[PATCH 1/5] serial: imx: remove unneeded imx_transmit_buffer() from imx_start_tx()

Huang Shijie b32955 at freescale.com
Mon May 12 01:17:16 PDT 2014

于 2014年05月12日 16:03, Dean Jenkins 写道:
> Well, the locking might now be OK but due to an existing issue the TX 
> will be woken up excessively with no new characters to transmit so 
> there will be excessive context switching with the new work queue that 
> results in no useful work done. There is an API issue in HCI LDISC 
> because TTY_DO_WRITE_WAKEUP is set BEFORE checking whether any 
> characters remain pending to be sent. This means most of the time 
> hci_uart_tx_wakeup() is unnecessarily called will no chance of seeing 
> any remain pending characters to be process. This weakness contributed 
> to triggering lockup issue.
You can send a patch to fix the Bluetooth code. :)
I am happy if you can improve the Bluetooth.

Huang Shijie

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