In terms of deeply grokking what increasing buffering to achieve high bandwidth on a testbench, vs what it can do to clobber latency in the real world at low bandwidths, I tend to point folk at: https://www.youtube.com/watch?v=Rb-UnHDw02o&t=25m40s where I got a whole bunch of hackers to stand up and act like packets in an aggregating FIFO wifi queue. This key section is only 8 minutes long, and I promise, y'all laugh at least 3 times at the demonstration. At the time, also, the ath10k was so overbuffered that on one test I could try to start 100 flows, and only get five. https://lwn.net/Articles/705884/ and on my slides: https://blog.linuxplumbersconf.org/2016/ocw//system/presentations/3963/original/linuxplumbers_wifi_latency-3Nov.pdf Wen Gong <wgong@xxxxxxxxxxxxxx> writes: > The max bundle size support by firmware is 32, change it from 8 to 32 > will help performance. This results in significant performance > improvement on RX path. > > Tested with QCA6174 SDIO with firmware > WLAN.RMH.4.4.1-00007-QCARMSWP-1. > > Signed-off-by: Wen Gong <wgong@xxxxxxxxxxxxxx> > --- > drivers/net/wireless/ath/ath10k/htc.h | 2 +- > drivers/net/wireless/ath/ath10k/sdio.c | 5 +++-- > drivers/net/wireless/ath/ath10k/sdio.h | 4 ++-- > 3 files changed, 6 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/wireless/ath/ath10k/htc.h b/drivers/net/wireless/ath/ath10k/htc.h > index f55d3ca..8c79b9e 100644 > --- a/drivers/net/wireless/ath/ath10k/htc.h > +++ b/drivers/net/wireless/ath/ath10k/htc.h > @@ -39,7 +39,7 @@ > * 4-byte aligned. > */ > > -#define HTC_HOST_MAX_MSG_PER_RX_BUNDLE 8 > +#define HTC_HOST_MAX_MSG_PER_RX_BUNDLE 32 > > enum ath10k_htc_tx_flags { > ATH10K_HTC_FLAG_NEED_CREDIT_UPDATE = 0x01, > diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c > index d9395f0..baa6051 100644 > --- a/drivers/net/wireless/ath/ath10k/sdio.c > +++ b/drivers/net/wireless/ath/ath10k/sdio.c > @@ -24,8 +24,8 @@ > #include "trace.h" > #include "sdio.h" > > -#define ATH10K_SDIO_DMA_BUF_SIZE (32 * 1024) > -#define ATH10K_SDIO_VSG_BUF_SIZE (32 * 1024) > +#define ATH10K_SDIO_DMA_BUF_SIZE (64 * 1024) > +#define ATH10K_SDIO_VSG_BUF_SIZE (64 * 1024) > > /* inlined helper functions */ > > @@ -501,6 +501,7 @@ static int ath10k_sdio_mbox_alloc_bundle(struct ath10k *ar, > int ret, i; > > *bndl_cnt = FIELD_GET(ATH10K_HTC_FLAG_BUNDLE_MASK, htc_hdr->flags); > + *bndl_cnt += (FIELD_GET(GENMASK(3, 2), htc_hdr->flags) << 4); > > if (*bndl_cnt > HTC_HOST_MAX_MSG_PER_RX_BUNDLE) { > ath10k_warn(ar, > diff --git a/drivers/net/wireless/ath/ath10k/sdio.h b/drivers/net/wireless/ath/ath10k/sdio.h > index 4896eca..3ca76c7 100644 > --- a/drivers/net/wireless/ath/ath10k/sdio.h > +++ b/drivers/net/wireless/ath/ath10k/sdio.h > @@ -89,10 +89,10 @@ > * to the maximum value (HTC_HOST_MAX_MSG_PER_RX_BUNDLE). > * > * in this case the driver must allocate > - * (HTC_HOST_MAX_MSG_PER_RX_BUNDLE * HTC_HOST_MAX_MSG_PER_RX_BUNDLE) skb's. > + * (HTC_HOST_MAX_MSG_PER_RX_BUNDLE * 2) skb's. > */ > #define ATH10K_SDIO_MAX_RX_MSGS \ > - (HTC_HOST_MAX_MSG_PER_RX_BUNDLE * HTC_HOST_MAX_MSG_PER_RX_BUNDLE) > + (HTC_HOST_MAX_MSG_PER_RX_BUNDLE * 2) > > #define ATH10K_FIFO_TIMEOUT_AND_CHIP_CONTROL 0x00000868u > #define ATH10K_FIFO_TIMEOUT_AND_CHIP_CONTROL_DISABLE_SLEEP_OFF 0xFFFEFFFF
