| Message ID | 20200205191043.21913-1-linus.luessing@c0d3.blue (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ath10k: increase rx buffer size to 2048 | expand |
On Wednesday, 5 February 2020 20:10:43 CEST Linus Lüssing wrote: > From: Linus Lüssing <ll@simonwunderlich.de> > > Before, only frames with a maximum size of 1528 bytes could be > transmitted between two 802.11s nodes. > > For batman-adv for instance, which adds its own header to each frame, > we typically need an MTU of at least 1532 bytes to be able to transmit > without fragmentation. > > This patch now increases the maxmimum frame size from 1528 to 1656 > bytes. [...] @Kalle, I saw that this patch was marked as deferred [1] but I couldn't find any mail why it was done so. It seems like this currently creates real world problems - so would be nice if you could explain shortly what is currently blocking its acceptance. Kind regards, Sven [1] https://patchwork.kernel.org/patch/11367055/
On Wednesday, 1 April 2020 09:00:49 CEST Sven Eckelmann wrote: > On Wednesday, 5 February 2020 20:10:43 CEST Linus Lüssing wrote: > > From: Linus Lüssing <ll@simonwunderlich.de> > > > > Before, only frames with a maximum size of 1528 bytes could be > > transmitted between two 802.11s nodes. > > > > For batman-adv for instance, which adds its own header to each frame, > > we typically need an MTU of at least 1532 bytes to be able to transmit > > without fragmentation. > > > > This patch now increases the maxmimum frame size from 1528 to 1656 > > bytes. > [...] > > @Kalle, I saw that this patch was marked as deferred [1] but I couldn't find > any mail why it was done so. It seems like this currently creates real world > problems - so would be nice if you could explain shortly what is currently > blocking its acceptance. Ping? Kind regards, Sven > [1] https://patchwork.kernel.org/patch/11367055/
Sven Eckelmann <sven@narfation.org> writes: > On Wednesday, 1 April 2020 09:00:49 CEST Sven Eckelmann wrote: >> On Wednesday, 5 February 2020 20:10:43 CEST Linus Lüssing wrote: >> > From: Linus Lüssing <ll@simonwunderlich.de> >> > >> > Before, only frames with a maximum size of 1528 bytes could be >> > transmitted between two 802.11s nodes. >> > >> > For batman-adv for instance, which adds its own header to each frame, >> > we typically need an MTU of at least 1532 bytes to be able to transmit >> > without fragmentation. >> > >> > This patch now increases the maxmimum frame size from 1528 to 1656 >> > bytes. >> [...] >> >> @Kalle, I saw that this patch was marked as deferred [1] but I couldn't find >> any mail why it was done so. It seems like this currently creates real world >> problems - so would be nice if you could explain shortly what is currently >> blocking its acceptance. > > Ping? Sorry for the delay, my plan was to first write some documentation about different hardware families but haven't managed to do that yet. My problem with this patch is that I don't know what hardware and firmware versions were tested, so it needs analysis before I feel safe to apply it. The ath10k hardware families are very different that even if a patch works perfectly on one ath10k hardware it could still break badly on another one. What makes me faster to apply ath10k patches is to have comprehensive analysis in the commit log. This shows me the patch author has considered about all hardware families, not just the one he is testing on, and that I don't need to do the analysis myself.
On Tue, Apr 28, 2020 at 5:06 AM Kalle Valo <kvalo@codeaurora.org> wrote: > > Sven Eckelmann <sven@narfation.org> writes: > > > On Wednesday, 1 April 2020 09:00:49 CEST Sven Eckelmann wrote: > >> On Wednesday, 5 February 2020 20:10:43 CEST Linus Lüssing wrote: > >> > From: Linus Lüssing <ll@simonwunderlich.de> > >> > > >> > Before, only frames with a maximum size of 1528 bytes could be > >> > transmitted between two 802.11s nodes. > >> > > >> > For batman-adv for instance, which adds its own header to each frame, > >> > we typically need an MTU of at least 1532 bytes to be able to transmit > >> > without fragmentation. > >> > > >> > This patch now increases the maxmimum frame size from 1528 to 1656 > >> > bytes. > >> [...] > >> > >> @Kalle, I saw that this patch was marked as deferred [1] but I couldn't find > >> any mail why it was done so. It seems like this currently creates real world > >> problems - so would be nice if you could explain shortly what is currently > >> blocking its acceptance. > > > > Ping? > > Sorry for the delay, my plan was to first write some documentation about > different hardware families but haven't managed to do that yet. > > My problem with this patch is that I don't know what hardware and > firmware versions were tested, so it needs analysis before I feel safe > to apply it. The ath10k hardware families are very different that even > if a patch works perfectly on one ath10k hardware it could still break > badly on another one. > > What makes me faster to apply ath10k patches is to have comprehensive > analysis in the commit log. This shows me the patch author has > considered about all hardware families, not just the one he is testing > on, and that I don't need to do the analysis myself. I have been struggling to get the ath10k to sing and dance using various variants of the firmware, on this bug over here: https://forum.openwrt.org/t/aql-and-the-ath10k-is-lovely/ The puzzling thing is the loss of bidirectional throughput at codel target 20, and getting WAY more (but less than I expected) at codel target 5. This doesn't quite have bearing the size of the rx ring, except that in my experiments the rx ring is rather small!! and yet I get way more performance out of it.... (still, as you'll see from the bug, it's WAY better than it used to be) is NAPI in this driver? I'm afraid to look. > -- > https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On 04/28/2020 05:01 AM, Kalle Valo wrote: > Sven Eckelmann <sven@narfation.org> writes: > >> On Wednesday, 1 April 2020 09:00:49 CEST Sven Eckelmann wrote: >>> On Wednesday, 5 February 2020 20:10:43 CEST Linus Lüssing wrote: >>>> From: Linus Lüssing <ll@simonwunderlich.de> >>>> >>>> Before, only frames with a maximum size of 1528 bytes could be >>>> transmitted between two 802.11s nodes. >>>> >>>> For batman-adv for instance, which adds its own header to each frame, >>>> we typically need an MTU of at least 1532 bytes to be able to transmit >>>> without fragmentation. >>>> >>>> This patch now increases the maxmimum frame size from 1528 to 1656 >>>> bytes. >>> [...] >>> >>> @Kalle, I saw that this patch was marked as deferred [1] but I couldn't find >>> any mail why it was done so. It seems like this currently creates real world >>> problems - so would be nice if you could explain shortly what is currently >>> blocking its acceptance. >> >> Ping? > > Sorry for the delay, my plan was to first write some documentation about > different hardware families but haven't managed to do that yet. > > My problem with this patch is that I don't know what hardware and > firmware versions were tested, so it needs analysis before I feel safe > to apply it. The ath10k hardware families are very different that even > if a patch works perfectly on one ath10k hardware it could still break > badly on another one. > > What makes me faster to apply ath10k patches is to have comprehensive > analysis in the commit log. This shows me the patch author has > considered about all hardware families, not just the one he is testing > on, and that I don't need to do the analysis myself. It has been in ath10k-ct for a while, and that has some fairly wide coverage in OpenWrt, so likely if there were problems we would have seen it already. I did not make any specific changes to firmware to support this, so upstream firmware should behave similarly. Seems like upstream ath10k could really benefit from having some test beds so you can actually test code on different chips and have confidence in your changes! Thanks, Ben
diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h index 4a12564fc30e..6a2b5e10e568 100644 --- a/drivers/net/wireless/ath/ath10k/htt.h +++ b/drivers/net/wireless/ath/ath10k/htt.h @@ -2220,7 +2220,7 @@ struct htt_rx_chan_info { * Should be: sizeof(struct htt_host_rx_desc) + max rx MSDU size, * rounded up to a cache line size. */ -#define HTT_RX_BUF_SIZE 1920 +#define HTT_RX_BUF_SIZE 2048 #define HTT_RX_MSDU_SIZE (HTT_RX_BUF_SIZE - (int)sizeof(struct htt_rx_desc)) /* Refill a bunch of RX buffers for each refill round so that FW/HW can handle