On Wed, 8 Mar 2017 13:56:10 +0530 "Naveen N. Rao" <naveen.n....@linux.vnet.ibm.com> wrote:
> perf now uses an offset from _text/_stext for kretprobes if the kernel > supports it, rather than the actual function name. As such, let's choose > the LEP for powerpc ABIv2 so as to ensure the probe gets hit. Do it only > if the kernel supports specifying offsets with kretprobes. Acked-by: Masami Hiramatsu <mhira...@kernel.org> This patch is OK. And I found that most of functions in sym-handling.c are used only when libelf is supported. (e.g. probe-event.c itself is not built when we have no libelf) So, for the next cleanup, this file should not be compiled without libelf. Thanks! > > Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com> > --- > tools/perf/arch/powerpc/util/sym-handling.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/tools/perf/arch/powerpc/util/sym-handling.c > b/tools/perf/arch/powerpc/util/sym-handling.c > index 1030a6e504bb..39dbe512b9fc 100644 > --- a/tools/perf/arch/powerpc/util/sym-handling.c > +++ b/tools/perf/arch/powerpc/util/sym-handling.c > @@ -10,6 +10,7 @@ > #include "symbol.h" > #include "map.h" > #include "probe-event.h" > +#include "probe-file.h" > > #ifdef HAVE_LIBELF_SUPPORT > bool elf__needs_adjust_symbols(GElf_Ehdr ehdr) > @@ -79,13 +80,18 @@ void arch__fix_tev_from_maps(struct perf_probe_event *pev, > * However, if the user specifies an offset, we fall back to using the > * GEP since all userspace applications (objdump/readelf) show function > * disassembly with offsets from the GEP. > - * > - * In addition, we shouldn't specify an offset for kretprobes. > */ > - if (pev->point.offset || (!pev->uprobes && pev->point.retprobe) || > - !map || !sym) > + if (pev->point.offset || !map || !sym) > return; > > + /* For kretprobes, add an offset only if the kernel supports it */ > + if (!pev->uprobes && pev->point.retprobe) { > +#ifdef HAVE_LIBELF_SUPPORT > + if (!kretprobe_offset_is_supported()) > +#endif > + return; > + } > + > lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym); > > if (map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) > -- > 2.11.1 > -- Masami Hiramatsu <mhira...@kernel.org>