Re: [PATCH v1 04/23] perf unwind-libdw: fix a cross-arch unwinding bug

Arnaldo Carvalho de Melo
2026-01-20T16:02:28Z

On Fri, Jan 16, 2026 at 09:28:30PM -0800, Ian Rogers wrote:
> From: Shimin Guo <shimin.guo@skydio.com>
>
> The set_initial_registers field of Dwfl_Thread_Callbacks needs to be set
> according to the arch of the stack samples being analyzed, not the arch
> that perf itself is built for. Currently perf fails to unwind stack samples
> collected from archs different from that of the host perf is running on.
> This patch moves the arch-specific implementations of set_initial_registers
> from tools/perf/arch to tools/perf/utli/unwind-libdw-arch, similar to the
> way the perf-regs-arch folder contains arch-specific functions related to
> registers, and chooses the implementation based on the arch of the data
> being processed.

Since this one is coming thru you, we need your:

Signed-off-by: Ian Rogers <irogers@google.com>

Ok?

I'm adding it here, please ack.

- Arnaldo

> Signed-off-by: Shimin Guo <shimin.guo@skydio.com>
> Reviewed-by: Ian Rogers <irogers@google.com>
> Acked-by: Namhyung Kim <namhyung@kernel.org>
> ---
> tools/perf/arch/arm/util/Build | 1 -
> tools/perf/arch/arm64/util/Build | 1 -
> tools/perf/arch/csky/util/Build | 2 -
> tools/perf/arch/powerpc/util/Build | 1 -
> tools/perf/arch/riscv/util/Build | 1 -
> tools/perf/arch/s390/util/Build | 2 -
> tools/perf/arch/x86/util/Build | 1 -
> tools/perf/util/Build | 1 +
> tools/perf/util/unwind-libdw-arch/Build | 8 +++
> .../unwind-libdw-arch/unwind-libdw-arm.c} | 10 ++--
> .../unwind-libdw-arch/unwind-libdw-arm64.c} | 10 ++--
> .../unwind-libdw-arch/unwind-libdw-csky.c} | 10 ++--
> .../unwind-libdw-loongarch.c} | 10 ++--
> .../unwind-libdw-arch/unwind-libdw-powerpc.c} | 10 ++--
> .../unwind-libdw-arch/unwind-libdw-riscv.c} | 10 ++--
> .../unwind-libdw-arch/unwind-libdw-s390.c} | 14 ++---
> .../unwind-libdw-arch/unwind-libdw-x86.c} | 8 +--
> tools/perf/util/unwind-libdw.c | 51 ++++++++++++++++---
> tools/perf/util/unwind-libdw.h | 10 +++-
> 19 files changed, 104 insertions(+), 57 deletions(-)
> create mode 100644 tools/perf/util/unwind-libdw-arch/Build
> rename tools/perf/{arch/arm/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-arm.c} (80%)
> rename tools/perf/{arch/arm64/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-arm64.c} (87%)
> rename tools/perf/{arch/csky/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-csky.c} (90%)
> rename tools/perf/{arch/loongarch/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-loongarch.c} (86%)
> rename tools/perf/{arch/powerpc/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-powerpc.c} (89%)
> rename tools/perf/{arch/riscv/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-riscv.c} (87%)
> rename tools/perf/{arch/s390/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-s390.c} (84%)
> rename tools/perf/{arch/x86/util/unwind-libdw.c => util/unwind-libdw-arch/unwind-libdw-x86.c} (87%)
>
> diff --git a/tools/perf/arch/arm/util/Build b/tools/perf/arch/arm/util/Build
> index fd695e1fdaee..3291f893b943 100644
> --- a/tools/perf/arch/arm/util/Build
> +++ b/tools/perf/arch/arm/util/Build
> @@ -1,6 +1,5 @@
> perf-util-y += perf_regs.o
>
> perf-util-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
>
> perf-util-y += pmu.o auxtrace.o cs-etm.o
> diff --git a/tools/perf/arch/arm64/util/Build b/tools/perf/arch/arm64/util/Build
> index d63881081d2e..0177af19cc00 100644
> --- a/tools/perf/arch/arm64/util/Build
> +++ b/tools/perf/arch/arm64/util/Build
> @@ -1,4 +1,3 @@
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> perf-util-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
> perf-util-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
> perf-util-y += ../../arm/util/auxtrace.o
> diff --git a/tools/perf/arch/csky/util/Build b/tools/perf/arch/csky/util/Build
> index 5e6ea82c4202..6b2d0e021b11 100644
> --- a/tools/perf/arch/csky/util/Build
> +++ b/tools/perf/arch/csky/util/Build
> @@ -1,3 +1 @@
> perf-util-y += perf_regs.o
> -
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> diff --git a/tools/perf/arch/powerpc/util/Build b/tools/perf/arch/powerpc/util/Build
> index 3d0d5427aef7..5fd28ec713a4 100644
> --- a/tools/perf/arch/powerpc/util/Build
> +++ b/tools/perf/arch/powerpc/util/Build
> @@ -9,5 +9,4 @@ perf-util-y += evsel.o
> perf-util-$(CONFIG_LIBDW) += skip-callchain-idx.o
>
> perf-util-$(CONFIG_LIBUNWIND) += unwind-libunwind.o
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> perf-util-y += auxtrace.o
> diff --git a/tools/perf/arch/riscv/util/Build b/tools/perf/arch/riscv/util/Build
> index 58a672246024..628b9ebd418b 100644
> --- a/tools/perf/arch/riscv/util/Build
> +++ b/tools/perf/arch/riscv/util/Build
> @@ -2,4 +2,3 @@ perf-util-y += perf_regs.o
> perf-util-y += header.o
>
> perf-util-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> diff --git a/tools/perf/arch/s390/util/Build b/tools/perf/arch/s390/util/Build
> index c64eb18dbdae..5391d26fedd4 100644
> --- a/tools/perf/arch/s390/util/Build
> +++ b/tools/perf/arch/s390/util/Build
> @@ -2,8 +2,6 @@ perf-util-y += header.o
> perf-util-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o
> perf-util-y += perf_regs.o
>
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> -
> perf-util-y += machine.o
> perf-util-y += pmu.o
>
> diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build
> index c0dc5965f362..fad256252bb9 100644
> --- a/tools/perf/arch/x86/util/Build
> +++ b/tools/perf/arch/x86/util/Build
> @@ -12,7 +12,6 @@ perf-util-y += evsel.o
> perf-util-y += iostat.o
>
> perf-util-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
> -perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
>
> perf-util-y += auxtrace.o
> perf-util-y += archinsn.o
> diff --git a/tools/perf/util/Build b/tools/perf/util/Build
> index 4915f237ba9e..5efec73be474 100644
> --- a/tools/perf/util/Build
> +++ b/tools/perf/util/Build
> @@ -227,6 +227,7 @@ perf-util-$(CONFIG_LIBDW) += annotate-data.o
> perf-util-$(CONFIG_LIBDW) += libdw.o
>
> perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
> +perf-util-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw-arch/
> perf-util-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind-local.o
> perf-util-$(CONFIG_LIBUNWIND) += unwind-libunwind.o
> perf-util-$(CONFIG_LIBUNWIND_X86) += libunwind/x86_32.o
> diff --git a/tools/perf/util/unwind-libdw-arch/Build b/tools/perf/util/unwind-libdw-arch/Build
> new file mode 100644
> index 000000000000..ef17a83a7813
> --- /dev/null
> +++ b/tools/perf/util/unwind-libdw-arch/Build
> @@ -0,0 +1,8 @@
> +perf-util-y += unwind-libdw-x86.o
> +perf-util-y += unwind-libdw-arm.o
> +perf-util-y += unwind-libdw-arm64.o
> +perf-util-y += unwind-libdw-csky.o
> +perf-util-y += unwind-libdw-loongarch.o
> +perf-util-y += unwind-libdw-powerpc.o
> +perf-util-y += unwind-libdw-riscv.o
> +perf-util-y += unwind-libdw-s390.o
> diff --git a/tools/perf/arch/arm/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-arm.c
> similarity index 80%
> rename from tools/perf/arch/arm/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-arm.c
> index fbb643f224ec..56e9b5975bcc 100644
> --- a/tools/perf/arch/arm/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-arm.c
> @@ -1,11 +1,11 @@
> // SPDX-License-Identifier: GPL-2.0
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../../util/unwind-libdw.h"
> -#include "../../../util/perf_regs.h"
> -#include "../../../util/sample.h"
> +#include "../arch/arm/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_arm(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/arm64/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-arm64.c
> similarity index 87%
> rename from tools/perf/arch/arm64/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-arm64.c
> index b89b0a7e5ad9..29b6833e036c 100644
> --- a/tools/perf/arch/arm64/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-arm64.c
> @@ -1,11 +1,11 @@
> // SPDX-License-Identifier: GPL-2.0
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../../util/unwind-libdw.h"
> -#include "../../../util/perf_regs.h"
> -#include "../../../util/sample.h"
> +#include "../arch/arm64/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_arm64(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/csky/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-csky.c
> similarity index 90%
> rename from tools/perf/arch/csky/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-csky.c
> index b20b1569783d..2556d034c32a 100644
> --- a/tools/perf/arch/csky/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-csky.c
> @@ -2,12 +2,12 @@
> // Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd.
>
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../util/unwind-libdw.h"
> -#include "../../util/perf_regs.h"
> -#include "../../util/event.h"
> +#include "../arch/csky/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_csky(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/loongarch/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-loongarch.c
> similarity index 86%
> rename from tools/perf/arch/loongarch/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-loongarch.c
> index 60b1144bedd5..5fca673508be 100644
> --- a/tools/perf/arch/loongarch/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-loongarch.c
> @@ -2,12 +2,12 @@
> /* Copyright (C) 2020-2023 Loongson Technology Corporation Limited */
>
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../util/unwind-libdw.h"
> -#include "../../util/perf_regs.h"
> -#include "../../util/sample.h"
> +#include "../arch/loongarch/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_loongarch(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/powerpc/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-powerpc.c
> similarity index 89%
> rename from tools/perf/arch/powerpc/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-powerpc.c
> index 82d0c28ae345..1560db45e7b4 100644
> --- a/tools/perf/arch/powerpc/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-powerpc.c
> @@ -1,10 +1,10 @@
> // SPDX-License-Identifier: GPL-2.0
> #include <elfutils/libdwfl.h>
> #include <linux/kernel.h>
> -#include "perf_regs.h"
> -#include "../../../util/unwind-libdw.h"
> -#include "../../../util/perf_regs.h"
> -#include "../../../util/sample.h"
> +#include "../arch/powerpc/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> /* See backends/ppc_initreg.c and backends/ppc_regs.c in elfutils. */
> static const int special_regs[3][2] = {
> @@ -13,7 +13,7 @@ static const int special_regs[3][2] = {
> { 109, PERF_REG_POWERPC_CTR },
> };
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_powerpc(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/riscv/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-riscv.c
> similarity index 87%
> rename from tools/perf/arch/riscv/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-riscv.c
> index dc1476e16321..c2e2c4b6b2e0 100644
> --- a/tools/perf/arch/riscv/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-riscv.c
> @@ -2,12 +2,12 @@
> /* Copyright (C) 2019 Hangzhou C-SKY Microsystems co.,ltd. */
>
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../util/unwind-libdw.h"
> -#include "../../util/perf_regs.h"
> -#include "../../util/sample.h"
> +#include "../arch/riscv/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_riscv(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/s390/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-s390.c
> similarity index 84%
> rename from tools/perf/arch/s390/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-s390.c
> index c27c7a0d1076..1e05e9d9d95f 100644
> --- a/tools/perf/arch/s390/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-s390.c
> @@ -1,14 +1,14 @@
> #include <linux/kernel.h>
> #include <elfutils/libdwfl.h>
> -#include "../../util/unwind-libdw.h"
> -#include "../../util/perf_regs.h"
> -#include "../../util/event.h"
> -#include "../../util/sample.h"
> -#include "dwarf-regs-table.h"
> -#include "perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> +#include "util/event.h"
> +#include "util/sample.h"
> +#include "../arch/s390/include/dwarf-regs-table.h"
> +#include "../arch/s390/include/uapi/asm/perf_regs.h"
>
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_s390(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/arch/x86/util/unwind-libdw.c b/tools/perf/util/unwind-libdw-arch/unwind-libdw-x86.c
> similarity index 87%
> rename from tools/perf/arch/x86/util/unwind-libdw.c
> rename to tools/perf/util/unwind-libdw-arch/unwind-libdw-x86.c
> index 798493e887d7..dd27545a4a68 100644
> --- a/tools/perf/arch/x86/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw-arch/unwind-libdw-x86.c
> @@ -1,11 +1,11 @@
> // SPDX-License-Identifier: GPL-2.0
> #include <elfutils/libdwfl.h>
> -#include "perf_regs.h"
> -#include "../../../util/unwind-libdw.h"
> -#include "../../../util/perf_regs.h"
> +#include "../arch/x86/include/uapi/asm/perf_regs.h"
> +#include "util/unwind-libdw.h"
> +#include "util/perf_regs.h"
> #include "util/sample.h"
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg)
> +bool libdw_set_initial_registers_x86(Dwfl_Thread *thread, void *arg)
> {
> struct unwind_info *ui = arg;
> struct regs_dump *user_regs = perf_sample__user_regs(ui->sample);
> diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c
> index 3ff427a49e4c..b2e194a8be39 100644
> --- a/tools/perf/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw.c
> @@ -225,11 +225,45 @@ static bool memory_read(Dwfl *dwfl __maybe_unused, Dwarf_Addr addr, Dwarf_Word *
> return true;
> }
>
> -static const Dwfl_Thread_Callbacks callbacks = {
> - .next_thread = next_thread,
> - .memory_read = memory_read,
> - .set_initial_registers = libdw__arch_set_initial_registers,
> -};
> +#define DEFINE_DWFL_THREAD_CALLBACKS(arch) \
> +static const Dwfl_Thread_Callbacks callbacks_##arch = { \
> + .next_thread = next_thread, \
> + .memory_read = memory_read, \
> + .set_initial_registers = libdw_set_initial_registers_##arch, \
> +}
> +
> +DEFINE_DWFL_THREAD_CALLBACKS(x86);
> +DEFINE_DWFL_THREAD_CALLBACKS(arm);
> +DEFINE_DWFL_THREAD_CALLBACKS(arm64);
> +DEFINE_DWFL_THREAD_CALLBACKS(csky);
> +DEFINE_DWFL_THREAD_CALLBACKS(loongarch);
> +DEFINE_DWFL_THREAD_CALLBACKS(powerpc);
> +DEFINE_DWFL_THREAD_CALLBACKS(riscv);
> +DEFINE_DWFL_THREAD_CALLBACKS(s390);
> +
> +static const Dwfl_Thread_Callbacks *get_thread_callbacks(const char *arch)
> +{
> + if (!strcmp(arch, "arm"))
> + return &callbacks_arm;
> + else if (!strcmp(arch, "arm64"))
> + return &callbacks_arm64;
> + else if (!strcmp(arch, "csky"))
> + return &callbacks_csky;
> + else if (!strcmp(arch, "loongarch"))
> + return &callbacks_loongarch;
> + else if (!strcmp(arch, "powerpc"))
> + return &callbacks_powerpc;
> + else if (!strcmp(arch, "riscv"))
> + return &callbacks_riscv;
> + else if (!strcmp(arch, "s390"))
> + return &callbacks_s390;
> + else if (!strcmp(arch, "x86"))
> + return &callbacks_x86;
> +
> + pr_err("Fail to get thread callbacks for arch %s, returns NULL\n",
> + arch);
> + return NULL;
> +}
>
> static int
> frame_callback(Dwfl_Frame *state, void *arg)
> @@ -278,6 +312,7 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
> const char *arch = perf_env__arch(ui_buf.machine->env);
> Dwarf_Word ip;
> int err = -EINVAL, i;
> + const Dwfl_Thread_Callbacks *callbacks;
>
> if (!data->user_regs || !data->user_regs->regs)
> return -EINVAL;
> @@ -300,7 +335,11 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
> if (err)
> goto out;
>
> - err = !dwfl_attach_state(ui->dwfl, EM_NONE, thread__tid(thread), &callbacks, ui);
> + callbacks = get_thread_callbacks(arch);
> + if (!callbacks)
> + goto out;
> +
> + err = !dwfl_attach_state(ui->dwfl, EM_NONE, thread__tid(thread), callbacks, ui);
> if (err)
> goto out;
>
> diff --git a/tools/perf/util/unwind-libdw.h b/tools/perf/util/unwind-libdw.h
> index 8c88bc4f2304..574b29848cce 100644
> --- a/tools/perf/util/unwind-libdw.h
> +++ b/tools/perf/util/unwind-libdw.h
> @@ -9,7 +9,15 @@ struct machine;
> struct perf_sample;
> struct thread;
>
> -bool libdw__arch_set_initial_registers(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_x86(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_arm(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_arm64(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_csky(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_loongarch(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_mips(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_powerpc(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_riscv(Dwfl_Thread *thread, void *arg);
> +bool libdw_set_initial_registers_s390(Dwfl_Thread *thread, void *arg);
>
> struct unwind_info {
> Dwfl *dwfl;
> --
> 2.52.0.457.g6b5491de43-goog
>