diff options
Diffstat (limited to 'tools/testing/selftests/bpf/bpf_experimental.h')
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_experimental.h | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index da7e230f2781..d89eda3fd8a3 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -599,4 +599,58 @@ extern void bpf_iter_dmabuf_destroy(struct bpf_iter_dmabuf *it) __weak __ksym; extern int bpf_cgroup_read_xattr(struct cgroup *cgroup, const char *name__str, struct bpf_dynptr *value_p) __weak __ksym; +#define PREEMPT_BITS 8 +#define SOFTIRQ_BITS 8 +#define HARDIRQ_BITS 4 +#define NMI_BITS 4 + +#define PREEMPT_SHIFT 0 +#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS) +#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS) +#define NMI_SHIFT (HARDIRQ_SHIFT + HARDIRQ_BITS) + +#define __IRQ_MASK(x) ((1UL << (x))-1) + +#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT) +#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT) +#define NMI_MASK (__IRQ_MASK(NMI_BITS) << NMI_SHIFT) + +extern bool CONFIG_PREEMPT_RT __kconfig __weak; +#ifdef bpf_target_x86 +extern const int __preempt_count __ksym; +#endif + +struct task_struct___preempt_rt { + int softirq_disable_cnt; +} __attribute__((preserve_access_index)); + +static inline int get_preempt_count(void) +{ +#if defined(bpf_target_x86) + return *(int *) bpf_this_cpu_ptr(&__preempt_count); +#elif defined(bpf_target_arm64) + return bpf_get_current_task_btf()->thread_info.preempt.count; +#endif + return 0; +} + +/* Description + * Report whether it is in interrupt context. Only works on the following archs: + * * x86 + * * arm64 + */ +static inline int bpf_in_interrupt(void) +{ + struct task_struct___preempt_rt *tsk; + int pcnt; + + pcnt = get_preempt_count(); + if (!CONFIG_PREEMPT_RT) + return pcnt & (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_MASK); + + tsk = (void *) bpf_get_current_task_btf(); + return (pcnt & (NMI_MASK | HARDIRQ_MASK)) | + (tsk->softirq_disable_cnt & SOFTIRQ_MASK); +} + #endif |