->napi[i].napi);
+	for (i = tp->irq_cnt - 1; i >= 0; i--) {
+		tnapi = &tp->napi[i];
+		if (tnapi->tx_buffers) {
+			netif_queue_set_napi(tp->dev, txq_idx,
+					     NETDEV_QUEUE_TYPE_TX, NULL);
+			txq_idx--;
+		} else if (tnapi->rx_rcb) {
+			netif_queue_set_napi(tp->dev, rxq_idx,
+					     NETDEV_QUEUE_TYPE_RX, NULL);
+			rxq_idx--;
+		}
+		napi_disable(&tnapi->napi);
+	}
 }
 
 static void tg3_napi_enable(struct tg3 *tp)
 {
+	int txq_idx = 0, rxq_idx = 0;
+	struct tg3_napi *tnapi;
 	int i;
 
-	for (i = 0; i < tp->irq_cnt; i++)
-		napi_enable(&tp->napi[i].napi);
+	for (i = 0; i < tp->irq_cnt; i++) {
+		tnapi = &tp->napi[i];
+		napi_enable(&tnapi->napi);
+		if (tnapi->tx_buffers) {
+			netif_queue_set_napi(tp->dev, txq_idx,
+					     NETDEV_QUEUE_TYPE_TX,
+					     &tnapi->napi);
+			txq_idx++;
+		} else if (tnapi->rx_rcb) {
+			netif_queue_set_napi(tp->dev, rxq_idx,
+					     NETDEV_QUEUE_TYPE_RX,
+					     &tnapi->napi);
+			rxq_idx++;
+		}
+	}
 }
 
 static void tg3_napi_init(struct tg3 *tp)