selftests/powerpc/ptrace: Explain why tests are skipped

Many tests require specific hardware features/configurations that a
typical machine might not have. As a result, it's common to see a test
is skipped. But it is tedious to find out why a test is skipped
when all it gives is the file location of the skip macro.

Convert SKIP_IF() to SKIP_IF_MSG(), with appropriate descriptions of why
the test is being skipped. This gives a general idea of why a test is
skipped, which can be looked into further if it doesn't make sense.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230725005841.28854-3-bgray@linux.ibm.com

tools/testing/selftests/powerpc/ptrace/child.h

@@ -48,12 +48,12 @@ struct child_sync {
 		}							\
 	} while (0)
 
-#define PARENT_SKIP_IF_UNSUPPORTED(x, sync)				\
+#define PARENT_SKIP_IF_UNSUPPORTED(x, sync, msg)			\
 	do {								\
 		if ((x) == -1 && (errno == ENODEV || errno == EINVAL)) { \
 			(sync)->parent_gave_up = true;			\
 			prod_child(sync);				\
-			SKIP_IF(1);					\
+			SKIP_IF_MSG(1, msg);				\
 		}							\
 	} while (0)
 

tools/testing/selftests/powerpc/ptrace/core-pkey.c

@@ -266,7 +266,7 @@ static int parent(struct shared_info *info, pid_t pid)
 	 * to the child.
 	 */
 	ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
-	PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync);
+	PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync, "PKEYs not supported");
 	PARENT_FAIL_IF(ret, &info->child_sync);
 
 	info->amr = regs[0];

tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c

@@ -884,7 +884,7 @@ static int perf_hwbreak(void)
 {
 	srand ( time(NULL) );
 
-	SKIP_IF(!perf_breakpoint_supported());
+	SKIP_IF_MSG(!perf_breakpoint_supported(), "Perf breakpoints not supported");
 
 	return runtest();
 }

tools/testing/selftests/powerpc/ptrace/ptrace-hwbreak.c

@@ -603,7 +603,7 @@ static int ptrace_hwbreak(void)
 	wait(NULL);
 
 	get_dbginfo(child_pid, &dbginfo);
-	SKIP_IF(dbginfo.num_data_bps == 0);
+	SKIP_IF_MSG(dbginfo.num_data_bps == 0, "No data breakpoints present");
 
 	dawr = dawr_present(&dbginfo);
 	run_tests(child_pid, &dbginfo, dawr);

tools/testing/selftests/powerpc/ptrace/ptrace-perf-hwbreak.c

@@ -641,10 +641,10 @@ static int ptrace_perf_hwbreak(void)
 	wait(NULL); /* <-- child (SIGUSR1) */
 
 	get_dbginfo(child_pid, &dbginfo);
-	SKIP_IF(dbginfo.num_data_bps <= 1);
+	SKIP_IF_MSG(dbginfo.num_data_bps <= 1, "Not enough data watchpoints (need at least 2)");
 
 	ret = perf_cpu_event_open(0, (__u64)perf_data1, sizeof(*perf_data1));
-	SKIP_IF(ret < 0);
+	SKIP_IF_MSG(ret < 0, "perf_event_open syscall failed");
 	close(ret);
 
 	ret = test(child_pid);

tools/testing/selftests/powerpc/ptrace/ptrace-pkey.c

@@ -192,7 +192,7 @@ static int parent(struct shared_info *info, pid_t pid)
 	 * to the child.
 	 */
 	ret = ptrace_read_regs(pid, NT_PPC_PKEY, regs, 3);
-	PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync);
+	PARENT_SKIP_IF_UNSUPPORTED(ret, &info->child_sync, "PKEYs not supported");
 	PARENT_FAIL_IF(ret, &info->child_sync);
 
 	info->amr1 = info->amr2 = regs[0];

tools/testing/selftests/powerpc/ptrace/ptrace-tar.c

@@ -79,7 +79,7 @@ int ptrace_tar(void)
 	int ret, status;
 
 	// TAR was added in v2.07
-	SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07));
+	SKIP_IF_MSG(!have_hwcap2(PPC_FEATURE2_ARCH_2_07), "TAR requires ISA 2.07 compatible hardware");
 
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
 	pid = fork();

tools/testing/selftests/powerpc/ptrace/ptrace-tm-gpr.c

@@ -112,8 +112,8 @@ int ptrace_tm_gpr(void)
 	pid_t pid;
 	int ret, status;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);
 	pid = fork();
 	if (pid < 0) {

tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-gpr.c

@@ -118,8 +118,8 @@ int ptrace_tm_spd_gpr(void)
 	pid_t pid;
 	int ret, status;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
 	pid = fork();
 	if (pid < 0) {

tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-tar.c

@@ -128,8 +128,8 @@ int ptrace_tm_spd_tar(void)
 	pid_t pid;
 	int ret, status;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
 	pid = fork();
 	if (pid == 0)

tools/testing/selftests/powerpc/ptrace/ptrace-tm-spd-vsx.c

@@ -128,8 +128,8 @@ int ptrace_tm_spd_vsx(void)
 	pid_t pid;
 	int ret, status, i;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
 
 	for (i = 0; i < 128; i++) {

tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c

@@ -113,8 +113,8 @@ int ptrace_tm_spr(void)
 	pid_t pid;
 	int ret, status;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(struct shared), 0777|IPC_CREAT);
 	shm_id1 = shmget(IPC_PRIVATE, sizeof(int), 0777|IPC_CREAT);
 	pid = fork();

tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c

@@ -116,8 +116,8 @@ int ptrace_tm_tar(void)
 	pid_t pid;
 	int ret, status;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);
 	pid = fork();
 	if (pid == 0)

tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c

@@ -112,8 +112,8 @@ int ptrace_tm_vsx(void)
 	pid_t pid;
 	int ret, status, i;
 
-	SKIP_IF(!have_htm());
-	SKIP_IF(htm_is_synthetic());
+	SKIP_IF_MSG(!have_htm(), "Don't have transactional memory");
+	SKIP_IF_MSG(htm_is_synthetic(), "Transactional memory is synthetic");
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);
 
 	for (i = 0; i < 128; i++) {

tools/testing/selftests/powerpc/ptrace/ptrace-vsx.c

@@ -61,7 +61,7 @@ int ptrace_vsx(void)
 	pid_t pid;
 	int ret, status, i;
 
-	SKIP_IF(!have_hwcap(PPC_FEATURE_HAS_VSX));
+	SKIP_IF_MSG(!have_hwcap(PPC_FEATURE_HAS_VSX), "Don't have VSX");
 
 	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);