[PATCHv2 3/8] perf probe powerpc: Fix symbol fixup issues due to ELF type

From: Naveen N. Rao
Date: Mon Dec 15 2014 - 09:51:11 EST


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.rao@xxxxxxxxxxxxxxxxxx>
---
tools/perf/util/symbol-elf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 06fcd1b..7ac4e4c 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -683,7 +683,8 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
NULL) != NULL);
} else {
ss->adjust_symbols = ehdr.e_type == ET_EXEC ||
- ehdr.e_type == ET_REL;
+ ehdr.e_type == ET_REL ||
+ ehdr.e_type == ET_DYN;
}

ss->name = strdup(name);
--
2.1.3

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