Currently, there is no RISC-V support for get_preempt_count() and its fallback path always returns 0. Add it so that bpf_in_interrupt(), bpf_in_nmi(), bpf_in_hardirq(), bpf_in_serving_softirq(), and bpf_in_task() work for RISC-V as well. Given that RISC-V has supported CONFIG_THREAD_INFO_IN_TASK since its initial commit fbe934d69eb7 ("RISC-V: Build Infrastructure") in 2017, directly retrieve preempt_count from the thread_info embedded within task_struct via bpf_get_current_task_btf(). This aligns the implementation with arm64, powerpc, and loongarch. Tested on a RISC-V virtual machine. Before: $ sudo ./test_progs -t exe_ctx ... #114 exe_ctx:FAIL Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED After: $ sudo ./test_progs -t exe_ctx #114 exe_ctx:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Tiezhu Yang Tested-by: Pu Lehui Reviewed-by: Pu Lehui --- RFC -> v1: -- No code changes -- Update the commit message -- Add Tested-by and Reviewed-by https://lore.kernel.org/bpf/0191fe3f-b956-480d-aef2-a4d75f9e02de@huawei.com/ tools/testing/selftests/bpf/bpf_experimental.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index 67ff7882299e..ff37ae5a113d 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -425,6 +425,8 @@ static inline int get_preempt_count(void) return bpf_get_lowcore()->preempt_count; #elif defined(bpf_target_loongarch) return bpf_get_current_task_btf()->thread_info.preempt_count; +#elif defined(bpf_target_riscv) + return bpf_get_current_task_btf()->thread_info.preempt_count; #endif return 0; } @@ -436,6 +438,7 @@ static inline int get_preempt_count(void) * * powerpc64 * * s390x * * loongarch + * * riscv */ static inline int bpf_in_interrupt(void) { @@ -458,6 +461,7 @@ static inline int bpf_in_interrupt(void) * * powerpc64 * * s390x * * loongarch + * * riscv */ static inline int bpf_in_nmi(void) { @@ -471,6 +475,7 @@ static inline int bpf_in_nmi(void) * * powerpc64 * * s390x * * loongarch + * * riscv */ static inline int bpf_in_hardirq(void) { @@ -484,6 +489,7 @@ static inline int bpf_in_hardirq(void) * * powerpc64 * * s390x * * loongarch + * * riscv */ static inline int bpf_in_serving_softirq(void) { @@ -505,6 +511,7 @@ static inline int bpf_in_serving_softirq(void) * * powerpc64 * * s390x * * loongarch + * * riscv */ static inline int bpf_in_task(void) { -- 2.42.0