| Message ID | 20230512085321.13259-1-alexghiti@rivosinc.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | riscv: Allow userspace to directly access perf counters | expand |
On Fri, May 12, 2023 at 10:53:11AM +0200, Alexandre Ghiti wrote:
> base-commit-tag: v6.3
BTW Alex, in the future it'd be great if you could pick a more recent
base (eg -rc1 or riscv/for-next) so that the patchwork automation
doesn't run into a bunch of conflicts while trying to apply patches.
Cheers,
Conor.
On Fri, 12 May 2023 01:53:11 PDT (-0700), alexghiti@rivosinc.com wrote: > riscv used to allow direct access to cycle/time/instret counters, > bypassing the perf framework, this patchset intends to allow the user to > mmap any counter when accessed through perf. But we can't break the > existing behaviour so we introduce a sysctl perf_user_access like arm64 > does, which defaults to the legacy mode described above. > > *Note* that there are still ongoing discussions around which mode should > be the default mode with distro people. > > base-commit-tag: v6.3 > > Changes in v2: > - Split into smaller patches, way better! > - Add RB from Conor > - Simplify the way we checked riscv architecture > - Fix race mmap and other thread running on other cpus > - Use hwc when available > - Set all userspace access flags in event_init, too cumbersome to handle sysctl changes > - Fix arch_perf_update_userpage for pmu other than riscv-pmu by renaming pmu driver > - Fixed kernel test robot build error > - Fixed documentation (Andrew and Bagas) > - perf testsuite passes mmap tests in all 3 modes > > Alexandre Ghiti (10): > perf: Fix wrong comment about default event_idx > include: riscv: Fix wrong include guard in riscv_pmu.h > riscv: Make legacy counter enum match the HW numbering > drivers: perf: Rename riscv pmu driver > riscv: Prepare for user-space perf event mmap support > drivers: perf: Implement perf event mmap support in the legacy backend > drivers: perf: Implement perf event mmap support in the SBI backend > Documentation: admin-guide: Add riscv sysctl_perf_user_access > tools: lib: perf: Implement riscv mmap support > perf: tests: Adapt mmap-basic.c for riscv > > Documentation/admin-guide/sysctl/kernel.rst | 24 ++- > arch/riscv/kernel/Makefile | 2 +- > arch/riscv/kernel/perf_event.c | 74 ++++++++ > drivers/perf/riscv_pmu.c | 41 ++++ > drivers/perf/riscv_pmu_legacy.c | 37 +++- > drivers/perf/riscv_pmu_sbi.c | 196 +++++++++++++++++++- > include/linux/perf/riscv_pmu.h | 10 +- > include/linux/perf_event.h | 3 +- > tools/lib/perf/mmap.c | 65 +++++++ > tools/perf/tests/mmap-basic.c | 4 +- > 10 files changed, 435 insertions(+), 21 deletions(-) > create mode 100644 arch/riscv/kernel/perf_event.c It looks like there's a handful of outstanding review comments, so I'm going to mark this as changes requested in patchwork -- sorry if I missed a v3.