diff options
| author | Alexei Starovoitov <ast@kernel.org> | 2026-03-03 19:35:07 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-03-03 19:36:12 +0300 |
| commit | 74fef05ef11846515f4386d451b176ccb9e062b5 (patch) | |
| tree | ade91f9d2ca3f424da9d4f109db585845f79459f | |
| parent | 309d8808eef93d29b65ae69241a4475b2c8bd6fe (diff) | |
| parent | 0f87614c4dbdd14bbcc23c69b09be58177ce7b9b (diff) | |
| download | linux-74fef05ef11846515f4386d451b176ccb9e062b5.tar.xz | |
Merge branch 'bpf-s390-implement-get_preempt_count'
Ilya Leoshkevich says:
====================
bpf/s390: Implement get_preempt_count()
This series adds get_preempt_count() BPF implementation for s390.
On s390 preempt_count lives in lowcore: a per-cpu data structure
mapped at virtual address 0 or 0x70000 depending on the kernel
command line.
Patch 1 adds a kfunc to obtain lowcore address.
Patch 2 is the implementation that delegates to it.
====================
Link: https://patch.msgid.link/20260217160813.100855-1-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | arch/s390/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/s390/kernel/bpf.c | 12 | ||||
| -rw-r--r-- | kernel/bpf/helpers.c | 3 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_experimental.h | 11 |
4 files changed, 28 insertions, 0 deletions
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index 42c83d60d6fa..b522c6649fcc 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -80,5 +80,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_pai.o obj-$(CONFIG_TRACEPOINTS) += trace.o +obj-$(CONFIG_BPF_SYSCALL) += bpf.o + # vdso obj-y += vdso/ diff --git a/arch/s390/kernel/bpf.c b/arch/s390/kernel/bpf.c new file mode 100644 index 000000000000..713337fae626 --- /dev/null +++ b/arch/s390/kernel/bpf.c @@ -0,0 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <asm/lowcore.h> +#include <linux/btf.h> + +__bpf_kfunc_start_defs(); + +__bpf_kfunc struct lowcore *bpf_get_lowcore(void) +{ + return get_lowcore(); +} + +__bpf_kfunc_end_defs(); diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 6eb6c82ed2ee..cb6d242bd093 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -4578,6 +4578,9 @@ BTF_ID_FLAGS(func, bpf_key_put, KF_RELEASE) BTF_ID_FLAGS(func, bpf_verify_pkcs7_signature, KF_SLEEPABLE) #endif #endif +#ifdef CONFIG_S390 +BTF_ID_FLAGS(func, bpf_get_lowcore) +#endif BTF_KFUNCS_END(generic_btf_ids) static const struct btf_kfunc_id_set generic_kfunc_set = { diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index 9df77e59d4f5..44466acf8083 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -627,6 +627,10 @@ struct task_struct___preempt_rt { int softirq_disable_cnt; } __attribute__((preserve_access_index)); +#ifdef bpf_target_s390 +extern struct lowcore *bpf_get_lowcore(void) __weak __ksym; +#endif + static inline int get_preempt_count(void) { #if defined(bpf_target_x86) @@ -647,6 +651,8 @@ static inline int get_preempt_count(void) return bpf_get_current_task_btf()->thread_info.preempt.count; #elif defined(bpf_target_powerpc) return bpf_get_current_task_btf()->thread_info.preempt_count; +#elif defined(bpf_target_s390) + return bpf_get_lowcore()->preempt_count; #endif return 0; } @@ -656,6 +662,7 @@ static inline int get_preempt_count(void) * * x86 * * arm64 * * powerpc64 + * * s390x */ static inline int bpf_in_interrupt(void) { @@ -676,6 +683,7 @@ static inline int bpf_in_interrupt(void) * * x86 * * arm64 * * powerpc64 + * * s390x */ static inline int bpf_in_nmi(void) { @@ -687,6 +695,7 @@ static inline int bpf_in_nmi(void) * * x86 * * arm64 * * powerpc64 + * * s390x */ static inline int bpf_in_hardirq(void) { @@ -698,6 +707,7 @@ static inline int bpf_in_hardirq(void) * * x86 * * arm64 * * powerpc64 + * * s390x */ static inline int bpf_in_serving_softirq(void) { @@ -717,6 +727,7 @@ static inline int bpf_in_serving_softirq(void) * * x86 * * arm64 * * powerpc64 + * * s390x */ static inline int bpf_in_task(void) { |