subsys/profiling: relocate stack unwind backends

Relocate stack unwind backends from `arch/` to perf's
`backends/` folder, just like logging/shell/..

Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>

arch/riscv/core/CMakeLists.txt

@@ -27,4 +27,3 @@ zephyr_library_sources_ifdef(CONFIG_USERSPACE userspace.S)
 zephyr_library_sources_ifdef(CONFIG_SEMIHOST semihost.c)
 zephyr_library_sources_ifdef(CONFIG_EXCEPTION_STACK_TRACE stacktrace.c)
 zephyr_linker_sources(ROM_START SORT_KEY 0x0vectors vector_table.ld)
-zephyr_library_sources_ifdef(CONFIG_PROFILING_PERF perf.c)

arch/x86/core/ia32.cmake

@@ -25,8 +25,6 @@ zephyr_library_sources_ifdef(CONFIG_GDBSTUB		ia32/gdbstub.c)
 
 zephyr_library_sources_ifdef(CONFIG_DEBUG_COREDUMP	ia32/coredump.c)
 
-zephyr_library_sources_ifdef(CONFIG_PROFILING_PERF	ia32/perf.c)
-
 zephyr_library_sources_ifdef(
   CONFIG_X86_USE_THREAD_LOCAL_STORAGE
   ia32/tls.c

arch/x86/core/intel64.cmake

@@ -20,4 +20,3 @@ zephyr_library_sources_ifdef(CONFIG_IRQ_OFFLOAD		intel64/irq_offload.c)
 zephyr_library_sources_ifdef(CONFIG_USERSPACE	intel64/userspace.S)
 zephyr_library_sources_ifdef(CONFIG_THREAD_LOCAL_STORAGE	intel64/tls.c)
 zephyr_library_sources_ifdef(CONFIG_DEBUG_COREDUMP	intel64/coredump.c)
-zephyr_library_sources_ifdef(CONFIG_PROFILING_PERF	intel64/perf.c)

subsys/profiling/perf/CMakeLists.txt

@@ -2,4 +2,10 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-zephyr_sources(perf.c)
+add_subdirectory(backends)
+
+zephyr_library()
+
+zephyr_library_sources(
+  perf.c
+)

subsys/profiling/perf/Kconfig

@@ -4,11 +4,9 @@
 
 config PROFILING_PERF
 	bool "Perf support"
-	depends on THREAD_STACK_INFO
 	depends on !SMP
-	depends on FRAME_POINTER
 	depends on SHELL
-	depends on RISCV || X86
+	depends on PROFILING_PERF_HAS_BACKEND
 	help
 	  Enable perf shell command.
 
@@ -21,3 +19,5 @@ config PROFILING_PERF_BUFFER_SIZE
 	  Size of buffer used by perf to save stack trace samples.
 
 endif
+
+rsource "backends/Kconfig"

subsys/profiling/perf/backends/CMakeLists.txt

@@ -0,0 +1,15 @@
+# Copyright (c) 2024 Meta Platforms
+#
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_sources_ifdef(CONFIG_PROFILING_PERF_BACKEND_RISCV
+  perf_riscv.c
+)
+
+zephyr_sources_ifdef(CONFIG_PROFILING_PERF_BACKEND_X86
+  perf_x86.c
+)
+
+zephyr_sources_ifdef(CONFIG_PROFILING_PERF_BACKEND_X86_64
+  perf_x86_64.c
+)

subsys/profiling/perf/backends/Kconfig

@@ -0,0 +1,33 @@
+# Copyright (c) 2024 Meta Platforms
+#
+# SPDX-License-Identifier: Apache-2.0
+
+config PROFILING_PERF_HAS_BACKEND
+	bool
+	help
+	  Selected when there's an implementation for
+	  `arch_perf_current_stack_trace()`
+
+config PROFILING_PERF_BACKEND_RISCV
+	bool
+	default y
+	depends on RISCV
+	depends on THREAD_STACK_INFO
+	depends on FRAME_POINTER
+	select PROFILING_PERF_HAS_BACKEND
+
+config PROFILING_PERF_BACKEND_X86
+	bool
+	default y
+	depends on X86 && !X86_64
+	depends on THREAD_STACK_INFO
+	depends on FRAME_POINTER
+	select PROFILING_PERF_HAS_BACKEND
+
+config PROFILING_PERF_BACKEND_X86_64
+	bool
+	default y
+	depends on X86_64
+	depends on THREAD_STACK_INFO
+	depends on FRAME_POINTER
+	select PROFILING_PERF_HAS_BACKEND