From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by lists.ozlabs.org (Postfix) with ESMTP id ACE511A04B7 for ; Fri, 13 Mar 2015 07:37:15 +1100 (AEDT) Date: Thu, 12 Mar 2015 17:37:11 -0300 From: Arnaldo Carvalho de Melo To: "Naveen N. Rao" Subject: Re: [PATCHv2 8/8] perf probe powerpc: Fixup function entry if using kallsyms lookup Message-ID: <20150312203711.GI3550@kernel.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Em Mon, Dec 15, 2014 at 08:20:38PM +0530, Naveen N. Rao escreveu: > On powerpc ABIv2, if no debug-info is found and we use kallsyms, we need > to fixup the function entry to point to the local entry point. Use > offset of 8 since current toolchains always generate 2 instructions (8 > bytes). So perhaps we should rename ARCH_SYMBOL_HANDLING to ARCH_ABI_SYMBOL_FIXUPS? > Signed-off-by: Naveen N. Rao > --- > Changes: > Generalize and introduce helper to post-process trace point. > > tools/perf/arch/powerpc/util/sym-handling.c | 17 +++++++++++++++++ > tools/perf/util/probe-event.c | 1 + > tools/perf/util/probe-event.h | 10 ++++++++++ > 3 files changed, 28 insertions(+) > > diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c > index 22fc2e6..30c8797 100644 > --- a/tools/perf/arch/powerpc/util/sym-handling.c > +++ b/tools/perf/arch/powerpc/util/sym-handling.c > @@ -45,3 +45,20 @@ inline bool prefer_symtab(void) > return false; > #endif > } > + > +void arch_fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, > + struct probe_trace_event *tev __maybe_unused, > + struct map *map __maybe_unused) > +{ > +#if defined(_CALL_ELF) && _CALL_ELF == 2 > + /* > + * If we used kallsyms, we should fixup the function entry address here. > + * ppc64 ABIv2 local entry point is currently always 2 instructions (8 bytes) > + * after the global entry point. Fix this if it ever changes. > + */ > + if (!pev->uprobes && map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) { > + tev->point.address += 8; > + tev->point.offset += 8; > + } > +#endif > +} > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index dfc3151..85f37a4 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -2340,6 +2340,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, > strdup_or_goto(pev->args[i].type, > nomem_out); > } > + arch_fix_tev_from_maps(pev, tev, map); > } > > out: > diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h > index 5f92906..335a6a4 100644 > --- a/tools/perf/util/probe-event.h > +++ b/tools/perf/util/probe-event.h > @@ -147,6 +147,16 @@ extern bool prefer_symtab(void); > static inline bool prefer_symtab(void) { return false; }; > #endif > > +#ifdef HAVE_ARCH_SYMBOL_HANDLING > +extern void arch_fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, > + struct probe_trace_event *tev __maybe_unused, > + struct map *map __maybe_unused); > +#else > +static inline void arch_fix_tev_from_maps(struct perf_probe_event *pev __maybe_unused, > + struct probe_trace_event *tev __maybe_unused, > + struct map *map __maybe_unused) { } > +#endif > + > /* Maximum index number of event-name postfix */ > #define MAX_EVENT_INDEX 1024 > > -- > 2.1.3