selftests/x86: remove (or use) unused variables and functions

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...quite a few functions are variables are generating "unused" warnings.
Fix the warnings by deleting the unused items.

One item, the "nerrs" variable in vsdo_restorer.c's main(), is unused
but probably wants to be returned from main(), as a non-zero result.
That result is also unused right now, so another option would be to
delete it entirely, but this way, main() also gets fixed. It was missing
a return value.
Acked-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/x86/amx.c

@@ -39,16 +39,6 @@ struct xsave_buffer {
 	};
 };
 
-static inline uint64_t xgetbv(uint32_t index)
-{
-	uint32_t eax, edx;
-
-	asm volatile("xgetbv;"
-		     : "=a" (eax), "=d" (edx)
-		     : "c" (index));
-	return eax + ((uint64_t)edx << 32);
-}
-
 static inline void xsave(struct xsave_buffer *xbuf, uint64_t rfbm)
 {
 	uint32_t rfbm_lo = rfbm;
@@ -164,12 +154,6 @@ static inline void clear_xstate_header(struct xsave_buffer *buffer)
 	memset(&buffer->header, 0, sizeof(buffer->header));
 }
 
-static inline uint64_t get_xstatebv(struct xsave_buffer *buffer)
-{
-	/* XSTATE_BV is at the beginning of the header: */
-	return *(uint64_t *)&buffer->header;
-}
-
 static inline void set_xstatebv(struct xsave_buffer *buffer, uint64_t bv)
 {
 	/* XSTATE_BV is at the beginning of the header: */

tools/testing/selftests/x86/fsgsbase.c

@@ -109,11 +109,6 @@ static inline void wrgsbase(unsigned long gsbase)
 	asm volatile("wrgsbase %0" :: "r" (gsbase) : "memory");
 }
 
-static inline void wrfsbase(unsigned long fsbase)
-{
-	asm volatile("wrfsbase %0" :: "r" (fsbase) : "memory");
-}
-
 enum which_base { FS, GS };
 
 static unsigned long read_base(enum which_base which)
@@ -212,7 +207,6 @@ static void mov_0_gs(unsigned long initial_base, bool schedule)
 }
 
 static volatile unsigned long remote_base;
-static volatile bool remote_hard_zero;
 static volatile unsigned int ftx;
 
 /*

tools/testing/selftests/x86/syscall_arg_fault.c

@@ -29,7 +29,6 @@ static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),
 		err(1, "sigaction");
 }
 
-static volatile sig_atomic_t sig_traps;
 static sigjmp_buf jmpbuf;
 
 static volatile sig_atomic_t n_errs;

tools/testing/selftests/x86/test_vsyscall.c

@@ -97,11 +97,6 @@ static inline long sys_gtod(struct timeval *tv, struct timezone *tz)
 	return syscall(SYS_gettimeofday, tv, tz);
 }
 
-static inline int sys_clock_gettime(clockid_t id, struct timespec *ts)
-{
-	return syscall(SYS_clock_gettime, id, ts);
-}
-
 static inline long sys_time(time_t *t)
 {
 	return syscall(SYS_time, t);

tools/testing/selftests/x86/vdso_restorer.c

@@ -92,4 +92,6 @@ int main()
 		printf("[FAIL]\t!SA_SIGINFO handler was not called\n");
 		nerrs++;
 	}
+
+	return nerrs;
 }