[PATCH v9 13/14] perf callchain: Support x86 target platform

From: He Kuang
Date: Thu Jun 02 2016 - 23:34:32 EST


Support x86(32-bit) cross platform callchain unwind.

Signed-off-by: He Kuang <hekuang@xxxxxxxxxx>
---
tools/perf/arch/x86/util/unwind-libunwind.c | 6 +++--
tools/perf/config/Makefile | 8 +++++++
tools/perf/util/Build | 1 +
tools/perf/util/libunwind/x86_32.c | 37 +++++++++++++++++++++++++++++
tools/perf/util/unwind-libunwind.c | 15 ++++++++++--
5 files changed, 63 insertions(+), 4 deletions(-)
create mode 100644 tools/perf/util/libunwind/x86_32.c

diff --git a/tools/perf/arch/x86/util/unwind-libunwind.c b/tools/perf/arch/x86/util/unwind-libunwind.c
index db25e93..4f16661 100644
--- a/tools/perf/arch/x86/util/unwind-libunwind.c
+++ b/tools/perf/arch/x86/util/unwind-libunwind.c
@@ -1,12 +1,14 @@

+#ifndef REMOTE_UNWIND_LIBUNWIND
#include <errno.h>
#include <libunwind.h>
#include "perf_regs.h"
#include "../../util/unwind.h"
#include "../../util/debug.h"
+#endif

#ifdef HAVE_ARCH_X86_64_SUPPORT
-int libunwind__arch_reg_id(int regnum)
+int LIBUNWIND__ARCH_REG_ID(int regnum)
{
int id;

@@ -70,7 +72,7 @@ int libunwind__arch_reg_id(int regnum)
return id;
}
#else
-int libunwind__arch_reg_id(int regnum)
+int LIBUNWIND__ARCH_REG_ID(int regnum)
{
int id;

diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index 3918687..34999fb 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -354,6 +354,14 @@ endif

ifndef NO_LIBUNWIND
have_libunwind :=
+
+ ifeq ($(feature-libunwind-x86), 1)
+ $(call detected,CONFIG_LIBUNWIND_X86)
+ CFLAGS += -DHAVE_LIBUNWIND_X86_SUPPORT
+ LDFLAGS += -lunwind-x86
+ have_libunwind = 1
+ endif
+
ifneq ($(feature-libunwind), 1)
msg := $(warning No libunwind found. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR);
NO_LOCAL_LIBUNWIND := 1
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index 004fb1d..7746e09 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -101,6 +101,7 @@ libperf-$(CONFIG_DWARF) += dwarf-aux.o
libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind-local.o
libperf-$(CONFIG_LIBUNWIND) += unwind-libunwind.o
+libperf-$(CONFIG_LIBUNWIND_X86) += libunwind/x86_32.o

libperf-$(CONFIG_LIBBABELTRACE) += data-convert-bt.o

diff --git a/tools/perf/util/libunwind/x86_32.c b/tools/perf/util/libunwind/x86_32.c
new file mode 100644
index 0000000..d98c17e
--- /dev/null
+++ b/tools/perf/util/libunwind/x86_32.c
@@ -0,0 +1,37 @@
+/*
+ * This file setups defines to compile arch specific binary from the
+ * generic one.
+ *
+ * The function 'LIBUNWIND__ARCH_REG_ID' name is set according to arch
+ * name and the defination of this function is included directly from
+ * 'arch/x86/util/unwind-libunwind.c', to make sure that this function
+ * is defined no matter what arch the host is.
+ *
+ * Finally, the arch specific unwind methods are exported which will
+ * be assigned to each x86 thread.
+ */
+
+#define REMOTE_UNWIND_LIBUNWIND
+#define LIBUNWIND__ARCH_REG_ID(regnum) libunwind__x86_reg_id(regnum)
+
+#include "unwind.h"
+#include "debug.h"
+#include "libunwind-x86.h"
+#include <../../../../arch/x86/include/uapi/asm/perf_regs.h>
+
+/* HAVE_ARCH_X86_64_SUPPORT is used in'arch/x86/util/unwind-libunwind.c'
+ * for x86_32, we undef it to compile code for x86_32 only.
+ */
+#undef HAVE_ARCH_X86_64_SUPPORT
+#include "../../arch/x86/util/unwind-libunwind.c"
+
+/* Explicitly define NO_LIBUNWIND_DEBUG_FRAME, because non-ARM has no
+ * dwarf_find_debug_frame() function.
+ */
+#ifndef NO_LIBUNWIND_DEBUG_FRAME
+#define NO_LIBUNWIND_DEBUG_FRAME
+#endif
+#include "util/unwind-libunwind-local.c"
+
+struct unwind_libunwind_ops *
+x86_32_unwind_libunwind_ops = &_unwind_libunwind_ops;
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index 1d72819..c4d6388 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -5,6 +5,7 @@
#include "arch/common.h"

struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
+struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;

static void unwind__register_ops(struct thread *thread,
struct unwind_libunwind_ops *ops)
@@ -16,6 +17,7 @@ int unwind__prepare_access(struct thread *thread, struct map *map)
{
const char *arch;
enum dso_type dso_type;
+ struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;

if (thread->addr_space) {
pr_debug("unwind: thread map already set, dso=%s\n",
@@ -31,9 +33,18 @@ int unwind__prepare_access(struct thread *thread, struct map *map)
return 0;

arch = normalize_arch(thread->mg->machine->env->arch);
- pr_debug("unwind: target platform=%s\n", arch);

- unwind__register_ops(thread, local_unwind_libunwind_ops);
+ if (!strcmp(arch, "x86")) {
+ if (dso_type != DSO__TYPE_64BIT)
+ ops = x86_32_unwind_libunwind_ops;
+ }
+
+ if (!ops) {
+ pr_err("unwind: target platform=%s is not supported\n", arch);
+ return -1;
+ }
+
+ unwind__register_ops(thread, ops);

return thread->unwind_libunwind_ops->prepare_access(thread);
}
--
1.8.5.2