Re: [PATCH v3 1/1] binder: transaction latency tracking for user build

[Greg Kroah-Hartman]

On Thu, Apr 30, 2020 at 04:13:59PM +0800, Frankie Chang wrote:
> Record start/end timestamp for binder transaction.
> When transaction is completed or transaction is free,
> it would be checked if transaction latency over threshold (2 sec),
> if yes, printing related information for tracing.
> 
> /* Implement details */
> - Add tracepoint/trace at free transaction.
>   Since the original trace_binder_transaction_received cannot
>   precisely present the real finished time of transaction, adding a
>   trace_binder_free_transaction at the point of free transaction
>   may be more close to it.
> 
> - Add latency tracer module to monitor slow transaction.
>   The trace_binder_free_transaction would not be enabled
>   by default. Monitoring which transaction is too slow to
>   cause some of exceptions is important. So we hook the
>   tracepoint to call the monitor function.
> 
> - Move some struct from core file to header file.
>   Need some struct defined in core file in latency trace module
>   In addition, moving all structs to header file makes module
>   more extendable, and make all these strcuts to be defined
>   in the same file.

Also, this should be split up into a patch series, the first moving
things around, and the rest of the patches each adding a single feature.
As it is, this patch is almost impossible to review.

thanks,

greg k-h