Re: [PATCH v7 0/8] perf cs-etm: Add support for sample flags

[Mathieu Poirier]

On Tue, 29 Jan 2019 at 05:29, 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 set is applied on the acme's perf core branch with the latest
> commit bdec77cfe58d ("Merge remote-tracking branch 'tip/perf/urgent'
> into perf/core").
>
> This patch set has been verified for x86 and arm64 perf building and
> also is verified with below command:
>
> Before:
>
>   # perf script -F,-time,+flags -k vmlinux
>
>   [...]
>
>   main  6650 [001]          1              branches:                                f7b08490 lib_loop_test+0xc (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                f7b084b0 lib_loop_test+0x2c (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:                                  6b65a8 main+0x1c (/root/coresight_test/main)
>   main  6650 [001]          1              branches:                                  6b6448 printf@plt+0x8 (/root/coresight_test/main)
>   main  6650 [001]          1              branches:                                  6b642c _init+0x18 (/root/coresight_test/main)
>   main  6650 [001]          1              branches:                                f7b2d23c [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2906e [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b255ee [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:                                f7b25634 [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>
>   [...]
>
>
> After:
>
>   # perf script -F,-time,+flags -k vmlinux
>
>   [...]
>
>   main  6650 [001]          1              branches:   jmp                          f7b08490 lib_loop_test+0xc (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   jcc                          f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   jcc                          f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   jcc                          f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   jcc                          f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   jcc                          f7b084a2 lib_loop_test+0x1e (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   return                       f7b084b0 lib_loop_test+0x2c (/root/coresight_test/libcstest.so)
>   main  6650 [001]          1              branches:   call                           6b65a8 main+0x1c (/root/coresight_test/main)
>   main  6650 [001]          1              branches:   return                         6b6448 printf@plt+0x8 (/root/coresight_test/main)
>   main  6650 [001]          1              branches:   return                         6b642c _init+0x18 (/root/coresight_test/main)
>   main  6650 [001]          1              branches:   call                         f7b2d23c [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   call                         f7b2906e [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jcc                          f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jcc                          f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jcc                          f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jcc                          f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jcc                          f7b2559a [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   jmp                          f7b255ee [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>   main  6650 [001]          1              branches:   call                         f7b25634 [unknown] (/usr/lib/arm-linux-gnueabihf/ld-2.27.so)
>
>   [...]

Good day Arnaldo,

I have reviewed, compiled and tested this patchset - please consider
for inclusion.

Regards,
Mathieu

>
>
> Changes from v6:
> * Addressed Mathieu's suggestion for patch 0005, refined its commit log
>   and comment and fixed cs_etm__get_cpu() definitions in header file;
>   also tested with perf for Arm and x86 buildings.
> * Added Mathieu's review tags.
>
> 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                      | 394 +++++++++++++++++-
>  tools/perf/util/cs-etm.h                      |  53 ++-
>  4 files changed, 476 insertions(+), 18 deletions(-)
>
> --
> 2.17.1
>