2 commits - init.d/sanlock python/sanlock.c src/delta_lease.c src/sanlock_internal.h

[David Teigland]

 init.d/sanlock         |    2 ++
 python/sanlock.c       |   30 +++++++++++++++++++++---------
 src/delta_lease.c      |    6 ++++++
 src/sanlock_internal.h |    4 ++++
 4 files changed, 33 insertions(+), 9 deletions(-)

New commits:
commit 9e299a36cca6d07205ecd43b18ebca773396f727
Author: Federico Simoncelli <fsimonce(a)redhat.com&gt;
Date:   Mon Dec 19 16:32:43 2011 +0000

    python: acquire leases for other processes
    
    The python binding was lacking the support for acquiring leases on
    behalf of other processes.
    
    Signed-off-by: Federico Simoncelli <fsimonce(a)redhat.com&gt;

diff --git a/python/sanlock.c b/python/sanlock.c
index 9c1bfa0..79b7e2d 100644
--- a/python/sanlock.c
+++ b/python/sanlock.c
@@ -343,21 +343,26 @@ py_rem_lockspace(PyObject *self __unused, PyObject *args)
 
 /* acquire */
 PyDoc_STRVAR(pydoc_acquire, "\
-acquire(fd, lockspace, resource, disks)\n\
-Acquire a resource lease for the current process.\n\
-The disks must be in the format: [(path, offset), ... ]");
+acquire(lockspace, resource, disks [, slkfd=fd, pid=owner])\n\
+Acquire a resource lease for the current process (using the slkfd argument\n\
+to specify the sanlock file descriptor) or for an other process (using the\n\
+pid argument).\n\
+The disks must be in the format: [(path, offset), ... ]\n");
 
 static PyObject *
-py_acquire(PyObject *self __unused, PyObject *args)
+py_acquire(PyObject *self __unused, PyObject *args, PyObject *keywds)
 {
-    int rv, sanlockfd;
+    int rv, sanlockfd = -1, pid = -1;
     const char *lockspace, *resource;
     struct sanlk_resource *res;
     PyObject *disks;
 
+    static char *kwlist[] = {"lockspace", "resource",
"disks", "slkfd",
+                                "pid", NULL};
+
     /* parse python tuple */
-    if (!PyArg_ParseTuple(args, "issO!",
-        &sanlockfd, &lockspace, &resource, &PyList_Type, &disks)) {
+    if (!PyArg_ParseTupleAndKeywords(args, keywds, "ssO!|ii", kwlist,
+        &lockspace, &resource, &PyList_Type, &disks, &sanlockfd,
&pid)) {
         return NULL;
     }
 
@@ -366,13 +371,19 @@ py_acquire(PyObject *self __unused, PyObject *args)
         return NULL;
     }
 
+    /* check if any of the slkfd or pid parameters was given */
+    if (sanlockfd == -1 && pid == -1) {
+        __set_exception(EINVAL, "Invalid slkfd and pid values");
+        return NULL;
+    }
+
     /* prepare sanlock names */
     strncpy(res->lockspace_name, lockspace, SANLK_NAME_LEN);
     strncpy(res->name, resource, SANLK_NAME_LEN);
 
     /* acquire sanlock resource (gil disabled) */
     Py_BEGIN_ALLOW_THREADS
-    rv = sanlock_acquire(sanlockfd, -1, 0, 1, &res, 0);
+    rv = sanlock_acquire(sanlockfd, pid, 0, 1, &res, 0);
     Py_END_ALLOW_THREADS
 
     if (rv != 0) {
@@ -462,7 +473,8 @@ sanlock_methods[] = {
                         METH_VARARGS|METH_KEYWORDS, pydoc_init_resource},
     {"add_lockspace", py_add_lockspace, METH_VARARGS, pydoc_add_lockspace},
     {"rem_lockspace", py_rem_lockspace, METH_VARARGS, pydoc_rem_lockspace},
-    {"acquire", py_acquire, METH_VARARGS, pydoc_acquire},
+    {"acquire", (PyCFunction) py_acquire,
+                METH_VARARGS|METH_KEYWORDS, pydoc_acquire},
     {"release", py_release, METH_VARARGS, pydoc_release},
     {NULL, NULL, 0, NULL}
 };


commit 4cdb754d208ac108fa3a65cb463ad8eed42a0f46
Author: David Teigland <teigland(a)redhat.com&gt;
Date:   Mon Dec 19 12:07:10 2011 -0600

    sanlock: quick host_id reacquire
    
    when we were the last owner.
    
    Also use sanlock uid/gid in init script.
    
    Signed-off-by: David Teigland <teigland(a)redhat.com&gt;

diff --git a/init.d/sanlock b/init.d/sanlock
index 74df2c9..b2682ef 100644
--- a/init.d/sanlock
+++ b/init.d/sanlock
@@ -25,6 +25,8 @@ prog="sanlock"
 lockfile="/var/run/$prog/$prog.pid"
 exec="/usr/sbin/$prog"
 
+SANLOCKOPTS="-U sanlock -G sanlock"
+
 [ -f /etc/sysconfig/$prog ] && . /etc/sysconfig/$prog
 
 start() {
diff --git a/src/delta_lease.c b/src/delta_lease.c
index 53cbd5e..64bc123 100644
--- a/src/delta_lease.c
+++ b/src/delta_lease.c
@@ -211,6 +211,12 @@ int delta_lease_acquire(struct task *task,
 	if (leader.timestamp == LEASE_FREE)
 		goto write_new;
 
+	if (!strncmp(leader.resource_name, our_host_name, NAME_ID_SIZE)) {
+		log_space(sp, "delta_acquire %llu fast reacquire",
+			  (unsigned long long)host_id);
+		goto write_new;
+	}
+
 	/* we need to ensure that a host_id cannot be acquired and released
 	 * sooner than host_dead_seconds because the change in host_id
 	 * ownership affects the host_id "liveness" determination used by paxos
diff --git a/src/sanlock_internal.h b/src/sanlock_internal.h
index 46e2b36..567b704 100644
--- a/src/sanlock_internal.h
+++ b/src/sanlock_internal.h
@@ -429,6 +429,10 @@ struct space {
  * 3. ios can't be reliably canceled and never really time out; an io is only
  * really dead when the machine is dead/reset or storage access is cut off.
  * The delta lease algorithm expects real io timeouts.
+ *
+ * So, the delay is really meant to represent the time until we are certain a
+ * host is safely gone and will no longer write, and for sanlock that means
+ * until the watchdog has reset it.
  */
 
 #define HOSTID_AIO_CB_SIZE 4