Linux kernel stable tree (mirror) https://git.radix-linux.su/kernel/linux.git/atom?h=linux-4.16.y 2016-12-15T08:43:05+00:00 2016-12-15T08:43:05+00:00 Toke Høiland-Jørgensen toke@toke.dk 2016-12-05T11:27:37+00:00 urn:sha1:63fefa050477b0974ab34f650e21a7cfc3b02d96 This reworks the ath9k driver to schedule transmissions to connected stations in a way that enforces airtime fairness between them. It accomplishes this by measuring the time spent transmitting to or receiving from a station at TX and RX completion, and accounting this to a per-station, per-QoS level airtime deficit. Then, an FQ-CoDel based deficit scheduler is employed at packet dequeue time, to control which station gets the next transmission opportunity. Airtime fairness can significantly improve the efficiency of the network when station rates vary. The following throughput values are from a simple three-station test scenario, where two stations operate at the highest HT20 rate, and one station at the lowest, and the scheduler is employed at the access point: Before / After Fast station 1: 19.17 / 25.09 Mbps Fast station 2: 19.83 / 25.21 Mbps Slow station: 2.58 / 1.77 Mbps Total: 41.58 / 52.07 Mbps The benefit of airtime fairness goes up the more stations are present. In a 30-station test with one station artificially limited to 1 Mbps, we have seen aggregate throughput go from 2.14 to 17.76 Mbps. Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com> 2016-11-15T15:00:04+00:00 Toke Høiland-Jørgensen toke@toke.dk 2016-11-09T11:31:49+00:00 urn:sha1:50f08edf98096a68f01ff4566b605a25bf8e42ce This switches ath9k over to using the mac80211 intermediate software queueing mechanism for data packets. It removes the queueing inside the driver, except for the retry queue, and instead pulls from mac80211 when a packet is needed. The retry queue is used to store a packet that was pulled but can't be sent immediately. The old code path in ath_tx_start that would queue packets has been removed completely, as has the qlen limit tunables (since there's no longer a queue in the driver to limit). The mac80211 intermediate software queues offer significant latency reductions, and this patch allows ath9k to realise them. The exact gains from this varies with the test scenario, but in an access point scenario we have seen latency reductions ranging from 1/3 to as much as an order of magnitude. We also achieve slightly better aggregation. Median latency (ping) figures with this patch applied at the access point, with two high-rate stations and one low-rate station (HT20 5Ghz), running a Flent rtt_fair_var_up test with one TCP flow and one ping flow going to each station: Fast station Slow station Default pfifo_fast qdisc: 430.4 ms 638.7 ms fq_codel qdisc on iface: 35.5 ms 211.8 ms This patch set: 22.4 ms 38.2 ms Median aggregation sizes over the same test: Default pfifo_fast qdisc: 9.5 pkts 1.9 pkts fq_codel qdisc on iface: 11.2 pkts 1.9 pkts This patch set: 13.9 pkts 1.9 pkts This patch is based on Tim's original patch set, but reworked quite thoroughly. Cc: Tim Shepard <shep@alum.mit.edu> Cc: Felix Fietkau <nbd@nbd.name> Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com> 2015-07-21T13:56:41+00:00 Felix Fietkau nbd@openwrt.org 2015-07-02T11:40:29+00:00 urn:sha1:e60ac9c7a4c8776b2503892dfd01f1b4d651245d A long time ago, ath9k had issues during reset where the DMA engine would stay active and could potentially corrupt memory. To debug those issues, the driver would print warnings whenever they occur. Nowadays, these issues are gone and the primary cause of these messages is if the MAC is stuck during reset or busy processing a long transmission. This is fairly harmless, yet these messages continue to worry users. To reduce the number of bogus bug reports, turn these messages into debug messages and count their occurence in the "reset" debugfs file. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> 2014-12-15T00:10:09+00:00 Linus Torvalds torvalds@linux-foundation.org 2014-12-15T00:10:09+00:00 urn:sha1:e6b5be2be4e30037eb551e0ed09dd97bd00d85d3 Pull driver core update from Greg KH: "Here's the set of driver core patches for 3.19-rc1. They are dominated by the removal of the .owner field in platform drivers. They touch a lot of files, but they are "simple" changes, just removing a line in a structure. Other than that, a few minor driver core and debugfs changes. There are some ath9k patches coming in through this tree that have been acked by the wireless maintainers as they relied on the debugfs changes. Everything has been in linux-next for a while" * tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits) Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries" fs: debugfs: add forward declaration for struct device type firmware class: Deletion of an unnecessary check before the function call "vunmap" firmware loader: fix hung task warning dump devcoredump: provide a one-way disable function device: Add dev_<level>_once variants ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries ath: use seq_file api for ath9k debugfs files debugfs: add helper function to create device related seq_file drivers/base: cacheinfo: remove noisy error boot message Revert "core: platform: add warning if driver has no owner" drivers: base: support cpu cache information interface to userspace via sysfs drivers: base: add cpu_device_create to support per-cpu devices topology: replace custom attribute macros with standard DEVICE_ATTR* cpumask: factor out show_cpumap into separate helper function driver core: Fix unbalanced device reference in drivers_probe driver core: fix race with userland in device_add() sysfs/kernfs: make read requests on pre-alloc files use the buffer. sysfs/kernfs: allow attributes to request write buffer be pre-allocated. fs: sysfs: return EGBIG on write if offset is larger than file size ... 2014-11-27T03:38:37+00:00 Arend van Spriel arend@broadcom.com 2014-11-09T10:31:59+00:00 urn:sha1:631bee257bd506ad6622aac16dfeedce09034ade The debugfs files that are defined in debug.c which are read-only and using a simple_open as .open file operation have been modified to use the single_open seq_file API. This simplifies the read functions defining the file contents. Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 2014-10-27T18:16:18+00:00 Felix Fietkau nbd@openwrt.org 2014-10-25T15:19:30+00:00 urn:sha1:7b8aaead958e38b1eb8944c5f9c90ce066500268 When NF calibration fails, the radio often becomes deaf. The usual hardware hang checks do not detect this, so it's better to issue a reset when that happens. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> 2014-05-13T19:56:40+00:00 Oleksij Rempel linux@rempel-privat.de 2014-05-11T08:04:36+00:00 urn:sha1:b5a0c86a56e4494eab84b142ab5501eb62685150 and use it. This move need changes in both drivers. Signed-off-by: Oleksij Rempel <linux@rempel-privat.de> Signed-off-by: John W. Linville <linville@tuxdriver.com> 2014-02-12T20:36:04+00:00 Sujith Manoharan c_manoha@qca.qualcomm.com 2014-02-06T04:52:55+00:00 urn:sha1:9e495a2603334f9c8fcc6802300c22fc8a0eae02 There is no benefit in retaining the legacy rate control module in the driver codebase. It is known to be buggy and has less than optimal performance in real-world environments compared with minstrel. The only reason that it was kept when we made the switch to minstrel as default was that it showed higher throughput numbers in a clean/ideal environment. This is no longer the case and minstrel can push ath9k to the same throughput levels. In TCP, with 3-stream cards, more than 295 Mbps can be obtained in open air, with 2-stream cards, 210 Mbps is easily reached. To test performance issues, instead of using a broken rate control module, it is better to use the fixed-rate interface provided by mac80211 anyway. The ath9k RC has not received any bug fixes in years and is just bit-rotting away - this patch removes it. Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 2014-01-13T19:50:05+00:00 Sujith Manoharan c_manoha@qca.qualcomm.com 2014-01-13T08:25:11+00:00 urn:sha1:071aa9a8b2e724679ac2cf14f31b781a3783c377 Global Transmission Timeout interrupts are generated by the HW when transmission of a frame fails - this is done based on the threshold programmed in the AR_GTXTO register. Currently, even though the interrupt is enabled for all chips, it is not handled in the driver. This patch handles GTT events for AR9003 and above chips, checking if the MAC/BB has hung after successive GTT interrupts crosses a threshold (5). This can be enabled for the older chips in the AR9002 family once appropriate HW hang checks are implemented for them. Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> 2014-01-13T19:50:05+00:00 Sujith Manoharan c_manoha@qca.qualcomm.com 2014-01-13T01:59:30+00:00 urn:sha1:350e2dcb4647d144000db1505c94d586fcd57919 This would be useful when debugging RX performance issues. Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>