diff options
Diffstat (limited to 'tools/lib')
| -rw-r--r-- | tools/lib/bpf/bpf_core_read.h | 27 |
1 files changed, 11 insertions, 16 deletions
diff --git a/tools/lib/bpf/bpf_core_read.h b/tools/lib/bpf/bpf_core_read.h index 11461b2623b0..7009dc90e012 100644 --- a/tools/lib/bpf/bpf_core_read.h +++ b/tools/lib/bpf/bpf_core_read.h @@ -39,32 +39,27 @@ enum bpf_field_info_kind { #endif /* - * Extract bitfield, identified by src->field, and put its value into u64 - * *res. All this is done in relocatable manner, so bitfield changes such as + * Extract bitfield, identified by s->field, and return its value as u64. + * All this is done in relocatable manner, so bitfield changes such as * signedness, bit size, offset changes, this will be handled automatically. * This version of macro is using bpf_probe_read() to read underlying integer * storage. Macro functions as an expression and its return type is * bpf_probe_read()'s return value: 0, on success, <0 on error. */ -#define BPF_CORE_READ_BITFIELD_PROBED(src, field, res) ({ \ - unsigned long long val; \ +#define BPF_CORE_READ_BITFIELD_PROBED(s, field) ({ \ + unsigned long long val = 0; \ \ - *res = 0; \ - val = __CORE_BITFIELD_PROBE_READ(res, src, field); \ - if (!val) { \ - *res <<= __CORE_RELO(src, field, LSHIFT_U64); \ - val = __CORE_RELO(src, field, RSHIFT_U64); \ - if (__CORE_RELO(src, field, SIGNED)) \ - *res = ((long long)*res) >> val; \ - else \ - *res = ((unsigned long long)*res) >> val; \ - val = 0; \ - } \ + __CORE_BITFIELD_PROBE_READ(&val, s, field); \ + val <<= __CORE_RELO(s, field, LSHIFT_U64); \ + if (__CORE_RELO(s, field, SIGNED)) \ + val = ((long long)val) >> __CORE_RELO(s, field, RSHIFT_U64); \ + else \ + val = val >> __CORE_RELO(s, field, RSHIFT_U64); \ val; \ }) /* - * Extract bitfield, identified by src->field, and return its value as u64. + * Extract bitfield, identified by s->field, and return its value as u64. * This version of macro is using direct memory reads and should be used from * BPF program types that support such functionality (e.g., typed raw * tracepoints). |