[PATCH] ARM: ftrace: fix syscall name matching

From: Rabin Vincent
Date: Mon Nov 14 2016 - 08:04:11 EST


From: Rabin Vincent <rabinv@xxxxxxxx>

ARM has a few system calls (most notably mmap) for which the names of
the functions which are referenced in the syscall table do not match the
names of the syscall tracepoints. As a consequence of this, these
tracepoints are not made available. Implement
arch_syscall_match_sym_name to fix this and allow tracing even these
system calls.

Signed-off-by: Rabin Vincent <rabinv@xxxxxxxx>
---
arch/arm/include/asm/ftrace.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/arch/arm/include/asm/ftrace.h b/arch/arm/include/asm/ftrace.h
index bfe2a2f..8467909 100644
--- a/arch/arm/include/asm/ftrace.h
+++ b/arch/arm/include/asm/ftrace.h
@@ -54,6 +54,27 @@ static inline void *return_address(unsigned int level)

#define ftrace_return_address(n) return_address(n)

+#define ARCH_HAS_SYSCALL_MATCH_SYM_NAME
+
+static inline bool arch_syscall_match_sym_name(const char *sym,
+ const char *name)
+{
+ /* Skip sys_ */
+ sym += 4;
+ name += 4;
+
+ if (!strcmp(sym, "mmap2"))
+ sym = "mmap_pgoff";
+ else if (!strcmp(sym, "statfs64_wrapper"))
+ sym = "statfs64";
+ else if (!strcmp(sym, "fstatfs64_wrapper"))
+ sym = "fstatfs64";
+ else if (!strcmp(sym, "arm_fadvise64_64"))
+ sym = "fadvise64_64";
+
+ return !strcmp(sym, name);
+}
+
#endif /* ifndef __ASSEMBLY__ */

#endif /* _ASM_ARM_FTRACE */
--
2.1.4