Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1310 insertions, 0 deletions

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
new file mode 100644
index 000000000..4d5993da9
--- /dev/null
+++ b/tools/perf/Makefile.config
@@ -0,0 +1,1310 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+ifeq ($(src-perf),)
+src-perf := $(srctree)/tools/perf
+endif
+
+ifeq ($(obj-perf),)
+obj-perf := $(OUTPUT)
+endif
+
+ifneq ($(obj-perf),)
+obj-perf := $(abspath $(obj-perf))/
+endif
+
+$(shell printf "" > $(OUTPUT).config-detected)
+detected     = $(shell echo "$(1)=y"       >> $(OUTPUT).config-detected)
+detected_var = $(shell echo "$(1)=$($(1))" >> $(OUTPUT).config-detected)
+
+CFLAGS := $(EXTRA_CFLAGS) $(filter-out -Wnested-externs,$(EXTRA_WARNINGS))
+HOSTCFLAGS := $(filter-out -Wnested-externs,$(EXTRA_WARNINGS))
+
+# This is required because the kernel is built with this and some of the code
+# borrowed from kernel headers depends on it, e.g. put_unaligned_*().
+CFLAGS += -fno-strict-aliasing
+
+# Set target flag and options when using clang as compiler.
+ifeq ($(CC_NO_CLANG), 0)
+  CLANG_TARGET_FLAGS_arm	:= arm-linux-gnueabi
+  CLANG_TARGET_FLAGS_arm64	:= aarch64-linux-gnu
+  CLANG_TARGET_FLAGS_loongarch	:= loongarch64-linux-gnu
+  CLANG_TARGET_FLAGS_m68k	:= m68k-linux-gnu
+  CLANG_TARGET_FLAGS_mips	:= mipsel-linux-gnu
+  CLANG_TARGET_FLAGS_powerpc	:= powerpc64le-linux-gnu
+  CLANG_TARGET_FLAGS_riscv	:= riscv64-linux-gnu
+  CLANG_TARGET_FLAGS_s390	:= s390x-linux-gnu
+  CLANG_TARGET_FLAGS_x86	:= x86_64-linux-gnu
+  CLANG_TARGET_FLAGS_x86_64	:= x86_64-linux-gnu
+
+  # Default to host architecture if ARCH is not explicitly given.
+  ifeq ($(ARCH), $(HOSTARCH))
+    CLANG_TARGET_FLAGS := $(shell $(CLANG) -print-target-triple)
+  else
+    CLANG_TARGET_FLAGS := $(CLANG_TARGET_FLAGS_$(ARCH))
+  endif
+
+  ifeq ($(CROSS_COMPILE),)
+    ifeq ($(CLANG_TARGET_FLAGS),)
+      $(error Specify CROSS_COMPILE or add CLANG_TARGET_FLAGS for $(ARCH))
+    else
+      CLANG_FLAGS += --target=$(CLANG_TARGET_FLAGS)
+    endif # CLANG_TARGET_FLAGS
+  else
+    CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
+  endif # CROSS_COMPILE
+
+  CC := $(CLANG) $(CLANG_FLAGS) -fintegrated-as
+  CXX := $(CXX) $(CLANG_FLAGS) -fintegrated-as
+
+  # Enabled Wthread-safety analysis for clang builds.
+  CFLAGS += -Wthread-safety
+endif
+
+include $(srctree)/tools/scripts/Makefile.arch
+
+$(call detected_var,SRCARCH)
+
+CFLAGS += -I$(OUTPUT)arch/$(SRCARCH)/include/generated
+
+# Additional ARCH settings for x86
+ifeq ($(SRCARCH),x86)
+  $(call detected,CONFIG_X86)
+  ifeq (${IS_64_BIT}, 1)
+    CFLAGS += -DHAVE_ARCH_X86_64_SUPPORT
+    ARCH_INCLUDE = ../../arch/x86/lib/memcpy_64.S ../../arch/x86/lib/memset_64.S
+    $(call detected,CONFIG_X86_64)
+  endif
+endif
+
+ifeq ($(ARCH),s390)
+  CFLAGS += -fPIC
+  CXXFLAGS += -fPIC
+endif
+
+# Unconditionally set up the libunwind feature build flags as a
+# feature-dump build doesn't specify LIBUNWIND=1. This means that
+# dumping the libunwind features will be broken that can impact later
+# builds that use the feature dump.
+ifeq ($(SRCARCH),arm)
+  LIBUNWIND_LIBS = -lunwind -lunwind-arm
+endif
+ifeq ($(SRCARCH),arm64)
+  LIBUNWIND_LIBS = -lunwind -lunwind-aarch64
+endif
+ifeq ($(SRCARCH),loongarch)
+  LIBUNWIND_LIBS = -lunwind -lunwind-loongarch64
+endif
+ifeq ($(ARCH),mips)
+  LIBUNWIND_LIBS = -lunwind -lunwind-mips
+endif
+ifeq ($(SRCARCH),powerpc)
+  LIBUNWIND_LIBS := -lunwind -lunwind-ppc64
+endif
+ifeq ($(SRCARCH),riscv)
+  LIBUNWIND_LIBS := -lunwind -lunwind-riscv
+endif
+ifeq ($(SRCARCH),s390)
+  LIBUNWIND_LIBS := -lunwind -lunwind-s390x
+endif
+ifeq ($(SRCARCH),x86)
+  ifeq (${IS_64_BIT}, 1)
+    LIBUNWIND_LIBS = -lunwind-x86_64 -lunwind -llzma
+  else
+    LIBUNWIND_LIBS = -lunwind-x86 -lunwind -llzma
+  endif
+endif
+ifneq ($(LIBUNWIND),1)
+  NO_LIBUNWIND := 1
+endif
+ifeq ($(LIBUNWIND_LIBS),)
+  NO_LIBUNWIND := 1
+endif
+
+#
+# For linking with debug library, run like:
+#
+#   make DEBUG=1 LIBUNWIND_DIR=/opt/libunwind/
+#
+LIBUNWIND_ARCHS:=aarch64 arm loongarch64 mips ppc32 ppc64 riscv s390x x86 x86_64
+
+# "Local" (no arch specified) feature test flags.
+FEATURE_CHECK_CFLAGS-libunwind = $(LIBUNWIND_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libunwind = $(LIBUNWIND_LDFLAGS) $(LIBUNWIND_LIBS)
+FEATURE_CHECK_CFLAGS-libunwind-debug-frame = $(LIBUNWIND_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libunwind-debug-frame = $(LIBUNWIND_LDFLAGS) $(LIBUNWIND_LIBS)
+
+# Add directory into the "remote" (build for a a specific arch) feature tests.
+ifdef LIBUNWIND_DIR
+  LIBUNWIND_CFLAGS  = -I$(LIBUNWIND_DIR)/include
+  LIBUNWIND_LDFLAGS = -L$(LIBUNWIND_DIR)/lib
+
+  define libunwind_arch_set_flags
+    FEATURE_CHECK_CFLAGS-libunwind-$(1)  = -I$(LIBUNWIND_DIR)/include
+    FEATURE_CHECK_LDFLAGS-libunwind-$(1) = -L$(LIBUNWIND_DIR)/lib -lunwind -lunwind-$(1)
+  endef
+  $(foreach arch,$(LIBUNWIND_ARCHS), \
+    $(eval $(call libunwind_arch_set_flags,$(arch))) \
+  )
+endif
+
+ifdef CSINCLUDES
+  LIBOPENCSD_CFLAGS := -I$(CSINCLUDES)
+endif
+OPENCSDLIBS := -lopencsd_c_api -lopencsd
+ifeq ($(findstring -static,${LDFLAGS}),-static)
+  OPENCSDLIBS += -lstdc++
+endif
+ifdef CSLIBS
+  LIBOPENCSD_LDFLAGS := -L$(CSLIBS)
+endif
+FEATURE_CHECK_CFLAGS-libopencsd := $(LIBOPENCSD_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libopencsd := $(LIBOPENCSD_LDFLAGS) $(OPENCSDLIBS)
+
+# for linking with debug library, run like:
+# make DEBUG=1 LIBDW_DIR=/opt/libdw/
+ifdef LIBDW_DIR
+  LIBDW_CFLAGS  := -I$(LIBDW_DIR)/include
+  LIBDW_LDFLAGS := -L$(LIBDW_DIR)/lib
+endif
+DWARFLIBS := -ldw
+ifeq ($(findstring -static,${LDFLAGS}),-static)
+  DWARFLIBS += -lelf -lz -llzma -lbz2
+
+  LIBDW_VERSION := $(shell $(PKG_CONFIG) --modversion libdw).0.0
+  LIBDW_VERSION_1 := $(word 1, $(subst ., ,$(LIBDW_VERSION)))
+  LIBDW_VERSION_2 := $(word 2, $(subst ., ,$(LIBDW_VERSION)))
+
+  # Elfutils merged libebl.a into libdw.a starting from version 0.177,
+  # Link libebl.a only if libdw is older than this version.
+  ifeq ($(shell test $(LIBDW_VERSION_2) -lt 177; echo $$?),0)
+    DWARFLIBS += -lebl
+  endif
+
+  # Must put -ldl after -lebl for dependency
+  DWARFLIBS += -ldl
+endif
+FEATURE_CHECK_CFLAGS-libdw := $(LIBDW_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libdw := $(LIBDW_LDFLAGS) $(DWARFLIBS)
+
+ifneq ($(NO_BABELTRACE2),1)
+  ifeq ($(call get-executable,$(PKG_CONFIG)),)
+    $(error Error: $(PKG_CONFIG) needed by babeltrace2 is missing on this system, please install it)
+  endif
+endif
+
+# for linking with debug library, run like:
+# make DEBUG=1 LIBCAPSTONE_DIR=/opt/capstone/
+ifdef LIBCAPSTONE_DIR
+  LIBCAPSTONE_CFLAGS  := -I$(LIBCAPSTONE_DIR)/include
+  LIBCAPSTONE_LDFLAGS := -L$(LIBCAPSTONE_DIR)/
+endif
+FEATURE_CHECK_CFLAGS-libcapstone := $(LIBCAPSTONE_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libcapstone := $(LIBCAPSTONE_LDFLAGS) -lcapstone
+
+ifdef LIBZSTD_DIR
+  LIBZSTD_CFLAGS  := -I$(LIBZSTD_DIR)/lib
+  LIBZSTD_LDFLAGS := -L$(LIBZSTD_DIR)/lib
+endif
+FEATURE_CHECK_CFLAGS-libzstd := $(LIBZSTD_CFLAGS)
+FEATURE_CHECK_LDFLAGS-libzstd := $(LIBZSTD_LDFLAGS)
+
+# for linking with debug library, run like:
+# make DEBUG=1 PKG_CONFIG_PATH=/opt/libtraceevent/(lib|lib64)/pkgconfig
+
+ifneq ($(NO_LIBTRACEEVENT),1)
+  ifeq ($(call get-executable,$(PKG_CONFIG)),)
+    $(error Error: $(PKG_CONFIG) needed by libtraceevent is missing on this system, please install it)
+  endif
+endif
+
+FEATURE_CHECK_CFLAGS-bpf = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi -I$(srctree)/tools/include/uapi
+# include ARCH specific config
+-include $(src-perf)/arch/$(SRCARCH)/Makefile
+
+include $(srctree)/tools/scripts/utilities.mak
+
+ifeq ($(call get-executable,$(FLEX)),)
+  $(error Error: $(FLEX) is missing on this system, please install it)
+endif
+
+ifeq ($(call get-executable,$(BISON)),)
+  $(error Error: $(BISON) is missing on this system, please install it)
+endif
+
+ifneq ($(OUTPUT),)
+  ifeq ($(shell expr $(shell $(BISON) --version | grep bison | sed -e 's/.\+ \([0-9]\+\).\([0-9]\+\).\([0-9]\+\)/\1\2\3/g') \>\= 371), 1)
+    BISON_FILE_PREFIX_MAP := --file-prefix-map=$(OUTPUT)=
+  endif
+endif
+
+# Treat warnings as errors unless directed not to
+ifneq ($(WERROR),0)
+  CORE_CFLAGS += -Werror
+  CXXFLAGS += -Werror
+  HOSTCFLAGS += -Werror
+endif
+
+ifndef DEBUG
+  DEBUG := 0
+endif
+
+ifeq ($(DEBUG),0)
+CORE_CFLAGS += -DNDEBUG=1
+CORE_CFLAGS += -O3
+else
+  CORE_CFLAGS += -g
+  CXXFLAGS += -g
+endif
+
+ifdef PARSER_DEBUG
+  PARSER_DEBUG_BISON := -t
+  PARSER_DEBUG_FLEX  := -d
+  CFLAGS             += -DPARSER_DEBUG
+  $(call detected_var,PARSER_DEBUG_BISON)
+  $(call detected_var,PARSER_DEBUG_FLEX)
+endif
+
+ifdef LTO
+  CORE_CFLAGS += -flto
+  CXXFLAGS += -flto
+endif
+
+# Try different combinations to accommodate systems that only have
+# python[2][3]-config in weird combinations in the following order of
+# priority from lowest to highest:
+#   * python2-config as per pep-0394.
+#   * python-config
+#   * python3-config
+#   * $(PYTHON)-config (If PYTHON is user supplied but PYTHON_CONFIG isn't)
+#
+PYTHON_AUTO := python-config
+PYTHON_AUTO := $(if $(call get-executable,python2-config),python2-config,$(PYTHON_AUTO))
+PYTHON_AUTO := $(if $(call get-executable,python-config),python-config,$(PYTHON_AUTO))
+PYTHON_AUTO := $(if $(call get-executable,python3-config),python3-config,$(PYTHON_AUTO))
+
+# If PYTHON is defined but PYTHON_CONFIG isn't, then take $(PYTHON)-config as if it was the user
+# supplied value for PYTHON_CONFIG. Because it's "user supplied", error out if it doesn't exist.
+ifdef PYTHON
+  ifndef PYTHON_CONFIG
+    PYTHON_CONFIG_AUTO := $(call get-executable,$(PYTHON)-config)
+    PYTHON_CONFIG := $(if $(PYTHON_CONFIG_AUTO),$(PYTHON_CONFIG_AUTO),\
+                          $(call $(error $(PYTHON)-config not found)))
+  endif
+endif
+
+# Select either auto detected python and python-config or use user supplied values if they are
+# defined. get-executable-or-default fails with an error if the first argument is supplied but
+# doesn't exist.
+override PYTHON_CONFIG := $(call get-executable-or-default,PYTHON_CONFIG,$(PYTHON_AUTO))
+override PYTHON := $(call get-executable-or-default,PYTHON,$(subst -config,,$(PYTHON_CONFIG)))
+
+grep-libs  = $(filter -l%,$(1))
+strip-libs  = $(filter-out -l%,$(1))
+
+PYTHON_CONFIG_SQ := $(call shell-sq,$(PYTHON_CONFIG))
+
+# Python 3.8 changed the output of `python-config --ldflags` to not include the
+# '-lpythonX.Y' flag unless '--embed' is also passed. The feature check for
+# libpython fails if that flag is not included in LDFLAGS
+ifeq ($(shell $(PYTHON_CONFIG_SQ) --ldflags --embed 2>&1 1>/dev/null; echo $$?), 0)
+  PYTHON_CONFIG_LDFLAGS := --ldflags --embed
+else
+  PYTHON_CONFIG_LDFLAGS := --ldflags
+endif
+
+ifdef PYTHON_CONFIG
+  PYTHON_EMBED_LDOPTS := $(shell $(PYTHON_CONFIG_SQ) $(PYTHON_CONFIG_LDFLAGS) 2>/dev/null)
+  # Update the python flags for cross compilation
+  ifdef CROSS_COMPILE
+    PYTHON_NATIVE := $(shell echo $(PYTHON_EMBED_LDOPTS) | sed 's/\(-L.*\/\)\(.*-linux-gnu\).*/\2/')
+    PYTHON_EMBED_LDOPTS := $(subst $(PYTHON_NATIVE),$(shell $(CC) -dumpmachine),$(PYTHON_EMBED_LDOPTS))
+  endif
+  PYTHON_EMBED_LDFLAGS := $(call strip-libs,$(PYTHON_EMBED_LDOPTS))
+  PYTHON_EMBED_LIBADD := $(call grep-libs,$(PYTHON_EMBED_LDOPTS)) -lutil
+  PYTHON_EMBED_CCOPTS := $(shell $(PYTHON_CONFIG_SQ) --includes 2>/dev/null)
+  FLAGS_PYTHON_EMBED := $(PYTHON_EMBED_CCOPTS) $(PYTHON_EMBED_LDOPTS)
+  ifeq ($(CC_NO_CLANG), 0)
+    PYTHON_EMBED_CCOPTS := $(filter-out -ffat-lto-objects, $(PYTHON_EMBED_CCOPTS))
+  endif
+endif
+
+FEATURE_CHECK_CFLAGS-libpython := $(PYTHON_EMBED_CCOPTS)
+FEATURE_CHECK_LDFLAGS-libpython := $(PYTHON_EMBED_LDOPTS)
+
+FEATURE_CHECK_LDFLAGS-libaio = -lrt
+
+CORE_CFLAGS += -fno-omit-frame-pointer
+CORE_CFLAGS += -Wall
+CORE_CFLAGS += -Wextra
+CORE_CFLAGS += -std=gnu11
+CORE_CFLAGS += -funsigned-char
+
+CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
+CXXFLAGS += -Wall
+CXXFLAGS += -Wextra
+CXXFLAGS += -fno-omit-frame-pointer
+
+HOSTCFLAGS += -Wall
+HOSTCFLAGS += -Wextra
+
+# Enforce a non-executable stack, as we may regress (again) in the future by
+# adding assembler files missing the .GNU-stack linker note.
+LDFLAGS += -Wl,-z,noexecstack
+
+EXTLIBS = -lpthread -lrt -lm -ldl
+
+ifneq ($(TCMALLOC),)
+  CFLAGS += -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-free
+  EXTLIBS += -ltcmalloc
+endif
+
+ifeq ($(FEATURES_DUMP),)
+# We will display at the end of this Makefile.config, using $(call feature_display_entries),
+# as we may retry some feature detection here.
+  FEATURE_DISPLAY_DEFERRED := 1
+include $(srctree)/tools/build/Makefile.feature
+else
+include $(FEATURES_DUMP)
+endif
+
+ifeq ($(feature-stackprotector-all), 1)
+  CORE_CFLAGS += -fstack-protector-all
+endif
+
+ifeq ($(DEBUG),0)
+  ifeq ($(feature-fortify-source), 1)
+    CORE_CFLAGS += -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2
+  endif
+endif
+
+INC_FLAGS += -I$(src-perf)/util/include
+INC_FLAGS += -I$(src-perf)/arch/$(SRCARCH)/include
+INC_FLAGS += -I$(srctree)/tools/include/
+INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/uapi
+INC_FLAGS += -I$(srctree)/tools/include/uapi
+INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/include/
+INC_FLAGS += -I$(srctree)/tools/arch/$(SRCARCH)/
+
+# $(obj-perf)      for generated common-cmds.h
+# $(obj-perf)/util for generated bison/flex headers
+ifneq ($(OUTPUT),)
+INC_FLAGS += -I$(obj-perf)/util
+INC_FLAGS += -I$(obj-perf)
+endif
+
+INC_FLAGS += -I$(src-perf)/util
+INC_FLAGS += -I$(src-perf)
+
+CORE_CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE
+
+CFLAGS   += $(CORE_CFLAGS) $(INC_FLAGS)
+CXXFLAGS += $(INC_FLAGS)
+
+LIBPERF_CFLAGS := $(CORE_CFLAGS) $(EXTRA_CFLAGS)
+
+ifeq ($(feature-pthread-attr-setaffinity-np), 1)
+  CFLAGS += -DHAVE_PTHREAD_ATTR_SETAFFINITY_NP
+endif
+
+ifeq ($(feature-pthread-barrier), 1)
+  CFLAGS += -DHAVE_PTHREAD_BARRIER
+endif
+
+ifndef NO_BIONIC
+  $(call feature_check,bionic)
+  ifeq ($(feature-bionic), 1)
+    BIONIC := 1
+    CFLAGS += -DLACKS_SIGQUEUE_PROTOTYPE
+    CFLAGS += -DLACKS_OPEN_MEMSTREAM_PROTOTYPE
+    EXTLIBS := $(filter-out -lrt,$(EXTLIBS))
+    EXTLIBS := $(filter-out -lpthread,$(EXTLIBS))
+  endif
+endif
+
+ifeq ($(feature-eventfd), 1)
+  CFLAGS += -DHAVE_EVENTFD_SUPPORT
+endif
+
+ifeq ($(feature-gettid), 1)
+  CFLAGS += -DHAVE_GETTID
+endif
+
+ifeq ($(feature-file-handle), 1)
+  CFLAGS += -DHAVE_FILE_HANDLE
+endif
+
+ifdef NO_LIBELF
+  NO_LIBDW := 1
+  NO_LIBUNWIND := 1
+  NO_LIBBPF := 1
+  NO_JVMTI := 1
+else
+  ifeq ($(feature-libelf), 0)
+    ifeq ($(feature-glibc), 1)
+      LIBC_SUPPORT := 1
+    endif
+    ifeq ($(BIONIC),1)
+      LIBC_SUPPORT := 1
+    endif
+    ifeq ($(LIBC_SUPPORT),1)
+      $(error ERROR: No libelf found. Disables 'probe' tool, jvmti and BPF support. Please install libelf-dev, libelf-devel, elfutils-libelf-devel or build with NO_LIBELF=1.)
+    else
+      ifneq ($(filter s% -fsanitize=address%,$(EXTRA_CFLAGS),),)
+        ifneq ($(shell ldconfig -p | grep libasan >/dev/null 2>&1; echo $$?), 0)
+          $(error No libasan found, please install libasan)
+        endif
+      endif
+
+      ifneq ($(filter s% -fsanitize=undefined%,$(EXTRA_CFLAGS),),)
+        ifneq ($(shell ldconfig -p | grep libubsan >/dev/null 2>&1; echo $$?), 0)
+          $(error No libubsan found, please install libubsan)
+        endif
+      endif
+
+      ifneq ($(filter s% -static%,$(LDFLAGS),),)
+        $(error No static glibc found, please install glibc-static)
+      else
+        $(error No gnu/libc-version.h found, please install glibc-dev[el])
+      endif
+    endif
+  else
+    ifneq ($(feature-libdw), 1)
+      ifndef NO_LIBDW
+        $(warning No libdw.h found or old libdw.h found or elfutils is older than 0.157, disables dwarf support. Please install new elfutils-devel/libdw-dev)
+        NO_LIBDW := 1
+      endif
+    endif # Dwarf support
+  endif # libelf support
+endif # NO_LIBELF
+
+ifeq ($(feature-libaio), 1)
+  ifndef NO_AIO
+    CFLAGS += -DHAVE_AIO_SUPPORT
+  endif
+endif
+
+ifeq ($(feature-scandirat), 1)
+  # Ignore having scandirat with memory sanitizer that lacks an interceptor.
+  ifeq ($(filter s% -fsanitize=memory%,$(EXTRA_CFLAGS),),)
+    CFLAGS += -DHAVE_SCANDIRAT_SUPPORT
+  endif
+endif
+
+ifeq ($(feature-sched_getcpu), 1)
+  CFLAGS += -DHAVE_SCHED_GETCPU_SUPPORT
+endif
+
+ifeq ($(feature-setns), 1)
+  CFLAGS += -DHAVE_SETNS_SUPPORT
+  $(call detected,CONFIG_SETNS)
+endif
+
+ifeq ($(feature-reallocarray), 0)
+  CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
+endif
+
+ifdef CORESIGHT
+  $(call feature_check,libopencsd)
+  ifeq ($(feature-libopencsd), 1)
+    CFLAGS += -DHAVE_CSTRACE_SUPPORT $(LIBOPENCSD_CFLAGS)
+    LDFLAGS += $(LIBOPENCSD_LDFLAGS)
+    EXTLIBS += $(OPENCSDLIBS)
+    $(call detected,CONFIG_LIBOPENCSD)
+    ifdef CSTRACE_RAW
+      CFLAGS += -DCS_DEBUG_RAW
+      ifeq (${CSTRACE_RAW}, packed)
+        CFLAGS += -DCS_RAW_PACKED
+      endif
+    endif
+  else
+    $(error Error: No libopencsd library found or the version is not up-to-date. Please install recent libopencsd to build with CORESIGHT=1)
+  endif
+endif
+
+ifndef NO_ZLIB
+  ifeq ($(feature-zlib), 1)
+    CFLAGS += -DHAVE_ZLIB_SUPPORT
+    EXTLIBS += -lz
+    $(call detected,CONFIG_ZLIB)
+  else
+    NO_ZLIB := 1
+  endif
+endif
+
+ifndef NO_LIBELF
+  CFLAGS += -DHAVE_LIBELF_SUPPORT
+  EXTLIBS += -lelf
+  $(call detected,CONFIG_LIBELF)
+
+  ifeq ($(feature-libelf-getphdrnum), 1)
+    CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
+  endif
+
+  ifeq ($(feature-libelf-gelf_getnote), 1)
+    CFLAGS += -DHAVE_GELF_GETNOTE_SUPPORT
+  else
+    $(warning gelf_getnote() not found on libelf, SDT support disabled)
+  endif
+
+  ifeq ($(feature-libelf-getshdrstrndx), 1)
+    CFLAGS += -DHAVE_ELF_GETSHDRSTRNDX_SUPPORT
+  endif
+
+  ifeq ($(feature-libelf-zstd), 1)
+    ifdef NO_LIBZSTD
+      $(error Error: libzstd is required by libelf, please do not set NO_LIBZSTD)
+    endif
+  endif
+
+  ifndef NO_LIBDEBUGINFOD
+    $(call feature_check,libdebuginfod)
+    ifeq ($(feature-libdebuginfod), 1)
+      CFLAGS += -DHAVE_DEBUGINFOD_SUPPORT
+      EXTLIBS += -ldebuginfod
+    else
+      $(warning No elfutils/debuginfod.h found, no debuginfo server support, please install libdebuginfod-dev/elfutils-debuginfod-client-devel or equivalent)
+    endif
+  endif
+
+  ifndef NO_LIBDW
+    CFLAGS += -DHAVE_LIBDW_SUPPORT $(LIBDW_CFLAGS)
+    LDFLAGS += $(LIBDW_LDFLAGS)
+    EXTLIBS += ${DWARFLIBS}
+    $(call detected,CONFIG_LIBDW)
+  endif # NO_LIBDW
+
+  ifndef NO_LIBBPF
+    ifeq ($(feature-bpf), 1)
+      ifdef LIBBPF_DYNAMIC
+        $(call feature_check,libbpf)
+        ifeq ($(feature-libbpf), 1)
+          EXTLIBS += -lbpf
+          CFLAGS += -DHAVE_LIBBPF_SUPPORT
+          $(call detected,CONFIG_LIBBPF)
+          $(call detected,CONFIG_LIBBPF_DYNAMIC)
+        else
+          $(error Error: No libbpf devel library found or older than v1.0, please install/update libbpf-devel)
+        endif
+      else
+        ifeq ($(NO_ZLIB), 1)
+          $(warning Warning: Statically building libbpf not possible as zlib is missing)
+          NO_LIBBPF := 1
+        else
+          # Libbpf will be built as a static library from tools/lib/bpf.
+          LIBBPF_STATIC := 1
+          $(call detected,CONFIG_LIBBPF)
+          CFLAGS += -DHAVE_LIBBPF_SUPPORT
+	  LIBBPF_INCLUDE = $(LIBBPF_DIR)/..
+        endif
+      endif
+    endif
+  endif # NO_LIBBPF
+endif # NO_LIBELF
+
+ifndef NO_SDT
+  ifneq ($(feature-sdt), 1)
+    $(warning No sys/sdt.h found, no SDT events are defined, please install systemtap-sdt-devel or systemtap-sdt-dev)
+    NO_SDT := 1;
+  else
+    CFLAGS += -DHAVE_SDT_EVENT
+    $(call detected,CONFIG_SDT_EVENT)
+  endif
+endif
+
+ifdef PERF_HAVE_JITDUMP
+  ifndef NO_LIBELF
+    $(call detected,CONFIG_JITDUMP)
+    CFLAGS += -DHAVE_JITDUMP
+  endif
+endif
+
+ifeq ($(SRCARCH),powerpc)
+  ifndef NO_LIBDW
+    CFLAGS += -DHAVE_SKIP_CALLCHAIN_IDX
+  endif
+endif
+
+ifndef NO_LIBBPF
+  ifneq ($(feature-bpf), 1)
+    $(warning BPF API too old. Please install recent kernel headers. BPF support in 'perf record' is disabled.)
+    NO_LIBBPF := 1
+  endif
+endif
+
+ifeq ($(feature-libopenssl), 1)
+  $(call detected,CONFIG_LIBOPENSSL)
+  CFLAGS += -DHAVE_LIBOPENSSL_SUPPORT
+endif
+
+ifndef BUILD_BPF_SKEL
+  # BPF skeletons control a large number of perf features, by default
+  # they are enabled.
+  BUILD_BPF_SKEL := 1
+endif
+
+ifeq ($(BUILD_BPF_SKEL),1)
+  ifeq ($(filter -DHAVE_LIBELF_SUPPORT, $(CFLAGS)),)
+    $(warning Warning: Disabled BPF skeletons as libelf is required by bpftool)
+    BUILD_BPF_SKEL := 0
+  else ifeq ($(filter -DHAVE_ZLIB_SUPPORT, $(CFLAGS)),)
+    $(warning Warning: Disabled BPF skeletons as zlib is required by bpftool)
+    BUILD_BPF_SKEL := 0
+  else ifeq ($(filter -DHAVE_LIBBPF_SUPPORT, $(CFLAGS)),)
+    $(warning Warning: Disabled BPF skeletons as libbpf is required)
+    BUILD_BPF_SKEL := 0
+  else ifeq ($(filter -DHAVE_LIBOPENSSL_SUPPORT, $(CFLAGS)),)
+    $(warning Warning: Disabled BPF skeletons as libopenssl is required)
+    BUILD_BPF_SKEL := 0
+  else ifeq ($(call get-executable,$(CLANG)),)
+    $(warning Warning: Disabled BPF skeletons as clang ($(CLANG)) is missing)
+    BUILD_BPF_SKEL := 0
+  else
+    CLANG_VERSION := $(shell $(CLANG) --version | head -1 | sed 's/.*clang version \([[:digit:]]\+.[[:digit:]]\+.[[:digit:]]\+\).*/\1/g')
+    ifeq ($(call version-lt3,$(CLANG_VERSION),12.0.1),1)
+      $(warning Warning: Disabled BPF skeletons as reliable BTF generation needs at least $(CLANG) version 12.0.1)
+      BUILD_BPF_SKEL := 0
+    endif
+  endif
+  ifeq ($(BUILD_BPF_SKEL),1)
+    $(call feature_check,clang-bpf-co-re)
+    ifeq ($(feature-clang-bpf-co-re), 0)
+      $(warning Warning: Disabled BPF skeletons as clang is too old)
+      BUILD_BPF_SKEL := 0
+    endif
+  endif
+  ifeq ($(BUILD_BPF_SKEL),1)
+    $(call detected,CONFIG_PERF_BPF_SKEL)
+    CFLAGS += -DHAVE_BPF_SKEL
+  endif
+endif
+
+ifndef GEN_VMLINUX_H
+  VMLINUX_H_FILE=$(src-perf)/util/bpf_skel/vmlinux/vmlinux.h
+endif
+
+ifndef NO_LIBUNWIND
+  have_libunwind :=
+
+  $(call feature_check,libunwind)
+  ifneq ($(feature-libunwind), 1)
+    $(warning No libunwind found. Please install libunwind-dev[el] >= 1.1 and/or set LIBUNWIND_DIR and set LIBUNWIND=1 in the make command line as it is opt-in now)
+    NO_LOCAL_LIBUNWIND := 1
+  else
+    have_libunwind := 1
+    $(call detected,CONFIG_LOCAL_LIBUNWIND)
+    CFLAGS  += -DHAVE_LIBUNWIND_SUPPORT
+    CFLAGS  += $(LIBUNWIND_CFLAGS)
+    LDFLAGS += $(LIBUNWIND_LDFLAGS)
+    EXTLIBS_LIBUNWIND := $(LIBUNWIND_LIBS)
+    $(call feature_check,libunwind-debug-frame)
+    ifneq ($(feature-libunwind-debug-frame), 1)
+      CFLAGS += -DNO_LIBUNWIND_DEBUG_FRAME
+    endif
+  endif
+
+  define PROCESS_REMOTE_LIBUNWIND_ARCH
+    $(call feature_check,libunwind-$(1))
+
+    ifeq ($$(feature-libunwind-$(1)), 1)
+      upper_arch := $$(shell echo $(1) | tr '[:lower:]' '[:upper:]')
+      $$(call detected,CONFIG_LIBUNWIND_$$(upper_arch))
+
+      CFLAGS += -DHAVE_LIBUNWIND_$$(upper_arch)_SUPPORT
+      LDFLAGS += -lunwind-$(1)
+      EXTLIBS_LIBUNWIND += -lunwind-$(1)
+      have_libunwind := 1
+
+      $$(call feature_check,libunwind-debug-frame-$(1))
+      ifneq ($$(feature-libunwind-debug-frame-$(1)), 1)
+        CFLAGS += -DNO_LIBUNWIND_DEBUG_FRAME_$$(upper_arch)
+      endif
+    endif
+  endef
+  $(foreach arch,$(LIBUNWIND_ARCHS), \
+    $(eval $(call PROCESS_REMOTE_LIBUNWIND_ARCH,$(arch))) \
+  )
+
+  EXTLIBS += $(EXTLIBS_LIBUNWIND)
+
+  ifeq ($(findstring -static,${LDFLAGS}),-static)
+    # gcc -static links libgcc_eh which contains piece of libunwind
+    LIBUNWIND_LDFLAGS += -Wl,--allow-multiple-definition
+  endif
+
+  ifneq ($(have_libunwind), 1)
+    NO_LIBUNWIND := 1
+  endif
+endif
+
+dwarf-post-unwind := 1
+dwarf-post-unwind-text := BUG
+
+# setup DWARF post unwinder
+ifdef NO_LIBUNWIND
+  ifdef NO_LIBDW
+    $(warning Disabling post unwind, no support found.)
+    dwarf-post-unwind := 0
+  else
+    dwarf-post-unwind-text := libdw
+    $(call detected,CONFIG_LIBDW_DWARF_UNWIND)
+  endif
+else
+  dwarf-post-unwind-text := libunwind
+  $(call detected,CONFIG_LIBUNWIND)
+endif
+
+ifeq ($(dwarf-post-unwind),1)
+  CFLAGS += -DHAVE_DWARF_UNWIND_SUPPORT
+  $(call detected,CONFIG_DWARF_UNWIND)
+endif
+
+ifneq ($(NO_LIBTRACEEVENT),1)
+  $(call detected,CONFIG_TRACE)
+endif
+
+ifndef NO_SLANG
+  ifneq ($(feature-libslang), 1)
+    $(warning slang not found, disables TUI support. Please install slang-devel, libslang-dev or libslang2-dev)
+    NO_SLANG := 1
+  endif
+  ifndef NO_SLANG
+    CFLAGS += -DHAVE_SLANG_SUPPORT
+    EXTLIBS += -lslang
+    $(call detected,CONFIG_SLANG)
+  endif
+endif
+
+ifdef GTK2
+  FLAGS_GTK2=$(CFLAGS) $(LDFLAGS) $(EXTLIBS) $(shell $(PKG_CONFIG) --libs --cflags gtk+-2.0 2>/dev/null)
+  $(call feature_check,gtk2)
+  ifneq ($(feature-gtk2), 1)
+    $(warning GTK2 not found, disables GTK2 support. Please install gtk2-devel or libgtk2.0-dev)
+    NO_GTK2 := 1
+  else
+    $(call feature_check,gtk2-infobar)
+    ifeq ($(feature-gtk2-infobar), 1)
+      GTK_CFLAGS := -DHAVE_GTK_INFO_BAR_SUPPORT
+    endif
+    CFLAGS += -DHAVE_GTK2_SUPPORT
+    GTK_CFLAGS += $(shell $(PKG_CONFIG) --cflags gtk+-2.0 2>/dev/null)
+    GTK_LIBS := $(shell $(PKG_CONFIG) --libs gtk+-2.0 2>/dev/null)
+    EXTLIBS += -ldl
+  endif
+endif
+
+ifdef LIBPERL
+  PERL_EMBED_LDOPTS = $(shell perl -MExtUtils::Embed -e ldopts 2>/dev/null)
+  PERL_EMBED_LDFLAGS = $(call strip-libs,$(PERL_EMBED_LDOPTS))
+  PERL_EMBED_LIBADD = $(call grep-libs,$(PERL_EMBED_LDOPTS))
+  PERL_EMBED_CCOPTS = $(shell perl -MExtUtils::Embed -e ccopts 2>/dev/null)
+  PERL_EMBED_CCOPTS := $(filter-out -specs=%,$(PERL_EMBED_CCOPTS))
+  PERL_EMBED_CCOPTS := $(filter-out -flto% -ffat-lto-objects, $(PERL_EMBED_CCOPTS))
+  PERL_EMBED_LDOPTS := $(filter-out -specs=%,$(PERL_EMBED_LDOPTS))
+  FLAGS_PERL_EMBED=$(PERL_EMBED_CCOPTS) $(PERL_EMBED_LDOPTS)
+
+  $(call feature_check,libperl)
+  ifneq ($(feature-libperl), 1)
+    $(error Missing perl devel files. Please install perl-ExtUtils-Embed/libperl-dev)
+  else
+    LDFLAGS += $(PERL_EMBED_LDFLAGS)
+    EXTLIBS += $(PERL_EMBED_LIBADD)
+    CFLAGS += -DHAVE_LIBPERL_SUPPORT
+    $(call detected,CONFIG_LIBPERL)
+  endif
+endif
+
+ifeq ($(feature-timerfd), 1)
+  CFLAGS += -DHAVE_TIMERFD_SUPPORT
+else
+  $(warning No timerfd support. Disables 'perf kvm stat live')
+endif
+
+disable-python = $(eval $(disable-python_code))
+define disable-python_code
+  CFLAGS += -DNO_LIBPYTHON
+  $(warning $1)
+  NO_LIBPYTHON := 1
+endef
+
+PYTHON_EXTENSION_SUFFIX := '.so'
+ifdef NO_LIBPYTHON
+  $(call disable-python,Python support disabled by user)
+else
+
+  ifndef PYTHON
+    $(call disable-python,No python interpreter was found: disables Python support - please install python-devel/python-dev)
+  else
+    PYTHON_WORD := $(call shell-wordify,$(PYTHON))
+
+    ifndef PYTHON_CONFIG
+      $(call disable-python,No 'python-config' tool was found: disables Python support - please install python-devel/python-dev)
+    else
+
+      ifneq ($(feature-libpython), 1)
+        $(call disable-python,No 'Python.h' was found: disables Python support - please install python-devel/python-dev)
+      else
+         LDFLAGS += $(PYTHON_EMBED_LDFLAGS)
+         EXTLIBS += $(PYTHON_EMBED_LIBADD)
+         PYTHON_SETUPTOOLS_INSTALLED := $(shell $(PYTHON) -c 'import setuptools;' 2> /dev/null && echo "yes" || echo "no")
+         ifeq ($(PYTHON_SETUPTOOLS_INSTALLED), yes)
+           PYTHON_EXTENSION_SUFFIX := $(shell $(PYTHON) -c 'from importlib import machinery; print(machinery.EXTENSION_SUFFIXES[0])')
+           ifdef CROSS_COMPILE
+             PYTHON_EXTENSION_SUFFIX := $(subst $(PYTHON_NATIVE),$(shell $(CC) -dumpmachine),$(PYTHON_EXTENSION_SUFFIX))
+           endif
+           LANG_BINDINGS += $(obj-perf)python/perf$(PYTHON_EXTENSION_SUFFIX)
+	 else
+           $(warning Missing python setuptools, the python binding won't be built, please install python3-setuptools or equivalent)
+         endif
+         CFLAGS += -DHAVE_LIBPYTHON_SUPPORT
+         $(call detected,CONFIG_LIBPYTHON)
+         ifeq ($(filter -fPIC,$(CFLAGS)),)
+           # Building a shared library requires position independent code.
+           CFLAGS += -fPIC
+           CXXFLAGS += -fPIC
+         endif
+      endif
+    endif
+  endif
+endif
+
+ifneq ($(NO_JEVENTS),1)
+  ifeq ($(wildcard pmu-events/arch/$(SRCARCH)/mapfile.csv),)
+    NO_JEVENTS := 1
+  endif
+endif
+ifneq ($(NO_JEVENTS),1)
+  NO_JEVENTS := 0
+  ifndef PYTHON
+    $(error ERROR: No python interpreter needed for jevents generation. Install python or build with NO_JEVENTS=1.)
+  else
+    # jevents.py uses f-strings present in Python 3.6 released in Dec. 2016.
+    JEVENTS_PYTHON_GOOD := $(shell $(PYTHON) -c 'import sys;print("1" if(sys.version_info.major >= 3 and sys.version_info.minor >= 6) else "0")' 2> /dev/null)
+    ifneq ($(JEVENTS_PYTHON_GOOD), 1)
+      $(error ERROR: Python interpreter needed for jevents generation too old (older than 3.6). Install a newer python or build with NO_JEVENTS=1.)
+    endif
+  endif
+endif
+
+ifdef BUILD_NONDISTRO
+  # call all detections now so we get correct status in VF output
+  $(call feature_check,libbfd)
+  $(call feature_check,disassembler-four-args)
+  $(call feature_check,disassembler-init-styled)
+  $(call feature_check,libbfd-threadsafe)
+  $(call feature_check,libbfd-liberty)
+  $(call feature_check,libbfd-liberty-z)
+
+  ifneq ($(feature-libbfd-threadsafe), 1)
+    $(error binutils-dev(el) 2.42 or later is required for non-distro builds)
+  endif
+
+  # we may be on a system that requires -liberty and (maybe) -lz
+  # to link against -lbfd; test each case individually here
+  ifeq ($(feature-libbfd), 1)
+    EXTLIBS += -lbfd -lopcodes
+  else ifeq ($(feature-libbfd-liberty), 1)
+    EXTLIBS += -lbfd -lopcodes -liberty
+  else ifeq ($(feature-libbfd-liberty-z), 1)
+    EXTLIBS += -lbfd -lopcodes -liberty -lz
+  endif
+
+  CFLAGS += -DHAVE_LIBBFD_SUPPORT
+  CXXFLAGS += -DHAVE_LIBBFD_SUPPORT
+  $(call detected,CONFIG_LIBBFD)
+
+  ifeq ($(feature-disassembler-four-args), 1)
+    CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
+  endif
+
+  ifeq ($(feature-disassembler-init-styled), 1)
+    CFLAGS += -DDISASM_INIT_STYLED
+  endif
+endif
+
+ifndef NO_LIBLLVM
+  $(call feature_check,llvm-perf)
+  ifeq ($(feature-llvm-perf), 1)
+    CFLAGS += -DHAVE_LIBLLVM_SUPPORT
+    LLVM_CFLAGS := $(shell $(LLVM_CONFIG) --cflags 2>/dev/null)
+    LLVM_CXXFLAGS := $(shell $(LLVM_CONFIG) --cxxflags 2>/dev/null)
+    LLVM_LIBLLVM := $(shell $(LLVM_CONFIG) --libs all 2>/dev/null) $(shell $(LLVM_CONFIG) --system-libs 2>/dev/null)
+    LLVM_LIBDIR := $(shell $(LLVM_CONFIG) --libdir 2>/dev/null)
+    CFLAGS += $(LLVM_CFLAGS)
+    CXXFLAGS += -DHAVE_LIBLLVM_SUPPORT $(LLVM_CXXFLAGS)
+    LIBLLVM := $(LLVM_LIBLLVM)
+    EXTLIBS += -L$(LLVM_LIBDIR) $(LIBLLVM)
+    EXTLIBS += -lstdc++
+    $(call detected,CONFIG_LIBLLVM)
+  else
+    $(warning No libllvm 13+ found, slower source file resolution, please install llvm-devel/llvm-dev)
+    NO_LIBLLVM := 1
+  endif
+endif
+
+ifndef NO_DEMANGLE
+  $(call feature_check,cxa-demangle)
+  ifeq ($(feature-cxa-demangle), 1)
+    EXTLIBS += -lstdc++
+    CFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
+    CXXFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
+    $(call detected,CONFIG_CXX_DEMANGLE)
+  endif
+  ifdef BUILD_NONDISTRO
+    ifeq ($(filter -liberty,$(EXTLIBS)),)
+      $(call feature_check,cplus-demangle)
+      ifeq ($(feature-cplus-demangle), 1)
+        EXTLIBS += -liberty
+      endif
+    endif
+    ifneq ($(filter -liberty,$(EXTLIBS)),)
+      CFLAGS += -DHAVE_CPLUS_DEMANGLE_SUPPORT
+      CXXFLAGS += -DHAVE_CPLUS_DEMANGLE_SUPPORT
+    endif
+  endif
+endif
+
+ifndef NO_LZMA
+  ifeq ($(feature-lzma), 1)
+    CFLAGS += -DHAVE_LZMA_SUPPORT
+    EXTLIBS += -llzma
+    $(call detected,CONFIG_LZMA)
+  else
+    $(warning No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev)
+    NO_LZMA := 1
+  endif
+endif
+
+ifndef NO_LIBZSTD
+  ifeq ($(feature-libzstd), 1)
+    CFLAGS += -DHAVE_ZSTD_SUPPORT
+    CFLAGS += $(LIBZSTD_CFLAGS)
+    LDFLAGS += $(LIBZSTD_LDFLAGS)
+    EXTLIBS += -lzstd
+    $(call detected,CONFIG_ZSTD)
+  else
+    $(warning No libzstd found, disables trace compression, please install libzstd-dev[el] and/or set LIBZSTD_DIR)
+    NO_LIBZSTD := 1
+  endif
+endif
+
+ifndef NO_BACKTRACE
+  ifeq ($(feature-backtrace), 1)
+    CFLAGS += -DHAVE_BACKTRACE_SUPPORT
+  endif
+endif
+
+ifndef NO_LIBNUMA
+  ifeq ($(feature-libnuma), 0)
+    $(warning No numa.h found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev)
+    NO_LIBNUMA := 1
+  else
+    ifeq ($(feature-numa_num_possible_cpus), 0)
+      $(warning Old numa library found, disables 'perf bench numa mem' benchmark, please install numactl-devel/libnuma-devel/libnuma-dev >= 2.0.8)
+      NO_LIBNUMA := 1
+    else
+      CFLAGS += -DHAVE_LIBNUMA_SUPPORT
+      EXTLIBS += -lnuma
+      $(call detected,CONFIG_NUMA)
+    endif
+  endif
+endif
+
+ifeq (${IS_64_BIT}, 1)
+  ifndef NO_PERF_READ_VDSO32
+    $(call feature_check,compile-32)
+    ifeq ($(feature-compile-32), 1)
+      CFLAGS += -DHAVE_PERF_READ_VDSO32
+    else
+      NO_PERF_READ_VDSO32 := 1
+    endif
+  endif
+  ifneq ($(SRCARCH), x86)
+    NO_PERF_READ_VDSOX32 := 1
+  endif
+  ifndef NO_PERF_READ_VDSOX32
+    $(call feature_check,compile-x32)
+    ifeq ($(feature-compile-x32), 1)
+      CFLAGS += -DHAVE_PERF_READ_VDSOX32
+    else
+      NO_PERF_READ_VDSOX32 := 1
+    endif
+  endif
+else
+  NO_PERF_READ_VDSO32 := 1
+  NO_PERF_READ_VDSOX32 := 1
+endif
+
+ifndef NO_BABELTRACE2
+  $(call feature_check,babeltrace2-ctf-writer)
+  ifeq ($(feature-babeltrace2-ctf-writer), 1)
+    CFLAGS += -DHAVE_BABELTRACE2_CTF_WRITER_SUPPORT $(shell $(PKG_CONFIG) --cflags babeltrace2-ctf-writer)
+    LDFLAGS += $(shell $(PKG_CONFIG) --libs-only-L babeltrace2-ctf-writer)
+    EXTLIBS += $(shell $(PKG_CONFIG) --libs-only-l babeltrace2-ctf-writer)
+    $(call detected,CONFIG_BABELTRACE2_CTF_WRITER)
+  else
+    $(warning No babeltrace2 found, disables 'perf data' CTF format support, please install libbabeltrace2-dev[el])
+  endif
+endif
+
+ifndef NO_CAPSTONE
+  $(call feature_check,libcapstone)
+  ifeq ($(feature-libcapstone), 1)
+    CFLAGS += -DHAVE_LIBCAPSTONE_SUPPORT $(LIBCAPSTONE_CFLAGS)
+    ifdef LIBCAPSTONE_DLOPEN
+      CFLAGS += -DLIBCAPSTONE_DLOPEN
+    else
+      LDFLAGS += $(LIBCAPSTONE_LDFLAGS)
+      EXTLIBS += -lcapstone
+    endif
+    $(call detected,CONFIG_LIBCAPSTONE)
+  else
+    msg := $(warning No libcapstone found, disables disasm engine support for 'perf script', please install libcapstone-dev/capstone-devel);
+  endif
+endif
+
+ifdef EXTRA_TESTS
+    $(call detected,CONFIG_EXTRA_TESTS)
+    CFLAGS += -DHAVE_EXTRA_TESTS
+endif
+
+ifndef NO_JVMTI
+  ifneq (,$(wildcard /usr/sbin/update-java-alternatives))
+    JDIR=$(shell /usr/sbin/update-java-alternatives -l | head -1 | awk '{print $$3}')
+  else
+    ifneq (,$(wildcard /usr/sbin/alternatives))
+      JDIR=$(shell /usr/sbin/alternatives --display java | tail -1 | cut -d' ' -f 5 | sed -e 's%/jre/bin/java.%%g' -e 's%/bin/java.%%g')
+    endif
+  endif
+  ifndef JDIR
+    $(warning No alternatives command found, you need to set JDIR= to point to the root of your Java directory)
+    NO_JVMTI := 1
+  endif
+endif
+
+ifndef NO_JVMTI
+  FEATURE_CHECK_CFLAGS-jvmti := -I$(JDIR)/include -I$(JDIR)/include/linux
+  $(call feature_check,jvmti)
+  ifeq ($(feature-jvmti), 1)
+    $(call detected_var,JDIR)
+    ifndef NO_JVMTI_CMLR
+      FEATURE_CHECK_CFLAGS-jvmti-cmlr := $(FEATURE_CHECK_CFLAGS-jvmti)
+      $(call feature_check,jvmti-cmlr)
+      ifeq ($(feature-jvmti-cmlr), 1)
+        CFLAGS += -DHAVE_JVMTI_CMLR
+      endif
+    endif # NO_JVMTI_CMLR
+  else
+    $(warning No openjdk development package found, please install JDK package, e.g. openjdk-8-jdk, java-latest-openjdk-devel)
+    NO_JVMTI := 1
+  endif
+endif
+
+ifndef NO_LIBPFM4
+  $(call feature_check,libpfm4)
+  ifeq ($(feature-libpfm4), 1)
+    CFLAGS += -DHAVE_LIBPFM
+    EXTLIBS += -lpfm
+    ASCIIDOC_EXTRA = -aHAVE_LIBPFM=1
+    $(call detected,CONFIG_LIBPFM4)
+  else
+    $(warning libpfm4 not found, disables libpfm4 support. Please install libpfm-devel or libpfm4-dev)
+  endif
+endif
+
+# libtraceevent is a recommended dependency picked up from the system.
+ifneq ($(NO_LIBTRACEEVENT),1)
+  ifeq ($(feature-libtraceevent), 1)
+    CFLAGS += -DHAVE_LIBTRACEEVENT $(shell $(PKG_CONFIG) --cflags libtraceevent)
+    LDFLAGS += $(shell $(PKG_CONFIG) --libs-only-L libtraceevent)
+    EXTLIBS += $(shell $(PKG_CONFIG) --libs-only-l libtraceevent)
+    LIBTRACEEVENT_VERSION := $(shell $(PKG_CONFIG) --modversion libtraceevent).0.0
+    LIBTRACEEVENT_VERSION_1 := $(word 1, $(subst ., ,$(LIBTRACEEVENT_VERSION)))
+    LIBTRACEEVENT_VERSION_2 := $(word 2, $(subst ., ,$(LIBTRACEEVENT_VERSION)))
+    LIBTRACEEVENT_VERSION_3 := $(word 3, $(subst ., ,$(LIBTRACEEVENT_VERSION)))
+    LIBTRACEEVENT_VERSION_CPP := $(shell expr $(LIBTRACEEVENT_VERSION_1) \* 255 \* 255 + $(LIBTRACEEVENT_VERSION_2) \* 255 + $(LIBTRACEEVENT_VERSION_3))
+    CFLAGS += -DLIBTRACEEVENT_VERSION=$(LIBTRACEEVENT_VERSION_CPP)
+    $(call detected,CONFIG_LIBTRACEEVENT)
+  else
+    $(error ERROR: libtraceevent is missing. Please install libtraceevent-dev/libtraceevent-devel and/or set LIBTRACEEVENT_DIR or build with NO_LIBTRACEEVENT=1)
+  endif
+endif
+
+ifndef NO_RUST
+  $(call feature_check,rust)
+  ifneq ($(feature-rust), 1)
+    $(warning Rust is not found. Test workloads with rust are disabled.)
+    NO_RUST := 1
+  else
+    NO_RUST := 0
+    CFLAGS += -DHAVE_RUST_SUPPORT
+    $(call detected,CONFIG_RUST_SUPPORT)
+  endif
+
+  ifneq ($(CROSS_COMPILE),)
+    RUST_TARGET_FLAGS_arm	:= arm-unknown-linux-gnueabi
+    RUST_TARGET_FLAGS_arm64	:= aarch64-unknown-linux-gnu
+    RUST_TARGET_FLAGS_loongarch	:= loongarch64-unknown-linux-gnu
+    RUST_TARGET_FLAGS_m68k	:= m68k-unknown-linux-gnu
+    RUST_TARGET_FLAGS_mips	:= mipsel-unknown-linux-gnu
+    RUST_TARGET_FLAGS_powerpc	:= powerpc64le-unknown-linux-gnu
+    RUST_TARGET_FLAGS_riscv	:= riscv64gc-unknown-linux-gnu
+    RUST_TARGET_FLAGS_s390	:= s390x-unknown-linux-gnu
+    RUST_TARGET_FLAGS_x86	:= x86_64-unknown-linux-gnu
+    RUST_TARGET_FLAGS_x86_64	:= x86_64-unknown-linux-gnu
+
+    ifeq ($(RUST_TARGET_FLAGS_$(ARCH)),)
+      $(error Unknown rust cross compilation architecture $(ARCH))
+    endif
+
+    RUST_FLAGS += --target=$(RUST_TARGET_FLAGS_$(ARCH))
+  endif
+endif
+
+# Among the variables below, these:
+#   perfexecdir
+#   libbpf_include_dir
+#   perf_examples_dir
+#   template_dir
+#   mandir
+#   infodir
+#   htmldir
+#   ETC_PERFCONFIG (but not sysconfdir)
+# can be specified as a relative path some/where/else;
+# this is interpreted as relative to $(prefix) and "perf" at
+# runtime figures out where they are based on the path to the executable.
+# This can help installing the suite in a relocatable way.
+
+# Make the path relative to DESTDIR, not to prefix
+ifndef DESTDIR
+prefix ?= $(HOME)
+endif
+bindir_relative = bin
+bindir = $(abspath $(prefix)/$(bindir_relative))
+includedir_relative = include
+includedir = $(abspath $(prefix)/$(includedir_relative))
+mandir = share/man
+infodir = share/info
+perfexecdir = libexec/perf-core
+# FIXME: system's libbpf header directory, where we expect to find bpf/bpf_helpers.h, for instance
+libbpf_include_dir = /usr/include
+perf_examples_dir = lib/perf/examples
+sharedir = $(prefix)/share
+template_dir = share/perf-core/templates
+STRACE_GROUPS_DIR = share/perf-core/strace/groups
+htmldir = share/doc/perf-doc
+tipdir = share/doc/perf-tip
+srcdir = $(srctree)/tools/perf
+ifeq ($(prefix),/usr)
+sysconfdir = /etc
+ETC_PERFCONFIG = $(sysconfdir)/perfconfig
+else
+sysconfdir = $(prefix)/etc
+ETC_PERFCONFIG = etc/perfconfig
+endif
+ifndef lib
+ifeq ($(SRCARCH)$(IS_64_BIT), x861)
+lib = lib64
+else
+lib = lib
+endif
+endif # lib
+libdir = $(prefix)/$(lib)
+
+# Shell quote (do not use $(call) to accommodate ancient setups);
+ETC_PERFCONFIG_SQ = $(subst ','\'',$(ETC_PERFCONFIG))
+STRACE_GROUPS_DIR_SQ = $(subst ','\'',$(STRACE_GROUPS_DIR))
+DESTDIR_SQ = $(subst ','\'',$(DESTDIR))
+bindir_SQ = $(subst ','\'',$(bindir))
+includedir_SQ = $(subst ','\'',$(includedir))
+mandir_SQ = $(subst ','\'',$(mandir))
+infodir_SQ = $(subst ','\'',$(infodir))
+perfexecdir_SQ = $(subst ','\'',$(perfexecdir))
+libbpf_include_dir_SQ = $(subst ','\'',$(libbpf_include_dir))
+perf_examples_dir_SQ = $(subst ','\'',$(perf_examples_dir))
+template_dir_SQ = $(subst ','\'',$(template_dir))
+htmldir_SQ = $(subst ','\'',$(htmldir))
+tipdir_SQ = $(subst ','\'',$(tipdir))
+prefix_SQ = $(subst ','\'',$(prefix))
+sysconfdir_SQ = $(subst ','\'',$(sysconfdir))
+libdir_SQ = $(subst ','\'',$(libdir))
+srcdir_SQ = $(subst ','\'',$(srcdir))
+
+ifneq ($(filter /%,$(firstword $(perfexecdir))),)
+perfexec_instdir = $(perfexecdir)
+perf_include_instdir = $(libbpf_include_dir)
+perf_examples_instdir = $(perf_examples_dir)
+STRACE_GROUPS_INSTDIR = $(STRACE_GROUPS_DIR)
+tip_instdir = $(tipdir)
+else
+perfexec_instdir = $(prefix)/$(perfexecdir)
+perf_include_instdir = $(prefix)/$(libbpf_include_dir)
+perf_examples_instdir = $(prefix)/$(perf_examples_dir)
+STRACE_GROUPS_INSTDIR = $(prefix)/$(STRACE_GROUPS_DIR)
+tip_instdir = $(prefix)/$(tipdir)
+endif
+perfexec_instdir_SQ = $(subst ','\'',$(perfexec_instdir))
+perf_include_instdir_SQ = $(subst ','\'',$(perf_include_instdir))
+perf_examples_instdir_SQ = $(subst ','\'',$(perf_examples_instdir))
+STRACE_GROUPS_INSTDIR_SQ = $(subst ','\'',$(STRACE_GROUPS_INSTDIR))
+tip_instdir_SQ = $(subst ','\'',$(tip_instdir))
+
+export perfexec_instdir_SQ
+
+print_var = $(eval $(print_var_code)) $(info $(MSG))
+define print_var_code
+    MSG = $(shell printf '...%40s: %s' $(1) $($(1)))
+endef
+
+ifeq ($(feature_display),1)
+  $(call feature_display_entries)
+endif
+
+ifeq ($(VF),1)
+  # Display EXTRA features which are detected manualy
+  # from here with feature_check call and thus cannot
+  # be partof global state output.
+  $(foreach feat,$(FEATURE_TESTS_EXTRA),$(call feature_print_status,$(feat),) $(info $(MSG)))
+  $(call print_var,prefix)
+  $(call print_var,bindir)
+  $(call print_var,libdir)
+  $(call print_var,sysconfdir)
+  $(call print_var,LIBUNWIND_DIR)
+  $(call print_var,LIBDW_DIR)
+  $(call print_var,JDIR)
+
+  ifeq ($(dwarf-post-unwind),1)
+    $(call feature_print_text,"DWARF post unwind library", $(dwarf-post-unwind-text)) $(info $(MSG))
+  endif
+endif
+
+$(info )
+
+$(call detected_var,bindir_SQ)
+$(call detected_var,PYTHON_WORD)
+ifneq ($(OUTPUT),)
+$(call detected_var,OUTPUT)
+endif
+$(call detected_var,htmldir_SQ)
+$(call detected_var,infodir_SQ)
+$(call detected_var,mandir_SQ)
+$(call detected_var,ETC_PERFCONFIG_SQ)
+$(call detected_var,STRACE_GROUPS_DIR_SQ)
+$(call detected_var,prefix_SQ)
+$(call detected_var,perfexecdir_SQ)
+$(call detected_var,libbpf_include_dir_SQ)
+$(call detected_var,perf_examples_dir_SQ)
+$(call detected_var,tipdir_SQ)
+$(call detected_var,srcdir_SQ)
+$(call detected_var,LIBDIR)
+$(call detected_var,GTK_CFLAGS)
+$(call detected_var,PERL_EMBED_CCOPTS)
+$(call detected_var,PYTHON_EMBED_CCOPTS)
+ifneq ($(BISON_FILE_PREFIX_MAP),)
+$(call detected_var,BISON_FILE_PREFIX_MAP)
+endif
+
+# re-generate FEATURE-DUMP as we may have called feature_check, found out
+# extra libraries to add to LDFLAGS of some other test and then redo those
+# tests.
+$(shell rm -f $(FEATURE_DUMP_FILENAME))
+$(foreach feat,$(FEATURE_TESTS),$(shell echo "$(call feature_assign,$(feat))" >> $(FEATURE_DUMP_FILENAME)))