[LTP] [PATCH] Shell wrappers for the checkpoint interface

[LTP] [PATCH] Shell wrappers for the checkpoint interface

[Stanislav Kholmanskikh]

This patch provides necessary wrappers to use the checkpoint
API in shell tests.

Big thanks to Cyril and Jan for their comments to the RFC versions.

Signed-off-by: Stanislav Kholmanskikh <stanislav.kholmanskikh@oracle.com>
---
Changes since RFC:
 * Single tst_checkpoint binary instead of tst_checkpoint_{wait,wake}
 * Changed the order of arguments passed to the binary
 * The 'wake' command of the binary requires NR_WAKE paramater.
 * Implement wrappers to all TST_CHECKPOINT_ functions
 * Use TCID in LTP_IPC_PATH
 * Add docs. Noted that the shell functions are compatible to C
   counterparts (initialized with tst_reinit).

 doc/test-writing-guidelines.txt |   23 ++++++++-
 testcases/lib/.gitignore        |    1 +
 testcases/lib/Makefile          |    6 +-
 testcases/lib/test.sh           |   38 +++++++++++++++
 testcases/lib/tst_checkpoint.c  |  101 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 165 insertions(+), 4 deletions(-)
 create mode 100644 testcases/lib/tst_checkpoint.c

diff --git a/doc/test-writing-guidelines.txt b/doc/test-writing-guidelines.txt
index cdff39c..b58a526 100644
--- a/doc/test-writing-guidelines.txt
+++ b/doc/test-writing-guidelines.txt
@@ -583,7 +583,7 @@ As LTP tests are written for Linux, most of the tests involve fork()-ing and
 parent-child process synchronization. LTP includes a checkpoint library that
 provides wait/wake futex based functions.
 
-In order to use checkpoints the '.need_chekcpoints' flag in the 'struct
+In order to use checkpoints the '.needs_checkpoints' flag in the 'struct
 tst_test' must be set to '1', this causes the test library to initialize
 checkpoints before the 'test()' function is called.
 
@@ -1400,6 +1400,27 @@ else
 fi
 -------------------------------------------------------------------------------
 
+2.3.6 Access to the checkpoint interface
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The shell library provides an implementation of the checkpoint interface
+compatible with the C version. All TST_CHECKPOINT_* functions are available.
+
+In order to initialize checkpoints '$TST_NEEDS_CHECKPOINTS' must be set to '1'
+before the inclusion of 'test.sh':
+
+[source,sh]
+-------------------------------------------------------------------------------
+#!/bin/sh
+
+TST_NEEDS_CHECKPOINTS=1
+. test.sh
+-------------------------------------------------------------------------------
+
+Since both the implementations are compatible, it's also possible to start
+a child binary process from a shell test and synchronize with it. This process
+must have checkpoints initialized by calling tst_reinit()'.
+
 3. Common problems
 ------------------
 
diff --git a/testcases/lib/.gitignore b/testcases/lib/.gitignore
index 8886b34..3227552 100644
--- a/testcases/lib/.gitignore
+++ b/testcases/lib/.gitignore
@@ -1 +1,2 @@
 tst_sleep
+tst_checkpoint
diff --git a/testcases/lib/Makefile b/testcases/lib/Makefile
index 0bfb149..c625c6e 100644
--- a/testcases/lib/Makefile
+++ b/testcases/lib/Makefile
@@ -22,10 +22,10 @@
 
 top_srcdir		?= ../..
 
-include $(top_srcdir)/include/mk/env_pre.mk
+include $(top_srcdir)/include/mk/testcases.mk
 
-INSTALL_TARGETS		:= *.sh tst_sleep
+INSTALL_TARGETS		:= *.sh
 
-MAKE_TARGETS		:= tst_sleep
+MAKE_TARGETS		:= tst_sleep tst_checkpoint
 
 include $(top_srcdir)/include/mk/generic_leaf_target.mk
diff --git a/testcases/lib/test.sh b/testcases/lib/test.sh
index e118a56..9f1e3be 100644
--- a/testcases/lib/test.sh
+++ b/testcases/lib/test.sh
@@ -100,6 +100,10 @@ tst_exit()
 		$TST_CLEANUP
 	fi
 
+	if [ -n "$LTP_IPC_PATH" -a -f "$LTP_IPC_PATH" ]; then
+		rm -f "$LTP_IPC_PATH"
+	fi
+
 	# Mask out TINFO
 	exit $((LTP_RET_VAL & ~16))
 }
@@ -383,6 +387,27 @@ tst_su()
 	su "$usr" -c "PATH=\$PATH:$LTPROOT/testcases/bin/ $@"
 }
 
+TST_CHECKPOINT_WAIT()
+{
+	ROD tst_checkpoint wait 10000 "$1"
+}
+
+TST_CHECKPOINT_WAKE()
+{
+	ROD tst_checkpoint wake 10000 "$1" 1
+}
+
+TST_CHECKPOINT_WAKE2()
+{
+	ROD tst_checkpoint wake 10000 "$1" "$2"
+}
+
+TST_CHECKPOINT_WAKE_AND_WAIT()
+{
+	TST_CHECKPOINT_WAKE
+	TST_CHECKPOINT_WAIT
+}
+
 # Check that test name is set
 if [ -z "$TCID" ]; then
 	tst_brkm TBROK "TCID is not defined"
@@ -402,3 +427,16 @@ if [ -z "$LTPROOT" ]; then
 else
 	export LTP_DATAROOT="$LTPROOT/testcases/data/$TCID"
 fi
+
+if [ "$TST_NEEDS_CHECKPOINTS" = "1" ]; then
+	LTP_IPC_PATH="/dev/shm/ltp_${TCID}_$$"
+
+	LTP_IPC_SIZE=$(getconf PAGESIZE)
+	if [ $? -ne 0 ]; then
+		tst_brkm TBROK "getconf PAGESIZE failed"
+	fi
+
+	ROD_SILENT dd if=/dev/zero of="$LTP_IPC_PATH" bs="$LTP_IPC_SIZE" count=1
+	ROD_SILENT chmod 600 "$LTP_IPC_PATH"
+	export LTP_IPC_PATH
+fi
diff --git a/testcases/lib/tst_checkpoint.c b/testcases/lib/tst_checkpoint.c
new file mode 100644
index 0000000..712657e
--- /dev/null
+++ b/testcases/lib/tst_checkpoint.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2016 Linux Test Project
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#define TST_NO_DEFAULT_MAIN
+#include "tst_test.h"
+
+static void print_help(void)
+{
+	printf("Usage: tst_checkpoint wait TIMEOUT ID\n");
+	printf("   or: tst_checkpoint wake TIMEOUT ID NR_WAKE\n");
+	printf("       TIMEOUT - timeout in ms\n");
+	printf("       ID - checkpoint id\n");
+	printf("       NR_WAKE - number of processes to wake up\n");
+}
+
+static int get_val(const char *name, const char *arg, unsigned int *val)
+{
+	unsigned long temp;
+	char *e;
+
+	errno = 0;
+	temp = strtoul(arg, &e, 10);
+	if (errno || (e == arg) || (temp > UINT_MAX)) {
+		fprintf(stderr, "ERROR: Invalid %s '%s'\n",
+			name, arg);
+		return -1;
+	}
+
+	*val = temp;
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int id, timeout, nr_wake;
+	int ret;
+	int type;
+
+	if (argc < 3)
+		goto help;
+
+	if (!strcmp(argv[1], "wait")) {
+		type = 0;
+
+		if (argc != 4)
+			goto help;
+	} else if (!strcmp(argv[1], "wake")) {
+		type = 1;
+
+		if (argc != 5)
+			goto help;
+
+		if (get_val("NR_WAKE", argv[4], &nr_wake))
+			goto help;
+	} else {
+		fprintf(stderr, "ERROR: Invalid COMMAND '%s'\n",
+			argv[1]);
+		goto help;
+	}
+
+	if (get_val("TIMEOUT", argv[2], &timeout)
+	    || get_val("ID", argv[3], &id)) {
+		goto help;
+	}
+
+	tst_reinit();
+
+	if (!type)
+		ret = tst_checkpoint_wait(id, timeout);
+	else
+		ret = tst_checkpoint_wake(id, nr_wake, timeout);
+
+	if (ret)
+		return 1;
+	else
+		return 0;
+
+help:
+	print_help();
+	return 1;
+}
-- 
1.7.1

[LTP] [PATCH] Shell wrappers for the checkpoint interface

[Cyril Hrubis]

Hi!
> +	if (!type)
> +		ret = tst_checkpoint_wait(id, timeout);
> +	else
> +		ret = tst_checkpoint_wake(id, nr_wake, timeout);

I find it silly that you do negate the flag here. You could have set it
the other way, or swap the wait and wake in the if and else branch...

Anyway the rest looks good to me, ackend.

-- 
Cyril Hrubis
chrubis@suse.cz

[LTP] [PATCH] Shell wrappers for the checkpoint interface

[Stanislav Kholmanskikh]

Hi!

On 06/08/2016 05:23 PM, Cyril Hrubis wrote:
> Hi!
>> +	if (!type)
>> +		ret = tst_checkpoint_wait(id, timeout);
>> +	else
>> +		ret = tst_checkpoint_wake(id, nr_wake, timeout);
>
> I find it silly that you do negate the flag here. You could have set it
> the other way, or swap the wait and wake in the if and else branch...

I swapped the wait and wake and pushed it.

Thanks!


>
> Anyway the rest looks good to me, ackend.
>