When frames are sent over the air, the device always applies the data
rates in descending order. The driver assumed Minstrel also provided
rate in descending order.
However, in some cases, Minstrel can a choose a fallback rate greater
than the primary rate. In this case, the two rates was inverted, the
device try highest rate first and we get many retries.
Since the device always applies rates in descending order, the
workaround is to drop the rate when it higher than its predecessor in
the rate list. Thus [ 4, 5, 3 ] becomes [ 4, 3 ].
This patch has been tested in isolated room with a series of
attenuators. Here are the Minstrel statistics with 80dBm of attenuation:
Without the fix:
best ____________rate__________ ____statistics___ _____last____ ______sum-of________
mode guard # rate [name idx airtime max_tp] [avg(tp) avg(prob)] [retry|suc|att] [#success | #attempts]
HT20 LGI 1 S MCS0 0 1477 5.6 5.2 82.7 3 0 0 3 4
HT20 LGI 1 MCS1 1 738 10.6 0.0 0.0 0 0 0 0 1
HT20 LGI 1 D MCS2 2 492 14.9 13.5 81.5 5 0 0 5 9
HT20 LGI 1 C MCS3 3 369 18.8 17.6 84.3 5 0 0 76 96
HT20 LGI 1 A P MCS4 4 246 25.4 22.4 79.5 5 0 0 11268 14026
HT20 LGI 1 B S MCS5 5 185 30.7 19.7 57.7 5 8 9 3918 9793
HT20 LGI 1 MCS6 6 164 33.0 0.0 0.0 5 0 0 6 102
HT20 LGI 1 MCS7 7 148 35.1 0.0 0.0 0 0 0 0 44
With the fix:
best ____________rate__________ ____statistics___ _____last____ ______sum-of________
mode guard # rate [name idx airtime max_tp] [avg(tp) avg(prob)] [retry|suc|att] [#success | #attempts]
HT20 LGI 1 S MCS0 0 1477 5.6 1.8 28.6 1 0 0 1 5
HT20 LGI 1 DP MCS1 1 738 10.6 9.7 82.6 4 0 0 14 34
HT20 LGI 1 MCS2 2 492 14.9 9.2 55.4 5 0 0 52 77
HT20 LGI 1 B S MCS3 3 369 18.8 15.6 74.9 5 1 1 417 554
HT20 LGI 1 A MCS4 4 246 25.4 16.7 59.2 5 1 1 13812 17951
HT20 LGI 1 C S MCS5 5 185 30.7 14.0 41.0 5 1 5 57 640
HT20 LGI 1 MCS6 6 164 33.0 0.0 0.0 0 0 1 0 48
HT20 LGI 1 S MCS7 7 148 35.1 0.0 0.0 0 0 0 0 36
We can notice the device try now to send with lower rates (and high
success rates). At the end, we measured 20-25% better throughput with
this patch.
Fixes: 9bca45f3d692 ("staging: wfx: allow to send 802.11 frames")
Tested-by: Olivier Souloumiac <olivier.souloumiac@silabs.com>
Tested-by: Alexandr Suslenko <suslenko.o@ajax.systems>
Reported-by: Alexandr Suslenko <suslenko.o@ajax.systems>
Co-developed-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Signed-off-by: Felipe Negrelli Wolter <felipe.negrelliwolter@silabs.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20231004123039.157112-1-jerome.pouiller@silabs.com
With some conditions, the device is able to send/receive frames during
scan operation. So, it is possible to use it implement the "remain on
channel" feature. We just ask for a passive scan (without sending any
probe request) on one channel.
This architecture allows to leverage some interesting features:
- if the device is AP, the device switches channel just after the next
beacon and the beacons are stopped during the off-channel interval.
- if the device is connected, it advertises it is asleep before to
switch channel (so the AP should stop to try to send data)
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20231004172843.195332-9-jerome.pouiller@silabs.com
Until now, all the traffic was blocked during scan operation. However, scan operation is going to be used to implement Remain On Channel (ROC). In this case, special frames (marked with IEEE80211_TX_CTL_TX_OFFCHAN) must be sent during the operation. These frames need to be sent on the virtual interface #2. Until now, this interface was only used by the device for internal purpose. But since API 3.9, it can be used to send data during scan operation (we hijack the scan process to implement ROC). Thus, we need to change a bit the way we match the frames with the interface. Fortunately, the frames received during the scan are marked with the correct interface number. So there is no change to do on this part. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-8-jerome.pouiller@silabs.com
Currently, one scan_lock is associated to each vif. However, concurrent scan on vifs is explicitly prohibited by the device. Currently, scan_lock is associated with a vif but it is always locked with conf_mutex (there is a case where conf_mutex is not associated to scan_lock but scan_lock is tested on all interfaces). So concurrent scan on vifs cannot happen. So, this patch relocate scan_lock to the device and simplify the code. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-7-jerome.pouiller@silabs.com
The device ignore the rx filters during the scan operation. wfx_configure_filter() acquires scan_lock to reflect this restriction. However, it is not really necessary since mac80211 don't try to configure Rx filters during scan. However, the things are changing. The scan operation is going to be used to implement remain-on-channel. In this case, wfx_configure_filter() can be called during the scan. Currently, this scenario generate a delay that end with a timeout in the upper layers. For the final user, some scenario of the EasyConnect specification end with a failure. So, avoid acquiring the scan_lock and just return. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-6-jerome.pouiller@silabs.com
Like hof_scan(), hif_scan_uniq() invoke HIF_SCAN. However, it only allows to probe one channel and disable probe requests. It works very well to implement Remain-On-Channel. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-5-jerome.pouiller@silabs.com
There is no real reasons to keep these function in the header file. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-4-jerome.pouiller@silabs.com
wfx_rate_mask_to_hw() is only used in hif_tx.c. So relocate it into hif_tx.c and mark it static. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-3-jerome.pouiller@silabs.com
The WF200 allow to start two network interfaces (one AP, one station) on two different channels. Since magic does not exist, it only works if the station interface enables power save. Thus, the driver detects this case and enforce power save as necessary. This patch fixes the case where the AP interface is stopped and it is no more necessary to enforce power saving on the station interface. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20231004172843.195332-2-jerome.pouiller@silabs.com
Use the helper function devm_kmemdup() rather than duplicating its implementation, which helps to enhance code readability. Signed-off-by: Li Zetao <lizetao1@huawei.com> Reviewed-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20230810114939.2104013-1-lizetao1@huawei.com