[Bluez,v1] src/adv_monitor: Remove checking in device lost timeout

Commit Message

Howard Chung June 28, 2021, 2:37 a.m. UTC

From: Yun-Hao Chung <[e-mail]>

The time check in device lost timeout could cause DeviceLost never being
reported because of the following reasons:

1. Timer created in timeout_add_seconds, which calls
   g_timeout_add_seconds_full internally, can be fired one second
   earlier than |timeout| seconds.
2. When handle_device_lost_timeout is invoked early, time diff between
   |curr_time| and |last_seen| could be less than |low_rssi_timeout|. In
   this case, since handle_device_lost always returns FALSE, the
   timer will be removed, but DeviceLost has not been reported yet.
3. If we never receives any advertisement from that peer since then,
   DeviceLost will never be reported.

We can remove the checking in handle_device_lost_time because we restart
or remove the timer whenever an advertisement is recevied.

Reviewed-by: [e-mail]
Reviewed-by: [e-mail]
Reviewed-by: [e-mail]
---

 src/adv_monitor.c | 27 ++++++---------------------
 1 file changed, 6 insertions(+), 21 deletions(-)

Comments

[e-mail] June 28, 2021, 3:06 a.m. UTC | #1

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=507761

---Test result---

Test Summary:
CheckPatch                    FAIL      0.34 seconds
GitLint                       PASS      0.12 seconds
Prep - Setup ELL              PASS      46.61 seconds
Build - Prep                  PASS      0.11 seconds
Build - Configure             PASS      8.27 seconds
Build - Make                  PASS      203.50 seconds
Make Check                    PASS      9.79 seconds
Make Distcheck                PASS      242.81 seconds
Build w/ext ELL - Configure   PASS      8.37 seconds
Build w/ext ELL - Make        PASS      191.68 seconds

Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script with rule in .checkpatch.conf
Output:
src/adv_monitor: Remove checking in device lost timeout
WARNING:TYPO_SPELLING: 'recevied' may be misspelled - perhaps 'received'?
#20: 
or remove the timer whenever an advertisement is recevied.
                                                 ^^^^^^^^

- total: 0 errors, 1 warnings, 37 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

"[PATCH] src/adv_monitor: Remove checking in device lost timeout" has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.


##############################
Test: GitLint - PASS
Desc: Run gitlint with rule in .gitlint

##############################
Test: Prep - Setup ELL - PASS
Desc: Clone, build, and install ELL

##############################
Test: Build - Prep - PASS
Desc: Prepare environment for build

##############################
Test: Build - Configure - PASS
Desc: Configure the BlueZ source tree

##############################
Test: Build - Make - PASS
Desc: Build the BlueZ source tree

##############################
Test: Make Check - PASS
Desc: Run 'make check'

##############################
Test: Make Distcheck - PASS
Desc: Run distcheck to check the distribution

##############################
Test: Build w/ext ELL - Configure - PASS
Desc: Configure BlueZ source with '--enable-external-ell' configuration

##############################
Test: Build w/ext ELL - Make - PASS
Desc: Build BlueZ source with '--enable-external-ell' configuration



---
Regards,
Linux Bluetooth

Patch

diff --git a/src/adv_monitor.c b/src/adv_monitor.c
index 17f1777eb1da..715ac5904b9a 100644
--- a/src/adv_monitor.c
+++ b/src/adv_monitor.c
@@ -1884,31 +1884,16 @@  static bool handle_device_lost_timeout(gpointer user_data)
 {
 	struct adv_monitor_device *dev = user_data;
 	struct adv_monitor *monitor = dev->monitor;
-	time_t curr_time = time(NULL);
 
-	DBG("Device Lost timeout triggered for device %p "
-	    "for the Adv Monitor at path %s", dev->device, monitor->path);
+	DBG("Device Lost timeout triggered for device %p. Calling DeviceLost() "
+	    "on Adv Monitor of owner %s at path %s", dev->device,
+					    monitor->app->owner, monitor->path);
 
+	g_dbus_proxy_method_call(monitor->proxy, "DeviceLost",
+				 report_device_state_setup,
+				 NULL, dev->device, NULL);
 	dev->lost_timer = 0;
 
-	if (dev->found && dev->last_seen) {
-		/* We were tracking for the Low RSSI filter. Check if there is
-		 * any Adv received after the timeout function is invoked.
-		 * If not, report the Device Lost event.
-		 */
-		if (difftime(curr_time, dev->last_seen) >=
-		    monitor->rssi.low_rssi_timeout) {
-			dev->found = false;
-
-			DBG("Calling DeviceLost() on Adv Monitor of owner %s "
-			    "at path %s", monitor->app->owner, monitor->path);
-
-			g_dbus_proxy_method_call(monitor->proxy, "DeviceLost",
-						 report_device_state_setup,
-						 NULL, dev->device, NULL);
-		}
-	}
-
 	return FALSE;
 }