[PATCH 00/11] Initial sched_scan support in wpa_supplicant

[Matt Causey]

On Tue, Sep 27, 2011 at 3:21 PM, Luciano Coelho <coelho at ti.com> wrote:
> Known issues:
> -------------
>
> * I have implemented a rather simple algorithm that is used when we
> ?need to scan for more than the maximum SSIDs supported by the
> ?driver. ?In this case, we need to eventually stop the sched_scan and
> ?start a new one with the remaining SSIDs. ?In this implementation, I
> ?always start with a timeout of max_sched_scan_ssids * 2 seconds and
> ?an interval of 2 seconds. ?After the timeout, I double the scan
> ?interval and halve the timeout. ?This backing off algorithm is used
> ?because the SSIDs are supposedly sorted in order of importance, so
> ?we spend less time and with longer intervals when scanning lower
> ?priority SSIDs.

I know you mentioned that sched_scan only happens at start, fail, and
disconnect, but in your testing, what is the impact of the scanning to
traffic that's passing over the wireless card?  In my experience more
time spent scanning means more time that user traffic is delayed or
dropped, so I was just wondering if you have seen similar results.

--
Matt



> Luciano Coelho (11):
> ?wpa_s: add scheduled scan driver operations
> ?nl80211: add scheduled scan support
> ?wpa_s: use sched_scan in driver init
> ?wpa_s: Increase number of SSIDs per scan
> ?wpa_s: check if sched_scan is supported before using it
> ?nl80211: check if sched_scan is supported in wiphy info
> ?wpa_s: add filter support to scheduled scans
> ?nl80211: add support for sched_scan filtering
> ?wpa_s: reorganize P2P and WPS scan code
> ?wpa_s: add delayed scheduled scan request
> ?wpa_s: add extra IEs for P2P and WPS in scheduled scan probe reqs
>
> ?src/drivers/driver.h ? ? ? ? ? ? ?| ? 40 ++++-
> ?src/drivers/driver_nl80211.c ? ? ?| ?178 +++++++++++++++++
> ?wpa_supplicant/driver_i.h ? ? ? ? | ? 17 ++
> ?wpa_supplicant/events.c ? ? ? ? ? | ? 17 ++-
> ?wpa_supplicant/scan.c ? ? ? ? ? ? | ?394 +++++++++++++++++++++++++++++-------
> ?wpa_supplicant/scan.h ? ? ? ? ? ? | ? ?4 +
> ?wpa_supplicant/sme.c ? ? ? ? ? ? ?| ? ?1 +
> ?wpa_supplicant/wpa_supplicant.c ? | ? 12 +-
> ?wpa_supplicant/wpa_supplicant_i.h | ? 10 +
> ?9 files changed, 591 insertions(+), 82 deletions(-)
>
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