Em Tue, Apr 28, 2015 at 05:35:35PM +0530, Naveen N. Rao escreveu:
> If using the symbol table, symbol addresses are not being fixed up
> properly, resulting in probes being placed at wrong addresses:
>
> # perf probe do_fork
> Added new event:
> probe:do_fork (on do_fork)
>
> You can now use it in all perf tools, such as:
>
> perf record -e probe:do_fork -aR sleep 1
>
> # cat /sys/kernel/debug/tracing/kprobe_events
> p:probe/do_fork _text+635952
> # printf "%x" 635952
> 9b430
> # grep do_fork /boot/System.map
> c0000000000ab430 T .do_fork
>
> Fix by checking for ELF type ET_DYN used by ppc64 kernels.
>
> Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
> Reviewed-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com>
This one looks great, Are you keeping the Reviewed by from a previous
patch? Or has Srikar reissued it? Srikar?
- Arnaldo
> ---
> Changes:
> - Introduce arch helper to limit change to ppc.
>
> tools/perf/arch/powerpc/util/Build | 1 +
> tools/perf/arch/powerpc/util/sym-handling.c | 19 +++++++++++++++++++
> tools/perf/util/symbol-elf.c | 8 ++++++--
> tools/perf/util/symbol.h | 4 ++++
> 4 files changed, 30 insertions(+), 2 deletions(-)
> create mode 100644 tools/perf/arch/powerpc/util/sym-handling.c
>
> diff --git a/tools/perf/arch/powerpc/util/Build
> b/tools/perf/arch/powerpc/util/Build
> index 0af6e9b..7b8b0d1 100644
> --- a/tools/perf/arch/powerpc/util/Build
> +++ b/tools/perf/arch/powerpc/util/Build
> @@ -1,4 +1,5 @@
> libperf-y += header.o
> +libperf-y += sym-handling.o
>
> libperf-$(CONFIG_DWARF) += dwarf-regs.o
> libperf-$(CONFIG_DWARF) += skip-callchain-idx.o
> diff --git a/tools/perf/arch/powerpc/util/sym-handling.c
> b/tools/perf/arch/powerpc/util/sym-handling.c
> new file mode 100644
> index 0000000..c9de001
> --- /dev/null
> +++ b/tools/perf/arch/powerpc/util/sym-handling.c
> @@ -0,0 +1,19 @@
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License, version 2, as
> + * published by the Free Software Foundation.
> + *
> + * Copyright (C) 2015 Naveen N. Rao, IBM Corporation
> + */
> +
> +#include "debug.h"
> +#include "symbol.h"
> +
> +#ifdef HAVE_LIBELF_SUPPORT
> +bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
> +{
> + return ehdr.e_type == ET_EXEC ||
> + ehdr.e_type == ET_REL ||
> + ehdr.e_type == ET_DYN;
> +}
> +#endif
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index ac09c60..7f5d237 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -630,6 +630,11 @@ void symsrc__destroy(struct symsrc *ss)
> close(ss->fd);
> }
>
> +bool __weak elf__needs_adjust_symbols(GElf_Ehdr ehdr)
> +{
> + return ehdr.e_type == ET_EXEC || ehdr.e_type == ET_REL;
> +}
> +
> int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
> enum dso_binary_type type)
> {
> @@ -712,8 +717,7 @@ int symsrc__init(struct symsrc *ss, struct dso *dso,
> const char *name,
> ".gnu.prelink_undo",
> NULL) != NULL);
> } else {
> - ss->adjust_symbols = ehdr.e_type == ET_EXEC ||
> - ehdr.e_type == ET_REL;
> + ss->adjust_symbols = elf__needs_adjust_symbols(ehdr);
> }
>
> ss->name = strdup(name);
> diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
> index 0956150..8cb0af4 100644
> --- a/tools/perf/util/symbol.h
> +++ b/tools/perf/util/symbol.h
> @@ -303,4 +303,8 @@ int setup_list(struct strlist **list, const char
> *list_str,
> int setup_intlist(struct intlist **list, const char *list_str,
> const char *list_name);
>
> +#ifdef HAVE_LIBELF_SUPPORT
> +bool elf__needs_adjust_symbols(GElf_Ehdr ehdr);
> +#endif
> +
> #endif /* __PERF_SYMBOL */
> --
> 2.3.5
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
