diff options
Diffstat (limited to 'tools/lib/bpf')
| -rw-r--r-- | tools/lib/bpf/bpf_core_read.h | 16 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 6 |
2 files changed, 16 insertions, 6 deletions
diff --git a/tools/lib/bpf/bpf_core_read.h b/tools/lib/bpf/bpf_core_read.h index 53b3e199fb25..09ebe3db5f2f 100644 --- a/tools/lib/bpf/bpf_core_read.h +++ b/tools/lib/bpf/bpf_core_read.h @@ -88,11 +88,19 @@ enum bpf_enum_value_kind { const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \ unsigned long long val; \ \ + /* This is a so-called barrier_var() operation that makes specified \ + * variable "a black box" for optimizing compiler. \ + * It forces compiler to perform BYTE_OFFSET relocation on p and use \ + * its calculated value in the switch below, instead of applying \ + * the same relocation 4 times for each individual memory load. \ + */ \ + asm volatile("" : "=r"(p) : "0"(p)); \ + \ switch (__CORE_RELO(s, field, BYTE_SIZE)) { \ - case 1: val = *(const unsigned char *)p; \ - case 2: val = *(const unsigned short *)p; \ - case 4: val = *(const unsigned int *)p; \ - case 8: val = *(const unsigned long long *)p; \ + case 1: val = *(const unsigned char *)p; break; \ + case 2: val = *(const unsigned short *)p; break; \ + case 4: val = *(const unsigned int *)p; break; \ + case 8: val = *(const unsigned long long *)p; break; \ } \ val <<= __CORE_RELO(s, field, LSHIFT_U64); \ if (__CORE_RELO(s, field, SIGNED)) \ diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a1cddd17af7d..e2a3cf437814 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -5115,6 +5115,7 @@ err_out: * least one of enums should be anonymous; * - for ENUMs, check sizes, names are ignored; * - for INT, size and signedness are ignored; + * - any two FLOATs are always compatible; * - for ARRAY, dimensionality is ignored, element types are checked for * compatibility recursively; * - everything else shouldn't be ever a target of relocation. @@ -5141,6 +5142,7 @@ recur: switch (btf_kind(local_type)) { case BTF_KIND_PTR: + case BTF_KIND_FLOAT: return 1; case BTF_KIND_FWD: case BTF_KIND_ENUM: { @@ -6245,8 +6247,8 @@ patch_insn: /* bpf_core_patch_insn() should know how to handle missing targ_spec */ err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res); if (err) { - pr_warn("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n", - prog->name, relo_idx, relo->insn_off, err); + pr_warn("prog '%s': relo #%d: failed to patch insn #%zu: %d\n", + prog->name, relo_idx, relo->insn_off / BPF_INSN_SZ, err); return -EINVAL; } |