Re: [PATCH v6 0/8] perf cs-etm: Add support for sample flags

From: Mathieu Poirier
Date: Wed Jan 23 2019 - 19:22:18 EST


On Fri, 18 Jan 2019 at 18:44, Leo Yan <leo.yan@xxxxxxxxxx> wrote:
>
> This patch seris adds support for sample flags so can facilitate perf
> to print sample flags for branch instruction.
>
> Patch 0001 is used to save last branch information in packet structure,
> this includes instruction type, subtype and condition flag to help
> making decision for which branch instruction it is. It passes related
> information from decoder layer to cs-etm.c, so we use cs-etm.c as a
> central place to set sample flags.
>
> Patch 0002 is used to set sample flags for instruction range packet.
>
> Patch 0003 is used to set sample flags for trace discontinuity packet.
>
> Patches 0004/0005/0006 are preparation for exception packet handling:
> Patch 0004 addes exception number in packet; pacth 0005/0006 is to use
> traceID/metadata tuple to access metadata pointer based on traceID, this
> can help decide if the CPU is connected with ETMv3 or ETMv4, ETMv3 and
> ETMv4 have totally different definition for exception numbers.
>
> Patch 0007 sets sample flags for exception packet; patch 0008 support
> sample flags for exception return packet.
>
> This patch series is applied on the acme's perf core branch with the
> with latest commit 02bb912ae451 ("perf tools: Replace automatic const
> char[] variables by statics").
>
> After applying this patch series, we can verify sample flags with below
> command:
>
> # perf script -F,-time,+flags,+ip,+sym,+dso,+addr,+symoff -k vmlinux

Since you are going for another iteration please add a "before" and
"after" example.

Thanks,
Mathieu


>
> Changes from v5:
> * Addressed Rob's suggestion to add specification info for exception
> number encoding;
> * Added Rob's review tag in patch 0007.
>
> Changes from v4:
> * Fixed typos in comments, and removed redundant info from commit log;
> * Addressed Mathieu's suggestion to add helper functions for metadata
> fields (CS_ETM_CPU and CS_ETM_MAGIC) accessing;
> * Addressed Mathieu's suggestion to include headers with alphabetical
> order.
>
> Changes from v3:
> * Fixed typos in commit logs;
> * Rearranged fields in cs_etm_packet by grouping with same variable
> types;
> * Fixed ETMv4 exception number which pointed by Mike;
> * Fixed ETMv4 SVC / SMC / HVC in the same CALL, by checking svc
> instruction to distinguish them;
> * Refine ETMv4 return exception packet handling.
>
> Changes from v2:
> * Addressed Mathieu's suggestion to split one big patch to 3 small
> patches for setting sample flags, one is for instruction range
> packet, one is for discontinuity packet and one is for exception
> packet.
> * Added supporting for ETMv3 exception packet.
> * Followed Mathieu's suggestion to move all sample flags handling
> from decoder layer to cs-etm.c, thus it has enough info to set flags
> based on trace context in single place.
>
> Changes from v1:
> * Moved exception packets handling patches into patch series 'perf
> cs-etm: Correct packets handling'.
> * Added sample flags fixing up for TRACE_OFF packet.
> * Created a new function which is used to maintain flags fixing up.
>
>
> Leo Yan (8):
> perf cs-etm: Add last instruction information in packet
> perf cs-etm: Set sample flags for instruction range packet
> perf cs-etm: Set sample flags for trace discontinuity
> perf cs-etm: Add exception number in exception packet
> perf cs-etm: Change tuple from traceID-CPU# to traceID-metadata
> perf cs-etm: Add traceID in packet
> perf cs-etm: Set sample flags for exception packet
> perf cs-etm: Set sample flags for exception return packet
>
> .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 41 +-
> .../perf/util/cs-etm-decoder/cs-etm-decoder.h | 6 +
> tools/perf/util/cs-etm.c | 405 +++++++++++++++++-
> tools/perf/util/cs-etm.h | 48 ++-
> 4 files changed, 482 insertions(+), 18 deletions(-)
>
> --
> 2.17.1
>