On 19 September 2017 at 17:26, Kim Phillips kim.phillips@arm.com wrote:
On Tue, 19 Sep 2017 03:33:16 -0500 Tor Jeremiassen tor@ti.com wrote:
This patchset adds support for user space decoding of CoreSight traces [1]
These [x] references don't exist at the bottom of this email: did you forget to add them?
of the ARM architecture. Kernel support for configuring CoreSight tracers and collect the hardware trace data in the auxtrace section of the perf.data file is already integrated [2]. The user space implementation mirrors to a large degree that of the Intel Processor Trace (PT) [3] implementation, except that the decoder library itself is separate from the perf tool sources, and is built and maintained as a separate open source project [4]. Instead, this patch set includes the necessary code and build settings to interfaces to the decoder library, as well as a "stub" or "null" library for the case when the perf tool is built without the library.
I seriously doubt this would be acceptable upstream: they prefer to have all code fully-inclusive.
I have a different opinion. The perf tools can be compile with or without the library and it is not mandatory that it is included in the kernel tree.
Do we have a plan for somehow upstreaming the library, or some other means for working around this restriction?
As per our conversation in Los Angeles, we currently do not have a plan to push the openCSD library to the kernel tree.
The decoder library interface code in this patch set only supports ETMv4 trace decoding, though the library itself supports a broader range. Future patches will add support for more versions of the ARM ETM trace encoding.
Changes from v2:
I haven't seen any prior versions submitted to this list; should this per-version change info be stripped, given according to the people on this list, it's the first version we're seeing?
It would be nice to know what branch of what tree this series is supposed to be applied to, or even have a URL for a git repo where they've been already suitably applied? I see one of the OpenCSD forks on github is owned by user Tor: Can they be pushed there for easy access?
Thanks,
Kim