The first 9 patches of this set are unchanged from the RFC I sent more than a week ago. The 2 last patches are leftover minor cleanups, which I found laying around from last years cleaning job. David Laight was the only one commenting on the RFC, and I have interpreted his comment as a wish for further work on the usbnet framework, and not a request for any changes to this patch set. Hence this submission of without changes to patch 1-9, which I described like this for the RFC: "I have got quite a few reports from frustrated users of OpenWRT hosts trying to use some powerful LTE modem, but not achieving full speed. This is typically caused by a combination of big buffers and little memory, giving in allocation errors and bad performance as a result. This series is an attempt to let users adjust the size of these buffers without having to rebuild the driver. Patches 1 - 4 are mostly rearranging existing code, in preparing for the dynamic buffer size changes. Patch 5 adds userspace control (ab)using the ethtool coalescing API. This isn't a perfect match, which is the main reason why I post this series as a RFC. Patch 6 is an unrelated framing optimization, reducing the overhead quite a bit and allowing for better use of smaller buffers. Patch 7 changes the way we calculate frame padding cutoff. The problem with big buffers is made much worse by the current padding strategy where zero padding often can account for more than 90% of the frames. Patch 8 add some counters giving some insight into how well the NCM/MBIM protocol works, supporting further tuning. Patch 9 reduce the initial maximum buffer size from 32kB to 16kB in an attempt to make the default better suit all. It is still possible to tune this up again to the old fixed max, using the new tuning knobs. I must admit that I had higher hopes for this series before I tested it on my own modems. One really unexpected result was that one of the MBIM modems accepted the new rx buffer size we set, but happily continued sending buffers of the same size as before. Needless to say: This did not work very well... So don't really expect to be able to use any values with any given device. Firmware implementations are still... I don't think I have words suitable for a public mailing list. But I am hoping this will help the many users who have had success rebuilding the driver with lower fixed limits. Please test and/or comment!" And a short description of the 2 new patches since the RFC: Patch 10 is a follow-up to a comment Joe Perches made in November 2013. I don't always forget :-) Patch 11 removes the redundant "connected" driver state, and the associated .check_connect callbacks. Bjørn Mork (11): net: cdc_ncm: split out rx_max/tx_max update of setup net: cdc_ncm: factor out one-time device initialization net: cdc_ncm: split .bind device initialization net: cdc_ncm: support rx_max/tx_max updates when running net: cdc_ncm: use ethtool to tune coalescing settings net: cdc_ncm: use true max dgram count for header estimates net: cdc_ncm: set reasonable padding limits net: cdc_ncm/cdc_mbim: adding NCM protocol statiscics net: cdc_ncm: use sane defaults for rx/tx buffers net: cdc_ncm: fix argument alignment net: cdc_ncm: remove redundant "disconnected" flag drivers/net/usb/cdc_mbim.c | 6 + drivers/net/usb/cdc_ncm.c | 576 ++++++++++++++++++++++++++++----------- drivers/net/usb/huawei_cdc_ncm.c | 13 - include/linux/usb/cdc_ncm.h | 33 ++- 4 files changed, 442 insertions(+), 186 deletions(-) -- 2.0.0.rc2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
