[PATCH v3 3/7] perf probe/ppc: Use the right prefix when ignoring SyS symbols on ppc

From: Naveen N. Rao
Date: Tue Apr 28 2015 - 08:06:27 EST


Use the proper prefix when ignoring SyS symbols on ppc ABIv1. While at
it, generalize symbol selection so architectures can implement their
own logic.

Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
---
Changes:
- Move logic to arch helper.

tools/perf/arch/powerpc/util/sym-handling.c | 20 ++++++++++++++++++++
tools/perf/util/symbol.c | 21 ++++++++++++---------
tools/perf/util/symbol.h | 5 +++++
3 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c
index c9de001..5522a40 100644
--- a/tools/perf/arch/powerpc/util/sym-handling.c
+++ b/tools/perf/arch/powerpc/util/sym-handling.c
@@ -17,3 +17,23 @@ bool elf__needs_adjust_symbols(GElf_Ehdr ehdr)
ehdr.e_type == ET_DYN;
}
#endif
+
+#if !defined(_CALL_ELF) || _CALL_ELF != 2
+int arch__choose_best_symbol(struct symbol *syma,
+ struct symbol *symb __maybe_unused)
+{
+ char *sym = syma->name;
+
+ /* Skip over any initial dot */
+ if (*sym == '.')
+ sym++;
+
+ /* Avoid "SyS" kernel syscall aliases */
+ if (strlen(sym) >= 3 && !strncmp(sym, "SyS", 3))
+ return SYMBOL_B;
+ if (strlen(sym) >= 10 && !strncmp(sym, "compat_SyS", 10))
+ return SYMBOL_B;
+
+ return SYMBOL_A;
+}
+#endif
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 201f6c4c..f805757 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -85,8 +85,17 @@ static int prefix_underscores_count(const char *str)
return tail - str;
}

-#define SYMBOL_A 0
-#define SYMBOL_B 1
+int __weak arch__choose_best_symbol(struct symbol *syma,
+ struct symbol *symb __maybe_unused)
+{
+ /* Avoid "SyS" kernel syscall aliases */
+ if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
+ return SYMBOL_B;
+ if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
+ return SYMBOL_B;
+
+ return SYMBOL_A;
+}

static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
{
@@ -134,13 +143,7 @@ static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
else if (na < nb)
return SYMBOL_B;

- /* Avoid "SyS" kernel syscall aliases */
- if (na >= 3 && !strncmp(syma->name, "SyS", 3))
- return SYMBOL_B;
- if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
- return SYMBOL_B;
-
- return SYMBOL_A;
+ return arch__choose_best_symbol(syma, symb);
}

void symbols__fixup_duplicate(struct rb_root *symbols)
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 8cb0af4..bd50ba0 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -307,4 +307,9 @@ int setup_intlist(struct intlist **list, const char *list_str,
bool elf__needs_adjust_symbols(GElf_Ehdr ehdr);
#endif

+#define SYMBOL_A 0
+#define SYMBOL_B 1
+
+int arch__choose_best_symbol(struct symbol *syma, struct symbol *symb);
+
#endif /* __PERF_SYMBOL */
--
2.3.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/