jeltz/hostap
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

SME: Optimize OBSS scanning

Browse source 
Include only the potentially affected channel range in OBSS scans to
reduce the amount of offchannel time needed for scanning when requested
by the AP.

Signed-off-by: Jouni Malinen <j@w1.fi>
This commit is contained in:
Jouni Malinen 2014-12-22 22:07:03 +02:00
parent 0acc2c809d
commit d97a3c4885
2 changed files with 55 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

59
wpa_supplicant/sme.c
View file

@ -1253,28 +1253,72 @@ static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
} }
static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s, static void wpa_obss_scan_freqs_list(struct wpa_supplicant *wpa_s,
enum hostapd_hw_mode band, struct wpa_driver_scan_params *params)
struct wpa_driver_scan_params *params)
{ {
/* Include only supported channels for the specified band */ /* Include only affected channels */
struct hostapd_hw_modes *mode; struct hostapd_hw_modes *mode;
int count, i; int count, i;
int start, end;
mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band); mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes,
HOSTAPD_MODE_IEEE80211G);
if (mode == NULL) { if (mode == NULL) {
/* No channels supported in this band - use empty list */ /* No channels supported in this band - use empty list */
params->freqs = os_zalloc(sizeof(int)); params->freqs = os_zalloc(sizeof(int));
return; return;
} }
if (wpa_s->sme.ht_sec_chan == HT_SEC_CHAN_UNKNOWN &&
wpa_s->current_bss) {
const u8 *ie;
ie = wpa_bss_get_ie(wpa_s->current_bss, WLAN_EID_HT_OPERATION);
if (ie && ie[1] >= 2) {
u8 o;
o = ie[3] & HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK;
if (o == HT_INFO_HT_PARAM_SECONDARY_CHNL_ABOVE)
wpa_s->sme.ht_sec_chan = HT_SEC_CHAN_ABOVE;
else if (o == HT_INFO_HT_PARAM_SECONDARY_CHNL_BELOW)
wpa_s->sme.ht_sec_chan = HT_SEC_CHAN_BELOW;
}
}
start = wpa_s->assoc_freq - 10;
end = wpa_s->assoc_freq + 10;
switch (wpa_s->sme.ht_sec_chan) {
case HT_SEC_CHAN_UNKNOWN:
/* HT40+ possible on channels 1..9 */
if (wpa_s->assoc_freq <= 2452)
start -= 20;
/* HT40- possible on channels 5-13 */
if (wpa_s->assoc_freq >= 2432)
end += 20;
break;
case HT_SEC_CHAN_ABOVE:
end += 20;
break;
case HT_SEC_CHAN_BELOW:
start -= 20;
break;
}
wpa_printf(MSG_DEBUG,
"OBSS: assoc_freq %d possible affected range %d-%d",
wpa_s->assoc_freq, start, end);
params->freqs = os_calloc(mode->num_channels + 1, sizeof(int)); params->freqs = os_calloc(mode->num_channels + 1, sizeof(int));
if (params->freqs == NULL) if (params->freqs == NULL)
return; return;
for (count = 0, i = 0; i < mode->num_channels; i++) { for (count = 0, i = 0; i < mode->num_channels; i++) {
int freq;
if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED) if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
continue; continue;
params->freqs[count++] = mode->channels[i].freq; freq = mode->channels[i].freq;
if (freq - 10 >= end || freq + 10 <= start)
continue; /* not affected */
params->freqs[count++] = freq;
} }
} }
@ -1290,7 +1334,7 @@ static void sme_obss_scan_timeout(void *eloop_ctx, void *timeout_ctx)
} }
os_memset(&params, 0, sizeof(params)); os_memset(&params, 0, sizeof(params));
wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G, &params); wpa_obss_scan_freqs_list(wpa_s, &params);
params.low_priority = 1; params.low_priority = 1;
wpa_printf(MSG_DEBUG, "SME OBSS: Request an OBSS scan"); wpa_printf(MSG_DEBUG, "SME OBSS: Request an OBSS scan");
@ -1315,6 +1359,7 @@ void sme_sched_obss_scan(struct wpa_supplicant *wpa_s, int enable)
eloop_cancel_timeout(sme_obss_scan_timeout, wpa_s, NULL); eloop_cancel_timeout(sme_obss_scan_timeout, wpa_s, NULL);
wpa_s->sme.sched_obss_scan = 0; wpa_s->sme.sched_obss_scan = 0;
wpa_s->sme.ht_sec_chan = HT_SEC_CHAN_UNKNOWN;
if (!enable) if (!enable)
return; return;

3
wpa_supplicant/wpa_supplicant_i.h
View file

@ -675,6 +675,9 @@ struct wpa_supplicant {
* SA Query transaction identifiers */ * SA Query transaction identifiers */
struct os_reltime sa_query_start; struct os_reltime sa_query_start;
struct os_reltime last_unprot_disconnect; struct os_reltime last_unprot_disconnect;
enum { HT_SEC_CHAN_UNKNOWN,
HT_SEC_CHAN_ABOVE,
HT_SEC_CHAN_BELOW } ht_sec_chan;
u8 sched_obss_scan; u8 sched_obss_scan;
u16 obss_scan_int; u16 obss_scan_int;
u16 bss_max_idle_period; u16 bss_max_idle_period;