CHROMIUM: Remove SNR considersation in need_to_roam
This partially reverts commit
5e7a79df1e581eeca3b5b976c54e32d3e015078c.
BUG=None (TBD)
TEST=None (TBD)
Change-Id: I9bb507102c928b443a6d08d315dd34af3d952675
Signed-off-by: Kirtika Ruchandani <kirtika@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/896391
Commit-Ready: Matthew Wang <matthewmwang@chromium.org>
Tested-by: Matthew Wang <matthewmwang@chromium.org>
Reviewed-by: Matthew Wang <matthewmwang@chromium.org>
(cherry picked from commit 67df2c8a3ee26e67b2f13008b40277d88e51b938)
Reviewed-on: https://chromium-review.googlesource.com/898187
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index 843b9d1..4783482 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -1425,6 +1425,16 @@
return 1; /* current BSS not seen in the last scan */
#ifndef CONFIG_NO_ROAMING
+ wpa_dbg(wpa_s, MSG_DEBUG, "Considering within-ESS reassociation");
+ wpa_dbg(wpa_s, MSG_DEBUG, "Current BSS: " MACSTR
+ " level=%d snr=%d est_throughput=%u",
+ MAC2STR(current_bss->bssid), current_bss->level,
+ current_bss->snr, current_bss->est_throughput);
+ wpa_dbg(wpa_s, MSG_DEBUG, "Selected BSS: " MACSTR
+ " level=%d snr=%d est_throughput=%u",
+ MAC2STR(selected->bssid), selected->level,
+ selected->snr, selected->est_throughput);
+
if (wpa_s->current_ssid->bssid_set &&
os_memcmp(selected->bssid, wpa_s->current_ssid->bssid, ETH_ALEN) ==
0) {
@@ -1448,82 +1458,32 @@
return 0;
}
- if (current_bss->noise && selected->noise) {
- int current_snr, selected_snr;
- /*
- * We have the noise floor for both stations; use SNR
- * instead of signal level to decide whether to roam.
- */
- current_snr = MIN(current_bss->level - current_bss->noise,
- GREAT_SNR);
- /* TOD0(sleffler) depends on band? */
- if (current_snr >= wpa_s->conf->roam_threshold) {
- /*
- * Never roam unless signal is "weak".
- */
- wpa_dbg(wpa_s, MSG_DEBUG, "Skip roam - current snr %d "
- "exceeds weak threshold", current_snr);
- return 0;
- }
- selected_snr = MIN(selected->level - selected->noise,
- GREAT_SNR);
+ min_diff = 2;
+ if (current_bss->level < 0) {
+ if (current_bss->level < -85)
+ min_diff = 1;
+ else if (current_bss->level < -80)
+ min_diff = 2;
+ else if (current_bss->level < -75)
+ min_diff = 3;
+ else if (current_bss->level < -70)
+ min_diff = 4;
+ else
+ min_diff = 5;
+ }
- wpa_dbg(wpa_s, MSG_DEBUG, "Considering within-ESS reassociation");
- wpa_dbg(wpa_s, MSG_DEBUG, "Current BSS: " MACSTR " snr=%d",
- MAC2STR(current_bss->bssid), current_snr);
- wpa_dbg(wpa_s, MSG_DEBUG, "Selected BSS: " MACSTR " snr=%d",
- MAC2STR(selected->bssid), selected_snr);
+ if (to_5ghz) {
+ /* Make it easier to move to 5 GHz band */
+ if (min_diff > 2)
+ min_diff -= 2;
+ else
+ min_diff = 0;
+ }
- /*
- * Never roam for less than ROAM_SNR_MIN_DIFF improvement
- * (should be at least 3dBm); that represents at least 2x
- * signal strength. Note that we know the SNR for the
- * current AP is <= ROAM_SNR_WEAK_THRESHOLD so ROAM_SNR_MIN_DIFF
- * should represent a significant improvement.
- *
- * NB: wpa_scan_result_compar usually sorts scan results by
- * SNR but under some rare occurences this may not be
- * true and this is handled here
- */
- if ((selected_snr - current_snr) < wpa_s->conf->roam_min) {
- wpa_dbg(wpa_s, MSG_DEBUG, "Skip roam - selected snr "
- "not enough better than current");
- return 0;
- }
- } else {
- int min_diff;
-
- wpa_dbg(wpa_s, MSG_DEBUG, "Considering within-ESS reassociation");
- wpa_dbg(wpa_s, MSG_DEBUG, "Current BSS: " MACSTR " level=%d",
- MAC2STR(current_bss->bssid), current_bss->level);
- wpa_dbg(wpa_s, MSG_DEBUG, "Selected BSS: " MACSTR " level=%d",
- MAC2STR(selected->bssid), selected->level);
-
- min_diff = 2;
- if (current_bss->level < 0) {
- if (current_bss->level < -85)
- min_diff = 1;
- else if (current_bss->level < -80)
- min_diff = 2;
- else if (current_bss->level < -75)
- min_diff = 3;
- else if (current_bss->level < -70)
- min_diff = 4;
- else
- min_diff = 5;
- }
- if (to_5ghz) {
- /* Make it easier to move to 5 GHz band */
- if (min_diff > 2)
- min_diff -= 2;
- else
- min_diff = 0;
- }
- if (abs(current_bss->level - selected->level) < min_diff) {
- wpa_dbg(wpa_s, MSG_DEBUG, "Skip roam - too small "
- "difference in signal level");
- return 0;
- }
+ if (abs(current_bss->level - selected->level) < min_diff) {
+ wpa_dbg(wpa_s, MSG_DEBUG, "Skip roam - too small difference "
+ "in signal level");
+ return 0;
}
return 1;
