From: Madhavan Srinivasan Date: Mon, 12 Aug 2024 09:41:52 +0000 (+0530) Subject: selftests/powerpc: Allow building without static libc X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=8c9c01ce695eea84d19482e7429e3d54ceb7585c;p=users%2Fwilly%2Fxarray.git selftests/powerpc: Allow building without static libc Currently exec-target.c is linked statically with libc, which on Fedora at least requires installing an additional package (glibc-static). If that package is not installed the build fails with: CC exec_target /usr/bin/ld: cannot find -lc: No such file or directory collect2: error: ld returned 1 exit status All exec_target.c does is call sys_exit, which can be done easily enough using inline assembly, and removes the requirement for a static libc to be installed. Suggested-by: Michael Ellerman Signed-off-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://msgid.link/20240812094152.418586-1-maddy@linux.ibm.com --- diff --git a/tools/testing/selftests/powerpc/benchmarks/Makefile b/tools/testing/selftests/powerpc/benchmarks/Makefile index 1321922038d0..ca4483c238b9 100644 --- a/tools/testing/selftests/powerpc/benchmarks/Makefile +++ b/tools/testing/selftests/powerpc/benchmarks/Makefile @@ -18,4 +18,4 @@ $(OUTPUT)/context_switch: LDLIBS += -lpthread $(OUTPUT)/fork: LDLIBS += -lpthread -$(OUTPUT)/exec_target: CFLAGS += -static -nostartfiles +$(OUTPUT)/exec_target: CFLAGS += -nostartfiles diff --git a/tools/testing/selftests/powerpc/benchmarks/exec_target.c b/tools/testing/selftests/powerpc/benchmarks/exec_target.c index c14b0fc1edde..a6408d3f26cd 100644 --- a/tools/testing/selftests/powerpc/benchmarks/exec_target.c +++ b/tools/testing/selftests/powerpc/benchmarks/exec_target.c @@ -7,10 +7,22 @@ */ #define _GNU_SOURCE -#include #include void _start(void) { - syscall(SYS_exit, 0); + asm volatile ( + "li %%r0, %[sys_exit];" + "li %%r3, 0;" + "sc;" + : + : [sys_exit] "i" (SYS_exit) + /* + * "sc" will clobber r0, r3-r13, cr0, ctr, xer and memory. + * Even though sys_exit never returns, handle clobber + * registers. + */ + : "r0", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", + "r11", "r12", "r13", "cr0", "ctr", "xer", "memory" + ); }