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| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2016-04-12 14:40:50 +0530 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-05-05 21:04:03 -0300 |
| commit | 0b3c2264ae30ed692fd1ffd2b84c5fbdf737cb0d (patch) | |
| tree | f26cae86be020c92c2a78880da9af369427f3456 /tools/perf/util/symbol-elf.c | |
| parent | 239aeba764092b29dd7cab177cd47f472390622e (diff) | |
| download | lwn-0b3c2264ae30ed692fd1ffd2b84c5fbdf737cb0d.tar.gz lwn-0b3c2264ae30ed692fd1ffd2b84c5fbdf737cb0d.zip | |
perf symbols: Fix kallsyms perf test on ppc64le
ppc64le functions have a Global Entry Point (GEP) and a Local Entry
Point (LEP). While placing a probe, we always prefer the LEP since it
catches function calls through both the GEP and the LEP. In order to do
this, we fixup the function entry points during elf symbol table lookup
to point to the LEPs. This works, but breaks 'perf test kallsyms' since
the symbols loaded from the symbol table (pointing to the LEP) do not
match the symbols in kallsyms.
To fix this, we do not adjust all the symbols during symbol table load.
Instead, we note down st_other in a newly introduced arch-specific
member of perf symbol structure, and later use this to adjust the probe
trace point.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/6be7c2b17e370100c2f79dd444509df7929bdd3e.1460451721.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/symbol-elf.c')
| -rw-r--r-- | tools/perf/util/symbol-elf.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 3f9d6798bd18..87a297dd8901 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -770,7 +770,8 @@ static bool want_demangle(bool is_kernel_sym) return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle; } -void __weak arch__elf_sym_adjust(GElf_Sym *sym __maybe_unused) { } +void __weak arch__sym_update(struct symbol *s __maybe_unused, + GElf_Sym *sym __maybe_unused) { } int dso__load_sym(struct dso *dso, struct map *map, struct symsrc *syms_ss, struct symsrc *runtime_ss, @@ -947,8 +948,6 @@ int dso__load_sym(struct dso *dso, struct map *map, (sym.st_value & 1)) --sym.st_value; - arch__elf_sym_adjust(&sym); - if (dso->kernel || kmodule) { char dso_name[PATH_MAX]; @@ -1082,6 +1081,8 @@ new_symbol: if (!f) goto out_elf_end; + arch__sym_update(f, &sym); + if (filter && filter(curr_map, f)) symbol__delete(f); else { |