Re: [PATCH 02/31] staging: wfx: do not send CAB while scanning
From: Kari Argillander <hidden>
Date: 2021-09-10 16:31:07
Also in:
linux-wireless, lkml
On Fri, Sep 10, 2021 at 06:04:35PM +0200, Jerome Pouiller wrote:
quoted hunk ↗ jump to hunk
From: Jérôme Pouiller <jerome.pouiller@silabs.com> During the scan requests, the Tx traffic is suspended. This lock is shared by all the network interfaces. So, a scan request on one interface will block the traffic on a second interface. This causes trouble when the queued traffic contains CAB (Content After DTIM Beacon) since this traffic cannot be delayed. It could be possible to make the lock local to each interface. But It would only push the problem further. The device won't be able to send the CAB before the end of the scan. So, this patch just ignore the DTIM indication when a scan is in progress. The firmware will send another indication on the next DTIM and this time the system will be able to send the traffic just behind the beacon. The only drawback of this solution is that the stations connected to the AP will wait for traffic after the DTIM for nothing. But since the case is really rare it is not a big deal. Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com> --- drivers/staging/wfx/sta.c | 10 ++++++++++ 1 file changed, 10 insertions(+)diff --git a/drivers/staging/wfx/sta.c b/drivers/staging/wfx/sta.c index a236e5bb6914..d901588237a4 100644 --- a/drivers/staging/wfx/sta.c +++ b/drivers/staging/wfx/sta.c@@ -629,8 +629,18 @@ int wfx_set_tim(struct ieee80211_hw *hw, struct ieee80211_sta *sta, bool set) void wfx_suspend_resume_mc(struct wfx_vif *wvif, enum sta_notify_cmd notify_cmd) { + struct wfx_vif *wvif_it; + if (notify_cmd != STA_NOTIFY_AWAKE) return; + + // Device won't be able to honor CAB if a scan is in progress on any + // interface. Prefer to skip this DTIM and wait for the next one.
In one patch you drop // comments but you introduce some of your self.
+ wvif_it = NULL; + while ((wvif_it = wvif_iterate(wvif->wdev, wvif_it)) != NULL) + if (mutex_is_locked(&wvif_it->scan_lock)) + return; + if (!wfx_tx_queues_has_cab(wvif) || wvif->after_dtim_tx_allowed) dev_warn(wvif->wdev->dev, "incorrect sequence (%d CAB in queue)", wfx_tx_queues_has_cab(wvif)); -- 2.33.0