#include "event.h"
static bool
-below_assoc_threshold(struct sta_info *si_cur, struct sta_info *si_new)
+below_assoc_threshold(struct usteer_node *node_cur, struct usteer_node *node_new)
{
- int n_assoc_cur = si_cur->node->n_assoc;
- int n_assoc_new = si_new->node->n_assoc;
- bool ref_5g = si_cur->node->freq > 4000;
- bool node_5g = si_new->node->freq > 4000;
+ int n_assoc_cur = node_cur->n_assoc;
+ int n_assoc_new = node_new->n_assoc;
+ bool ref_5g = node_cur->freq > 4000;
+ bool node_5g = node_new->freq > 4000;
+
+ if (!config.load_balancing_threshold)
+ return false;
if (ref_5g && !node_5g)
n_assoc_new += config.band_steering_threshold;
}
static bool
-better_signal_strength(struct sta_info *si_cur, struct sta_info *si_new)
+better_signal_strength(int signal_cur, int signal_new)
{
- const bool is_better = si_new->signal - si_cur->signal
+ const bool is_better = signal_new - signal_cur
> (int) config.signal_diff_threshold;
if (!config.signal_diff_threshold)
}
static bool
-below_load_threshold(struct sta_info *si)
+below_load_threshold(struct usteer_node *node)
{
- return si->node->n_assoc >= config.load_kick_min_clients &&
- si->node->load > config.load_kick_threshold;
+ return node->n_assoc >= config.load_kick_min_clients &&
+ node->load > config.load_kick_threshold;
}
static bool
-has_better_load(struct sta_info *si_cur, struct sta_info *si_new)
+has_better_load(struct usteer_node *node_cur, struct usteer_node *node_new)
+{
+ return !below_load_threshold(node_cur) && below_load_threshold(node_new);
+}
+
+bool
+usteer_policy_node_below_max_assoc(struct usteer_node *node)
{
- return !below_load_threshold(si_cur) && below_load_threshold(si_new);
+ return !node->max_assoc || node->n_assoc < node->max_assoc;
}
static bool
-below_max_assoc(struct sta_info *si)
+over_min_signal(struct usteer_node *node, int signal)
{
- struct usteer_node *node = si->node;
+ if (config.min_snr && signal < usteer_snr_to_signal(node, config.min_snr))
+ return false;
- return !node->max_assoc || node->n_assoc < node->max_assoc;
+ if (config.roam_trigger_snr && signal < usteer_snr_to_signal(node, config.roam_trigger_snr))
+ return false;
+
+ return true;
}
static uint32_t
is_better_candidate(struct sta_info *si_cur, struct sta_info *si_new)
{
+ struct usteer_node *current_node = si_cur->node;
+ struct usteer_node *new_node = si_new->node;
+ int current_signal = si_cur->signal;
+ int new_signal = si_new->signal;
uint32_t reasons = 0;
- if (!below_max_assoc(si_new))
+ if (!usteer_policy_node_below_max_assoc(new_node))
+ return 0;
+
+ if (!over_min_signal(new_node, new_signal))
return 0;
- if (below_assoc_threshold(si_cur, si_new) &&
- !below_assoc_threshold(si_new, si_cur))
+ if (below_assoc_threshold(current_node, new_node) &&
+ !below_assoc_threshold(new_node, current_node))
reasons |= (1 << UEV_SELECT_REASON_NUM_ASSOC);
- if (better_signal_strength(si_cur, si_new))
+ if (better_signal_strength(current_signal, new_signal))
reasons |= (1 << UEV_SELECT_REASON_SIGNAL);
- if (has_better_load(si_cur, si_new) &&
- !has_better_load(si_cur, si_new))
+ if (has_better_load(current_node, new_node) &&
+ !has_better_load(current_node, new_node))
reasons |= (1 << UEV_SELECT_REASON_LOAD);
return reasons;
}
static struct sta_info *
-find_better_candidate(struct sta_info *si_ref, struct uevent *ev)
+find_better_candidate(struct sta_info *si_ref, struct uevent *ev, uint32_t required_criteria, uint64_t max_age)
{
- struct sta_info *si;
+ struct sta_info *si, *candidate = NULL;
struct sta *sta = si_ref->sta;
uint32_t reasons;
if (strcmp(si->node->ssid, si_ref->node->ssid) != 0)
continue;
+ if (max_age && max_age < current_time - si->seen)
+ continue;
+
reasons = is_better_candidate(si_ref, si);
if (!reasons)
continue;
- if (is_better_candidate(si, si_ref))
+ if (!(reasons & required_criteria))
continue;
if (ev) {
ev->select_reasons = reasons;
}
- return si;
+ if (!candidate || si->signal > candidate->signal)
+ candidate = si;
}
- return NULL;
+ return candidate;
}
-static int
-snr_to_signal(struct usteer_node *node, int snr)
+int
+usteer_snr_to_signal(struct usteer_node *node, int snr)
{
int noise = -95;
int min_signal;
bool ret = true;
- if (type == EVENT_TYPE_AUTH)
+ if (type == EVENT_TYPE_PROBE && !config.probe_steering)
goto out;
- if (type == EVENT_TYPE_ASSOC && !config.assoc_steering)
+ if (type == EVENT_TYPE_AUTH)
goto out;
- min_signal = snr_to_signal(si->node, config.min_connect_snr);
+ if (type == EVENT_TYPE_ASSOC) {
+ /* Check if assoc request has lower signal than min_signal.
+ * If this is the case, block assoc even when assoc steering is enabled.
+ *
+ * Otherwise, the client potentially ends up in a assoc - kick loop.
+ */
+ if (config.min_snr && si->signal < usteer_snr_to_signal(si->node, config.min_snr)) {
+ ev.reason = UEV_REASON_LOW_SIGNAL;
+ ev.threshold.cur = si->signal;
+ ev.threshold.ref = usteer_snr_to_signal(si->node, config.min_snr);
+ ret = false;
+ goto out;
+ } else if (!config.assoc_steering) {
+ goto out;
+ }
+ }
+
+ min_signal = usteer_snr_to_signal(si->node, config.min_connect_snr);
if (si->signal < min_signal) {
ev.reason = UEV_REASON_LOW_SIGNAL;
ev.threshold.cur = si->signal;
goto out;
}
- if (!find_better_candidate(si, &ev))
+ if (!find_better_candidate(si, &ev, UEV_SELECT_REASON_ALL, 0))
goto out;
ev.reason = UEV_REASON_BETTER_CANDIDATE;
out:
switch (type) {
case EVENT_TYPE_PROBE:
- ev.type = UEV_PROBE_REQ_ACCEPT;
+ ev.type = ret ? UEV_PROBE_REQ_ACCEPT : UEV_PROBE_REQ_DENY;
break;
case EVENT_TYPE_ASSOC:
- ev.type = UEV_ASSOC_REQ_ACCEPT;
+ ev.type = ret ? UEV_ASSOC_REQ_ACCEPT : UEV_ASSOC_REQ_DENY;
break;
case EVENT_TYPE_AUTH:
- ev.type = UEV_AUTH_REQ_ACCEPT;
+ ev.type = ret ? UEV_AUTH_REQ_ACCEPT : UEV_AUTH_REQ_DENY;
break;
default:
break;
}
- if (!ret)
- ev.type++;
-
if (!ret && si->stats[type].blocked_cur >= config.max_retry_band) {
ev.reason = UEV_REASON_RETRY_EXCEEDED;
ev.threshold.cur = si->stats[type].blocked_cur;
usteer_roam_set_state(struct sta_info *si, enum roam_trigger_state state,
struct uevent *ev)
{
+ /* NOP in case we remain idle */
+ if (si->roam_state == state && si->roam_state == ROAM_TRIGGER_IDLE) {
+ si->roam_tries = 0;
+ return;
+ }
+
si->roam_event = current_time;
if (si->roam_state == state) {
- if (si->roam_state == ROAM_TRIGGER_IDLE) {
- si->roam_tries = 0;
- return;
- }
-
si->roam_tries++;
} else {
si->roam_tries = 0;
usteer_event(ev);
}
+static void
+usteer_roam_sm_start_scan(struct sta_info *si, struct uevent *ev)
+{
+ /* Start scanning in case we are not timeout-constrained or timeout has expired */
+ if (!config.roam_scan_timeout ||
+ current_time > si->roam_scan_timeout_start + config.roam_scan_timeout) {
+ usteer_roam_set_state(si, ROAM_TRIGGER_SCAN, ev);
+ return;
+ }
+
+ /* We are currently in scan timeout / cooldown.
+ * Check if we are in ROAM_TRIGGER_IDLE state. Enter this state if not.
+ */
+ if (si->roam_state == ROAM_TRIGGER_IDLE)
+ return;
+
+ /* Enter idle state */
+ usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, ev);
+}
+
+static struct sta_info *
+usteer_roam_sm_found_better_node(struct sta_info *si, struct uevent *ev, enum roam_trigger_state next_state)
+{
+ uint64_t max_age = 2 * config.roam_scan_interval;
+ struct sta_info *candidate;
+
+ if (max_age > current_time - si->roam_scan_start)
+ max_age = current_time - si->roam_scan_start;
+
+ candidate = find_better_candidate(si, ev, (1 << UEV_SELECT_REASON_SIGNAL), max_age);
+ if (candidate)
+ usteer_roam_set_state(si, next_state, ev);
+
+ return candidate;
+}
+
static bool
-usteer_roam_trigger_sm(struct sta_info *si)
+usteer_roam_trigger_sm(struct usteer_local_node *ln, struct sta_info *si)
{
+ struct sta_info *candidate;
struct uevent ev = {
.si_cur = si,
};
- int min_signal;
-
- min_signal = snr_to_signal(si->node, config.roam_trigger_snr);
switch (si->roam_state) {
case ROAM_TRIGGER_SCAN:
- if (current_time - si->roam_event < config.roam_scan_interval)
+ if (!si->roam_tries) {
+ si->roam_scan_start = current_time;
+ }
+
+ /* Check if we've found a better node regardless of the scan-interval */
+ if (usteer_roam_sm_found_better_node(si, &ev, ROAM_TRIGGER_SCAN_DONE))
break;
- if (find_better_candidate(si, &ev) ||
- si->roam_scan_done > si->roam_event) {
- usteer_roam_set_state(si, ROAM_TRIGGER_SCAN_DONE, &ev);
+ /* Only scan every scan-interval */
+ if (current_time - si->roam_event < config.roam_scan_interval)
break;
- }
- if (config.roam_scan_tries &&
- si->roam_tries >= config.roam_scan_tries) {
- usteer_roam_set_state(si, ROAM_TRIGGER_WAIT_KICK, &ev);
+ /* Check if no node was found within roam_scan_tries tries */
+ if (config.roam_scan_tries && si->roam_tries >= config.roam_scan_tries) {
+ if (!config.roam_scan_timeout) {
+ /* Prepare to kick client */
+ usteer_roam_set_state(si, ROAM_TRIGGER_SCAN_DONE, &ev);
+ } else {
+ /* Kick in scan timeout */
+ si->roam_scan_timeout_start = current_time;
+ usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, &ev);
+ }
break;
}
+ /* Send beacon-request to client */
usteer_ubus_trigger_client_scan(si);
- usteer_roam_set_state(si, ROAM_TRIGGER_SCAN, &ev);
+ usteer_roam_sm_start_scan(si, &ev);
break;
case ROAM_TRIGGER_IDLE:
- if (find_better_candidate(si, &ev)) {
- usteer_roam_set_state(si, ROAM_TRIGGER_SCAN_DONE, &ev);
- break;
- }
-
- usteer_roam_set_state(si, ROAM_TRIGGER_SCAN, &ev);
+ usteer_roam_sm_start_scan(si, &ev);
break;
case ROAM_TRIGGER_SCAN_DONE:
- /* Check for stale scan results, kick back to SCAN state if necessary */
- if (current_time - si->roam_scan_done > 2 * config.roam_scan_interval) {
- usteer_roam_set_state(si, ROAM_TRIGGER_SCAN, &ev);
+ candidate = usteer_roam_sm_found_better_node(si, &ev, ROAM_TRIGGER_SCAN_DONE);
+ /* Kick back in case no better node is found */
+ if (!candidate) {
+ usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, &ev);
break;
}
- if (find_better_candidate(si, &ev))
- usteer_roam_set_state(si, ROAM_TRIGGER_WAIT_KICK, &ev);
-
+ usteer_ubus_bss_transition_request(si, 1, false, false, 100, candidate->node);
+ si->kick_time = current_time + config.roam_kick_delay;
+ usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, &ev);
break;
+ }
- case ROAM_TRIGGER_WAIT_KICK:
- if (si->signal > min_signal)
- break;
+ return false;
+}
- usteer_roam_set_state(si, ROAM_TRIGGER_NOTIFY_KICK, &ev);
- usteer_ubus_notify_client_disassoc(si);
- break;
- case ROAM_TRIGGER_NOTIFY_KICK:
- if (current_time - si->roam_event < config.roam_kick_delay * 100)
- break;
+bool usteer_policy_can_perform_roam(struct sta_info *si)
+{
+ /* Only trigger for connected STAs */
+ if (si->connected != STA_CONNECTED)
+ return false;
- usteer_roam_set_state(si, ROAM_TRIGGER_KICK, &ev);
- break;
- case ROAM_TRIGGER_KICK:
- usteer_ubus_kick_client(si);
- usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, &ev);
- return true;
- }
+ /* Skip on pending kick */
+ if (si->kick_time)
+ return false;
- return false;
+ /* Skip on rejected transition */
+ if (si->bss_transition_response.status_code && current_time - si->bss_transition_response.timestamp < config.steer_reject_timeout)
+ return false;
+
+ /* Skip on previous kick attempt */
+ if (current_time - si->roam_kick < config.roam_trigger_interval)
+ return false;
+
+ /* Skip if connection is established shorter than the trigger-interval */
+ if (current_time - si->connected_since < config.roam_trigger_interval)
+ return false;
+
+ return true;
+}
+
+static bool
+usteer_local_node_roam_sm_active(struct sta_info *si, int min_signal)
+{
+ if (!usteer_policy_can_perform_roam(si))
+ return false;
+
+ /* Signal has to be below scan / roam threshold */
+ if (si->signal >= min_signal)
+ return false;
+
+ return true;
}
static void
return;
usteer_update_time();
- min_signal = snr_to_signal(&ln->node, min_signal);
+ min_signal = usteer_snr_to_signal(&ln->node, min_signal);
list_for_each_entry(si, &ln->node.sta_info, node_list) {
- if (!si->connected || si->signal >= min_signal ||
- current_time - si->roam_kick < config.roam_trigger_interval) {
+ if (!usteer_local_node_roam_sm_active(si, min_signal)) {
usteer_roam_set_state(si, ROAM_TRIGGER_IDLE, ev);
continue;
}
* If the state machine kicked a client, other clients should wait
* until the next turn
*/
- if (usteer_roam_trigger_sm(si))
+ if (usteer_roam_trigger_sm(ln, si))
return;
}
}
static void
usteer_local_node_snr_kick(struct usteer_local_node *ln)
{
+ unsigned int min_count = DIV_ROUND_UP(config.min_snr_kick_delay, config.local_sta_update);
struct uevent ev = {
.node_local = &ln->node,
};
if (!config.min_snr)
return;
- min_signal = snr_to_signal(&ln->node, config.min_snr);
+ min_signal = usteer_snr_to_signal(&ln->node, config.min_snr);
ev.threshold.ref = min_signal;
list_for_each_entry(si, &ln->node.sta_info, node_list) {
- if (!si->connected)
+ if (si->connected != STA_CONNECTED)
continue;
- if (si->signal >= min_signal)
+ if (si->signal >= min_signal) {
+ si->below_min_snr = 0;
continue;
+ } else {
+ si->below_min_snr++;
+ }
- si->kick_count++;
+ if (si->below_min_snr <= min_count)
+ continue;
ev.type = UEV_SIGNAL_KICK;
ev.threshold.cur = si->signal;
}
}
-void
-usteer_local_node_kick(struct usteer_local_node *ln)
+static void
+usteer_local_node_load_kick(struct usteer_local_node *ln)
{
struct usteer_node *node = &ln->node;
struct sta_info *kick1 = NULL, *kick2 = NULL;
};
unsigned int min_count = DIV_ROUND_UP(config.load_kick_delay, config.local_sta_update);
- usteer_local_node_roam_check(ln, &ev);
- usteer_local_node_snr_kick(ln);
-
if (!config.load_kick_enabled || !config.load_kick_threshold ||
!config.load_kick_delay)
return;
list_for_each_entry(si, &ln->node.sta_info, node_list) {
struct sta_info *tmp;
- if (!si->connected)
+ if (si->connected != STA_CONNECTED)
continue;
if (is_more_kickable(kick1, si))
kick1 = si;
- tmp = find_better_candidate(si, NULL);
+ tmp = find_better_candidate(si, NULL, (1 << UEV_SELECT_REASON_LOAD), 0);
if (!tmp)
continue;
out:
usteer_event(&ev);
}
+
+static void
+usteer_local_node_perform_kick(struct usteer_local_node *ln)
+{
+ struct sta_info *si;
+
+ list_for_each_entry(si, &ln->node.sta_info, node_list) {
+ if (!si->kick_time || si->kick_time > current_time)
+ continue;
+
+ usteer_ubus_kick_client(si);
+ }
+}
+
+void
+usteer_local_node_kick(struct usteer_local_node *ln)
+{
+ struct uevent ev = {
+ .node_local = &ln->node,
+ };
+
+ usteer_local_node_perform_kick(ln);
+
+ usteer_local_node_snr_kick(ln);
+ usteer_local_node_load_kick(ln);
+ usteer_local_node_roam_check(ln, &ev);
+}
projects / project / usteer.git / blobdiff