[PATCH v12 23/30] selftests/powerpc: Add ptrace tests for TAR, PPR, DSCR in TM

[wei . guo . simon]

From: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>

This patch adds ptrace interface test for TAR, PPR, DSCR
registers inside TM context. This also adds ptrace
interface based helper functions related to checkpointed
TAR, PPR, DSCR register access.

Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Cc: Anton Blanchard <anton@xxxxxxxxx>
Cc: Cyril Bur <cyrilbur@xxxxxxxxx>
Cc: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>
Cc: Simon Guo <wei.guo.simon@xxxxxxxxx>
Cc: Ulrich Weigand <ulrich.weigand@xxxxxxxxxx>
Cc: Michael Neuling <mikey@xxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Rashmica Gupta <rashmicy@xxxxxxxxx>
Cc: Khem Raj <raj.khem@xxxxxxxxx>
Cc: Jessica Yu <jeyu@xxxxxxxxxx>
Cc: Jiri Kosina <jkosina@xxxxxxx>
Cc: Miroslav Benes <mbenes@xxxxxxx>
Cc: Suraj Jitindar Singh <sjitindarsingh@xxxxxxxxx>
Cc: Chris Smart <chris@xxxxxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Simon Guo <wei.guo.simon@xxxxxxxxx>
---
 tools/testing/selftests/powerpc/ptrace/Makefile    |   2 +-
 .../selftests/powerpc/ptrace/ptrace-tm-tar.c       | 182 +++++++++++++++++++++
 2 files changed, 183 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c

diff --git a/tools/testing/selftests/powerpc/ptrace/Makefile b/tools/testing/selftests/powerpc/ptrace/Makefile
index c794057..77d7a13 100644
--- a/tools/testing/selftests/powerpc/ptrace/Makefile
+++ b/tools/testing/selftests/powerpc/ptrace/Makefile
@@ -1,5 +1,5 @@
 TEST_PROGS := ptrace-ebb ptrace-gpr ptrace-tm-gpr ptrace-tm-spd-gpr \
-ptrace-tar
+ptrace-tar ptrace-tm-tar
 
 all: $(TEST_PROGS)
 CFLAGS += -m64
diff --git a/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c
new file mode 100644
index 0000000..1fd006c
--- /dev/null
+++ b/tools/testing/selftests/powerpc/ptrace/ptrace-tm-tar.c
@@ -0,0 +1,182 @@
+/*
+ * Ptrace test for TAR, PPR, DSCR registers in the TM context
+ *
+ * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include "ptrace.h"
+#include "ptrace-tar.h"
+
+int shm_id;
+volatile unsigned long *cptr, *pptr;
+
+
+void tm_tar(void)
+{
+	unsigned long result, texasr;
+	unsigned long regs[3];
+	int ret;
+
+	cptr = (unsigned long *)shmat(shm_id, NULL, 0);
+
+trans:
+	cptr[1] = 0;
+	asm __volatile__(
+		"li	4, %[tar_1];"
+		"mtspr %[sprn_tar],  4;"	/* TAR_1 */
+		"li	4, %[dscr_1];"
+		"mtspr %[sprn_dscr], 4;"	/* DSCR_1 */
+		"or     31,31,31;"		/* PPR_1*/
+
+		"1: ;"
+		TBEGIN
+		"beq 2f;"
+
+		"li	4, %[tar_2];"
+		"mtspr %[sprn_tar],  4;"	/* TAR_2 */
+		"li	4, %[dscr_2];"
+		"mtspr %[sprn_dscr], 4;"	/* DSCR_2 */
+		"or     1,1,1;"			/* PPR_2 */
+		TSUSPEND
+		"li 0, 1;"
+		"stw 0, 0(%[cptr1]);"
+		TRESUME
+		"b .;"
+
+		TEND
+		"li 0, 0;"
+		"ori %[res], 0, 0;"
+		"b 3f;"
+
+		/* Transaction abort handler */
+		"2: ;"
+		"li 0, 1;"
+		"ori %[res], 0, 0;"
+		"mfspr %[texasr], %[sprn_texasr];"
+
+		"3: ;"
+
+		: [res] "=r" (result), [texasr] "=r" (texasr)
+		: [sprn_dscr]"i"(SPRN_DSCR), [sprn_tar]"i"(SPRN_TAR),
+		[sprn_ppr]"i"(SPRN_PPR), [sprn_texasr]"i"(SPRN_TEXASR),
+		[tar_1]"i"(TAR_1), [dscr_1]"i"(DSCR_1), [tar_2]"i"(TAR_2),
+		[dscr_2]"i"(DSCR_2), [cptr1] "r" (&cptr[1])
+		: "memory", "r0", "r1", "r3", "r4", "r5", "r6"
+		);
+
+	/* TM failed, analyse */
+	if (result) {
+		if (!cptr[0])
+			goto trans;
+
+		regs[0] = mfspr(SPRN_TAR);
+		regs[1] = mfspr(SPRN_PPR);
+		regs[2] = mfspr(SPRN_DSCR);
+
+		shmdt(&cptr);
+		printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
+				user_read, regs[0], regs[1], regs[2]);
+
+		ret = validate_tar_registers(regs, TAR_4, PPR_4, DSCR_4);
+		if (ret)
+			exit(1);
+		exit(0);
+	}
+	shmdt(&cptr);
+	exit(1);
+}
+
+int trace_tm_tar(pid_t child)
+{
+	unsigned long regs[3];
+	int ret;
+
+	ret = start_trace(child);
+	if (ret)
+		return TEST_FAIL;
+
+	ret = show_tar_registers(child, regs);
+	if (ret)
+		return TEST_FAIL;
+
+	printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
+			ptrace_read_running, regs[0], regs[1], regs[2]);
+
+	ret = validate_tar_registers(regs, TAR_2, PPR_2, DSCR_2);
+	if (ret)
+		return TEST_FAIL;
+
+	ret = show_tm_checkpointed_state(child, regs);
+	if (ret)
+		return TEST_FAIL;
+
+	printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
+			ptrace_read_ckpt, regs[0], regs[1], regs[2]);
+
+	ret = validate_tar_registers(regs, TAR_1, PPR_1, DSCR_1);
+	if (ret)
+		return TEST_FAIL;
+
+	ret = write_ckpt_tar_registers(child, TAR_4, PPR_4, DSCR_4);
+	if (ret)
+		return TEST_FAIL;
+
+	printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
+			ptrace_write_ckpt, TAR_4, PPR_4, DSCR_4);
+
+	pptr[0] = 1;
+	ret = stop_trace(child);
+	if (ret)
+		return TEST_FAIL;
+	return TEST_PASS;
+}
+
+int ptrace_tm_tar(void)
+{
+	pid_t pid;
+	int ret, status;
+
+	SKIP_IF(!((long)get_auxv_entry(AT_HWCAP2) & PPC_FEATURE2_HTM));
+	shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);
+	pid = fork();
+	if (pid == 0)
+		tm_tar();
+
+	pptr = (unsigned long *)shmat(shm_id, NULL, 0);
+	pptr[0] = 0;
+
+	if (pid) {
+		while (!pptr[1]);
+		ret = trace_tm_tar(pid);
+		if (ret) {
+			kill(pid, SIGTERM);
+			shmdt(&pptr);
+			shmctl(shm_id, IPC_RMID, NULL);
+			return TEST_FAIL;
+		}
+		shmdt(&pptr);
+
+		ret = wait(&status);
+		shmctl(shm_id, IPC_RMID, NULL);
+		if (ret != pid) {
+			printf("Child's exit status not captured\n");
+			return TEST_FAIL;
+		}
+
+		if (WIFEXITED(status)) {
+			if (WEXITSTATUS(status))
+				return TEST_FAIL;
+		}
+		return TEST_PASS;
+	}
+	return TEST_PASS;
+}
+
+int main(int argc, char *argv[])
+{
+	return test_harness(ptrace_tm_tar, "ptrace_tm_tar");
+}
-- 
1.8.3.1