| Message ID | 20211025121343.BlueZ.v4.1.I7f6bdb9282c1e12ffc6c662674678f2b1cb69182@changeid (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Luiz Von Dentz |
| Headers | show |
| Series | Add Advertisement Monitor Device Found/Lost events | expand |
| Context | Check | Description |
|---|---|---|
| tedd_an/checkpatch | success | Checkpatch PASS |
| tedd_an/gitlint | success | Gitlint PASS |
| tedd_an/setupell | success | Setup ELL PASS |
| tedd_an/buildprep | success | Build Prep PASS |
| tedd_an/build | success | Build Configuration PASS |
| tedd_an/makecheck | success | Make Check PASS |
| tedd_an/makedistcheck | success | Make Distcheck PASS |
| tedd_an/build_extell | success | Build External ELL PASS |
| tedd_an/build_extell_make | success | Build Make with External ELL PASS |
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=569881 ---Test result--- Test Summary: CheckPatch PASS 4.39 seconds GitLint PASS 2.90 seconds Prep - Setup ELL PASS 52.11 seconds Build - Prep PASS 0.54 seconds Build - Configure PASS 9.39 seconds Build - Make PASS 225.67 seconds Make Check PASS 9.84 seconds Make Distcheck PASS 266.48 seconds Build w/ext ELL - Configure PASS 9.65 seconds Build w/ext ELL - Make PASS 214.45 seconds --- Regards, Linux Bluetooth
Hi Manish, > This patch introduces new MGMT events to indicate that the controller > has started/stopped tracking a particular device matching one of the > already added Advertisement Monitor. > > --- > > Changes in v4: > - Add Advertisement Monitor Device Found event, make Address_Type 0 as > reserved. > > Changes in v3: > - Discard changes to the Device Found event and notify bluetoothd only > when the controller stops monitoring the device via new Device Lost > event. > > Changes in v2: > - Instead of creating a new 'Device Tracking' event, add a flag 'Device > Tracked' in the existing 'Device Found' event and add a new 'Device > Lost' event to indicate that the controller has stopped tracking that > device. > > doc/mgmt-api.txt | 50 +++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 49 insertions(+), 1 deletion(-) > > diff --git a/doc/mgmt-api.txt b/doc/mgmt-api.txt > index 5355fedb0..32dd8c0f2 100644 > --- a/doc/mgmt-api.txt > +++ b/doc/mgmt-api.txt > @@ -107,7 +107,8 @@ Configuration command, Default Runtime Configuration Changed event, Get > Device Flags command, Set Device Flags command, Device Flags Changed event, > Read Advertisement Monitor Features command, Add Advertisement Patterns > Monitor command, Remove Advertisement Monitor command, Advertisement Monitor > -Added event and Advertisement Monitor Removed event. > +Added event, Advertisement Monitor Removed event, Advertisement Monitor Device > +Found event and Advertisement Monitor Device Lost event. we need to increase the mgmt version and add the new commands to that section. Leave this out of this patch and put it into a separate one. > > Example > @@ -4910,3 +4911,50 @@ Controller Resume Event > Address_Type. Otherwise, Address and Address_Type will both be zero. > > This event will be sent to all management sockets. > + > + > +Advertisement Monitor Device Found Event > +======================================== > + > + Event code: 0x002f > + Controller Index: <controller_id> > + Event Parameters: Monitor_Handle (2 Octets) > + Address (6 Octets) > + Address_Type (1 Octet) > + > + This event indicates that the controller has started tracking a device > + matching an Advertisement Monitor with handle Monitor_Handle. > + > + The address of the device being tracked will be shared in Address and > + Address_Type. > + > + Possible values for the Address_Type parameter: > + 0 Reserved (not in use) > + 1 LE Public > + 2 LE Random > + > + This event will be sent to all management sockets. My initial thought was actually to include all the fields from Device Found Event here as well. So that in case we are using advertising monitor, we just need to worry about this event only. Thoughts? > + > + > +Advertisement Monitor Device Lost Event > +======================================= > + > + Event code: 0x0030 > + Controller Index: <controller_id> > + Event Parameters: Monitor_Handle (2 Octets) > + Address (6 Octets) > + Address_Type (1 Octet) > + > + This event indicates that the controller has stopped tracking a device > + that was being tracked by an Advertisement Monitor with handle > + Monitor_Handle. > + > + The address of the device being tracked will be shared in Address and > + Address_Type. > + > + Possible values for the Address_Type parameter: > + 0 Reserved (not in use) > + 1 LE Public > + 2 LE Random > + > + This event will be sent to all management sockets. Regards Marcel
Hi Manish, > > > > Example > > @@ -4910,3 +4911,50 @@ Controller Resume Event > > Address_Type. Otherwise, Address and Address_Type will both be zero. > > > > This event will be sent to all management sockets. > > + > > + > > +Advertisement Monitor Device Found Event > > +======================================== > > + > > + Event code: 0x002f > > + Controller Index: <controller_id> > > + Event Parameters: Monitor_Handle (2 Octets) > > + Address (6 Octets) > > + Address_Type (1 Octet) > > + > > + This event indicates that the controller has started tracking a device > > + matching an Advertisement Monitor with handle Monitor_Handle. > > + > > + The address of the device being tracked will be shared in Address and > > + Address_Type. > > + > > + Possible values for the Address_Type parameter: > > + 0 Reserved (not in use) > > + 1 LE Public > > + 2 LE Random > > + > > + This event will be sent to all management sockets. > > My initial thought was actually to include all the fields from Device Found Event here as well. So that in case we are using advertising monitor, we just need to worry about this event only. Thoughts? > The controller sends advertising reports in addition to the MSFT_Monitor_Device event. This event is reported only twice per bt-device (at start and at end of the monitoring); and it includes only the device addr and addr type [1]. To include other fields from the Device Found event, we need to buffer MSFT_Monitor_Device in the kernel and wait for the subsequent advertising report before we can send it to the bluetoothd. I feel this will unnecessarily complicate the logic in the kernel. > > This event will be used to invoke DeviceFound/Lost on the interface only when we are completely offloading monitoring to the controller (i.e. when the Sampling_Period is set to 0xFF). When the Sampling_Period is set to 0xFF, the controller sends only one advertisement report per monitoring period [2]. So, we need to rely on the MSFT_Monitor_Device controller event for RSSI and timeouts tracking. In other cases, as the bluetoothd receives more than one advertisement report, it can perform RSSI and timeouts tracking. > > So, I think it is better to pass on this event as it is to the bluetoothd and let the advertisement monitoring in the bluetoothd handle it. Let me know what you think about this? the kernel has to buffer events related to advertising reports and inquiry results already anyway. That is just the cost of business and it is the job of the kernel to do exactly that. I do not want to dumb down the kernel into a vendor extension passthrough since that is always going to come back and bite you. My current thinking is actually that unless Start Discovery triggers a discovery procedure, device that are monitored, should get its own report out path via mgmt. So the kernel would send Advertising Monitor Device Found Event (most likely with a flag for tracking started) and subsequence events of the same type whenever it gets updated. I mean, the kernel should track the state when a device is tracked anyway. It has to keep track of these things. In case of power down or reset or anything, the kernel needs to generate the Device Lost event to keeps this all in sync. Otherwise userspace is left to figure out what happens. We can not have that. This is similar to when a process dies, the kernel cleans up all open file descriptors. That is the basic paradigm that we have enforced with mgmt. If bluetoothd dies or restarts, we can get back to a state where we now all the details without having to hard reset hardware. One way to lock at this is always from the point of something that is not bluetoothd. Any other user of mgmt API needs to be sound and have a good API contract as well. Kernel APIs that are only designed with one daemon in mind are awful and cause major problems along the road. That all said, we can do this as above, but I would explore the option of doing it with my proposal and really focus on completely offload of the monitoring the controller. Regards Marcel
Hi Manish, On Sun, Oct 31, 2021 at 10:53 PM Manish Mandlik <mmandlik@google.com> wrote: > > Hi Marcel, > > > On Tue, Oct 26, 2021 at 4:33 AM Marcel Holtmann <marcel@holtmann.org> wrote: >> >> Hi Manish, >> >> > > >> > > Example >> > > @@ -4910,3 +4911,50 @@ Controller Resume Event >> > > Address_Type. Otherwise, Address and Address_Type will both be zero. >> > > >> > > This event will be sent to all management sockets. >> > > + >> > > + >> > > +Advertisement Monitor Device Found Event >> > > +======================================== >> > > + >> > > + Event code: 0x002f >> > > + Controller Index: <controller_id> >> > > + Event Parameters: Monitor_Handle (2 Octets) >> > > + Address (6 Octets) >> > > + Address_Type (1 Octet) >> > > + >> > > + This event indicates that the controller has started tracking a device >> > > + matching an Advertisement Monitor with handle Monitor_Handle. >> > > + >> > > + The address of the device being tracked will be shared in Address and >> > > + Address_Type. >> > > + >> > > + Possible values for the Address_Type parameter: >> > > + 0 Reserved (not in use) >> > > + 1 LE Public >> > > + 2 LE Random >> > > + >> > > + This event will be sent to all management sockets. >> > >> > My initial thought was actually to include all the fields from Device Found Event here as well. So that in case we are using advertising monitor, we just need to worry about this event only. Thoughts? >> > The controller sends advertising reports in addition to the MSFT_Monitor_Device event. This event is reported only twice per bt-device (at start and at end of the monitoring); and it includes only the device addr and addr type [1]. To include other fields from the Device Found event, we need to buffer MSFT_Monitor_Device in the kernel and wait for the subsequent advertising report before we can send it to the bluetoothd. I feel this will unnecessarily complicate the logic in the kernel. >> > >> > This event will be used to invoke DeviceFound/Lost on the interface only when we are completely offloading monitoring to the controller (i.e. when the Sampling_Period is set to 0xFF). When the Sampling_Period is set to 0xFF, the controller sends only one advertisement report per monitoring period [2]. So, we need to rely on the MSFT_Monitor_Device controller event for RSSI and timeouts tracking. In other cases, as the bluetoothd receives more than one advertisement report, it can perform RSSI and timeouts tracking. >> > >> > So, I think it is better to pass on this event as it is to the bluetoothd and let the advertisement monitoring in the bluetoothd handle it. Let me know what you think about this? >> >> the kernel has to buffer events related to advertising reports and inquiry results already anyway. That is just the cost of business and it is the job of the kernel to do exactly that. >> >> I do not want to dumb down the kernel into a vendor extension passthrough since that is always going to come back and bite you. My current thinking is actually that unless Start Discovery triggers a discovery procedure, device that are monitored, should get its own report out path via mgmt. >> >> So the kernel would send Advertising Monitor Device Found Event (most likely with a flag for tracking started) and subsequence events of the same type whenever it gets updated. I mean, the kernel should track the state when a device is tracked anyway. It has to keep track of these things. In case of power down or reset or anything, the kernel needs to generate the Device Lost event to keeps this all in sync. Otherwise userspace is left to figure out what happens. We can not have that. This is similar to when a process dies, the kernel cleans up all open file descriptors. That is the basic paradigm that we have enforced with mgmt. If bluetoothd dies or restarts, we can get back to a state where we now all the details without having to hard reset hardware. >> >> One way to lock at this is always from the point of something that is not bluetoothd. Any other user of mgmt API needs to be sound and have a good API contract as well. Kernel APIs that are only designed with one daemon in mind are awful and cause major problems along the road. >> >> That all said, we can do this as above, but I would explore the option of doing it with my proposal and really focus on completely offload of the monitoring the controller. > > > Thanks for the explanation. I see your point. Based on that I’d like to propose the following changes to the bluetooth kernel and user space to take all the advantages of the controller offloading whenever available. Let me know if it sounds good? > > Existing controller behavior (based on the MSFT extension specification): > - Whenever the controller starts monitoring a device, it first sends the MSFT_Monitor_Device event with Monitor_State as 1 and provides the matched Monitor_Id and device address. > - Based on the Sampling_Period configured, it then sends one or more LE Advertisement Reports for that device during the monitoring period. > - Whenever the controller stops monitoring a device, it again sends the MSFT_Monitor_Device event but with Monitor_State as 0 and provides the Monitor_Id and device address of the device that was being tracked. > > Proposed kernel behavior: > - Upon receipt of the MSFT_Monitor_Device event with Monitor_State 1, the kernel will buffer this event until it receives the subsequent LE Advertisement Report(s). > - After receiving the first advertisement report for the monitored device, kernel will generate the “Adv Monitor Device Found” MGMT event which is identical to the “Device Found” MGMT event, but will have additional Monitor_Handle information for the matched monitor. > - A separate Device_Tracked flag is not required since this event itself indicates that the device is being tracked. > - If the active scanning is in progress, the existing “Device Found” event will also be generated before generating the “Adv Monitor Device Found” event. > - For the subsequent advertisement reports (if any) for the monitored device, if the active scanning is in progress, only the existing "Device Found" event will be generated; else, only the "Adv Monitor Device Found" event will be generated. > - Upon receipt of the MSFT_Monitor_Device event with Monitor_State 0, the kernel will generate the “Adv Monitor Device Lost” MGMT event with the Monitor_Handle and device address of the device that was being tracked. > - Also, in case of power down or reset, the kernel will generate the "Adv Monitor Device Lost" event for the monitored devices. > > Proposed user space behavior: > - Whenever the controller offloading is available, bluetoothd will only use the “Adv Monitor Device Found” and “Adv Monitor Device Lost” event for performing monitoring related functions and SW based filtering will be completely disabled as Monitor_Handle will be available from the kernel/controller and can be used to notify respective applications on DeviceFound/DeviceLost. > - Whenever the controller offloading is NOT available, bluetoothd will use the existing “Device Found” event and perform SW based filtering as it is doing right now. > - “Adv Monitor Device Found” event will also be used to create/update the found device when active scanning is NOT in progress. Are you still working on this or are you waiting for some feedback on the above, at first glance it looks proper. Btw, it would be great if these changes are accompanied with mgmt-tester tests since vhci has support for MSFT commands and we can emulate such code paths.
Hi Manish, On Mon, Nov 8, 2021 at 9:30 PM Manish Mandlik <mmandlik@google.com> wrote: > > Hi Luiz, > > On Mon, Nov 8, 2021 at 5:57 PM Luiz Augusto von Dentz <luiz.dentz@gmail.com> wrote: >> >> Hi Manish, >> >> On Sun, Oct 31, 2021 at 10:53 PM Manish Mandlik <mmandlik@google.com> wrote: >> > >> > Hi Marcel, >> > >> > >> > On Tue, Oct 26, 2021 at 4:33 AM Marcel Holtmann <marcel@holtmann.org> wrote: >> >> >> >> Hi Manish, >> >> >> >> > > >> >> > > Example >> >> > > @@ -4910,3 +4911,50 @@ Controller Resume Event >> >> > > Address_Type. Otherwise, Address and Address_Type will both be zero. >> >> > > >> >> > > This event will be sent to all management sockets. >> >> > > + >> >> > > + >> >> > > +Advertisement Monitor Device Found Event >> >> > > +======================================== >> >> > > + >> >> > > + Event code: 0x002f >> >> > > + Controller Index: <controller_id> >> >> > > + Event Parameters: Monitor_Handle (2 Octets) >> >> > > + Address (6 Octets) >> >> > > + Address_Type (1 Octet) >> >> > > + >> >> > > + This event indicates that the controller has started tracking a device >> >> > > + matching an Advertisement Monitor with handle Monitor_Handle. >> >> > > + >> >> > > + The address of the device being tracked will be shared in Address and >> >> > > + Address_Type. >> >> > > + >> >> > > + Possible values for the Address_Type parameter: >> >> > > + 0 Reserved (not in use) >> >> > > + 1 LE Public >> >> > > + 2 LE Random >> >> > > + >> >> > > + This event will be sent to all management sockets. >> >> > >> >> > My initial thought was actually to include all the fields from Device Found Event here as well. So that in case we are using advertising monitor, we just need to worry about this event only. Thoughts? >> >> > The controller sends advertising reports in addition to the MSFT_Monitor_Device event. This event is reported only twice per bt-device (at start and at end of the monitoring); and it includes only the device addr and addr type [1]. To include other fields from the Device Found event, we need to buffer MSFT_Monitor_Device in the kernel and wait for the subsequent advertising report before we can send it to the bluetoothd. I feel this will unnecessarily complicate the logic in the kernel. >> >> > >> >> > This event will be used to invoke DeviceFound/Lost on the interface only when we are completely offloading monitoring to the controller (i.e. when the Sampling_Period is set to 0xFF). When the Sampling_Period is set to 0xFF, the controller sends only one advertisement report per monitoring period [2]. So, we need to rely on the MSFT_Monitor_Device controller event for RSSI and timeouts tracking. In other cases, as the bluetoothd receives more than one advertisement report, it can perform RSSI and timeouts tracking. >> >> > >> >> > So, I think it is better to pass on this event as it is to the bluetoothd and let the advertisement monitoring in the bluetoothd handle it. Let me know what you think about this? >> >> >> >> the kernel has to buffer events related to advertising reports and inquiry results already anyway. That is just the cost of business and it is the job of the kernel to do exactly that. >> >> >> >> I do not want to dumb down the kernel into a vendor extension passthrough since that is always going to come back and bite you. My current thinking is actually that unless Start Discovery triggers a discovery procedure, device that are monitored, should get its own report out path via mgmt. >> >> >> >> So the kernel would send Advertising Monitor Device Found Event (most likely with a flag for tracking started) and subsequence events of the same type whenever it gets updated. I mean, the kernel should track the state when a device is tracked anyway. It has to keep track of these things. In case of power down or reset or anything, the kernel needs to generate the Device Lost event to keeps this all in sync. Otherwise userspace is left to figure out what happens. We can not have that. This is similar to when a process dies, the kernel cleans up all open file descriptors. That is the basic paradigm that we have enforced with mgmt. If bluetoothd dies or restarts, we can get back to a state where we now all the details without having to hard reset hardware. >> >> >> >> One way to lock at this is always from the point of something that is not bluetoothd. Any other user of mgmt API needs to be sound and have a good API contract as well. Kernel APIs that are only designed with one daemon in mind are awful and cause major problems along the road. >> >> >> >> That all said, we can do this as above, but I would explore the option of doing it with my proposal and really focus on completely offload of the monitoring the controller. >> > >> > >> > Thanks for the explanation. I see your point. Based on that I’d like to propose the following changes to the bluetooth kernel and user space to take all the advantages of the controller offloading whenever available. Let me know if it sounds good? >> > >> > Existing controller behavior (based on the MSFT extension specification): >> > - Whenever the controller starts monitoring a device, it first sends the MSFT_Monitor_Device event with Monitor_State as 1 and provides the matched Monitor_Id and device address. >> > - Based on the Sampling_Period configured, it then sends one or more LE Advertisement Reports for that device during the monitoring period. >> > - Whenever the controller stops monitoring a device, it again sends the MSFT_Monitor_Device event but with Monitor_State as 0 and provides the Monitor_Id and device address of the device that was being tracked. >> > >> > Proposed kernel behavior: >> > - Upon receipt of the MSFT_Monitor_Device event with Monitor_State 1, the kernel will buffer this event until it receives the subsequent LE Advertisement Report(s). >> > - After receiving the first advertisement report for the monitored device, kernel will generate the “Adv Monitor Device Found” MGMT event which is identical to the “Device Found” MGMT event, but will have additional Monitor_Handle information for the matched monitor. >> > - A separate Device_Tracked flag is not required since this event itself indicates that the device is being tracked. >> > - If the active scanning is in progress, the existing “Device Found” event will also be generated before generating the “Adv Monitor Device Found” event. >> > - For the subsequent advertisement reports (if any) for the monitored device, if the active scanning is in progress, only the existing "Device Found" event will be generated; else, only the "Adv Monitor Device Found" event will be generated. >> > - Upon receipt of the MSFT_Monitor_Device event with Monitor_State 0, the kernel will generate the “Adv Monitor Device Lost” MGMT event with the Monitor_Handle and device address of the device that was being tracked. >> > - Also, in case of power down or reset, the kernel will generate the "Adv Monitor Device Lost" event for the monitored devices. >> > >> > Proposed user space behavior: >> > - Whenever the controller offloading is available, bluetoothd will only use the “Adv Monitor Device Found” and “Adv Monitor Device Lost” event for performing monitoring related functions and SW based filtering will be completely disabled as Monitor_Handle will be available from the kernel/controller and can be used to notify respective applications on DeviceFound/DeviceLost. >> > - Whenever the controller offloading is NOT available, bluetoothd will use the existing “Device Found” event and perform SW based filtering as it is doing right now. >> > - “Adv Monitor Device Found” event will also be used to create/update the found device when active scanning is NOT in progress. >> >> Are you still working on this or are you waiting for some feedback on >> the above, at first glance it looks proper. Btw, it would be great if >> these changes are accompanied with mgmt-tester tests since vhci has >> support for MSFT commands and we can emulate such code paths. > > > Yes, I was waiting for the feedback. I wanted to run the above proposal by you and Marcel before making the code changes. Thanks for the feedback, I'll also include the mgmt-tester tests. Great, next time just send a reminder that you are waiting for feedback since we may have just assume you had started working already, or hadn't been following the exact progress on the mailing list. Another alternative is to change the status on patchwork to something like Needs ACK so we can perhaps run some scripts that generate email or something. >> >> >> -- >> Luiz Augusto von Dentz > > Thanks, > Manish. > >
diff --git a/doc/mgmt-api.txt b/doc/mgmt-api.txt index 5355fedb0..32dd8c0f2 100644 --- a/doc/mgmt-api.txt +++ b/doc/mgmt-api.txt @@ -107,7 +107,8 @@ Configuration command, Default Runtime Configuration Changed event, Get Device Flags command, Set Device Flags command, Device Flags Changed event, Read Advertisement Monitor Features command, Add Advertisement Patterns Monitor command, Remove Advertisement Monitor command, Advertisement Monitor -Added event and Advertisement Monitor Removed event. +Added event, Advertisement Monitor Removed event, Advertisement Monitor Device +Found event and Advertisement Monitor Device Lost event. Example @@ -4910,3 +4911,50 @@ Controller Resume Event Address_Type. Otherwise, Address and Address_Type will both be zero. This event will be sent to all management sockets. + + +Advertisement Monitor Device Found Event +======================================== + + Event code: 0x002f + Controller Index: <controller_id> + Event Parameters: Monitor_Handle (2 Octets) + Address (6 Octets) + Address_Type (1 Octet) + + This event indicates that the controller has started tracking a device + matching an Advertisement Monitor with handle Monitor_Handle. + + The address of the device being tracked will be shared in Address and + Address_Type. + + Possible values for the Address_Type parameter: + 0 Reserved (not in use) + 1 LE Public + 2 LE Random + + This event will be sent to all management sockets. + + +Advertisement Monitor Device Lost Event +======================================= + + Event code: 0x0030 + Controller Index: <controller_id> + Event Parameters: Monitor_Handle (2 Octets) + Address (6 Octets) + Address_Type (1 Octet) + + This event indicates that the controller has stopped tracking a device + that was being tracked by an Advertisement Monitor with handle + Monitor_Handle. + + The address of the device being tracked will be shared in Address and + Address_Type. + + Possible values for the Address_Type parameter: + 0 Reserved (not in use) + 1 LE Public + 2 LE Random + + This event will be sent to all management sockets.