Allow perf probe to work on ppc ABIv1 without the need to specify the
leading dot '.' for functions. 'perf probe do_fork' works with this
patch.
We do this by changing how symbol name comparison works on ppc ABIv1 -
we simply ignore and skip over the initial dot, if one exists, during
symbol name comparison.
Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com>
---
Changes:
This patch has been redone since upstream changed quite a bit. We now implement
arch-specific helper during symbol name comparison to ignore leading dot on ppc
symbols.
tools/perf/arch/powerpc/util/sym-handling.c | 13 +++++++++++++
tools/perf/util/map.c | 5 +++++
tools/perf/util/map.h | 3 ++-
tools/perf/util/symbol.c | 4 ++--
4 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/tools/perf/arch/powerpc/util/sym-handling.c
b/tools/perf/arch/powerpc/util/sym-handling.c
index 5522a40..2de2cc4 100644
--- a/tools/perf/arch/powerpc/util/sym-handling.c
+++ b/tools/perf/arch/powerpc/util/sym-handling.c
@@ -8,6 +8,7 @@
#include "debug.h"
#include "symbol.h"
+#include "map.h"
#ifdef HAVE_LIBELF_SUPPORT
bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
@@ -36,4 +37,16 @@ int arch__choose_best_symbol(struct symbol *syma,
return SYMBOL_A;
}
+
+/* Allow matching against dot variants */
+int arch__compare_symbol_names(const char *namea, const char *nameb)
+{
+ /* Skip over initial dot */
+ if (*namea == '.')
+ namea++;
+ if (*nameb == '.')
+ nameb++;
+
+ return strcmp(namea, nameb);
+}
#endif
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index a14f08f..cd0e335 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -292,6 +292,11 @@ int map__load(struct map *map, symbol_filter_t filter)
return 0;
}
+int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
+{
+ return strcmp(namea, nameb);
+}
+
struct symbol *map__find_symbol(struct map *map, u64 addr,
symbol_filter_t filter)
{
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index ec19c59..4e0c729 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -124,7 +124,7 @@ struct thread;
*/
#define __map__for_each_symbol_by_name(map, sym_name, pos, filter) \
for (pos = map__find_symbol_by_name(map, sym_name, filter); \
- pos && strcmp(pos->name, sym_name) == 0; \
+ pos && arch__compare_symbol_names(pos->name, sym_name) == 0;
\
pos = symbol__next_by_name(pos))
#define map__for_each_symbol_by_name(map, sym_name, pos) \
@@ -132,6 +132,7 @@ struct thread;
typedef int (*symbol_filter_t)(struct map *map, struct symbol *sym);
+int arch__compare_symbol_names(const char *namea, const char *nameb);
void map__init(struct map *map, enum map_type type,
u64 start, u64 end, u64 pgoff, struct dso *dso);
struct map *map__new(struct machine *machine, u64 start, u64 len,
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index f805757..45ba48a 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -411,7 +411,7 @@ static struct symbol *symbols__find_by_name(struct rb_root
*symbols,
int cmp;
s = rb_entry(n, struct symbol_name_rb_node, rb_node);
- cmp = strcmp(name, s->sym.name);
+ cmp = arch__compare_symbol_names(name, s->sym.name);
if (cmp < 0)
n = n->rb_left;
@@ -429,7 +429,7 @@ static struct symbol *symbols__find_by_name(struct rb_root
*symbols,
struct symbol_name_rb_node *tmp;
tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
- if (strcmp(tmp->sym.name, s->sym.name))
+ if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
break;
s = tmp;
--
2.3.5
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