Unverified Commit 4d631928 authored by Haibo Xu's avatar Haibo Xu Committed by Palmer Dabbelt
Browse files

perf symbols: Ignore mapping symbols on riscv 

RISCV ELF use mapping symbols with special names $x, $d to
identify regions of RISCV code or code with different ISAs[1].
These symbols don't identify functions, so will confuse the
perf output.

The patch filters out these symbols at load time, similar to
"4886f2ca perf symbols: Ignore mapping symbols on aarch64".

[1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/


    master/riscv-elf.adoc#mapping-symbol

Signed-off-by: default avatarHaibo Xu <haibo1.xu@intel.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250409025202.201046-1-haibo1.xu@intel.com


Signed-off-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: default avatarPalmer Dabbelt <palmer@dabbelt.com>
parent 9eb9ea31

tools/perf/util/symbol-elf.c

+6 −0
Original line number Diff line number Diff line
@@ -1733,6 +1733,12 @@ dso__load_sym_internal(struct dso *dso, struct map *map, struct symsrc *syms_ss, 
				continue;

		}



		/* Reject RISCV ELF "mapping symbols" */

		if (ehdr.e_machine == EM_RISCV) {

			if (elf_name[0] == '$' && strchr("dx", elf_name[1]))

				continue;

		}



		if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) {

			u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr;

			u64 *opd = opddata->d_buf + offset;