Re: [PATCH v3 0/4] Bluetooth: Improve retrying of connection attempts

From: Jonas Dreßler
Date: Tue Jan 09 2024 - 16:58:15 EST


Hi Luiz,

On 1/9/24 18:53, Luiz Augusto von Dentz wrote:
Hi Jonas,

On Mon, Jan 8, 2024 at 5:46 PM Jonas Dreßler <verdre@xxxxxxx> wrote:

Since commit 4c67bc74f016 ("[Bluetooth] Support concurrent connect
requests"), the kernel supports trying to connect again in case the
bluetooth card is busy and fails to connect.

The logic that should handle this became a bit spotty over time, and also
cards these days appear to fail with more errors than just "Command
Disallowed".

This series refactores the handling of concurrent connection requests
by serializing all "Create Connection" commands for ACL connections
similar to how we do it for LE connections.

---

v1: https://lore.kernel.org/linux-bluetooth/20240102185933.64179-1-verdre@xxxxxxx/
v2: https://lore.kernel.org/linux-bluetooth/20240108183938.468426-1-verdre@xxxxxxx/
v3:
- Move the new sync function to hci_sync.c as requested by review
- Abort connection on failure using hci_abort_conn_sync() instead of
hci_abort_conn()
- Make the last commit message a bit more precise regarding the meaning
of BT_CONNECT2 state

Jonas Dreßler (4):
Bluetooth: Remove superfluous call to hci_conn_check_pending()
Bluetooth: hci_event: Use HCI error defines instead of magic values
Bluetooth: hci_conn: Only do ACL connections sequentially
Bluetooth: Remove pending ACL connection attempts

include/net/bluetooth/hci.h | 3 ++
include/net/bluetooth/hci_core.h | 1 -
include/net/bluetooth/hci_sync.h | 3 ++
net/bluetooth/hci_conn.c | 83 +++-----------------------------
net/bluetooth/hci_event.c | 29 +++--------
net/bluetooth/hci_sync.c | 72 +++++++++++++++++++++++++++
6 files changed, 93 insertions(+), 98 deletions(-)

--
2.43.0

After rebasing and fixing a little bit here and there, see v4, looks
like this changes is affecting the following mgmt-tester -s "Pair
Device - Power off 1":

Pair Device - Power off 1 - init
Read Version callback
Status: Success (0x00)
Version 1.22
Read Commands callback
Status: Success (0x00)
Read Index List callback
Status: Success (0x00)
Index Added callback
Index: 0x0000
Enable management Mesh interface
Enabling Mesh feature
Read Info callback
Status: Success (0x00)
Address: 00:AA:01:00:00:00
Version: 0x09
Manufacturer: 0x05f1
Supported settings: 0x0001bfff
Current settings: 0x00000080
Class: 0x000000
Name:
Short name:
Mesh feature is enabled
Pair Device - Power off 1 - setup
Setup sending Set Bondable (0x0009)
Setup sending Set Powered (0x0005)
Initial settings completed
Test setup condition added, total 1
Client set connectable: Success (0x00)
Test setup condition complete, 0 left
Pair Device - Power off 1 - setup complete
Pair Device - Power off 1 - run
Sending Pair Device (0x0019)
Bluetooth: hci0: command 0x0405 tx timeout
Bluetooth: hci0: command 0x0408 tx timeout
Test condition added, total 1
Pair Device - Power off 1 - test timed out
Pair Device (0x0019): Disconnected (0x0e)
Pair Device - Power off 1 - test not run
Pair Device - Power off 1 - teardown
Pair Device - Power off 1 - teardown
Index Removed callback
Index: 0x0000
Pair Device - Power off 1 - teardown complete
Pair Device - Power off 1 - done


Thanks for landing the first two commits!

I think this is actually the same issue causing the test failure
as in the other issue I had:
https://lore.kernel.org/linux-bluetooth/7cee4e74-3a0c-4b7c-9984-696e646160f8@xxxxxxx/

It seems that the emulator is unable to reply to HCI commands sent
from the hci_sync machinery, possibly because that is sending things
on a separate thread?

Cheers,
Jonas