| Message ID | 20240312012053.1178140-1-pulehui@huaweicloud.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [v2] drivers/perf: riscv: Disable PERF_SAMPLE_BRANCH_* while not supported | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Tue, Mar 12, 2024 at 01:20:53AM +0000, Pu Lehui wrote: > From: Pu Lehui <pulehui@huawei.com> > > RISC-V perf driver does not yet support branch sampling. Although the > specification is in the works [0], it is best to disable such events > until support is available, otherwise we will get unexpected results. > Due to this reason, two riscv bpf testcases get_branch_snapshot and > perf_branches/perf_branches_hw fail. > > Link: https://github.com/riscv/riscv-control-transfer-records [0] > Fixes: f5bfa23f576f ("RISC-V: Add a perf core library for pmu drivers") > Signed-off-by: Pu Lehui <pulehui@huawei.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Thanks, Conor.
On Mon, Mar 11, 2024 at 6:19 PM Pu Lehui <pulehui@huaweicloud.com> wrote: > > From: Pu Lehui <pulehui@huawei.com> > > RISC-V perf driver does not yet support branch sampling. Although the > specification is in the works [0], it is best to disable such events > until support is available, otherwise we will get unexpected results. > Due to this reason, two riscv bpf testcases get_branch_snapshot and > perf_branches/perf_branches_hw fail. > > Link: https://github.com/riscv/riscv-control-transfer-records [0] > Fixes: f5bfa23f576f ("RISC-V: Add a perf core library for pmu drivers") > Signed-off-by: Pu Lehui <pulehui@huawei.com> > --- > drivers/perf/riscv_pmu.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/perf/riscv_pmu.c b/drivers/perf/riscv_pmu.c > index c78a6fd6c57f..b4efdddb2ad9 100644 > --- a/drivers/perf/riscv_pmu.c > +++ b/drivers/perf/riscv_pmu.c > @@ -313,6 +313,10 @@ static int riscv_pmu_event_init(struct perf_event *event) > u64 event_config = 0; > uint64_t cmask; > > + /* driver does not support branch stack sampling */ > + if (has_branch_stack(event)) > + return -EOPNOTSUPP; > + > hwc->flags = 0; > mapped_event = rvpmu->event_map(event, &event_config); > if (mapped_event < 0) { > -- > 2.34.1 > Reviewed-by: Atish Patra <atishp@rivosinc.com>
Hello: This patch was applied to riscv/linux.git (fixes) by Palmer Dabbelt <palmer@rivosinc.com>: On Tue, 12 Mar 2024 01:20:53 +0000 you wrote: > From: Pu Lehui <pulehui@huawei.com> > > RISC-V perf driver does not yet support branch sampling. Although the > specification is in the works [0], it is best to disable such events > until support is available, otherwise we will get unexpected results. > Due to this reason, two riscv bpf testcases get_branch_snapshot and > perf_branches/perf_branches_hw fail. > > [...] Here is the summary with links: - [v2] drivers/perf: riscv: Disable PERF_SAMPLE_BRANCH_* while not supported https://git.kernel.org/riscv/c/ea6873118493 You are awesome, thank you!
diff --git a/drivers/perf/riscv_pmu.c b/drivers/perf/riscv_pmu.c index c78a6fd6c57f..b4efdddb2ad9 100644 --- a/drivers/perf/riscv_pmu.c +++ b/drivers/perf/riscv_pmu.c @@ -313,6 +313,10 @@ static int riscv_pmu_event_init(struct perf_event *event) u64 event_config = 0; uint64_t cmask; + /* driver does not support branch stack sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + hwc->flags = 0; mapped_event = rvpmu->event_map(event, &event_config); if (mapped_event < 0) {