perf build: Install libperf locally when building

The perf build currently has a '-Itools/lib' on the CC command
line. This causes issues as the libapi, libsubcmd, libtraceevent,
libbpf headers are all found via this path, making it impossible to
override include behavior.

Change the libperf build mirroring the libbpf, libsubcmd and libapi
build, so that it is installed in a directory along with its headers. A
later change will modify the include behavior.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20221109184914.1357295-6-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/.gitignore

@@ -41,6 +41,7 @@ pmu-events/jevents
 feature/
 libapi/
 libbpf/
+libperf/
 libsubcmd/
 fixdep
 libtraceevent-dynamic-list

tools/perf/Makefile.perf

@@ -294,11 +294,9 @@ strip-libs = $(filter-out -l%,$(1))
 ifneq ($(OUTPUT),)
   TE_PATH=$(OUTPUT)
   PLUGINS_PATH=$(OUTPUT)
-  LIBPERF_PATH=$(OUTPUT)
 else
   TE_PATH=$(TRACE_EVENT_DIR)
   PLUGINS_PATH=$(TRACE_EVENT_DIR)plugins/
-  LIBPERF_PATH=$(LIBPERF_DIR)
 endif
 
 LIBTRACEEVENT = $(TE_PATH)libtraceevent.a
@@ -340,7 +338,14 @@ LIBSUBCMD_DESTDIR = $(LIBSUBCMD_OUTPUT)
 LIBSUBCMD_INCLUDE = $(LIBSUBCMD_DESTDIR)/include
 LIBSUBCMD = $(LIBSUBCMD_OUTPUT)/libsubcmd.a
 
-LIBPERF = $(LIBPERF_PATH)libperf.a
+ifneq ($(OUTPUT),)
+  LIBPERF_OUTPUT = $(abspath $(OUTPUT))/libperf
+else
+  LIBPERF_OUTPUT = $(CURDIR)/libperf
+endif
+LIBPERF_DESTDIR = $(LIBPERF_OUTPUT)
+LIBPERF_INCLUDE = $(LIBPERF_DESTDIR)/include
+LIBPERF = $(LIBPERF_OUTPUT)/libperf.a
 export LIBPERF
 
 # python extension build directories
@@ -850,12 +855,14 @@ $(LIBBPF)-clean:
 	$(call QUIET_CLEAN, libbpf)
 	$(Q)$(RM) -r -- $(LIBBPF_OUTPUT)
 
-$(LIBPERF): FORCE
-	$(Q)$(MAKE) -C $(LIBPERF_DIR) EXTRA_CFLAGS="$(LIBPERF_CFLAGS)" O=$(OUTPUT) $(OUTPUT)libperf.a
+$(LIBPERF): FORCE | $(LIBPERF_OUTPUT)
+	$(Q)$(MAKE) -C $(LIBPERF_DIR) O=$(LIBPERF_OUTPUT) \
+		DESTDIR=$(LIBPERF_DESTDIR) prefix= \
+		$@ install_headers
 
 $(LIBPERF)-clean:
 	$(call QUIET_CLEAN, libperf)
-	$(Q)$(MAKE) -C $(LIBPERF_DIR) O=$(OUTPUT) clean >/dev/null
+	$(Q)$(RM) -r -- $(LIBPERF_OUTPUT)
 
 $(LIBSUBCMD): FORCE | $(LIBSUBCMD_OUTPUT)
 	$(Q)$(MAKE) -C $(LIBSUBCMD_DIR) O=$(LIBSUBCMD_OUTPUT) \
@@ -1050,7 +1057,7 @@ SKELETONS += $(SKEL_OUT)/bperf_cgroup.skel.h $(SKEL_OUT)/func_latency.skel.h
 SKELETONS += $(SKEL_OUT)/off_cpu.skel.h $(SKEL_OUT)/lock_contention.skel.h
 SKELETONS += $(SKEL_OUT)/kwork_trace.skel.h
 
-$(SKEL_TMP_OUT) $(LIBAPI_OUTPUT) $(LIBBPF_OUTPUT) $(LIBSUBCMD_OUTPUT):
+$(SKEL_TMP_OUT) $(LIBAPI_OUTPUT) $(LIBBPF_OUTPUT) $(LIBPERF_OUTPUT) $(LIBSUBCMD_OUTPUT):
 	$(Q)$(MKDIR) -p $@
 
 ifdef BUILD_BPF_SKEL