diff options
| author | Pu Lehui <pulehui@huawei.com> | 2024-03-12 01:20:53 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-03-26 14:09:18 -0700 |
| commit | ea6873118493019474abbf57d5a800da365734df (patch) | |
| tree | e9f7091a893941b07b47c536ff37bcc58a43ce1a | |
| parent | 4b0bf9a0127029054c2fa18ba5b3f3ddc45f54ed (diff) | |
drivers/perf: riscv: Disable PERF_SAMPLE_BRANCH_* while not supported
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: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240312012053.1178140-1-pulehui@huaweicloud.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| -rw-r--r-- | drivers/perf/riscv_pmu.c | 4 |
1 files changed, 4 insertions, 0 deletions
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) { |