[PATCH v2 6/8] perf unwind-libunwind: Move flush/finish access out of local

Ian Rogers
2026-03-05T22:19:52Z

Flush and finish access are relatively simple calls into libunwind,
move them out struct unwind_libunwind_ops. So that the correct version
can be called, add an e_machine variable to maps. This size regression
will go away when the unwind_libunwind_ops no longer need stashing in
the maps. To set the e_machine up pass it into unwind__prepare_access,
which no longer needs to determine the unwind operations based on a
map dso because of this. This also means the maps copying code can
call unwind__prepare_access once for the e_machine rather than once
per map.

Signed-off-by: Ian Rogers <irogers@google.com>
---
.../perf/util/libunwind-arch/libunwind-arch.c | 82 +++++++++++++++++++
.../perf/util/libunwind-arch/libunwind-arch.h | 24 ++++++
.../perf/util/libunwind-arch/libunwind-arm.c | 19 +++++
.../util/libunwind-arch/libunwind-arm64.c | 20 +++++
.../perf/util/libunwind-arch/libunwind-i386.c | 15 ++++
.../util/libunwind-arch/libunwind-loongarch.c | 15 ++++
.../perf/util/libunwind-arch/libunwind-mips.c | 15 ++++
.../util/libunwind-arch/libunwind-ppc32.c | 15 ++++
.../util/libunwind-arch/libunwind-ppc64.c | 15 ++++
.../perf/util/libunwind-arch/libunwind-s390.c | 15 ++++
.../util/libunwind-arch/libunwind-x86_64.c | 15 ++++
tools/perf/util/maps.c | 31 ++++---
tools/perf/util/maps.h | 2 +
tools/perf/util/thread.c | 29 +------
tools/perf/util/unwind-libunwind-local.c | 12 ---
tools/perf/util/unwind-libunwind.c | 61 +++++---------
tools/perf/util/unwind.h | 8 +-
17 files changed, 299 insertions(+), 94 deletions(-)

diff --git a/tools/perf/util/libunwind-arch/libunwind-arch.c b/tools/perf/util/libunwind-arch/libunwind-arch.c
index 5439bf90d161..9692e6c81492 100644
--- a/tools/perf/util/libunwind-arch/libunwind-arch.c
+++ b/tools/perf/util/libunwind-arch/libunwind-arch.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include <elf.h>
#include <errno.h>

@@ -30,3 +31,84 @@ int get_perf_regnum_for_unw_regnum(unsigned int e_machine, int unw_regnum)
return -EINVAL;
}
}
+
+
+void libunwind_arch__flush_access(struct maps *maps)
+{
+ unsigned int e_machine = maps__e_machine(maps);
+
+ switch (e_machine) {
+ case EM_NONE:
+ break; // No libunwind info on the maps.
+ case EM_ARM:
+ __libunwind_arch__flush_access_arm(maps);
+ break;
+ case EM_AARCH64:
+ __libunwind_arch__flush_access_arm64(maps);
+ break;
+ case EM_LOONGARCH:
+ __libunwind_arch__flush_access_loongarch(maps);
+ break;
+ case EM_MIPS:
+ __libunwind_arch__flush_access_mips(maps);
+ break;
+ case EM_PPC:
+ __libunwind_arch__flush_access_ppc32(maps);
+ break;
+ case EM_PPC64:
+ __libunwind_arch__flush_access_ppc64(maps);
+ break;
+ case EM_S390:
+ __libunwind_arch__flush_access_s390(maps);
+ break;
+ case EM_386:
+ __libunwind_arch__flush_access_i386(maps);
+ break;
+ case EM_X86_64:
+ __libunwind_arch__flush_access_x86_64(maps);
+ break;
+ default:
+ pr_err("ELF MACHINE %x is not supported.\n", e_machine);
+ break;
+ }
+}
+
+void libunwind_arch__finish_access(struct maps *maps)
+{
+ unsigned int e_machine = maps__e_machine(maps);
+
+ switch (e_machine) {
+ case EM_NONE:
+ break; // No libunwind info on the maps.
+ case EM_ARM:
+ __libunwind_arch__finish_access_arm(maps);
+ break;
+ case EM_AARCH64:
+ __libunwind_arch__finish_access_arm64(maps);
+ break;
+ case EM_LOONGARCH:
+ __libunwind_arch__finish_access_loongarch(maps);
+ break;
+ case EM_MIPS:
+ __libunwind_arch__finish_access_mips(maps);
+ break;
+ case EM_PPC:
+ __libunwind_arch__finish_access_ppc32(maps);
+ break;
+ case EM_PPC64:
+ __libunwind_arch__finish_access_ppc64(maps);
+ break;
+ case EM_S390:
+ __libunwind_arch__finish_access_s390(maps);
+ break;
+ case EM_386:
+ __libunwind_arch__finish_access_i386(maps);
+ break;
+ case EM_X86_64:
+ __libunwind_arch__finish_access_x86_64(maps);
+ break;
+ default:
+ pr_err("ELF MACHINE %x is not supported.\n", e_machine);
+ break;
+ }
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-arch.h b/tools/perf/util/libunwind-arch/libunwind-arch.h
index e1009c6cb965..c00277a5e914 100644
--- a/tools/perf/util/libunwind-arch/libunwind-arch.h
+++ b/tools/perf/util/libunwind-arch/libunwind-arch.h
@@ -2,6 +2,8 @@
#ifndef __LIBUNWIND_ARCH_H
#define __LIBUNWIND_ARCH_H

+struct maps;
+
int __get_perf_regnum_for_unw_regnum_arm(int unw_regnum);
int __get_perf_regnum_for_unw_regnum_arm64(int unw_regnum);
int __get_perf_regnum_for_unw_regnum_loongarch(int unw_regnum);
@@ -13,4 +15,26 @@ int __get_perf_regnum_for_unw_regnum_i386(int unw_regnum);
int __get_perf_regnum_for_unw_regnum_x86_64(int unw_regnum);
int get_perf_regnum_for_unw_regnum(unsigned int e_machine, int unw_regnum);

+void __libunwind_arch__flush_access_arm(struct maps *maps);
+void __libunwind_arch__flush_access_arm64(struct maps *maps);
+void __libunwind_arch__flush_access_loongarch(struct maps *maps);
+void __libunwind_arch__flush_access_mips(struct maps *maps);
+void __libunwind_arch__flush_access_ppc32(struct maps *maps);
+void __libunwind_arch__flush_access_ppc64(struct maps *maps);
+void __libunwind_arch__flush_access_s390(struct maps *maps);
+void __libunwind_arch__flush_access_i386(struct maps *maps);
+void __libunwind_arch__flush_access_x86_64(struct maps *maps);
+void libunwind_arch__flush_access(struct maps *maps);
+
+void __libunwind_arch__finish_access_arm(struct maps *maps);
+void __libunwind_arch__finish_access_arm64(struct maps *maps);
+void __libunwind_arch__finish_access_loongarch(struct maps *maps);
+void __libunwind_arch__finish_access_mips(struct maps *maps);
+void __libunwind_arch__finish_access_ppc32(struct maps *maps);
+void __libunwind_arch__finish_access_ppc64(struct maps *maps);
+void __libunwind_arch__finish_access_s390(struct maps *maps);
+void __libunwind_arch__finish_access_i386(struct maps *maps);
+void __libunwind_arch__finish_access_x86_64(struct maps *maps);
+void libunwind_arch__finish_access(struct maps *maps);
+
#endif /* __LIBUNWIND_ARCH_H */
diff --git a/tools/perf/util/libunwind-arch/libunwind-arm.c b/tools/perf/util/libunwind-arch/libunwind-arm.c
index 6740ee55b043..bbaf01406c52 100644
--- a/tools/perf/util/libunwind-arch/libunwind-arm.c
+++ b/tools/perf/util/libunwind-arch/libunwind-arm.c
@@ -1,10 +1,15 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/arm/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>

+#ifdef HAVE_LIBUNWIND_ARM_SUPPORT
+#include <libunwind-arm.h>
+#endif
+
int __get_perf_regnum_for_unw_regnum_arm(int unw_regnum)
{
if (unw_regnum < 0 || unw_regnum >= PERF_REG_ARM_MAX) {
@@ -13,3 +18,17 @@ int __get_perf_regnum_for_unw_regnum_arm(int unw_regnum)
}
return unw_regnum;
}
+
+void __libunwind_arch__flush_access_arm(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_ARM_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_arm(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_ARM_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-arm64.c b/tools/perf/util/libunwind-arch/libunwind-arm64.c
index 53b1877dfa04..8ba510089736 100644
--- a/tools/perf/util/libunwind-arch/libunwind-arm64.c
+++ b/tools/perf/util/libunwind-arch/libunwind-arm64.c
@@ -1,9 +1,15 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/arm64/include/uapi/asm/perf_regs.h"
+#include <linux/compiler.h>
#include <errno.h>

+#ifdef HAVE_LIBUNWIND_AARCH64_SUPPORT
+#include <libunwind-aarch64.h>
+#endif
+
int __get_perf_regnum_for_unw_regnum_arm64(int unw_regnum)
{
if (unw_regnum < 0 || unw_regnum >= PERF_REG_ARM64_EXTENDED_MAX) {
@@ -12,3 +18,17 @@ int __get_perf_regnum_for_unw_regnum_arm64(int unw_regnum)
}
return unw_regnum;
}
+
+void __libunwind_arch__flush_access_arm64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_AARCH64_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_arm64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_AARCH64_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-i386.c b/tools/perf/util/libunwind-arch/libunwind-i386.c
index 9eaf4ebff0c2..45ff30c95c1b 100644
--- a/tools/perf/util/libunwind-arch/libunwind-i386.c
+++ b/tools/perf/util/libunwind-arch/libunwind-i386.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/x86/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <linux/kernel.h>
@@ -41,3 +42,17 @@ int __get_perf_regnum_for_unw_regnum_i386(int unw_regnum __maybe_unused)
return perf_i386_regnums[unw_regnum];
#endif // HAVE_LIBUNWIND_X86_SUPPORT
}
+
+void __libunwind_arch__flush_access_i386(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_X86_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_i386(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_X86_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-loongarch.c b/tools/perf/util/libunwind-arch/libunwind-loongarch.c
index 7009410989bc..837aa11e2b9f 100644
--- a/tools/perf/util/libunwind-arch/libunwind-loongarch.c
+++ b/tools/perf/util/libunwind-arch/libunwind-loongarch.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/loongarch/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>
@@ -25,3 +26,17 @@ int __get_perf_regnum_for_unw_regnum_loongarch(int unw_regnum __maybe_unused)
}
#endif // HAVE_LIBUNWIND_LOONGARCH64_SUPPORT
}
+
+void __libunwind_arch__flush_access_loongarch(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_LOONGARCH64_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_loongarch(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_LOONGARCH64_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-mips.c b/tools/perf/util/libunwind-arch/libunwind-mips.c
index 01a506c8079c..1fa81742ff4a 100644
--- a/tools/perf/util/libunwind-arch/libunwind-mips.c
+++ b/tools/perf/util/libunwind-arch/libunwind-mips.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/mips/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>
@@ -27,3 +28,17 @@ int __get_perf_regnum_for_unw_regnum_mips(int unw_regnum __maybe_unused)
}
#endif // HAVE_LIBUNWIND_MIPS_SUPPORT
}
+
+void __libunwind_arch__flush_access_mips(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_MIPS_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_mips(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_MIPS_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-ppc32.c b/tools/perf/util/libunwind-arch/libunwind-ppc32.c
index edcb0ec95dd7..fa8471c74bf3 100644
--- a/tools/perf/util/libunwind-arch/libunwind-ppc32.c
+++ b/tools/perf/util/libunwind-arch/libunwind-ppc32.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/powerpc/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>
@@ -29,3 +30,17 @@ int __get_perf_regnum_for_unw_regnum_ppc32(int unw_regnum __maybe_unused)
}
#endif // HAVE_LIBUNWIND_PPC32_SUPPORT
}
+
+void __libunwind_arch__flush_access_ppc32(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_PPC32_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_ppc32(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_PPC32_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-ppc64.c b/tools/perf/util/libunwind-arch/libunwind-ppc64.c
index 9f57a049600b..2f746e347336 100644
--- a/tools/perf/util/libunwind-arch/libunwind-ppc64.c
+++ b/tools/perf/util/libunwind-arch/libunwind-ppc64.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/powerpc/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>
@@ -31,3 +32,17 @@ int __get_perf_regnum_for_unw_regnum_ppc64(int unw_regnum __maybe_unused)
}
#endif // HAVE_LIBUNWIND_PPC64_SUPPORT
}
+
+void __libunwind_arch__flush_access_ppc64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_PPC64_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_ppc64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_PPC64_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-s390.c b/tools/perf/util/libunwind-arch/libunwind-s390.c
index 9fcc7885ca55..9f68d15438b2 100644
--- a/tools/perf/util/libunwind-arch/libunwind-s390.c
+++ b/tools/perf/util/libunwind-arch/libunwind-s390.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/s390/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <errno.h>
@@ -27,3 +28,17 @@ int __get_perf_regnum_for_unw_regnum_s390(int unw_regnum __maybe_unused)
}
#endif // HAVE_LIBUNWIND_S390X_SUPPORT
}
+
+void __libunwind_arch__flush_access_s390(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_S390X_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_s390(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_S390X_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/libunwind-arch/libunwind-x86_64.c b/tools/perf/util/libunwind-arch/libunwind-x86_64.c
index 6072e3597e61..25e326bd3e15 100644
--- a/tools/perf/util/libunwind-arch/libunwind-x86_64.c
+++ b/tools/perf/util/libunwind-arch/libunwind-x86_64.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
#include "libunwind-arch.h"
#include "../debug.h"
+#include "../maps.h"
#include "../../../arch/x86/include/uapi/asm/perf_regs.h"
#include <linux/compiler.h>
#include <linux/kernel.h>
@@ -50,3 +51,17 @@ int __get_perf_regnum_for_unw_regnum_x86_64(int unw_regnum __maybe_unused)
return perf_x86_64_regnums[unw_regnum];
#endif // HAVE_LIBUNWIND_X86_64_SUPPORT
}
+
+void __libunwind_arch__flush_access_x86_64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_X86_64_SUPPORT
+ unw_flush_cache(maps__addr_space(maps), 0, 0);
+#endif
+}
+
+void __libunwind_arch__finish_access_x86_64(struct maps *maps __maybe_unused)
+{
+#ifdef HAVE_LIBUNWIND_X86_64_SUPPORT
+ unw_destroy_addr_space(maps__addr_space(maps));
+#endif
+}
diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c
index 4092211cff62..8c7b2a1e7642 100644
--- a/tools/perf/util/maps.c
+++ b/tools/perf/util/maps.c
@@ -40,6 +40,7 @@ DECLARE_RC_STRUCT(maps) {
#ifdef HAVE_LIBUNWIND_SUPPORT
void *addr_space;
const struct unwind_libunwind_ops *unwind_libunwind_ops;
+ uint16_t e_machine;
#endif
#ifdef HAVE_LIBDW_SUPPORT
void *libdw_addr_space_dwfl;
@@ -206,6 +207,16 @@ void maps__set_unwind_libunwind_ops(struct maps *maps, const struct unwind_libun
{
RC_CHK_ACCESS(maps)->unwind_libunwind_ops = ops;
}
+
+uint16_t maps__e_machine(const struct maps *maps)
+{
+ return RC_CHK_ACCESS(maps)->e_machine;
+}
+
+void maps__set_e_machine(struct maps *maps, uint16_t e_machine)
+{
+ RC_CHK_ACCESS(maps)->e_machine = e_machine;
+}
#endif
#ifdef HAVE_LIBDW_SUPPORT
void *maps__libdw_addr_space_dwfl(const struct maps *maps)
@@ -1038,6 +1049,9 @@ int maps__copy_from(struct maps *dest, struct maps *parent)
down_write(maps__lock(dest));
down_read(maps__lock(parent));

+#ifdef HAVE_LIBUNWIND_SUPPORT
+ unwind__prepare_access(dest, maps__e_machine(parent));
+#endif
parent_maps_by_address = maps__maps_by_address(parent);
n = maps__nr_maps(parent);
if (maps__nr_maps(dest) == 0) {
@@ -1067,14 +1081,11 @@ int maps__copy_from(struct maps *dest, struct maps *parent)
if (!new)
err = -ENOMEM;
else {
- err = unwind__prepare_access(dest, new, NULL);
- if (!err) {
- dest_maps_by_address[i] = new;
- map__set_kmap_maps(new, dest);
- if (dest_maps_by_name)
- dest_maps_by_name[i] = map__get(new);
- RC_CHK_ACCESS(dest)->nr_maps = i + 1;
- }
+ dest_maps_by_address[i] = new;
+ map__set_kmap_maps(new, dest);
+ if (dest_maps_by_name)
+ dest_maps_by_name[i] = map__get(new);
+ RC_CHK_ACCESS(dest)->nr_maps = i + 1;
}
if (err)
map__put(new);
@@ -1099,9 +1110,7 @@ int maps__copy_from(struct maps *dest, struct maps *parent)
if (!new)
err = -ENOMEM;
else {
- err = unwind__prepare_access(dest, new, NULL);
- if (!err)
- err = __maps__insert(dest, new);
+ err = __maps__insert(dest, new);
}
map__put(new);
}
diff --git a/tools/perf/util/maps.h b/tools/perf/util/maps.h
index 20c52084ba9e..6469f62c41a8 100644
--- a/tools/perf/util/maps.h
+++ b/tools/perf/util/maps.h
@@ -51,6 +51,8 @@ void *maps__addr_space(const struct maps *maps);
void maps__set_addr_space(struct maps *maps, void *addr_space);
const struct unwind_libunwind_ops *maps__unwind_libunwind_ops(const struct maps *maps);
void maps__set_unwind_libunwind_ops(struct maps *maps, const struct unwind_libunwind_ops *ops);
+uint16_t maps__e_machine(const struct maps *maps);
+void maps__set_e_machine(struct maps *maps, uint16_t e_machine);
#endif
#ifdef HAVE_LIBDW_SUPPORT
void *maps__libdw_addr_space_dwfl(const struct maps *maps);
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 22be77225bb0..c5df11ad329c 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -358,41 +358,20 @@ size_t thread__fprintf(struct thread *thread, FILE *fp)
int thread__insert_map(struct thread *thread, struct map *map)
{
int ret;
+ uint16_t e_machine = thread__e_machine(thread, /*machine=*/NULL, /*e_flags=*/NULL);

- ret = unwind__prepare_access(thread__maps(thread), map, NULL);
+ ret = unwind__prepare_access(thread__maps(thread), e_machine);
if (ret)
return ret;

return maps__fixup_overlap_and_insert(thread__maps(thread), map);
}

-struct thread__prepare_access_maps_cb_args {
- int err;
- struct maps *maps;
-};
-
-static int thread__prepare_access_maps_cb(struct map *map, void *data)
-{
- bool initialized = false;
- struct thread__prepare_access_maps_cb_args *args = data;
-
- args->err = unwind__prepare_access(args->maps, map, &initialized);
-
- return (args->err || initialized) ? 1 : 0;
-}
-
static int thread__prepare_access(struct thread *thread)
{
- struct thread__prepare_access_maps_cb_args args = {
- .err = 0,
- };
-
- if (dwarf_callchain_users) {
- args.maps = thread__maps(thread);
- maps__for_each_map(thread__maps(thread), thread__prepare_access_maps_cb, &args);
- }
+ uint16_t e_machine = thread__e_machine(thread, /*machine=*/NULL, /*e_flags=*/NULL);

- return args.err;
+ return unwind__prepare_access(thread__maps(thread), e_machine);
}

static int thread__clone_maps(struct thread *thread, struct thread *parent, bool do_maps_clone)
diff --git a/tools/perf/util/unwind-libunwind-local.c b/tools/perf/util/unwind-libunwind-local.c
index 3ecdb468b859..8f0128ba05a7 100644
--- a/tools/perf/util/unwind-libunwind-local.c
+++ b/tools/perf/util/unwind-libunwind-local.c
@@ -722,16 +722,6 @@ static int _unwind__prepare_access(struct maps *maps)
return 0;
}

-static void _unwind__flush_access(struct maps *maps)
-{
- unw_flush_cache(maps__addr_space(maps), 0, 0);
-}
-
-static void _unwind__finish_access(struct maps *maps)
-{
- unw_destroy_addr_space(maps__addr_space(maps));
-}
-
static int get_entries(struct unwind_info *ui, unwind_entry_cb_t cb,
void *arg, int max_stack)
{
@@ -821,8 +811,6 @@ static int _unwind__get_entries(unwind_entry_cb_t cb, void *arg,
static struct unwind_libunwind_ops
_unwind_libunwind_ops = {
.prepare_access = _unwind__prepare_access,
- .flush_access = _unwind__flush_access,
- .finish_access = _unwind__finish_access,
.get_entries = _unwind__get_entries,
};

diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index a0016b897dae..eaee7b78d87c 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -7,76 +7,55 @@
#include "debug.h"
#include "env.h"
#include "callchain.h"
+#include "libunwind-arch/libunwind-arch.h"
+#include <dwarf-regs.h>
+#include <elf.h>

struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;
struct unwind_libunwind_ops __weak *arm64_unwind_libunwind_ops;

-int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized)
+int unwind__prepare_access(struct maps *maps, uint16_t e_machine)
{
- const char *arch;
- enum dso_type dso_type;
struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
- struct dso *dso = map__dso(map);
- struct machine *machine;
- int err;

if (!dwarf_callchain_users)
return 0;

if (maps__addr_space(maps)) {
- pr_debug("unwind: thread map already set, dso=%s\n", dso__name(dso));
- if (initialized)
- *initialized = true;
+ pr_debug3("unwind: thread map already set\n");
return 0;
}

- machine = maps__machine(maps);
- /* env->arch is NULL for live-mode (i.e. perf top) */
- if (!machine->env || !machine->env->arch)
- goto out_register;
-
- dso_type = dso__type(dso, machine);
- if (dso_type == DSO__TYPE_UNKNOWN)
- return 0;
-
- arch = perf_env__arch(machine->env);
-
- if (!strcmp(arch, "x86")) {
- if (dso_type != DSO__TYPE_64BIT)
+ if (e_machine != EM_HOST) {
+ /* If not live/local mode. */
+ switch (e_machine) {
+ case EM_386:
ops = x86_32_unwind_libunwind_ops;
- } else if (!strcmp(arch, "arm64") || !strcmp(arch, "arm")) {
- if (dso_type == DSO__TYPE_64BIT)
+ break;
+ case EM_AARCH64:
ops = arm64_unwind_libunwind_ops;
- }
-
- if (!ops) {
- pr_warning_once("unwind: target platform=%s is not supported\n", arch);
+ break;
+ default:
+ pr_warning_once("unwind: ELF machine type %d is not supported\n",
+ e_machine);
return 0;
+ }
}
-out_register:
maps__set_unwind_libunwind_ops(maps, ops);
+ maps__set_e_machine(maps, e_machine);

- err = maps__unwind_libunwind_ops(maps)->prepare_access(maps);
- if (initialized)
- *initialized = err ? false : true;
- return err;
+ return maps__unwind_libunwind_ops(maps)->prepare_access(maps);
}

void unwind__flush_access(struct maps *maps)
{
- const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
-
- if (ops)
- ops->flush_access(maps);
+ libunwind_arch__flush_access(maps);
}

void unwind__finish_access(struct maps *maps)
{
- const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
-
- if (ops)
- ops->finish_access(maps);
+ libunwind_arch__finish_access(maps);
}

int libunwind__get_entries(unwind_entry_cb_t cb, void *arg,
diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h
index e32d39ab41c6..09fc60df262d 100644
--- a/tools/perf/util/unwind.h
+++ b/tools/perf/util/unwind.h
@@ -2,6 +2,7 @@
#ifndef __UNWIND_H
#define __UNWIND_H

+#include <stdint.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include "util/map_symbol.h"
@@ -20,8 +21,6 @@ typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg);

struct unwind_libunwind_ops {
int (*prepare_access)(struct maps *maps);
- void (*flush_access)(struct maps *maps);
- void (*finish_access)(struct maps *maps);
int (*get_entries)(unwind_entry_cb_t cb, void *arg,
struct thread *thread,
struct perf_sample *data, int max_stack, bool best_effort);
@@ -53,13 +52,12 @@ int libunwind__get_entries(unwind_entry_cb_t cb, void *arg,
struct thread *thread,
struct perf_sample *data, int max_stack,
bool best_effort);
-int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized);
+int unwind__prepare_access(struct maps *maps, uint16_t e_machine);
void unwind__flush_access(struct maps *maps);
void unwind__finish_access(struct maps *maps);
#else
static inline int unwind__prepare_access(struct maps *maps __maybe_unused,
- struct map *map __maybe_unused,
- bool *initialized __maybe_unused)
+ uint16_t e_machine __maybe_unused)
{
return 0;
}
--
2.53.0.473.g4a7958ca14-goog