[PATCH] perf arm64: Fix include path for asm-generic/unistd.h

[Kim Phillips <kim.phillips@arm.com>]

The new syscall table support for arm64 mistakenly used the system's
asm-generic/unistd.h file when processing the
tools/arch/arm64/include/uapi/asm/unistd.h file's include directive:

	#include <asm-generic/unistd.h>

See "Committer notes" section of commit 2b5882435606 "perf arm64:
Generate system call table from asm/unistd.h" for more details.

This patch removes the committer's temporary workaround, and instructs
the host compiler to search the build tree's include path for the right
copy of the unistd.h file, instead of the one on the system's
/usr/include path.

It thus fixes the committer's test that cross-builds an arm64 perf
on an x86 platform running Ubuntu 14.04.5 LTS with an old toolchain:

$ tools/perf/arch/arm64/entry/syscalls/mksyscalltbl /gcc-linaro-5.4.1-2017.05-x86_64_aarch64-linux-gnu/bin/aarch64-linux-gnu-gcc gcc `pwd`/tools tools/arch/arm64/include/uapi/asm/unistd.h | grep bpf
	[280] = "bpf",

Cc: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Fixes: 2b5882435606 ("perf arm64: Generate system call table from asm/unistd.h")
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
---
Hi, sorry for late response - was on vacation.  I was able to reproduce
and fix by adding this -I to the $hostcc line.  Please test, and let me
know if this is an acceptable fix.

 tools/perf/arch/arm64/Makefile                    | 5 +++--
 tools/perf/arch/arm64/entry/syscalls/mksyscalltbl | 6 +++---
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/tools/perf/arch/arm64/Makefile b/tools/perf/arch/arm64/Makefile
index f013b115dc86..dbef716a1913 100644
--- a/tools/perf/arch/arm64/Makefile
+++ b/tools/perf/arch/arm64/Makefile
@@ -11,7 +11,8 @@ PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
 
 out    := $(OUTPUT)arch/arm64/include/generated/asm
 header := $(out)/syscalls.c
-sysdef := $(srctree)/tools/include/uapi/asm-generic/unistd.h
+incpath := $(srctree)/tools
+sysdef := $(srctree)/tools/arch/arm64/include/uapi/asm/unistd.h
 sysprf := $(srctree)/tools/perf/arch/arm64/entry/syscalls/
 systbl := $(sysprf)/mksyscalltbl
 
@@ -19,7 +20,7 @@ systbl := $(sysprf)/mksyscalltbl
 _dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)')
 
 $(header): $(sysdef) $(systbl)
-	$(Q)$(SHELL) '$(systbl)' '$(CC)' '$(HOSTCC)' $(sysdef) > $@
+	$(Q)$(SHELL) '$(systbl)' '$(CC)' '$(HOSTCC)' $(incpath) $(sysdef) > $@
 
 clean::
 	$(call QUIET_CLEAN, arm64) $(RM) $(header)
diff --git a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
index 52e197317d3e..2dbb8cade048 100755
--- a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
+++ b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
@@ -11,7 +11,8 @@
 
 gcc=$1
 hostcc=$2
-input=$3
+incpath=$3
+input=$4
 
 if ! test -r $input; then
 	echo "Could not read input file" >&2
@@ -28,7 +29,6 @@ create_table_from_c()
 
 	cat <<-_EoHEADER
 		#include <stdio.h>
-		#define __ARCH_WANT_RENAMEAT
 		#include "$input"
 		int main(int argc, char *argv[])
 		{
@@ -42,7 +42,7 @@ create_table_from_c()
 	printf "%s\n" "	printf(\"#define SYSCALLTBL_ARM64_MAX_ID %d\\n\", __NR_$last_sc);"
 	printf "}\n"
 
-	} | $hostcc -o $create_table_exe -x c -
+	} | $hostcc -I $incpath/include/uapi -o $create_table_exe -x c -
 
 	$create_table_exe
 
-- 
2.17.1