[FFmpeg-devel] [PATCHv3 0/6] RISC-V Linux perf run-time enablement

Rémi Denis-Courmont remi at remlab.net
Wed Jul 19 22:55:02 EEST 2023


	Hello,

This allows run-time fallback from Linux (or MacOS k)perf to the raw
cycle counter. The main purpose is to deal with RISC-V's hard
deprecation of RDCYCLE access from userspace, all the while preserving
compatibility with existing kernels which do not support Linux perf.
This is also usable as a baseline to fallback further to another
counter, presumably RDTIME (and Arm's equivalent).

Main change since version 2 is retaining inline AV_READ_TIME in
configuration where AV_READ_TIME was/is used.

----------------------------------------------------------------
Rémi Denis-Courmont (6):
      checkasm: make perf macros functional
      checkasm: use pointers for start/stop functions
      checkasm: remove unused variables
      checkasm: make bench clean-up also a function pointer
      checkasm: allow run-time fallback to AV_READ_TIME
      configure: enable Linux perf on RISC-V by default

 configure                 |  2 +-
 tests/checkasm/checkasm.c | 99 +++++++++++++++++++++++++++++++++--------------
 tests/checkasm/checkasm.h | 50 +++++++-----------------
 3 files changed, 85 insertions(+), 66 deletions(-)

-- 
雷米‧德尼-库尔蒙
http://www.remlab.net/





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