Bluetooth: Sort to-be-resolved devices by RSSI during discovery

This patch makes sure that devices with stronger signal (RSSI closer to
0) are sorted first in the resolve list and will therefore get their
names resolved first during device discovery. Since it's more likely
that the device the user is trying to discover has a strong signal due
to its proximity this ensures that the user gets the "device found"
event for it more quickly.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index f9c88251fe1a1e2e3ef918c2738a72b5e94ec63e..59e3541e9fc7d6e80283bd3aa3690f759f371c88 100644 (file)
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -395,6 +395,8 @@ struct inquiry_entry *hci_inquiry_cache_lookup_unknown(struct hci_dev *hdev,
 struct inquiry_entry *hci_inquiry_cache_lookup_resolve(struct hci_dev *hdev,
                                                        bdaddr_t *bdaddr,
                                                        int state);
+void hci_inquiry_cache_update_resolve(struct hci_dev *hdev,
+                                               struct inquiry_entry *ie);
 bool hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data,
                                                        bool name_known);
 

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 3acb23cf6ee4a2b641dadd7cd89cd9af22798307..9963121028e4f39c8c0b963474a6cfb653368435 100644 (file)
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -457,6 +457,25 @@ struct inquiry_entry *hci_inquiry_cache_lookup_resolve(struct hci_dev *hdev,
        return NULL;
 }
 
+void hci_inquiry_cache_update_resolve(struct hci_dev *hdev,
+                                               struct inquiry_entry *ie)
+{
+       struct discovery_state *cache = &hdev->discovery;
+       struct list_head *pos = &cache->resolve;
+       struct inquiry_entry *p;
+
+       list_del(&ie->list);
+
+       list_for_each_entry(p, &cache->resolve, list) {
+               if (p->name_state != NAME_PENDING &&
+                               abs(p->data.rssi) >= abs(ie->data.rssi))
+                       break;
+               pos = &p->list;
+       }
+
+       list_add(&ie->list, pos);
+}
+
 bool hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data,
                                                        bool name_known)
 {
@@ -466,8 +485,15 @@ bool hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data,
        BT_DBG("cache %p, %s", cache, batostr(&data->bdaddr));
 
        ie = hci_inquiry_cache_lookup(hdev, &data->bdaddr);
-       if (ie)
+       if (ie) {
+               if (ie->name_state == NAME_NEEDED &&
+                                               data->rssi != ie->data.rssi) {
+                       ie->data.rssi = data->rssi;
+                       hci_inquiry_cache_update_resolve(hdev, ie);
+               }
+
                goto update;
+       }
 
        /* Entry not in the cache. Add new one. */
        ie = kzalloc(sizeof(struct inquiry_entry), GFP_ATOMIC);

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 3de1e909471af10afb8b2ff5c0a5c51ace889d33..2dae2e8f6234c410cfca60701c287f2bb1d9c544 100644 (file)
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -2043,7 +2043,7 @@ static int confirm_name(struct sock *sk, u16 index, unsigned char *data,
                list_del(&e->list);
        } else {
                e->name_state = NAME_NEEDED;
-               list_move(&e->list, &hdev->discovery.resolve);
+               hci_inquiry_cache_update_resolve(hdev, e);
        }
 
        err = 0;