From 9854e7ad35fecf3007d44e58484e05cf39a62bd6 Mon Sep 17 00:00:00 2001 From: Hans-Peter Nilsson Date: Mon, 28 Dec 2020 03:41:59 +0100 Subject: [PATCH] perf arm64: Simplify mksyscalltbl This patch isn't intended to have any effect on the compiled code. It just removes one level of indirection: calling the *host* compiler to build and then run a program that just printf:s the numerical entries of the syscall-table. In other words, the generated syscalls.c changes from: [46] = "ftruncate", to: [__NR3264_ftruncate] = "ftruncate", The latter is as good as the former to the user of perf, and this can be done directly by the shell-script. The syscalls defined as non-literal values (like "#define __NR_ftruncate __NR3264_ftruncate") are trivially resolved at compile-time without namespace-leaking and/or collision for its sole user, perf/util/syscalltbl.c, that just #includes the generated file. A future "-mabi=32" support would probably have to handle this differently, but that is a pre-existing problem not affected by this simplification. Calling the *host* compiler only complicates things and accidentally can get a completely wrong set of files and syscall numbers, see earlier commits. Note that the script parameter hostcc is now unused. At the time of this patch, powerpc (the origin, see comments), and also e.g. x86 has moved on, from filtering "gcc -dM -E" output to reading separate specific text-file, a table of syscall numbers. IMHO should arm64 consider adopting this. Signed-off-by: Hans-Peter Nilsson Cc: Alexander Shishkin Reviewed-by: Leo Yan Tested-by: Leo Yan Acked-by: Arnd Bergmann Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Kim Phillips Cc: Leo Yan Cc: Mark Rutland Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20201228024159.2BB66203B5@pchp3.se.axis.com Signed-off-by: Arnaldo Carvalho de Melo --- .../arch/arm64/entry/syscalls/mksyscalltbl | 23 +++---------------- 1 file changed, 3 insertions(+), 20 deletions(-) diff --git a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl index a7ca48d1e37b..22cdf911dd9a 100755 --- a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl +++ b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl @@ -23,34 +23,17 @@ create_table_from_c() { local sc nr last_sc - create_table_exe=`mktemp ${TMPDIR:-/tmp}/create-table-XXXXXX` - - { - - cat <<-_EoHEADER - #include - #include "$input" - int main(int argc, char *argv[]) - { - _EoHEADER - while read sc nr; do - printf "%s\n" " printf(\"\\t[%d] = \\\"$sc\\\",\\n\", __NR_$sc);" + printf "%s\n" " [$nr] = \"$sc\"," last_sc=$sc done - printf "%s\n" " printf(\"#define SYSCALLTBL_ARM64_MAX_ID %d\\n\", __NR_$last_sc);" - printf "}\n" - - } | $hostcc -I $incpath/include/uapi -o $create_table_exe -x c - - - $create_table_exe - - rm -f $create_table_exe + printf "%s\n" "#define SYSCALLTBL_ARM64_MAX_ID __NR_$last_sc" } create_table() { + echo "#include \"$input\"" echo "static const char *syscalltbl_arm64[] = {" create_table_from_c echo "};"