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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [XEN PATCH for-4.13 v3 3/7] libxl: Rename ev_devlock to ev_slowlock
We are going to introduce a different lock based on the same
implementation as the ev_devlock but with a different path. The
different slowlock will be differentiated by calling different _init()
functions.
So we rename libxl__ev_devlock to lib__ev_slowlock, but keep
libxl__ev_devlock_init().
Some log messages produced ev_slowlock are changed to print the
name of the lock file (userdata_userid).
Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
Acked-by: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
---
Notes:
New patch in v2.
Instead of introducing many libxl__ev_qmplock*.
tools/libxl/libxl_disk.c | 10 +++++-----
tools/libxl/libxl_domain.c | 10 +++++-----
tools/libxl/libxl_internal.c | 30 +++++++++++++++++++-----------
tools/libxl/libxl_internal.h | 33 +++++++++++++++++----------------
4 files changed, 46 insertions(+), 37 deletions(-)
diff --git a/tools/libxl/libxl_disk.c b/tools/libxl/libxl_disk.c
index 733ad284c866..77ae3a59bfb6 100644
--- a/tools/libxl/libxl_disk.c
+++ b/tools/libxl/libxl_disk.c
@@ -648,13 +648,13 @@ typedef struct {
libxl_domid domid;
libxl_device_disk *disk;
libxl_device_disk disk_saved;
- libxl__ev_devlock qmp_lock;
+ libxl__ev_slowlock qmp_lock;
int dm_ver;
libxl__ev_time time;
libxl__ev_qmp qmp;
} libxl__cdrom_insert_state;
-static void cdrom_insert_lock_acquired(libxl__egc *, libxl__ev_devlock *,
+static void cdrom_insert_lock_acquired(libxl__egc *, libxl__ev_slowlock *,
int rc);
static void cdrom_insert_ejected(libxl__egc *egc, libxl__ev_qmp *,
const libxl__json_object *, int rc);
@@ -746,13 +746,13 @@ int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid,
libxl_device_disk *disk,
cdrom_insert_done(egc, cis, rc); /* must be last */
} else {
cis->qmp_lock.callback = cdrom_insert_lock_acquired;
- libxl__ev_devlock_lock(egc, &cis->qmp_lock); /* must be last */
+ libxl__ev_slowlock_lock(egc, &cis->qmp_lock); /* must be last */
}
return AO_INPROGRESS;
}
static void cdrom_insert_lock_acquired(libxl__egc *egc,
- libxl__ev_devlock *lock,
+ libxl__ev_slowlock *lock,
int rc)
{
libxl__cdrom_insert_state *cis = CONTAINER_OF(lock, *cis, qmp_lock);
@@ -1052,7 +1052,7 @@ static void cdrom_insert_done(libxl__egc *egc,
libxl__ev_time_deregister(gc, &cis->time);
libxl__ev_qmp_dispose(gc, &cis->qmp);
if (cis->qmp.payload_fd >= 0) close(cis->qmp.payload_fd);
- libxl__ev_devlock_unlock(gc, &cis->qmp_lock);
+ libxl__ev_slowlock_unlock(gc, &cis->qmp_lock);
libxl_device_disk_dispose(&cis->disk_saved);
libxl__ao_complete(egc, cis->ao, rc);
}
diff --git a/tools/libxl/libxl_domain.c b/tools/libxl/libxl_domain.c
index 33f9d9eaa481..7ca7a224f9a4 100644
--- a/tools/libxl/libxl_domain.c
+++ b/tools/libxl/libxl_domain.c
@@ -1874,12 +1874,12 @@ typedef struct {
libxl__ev_qmp qmp;
libxl__ev_time timeout;
libxl_domain_config *d_config; /* user pointer */
- libxl__ev_devlock devlock;
+ libxl__ev_slowlock devlock;
libxl_bitmap qemuu_cpus;
} retrieve_domain_configuration_state;
static void retrieve_domain_configuration_lock_acquired(
- libxl__egc *egc, libxl__ev_devlock *, int rc);
+ libxl__egc *egc, libxl__ev_slowlock *, int rc);
static void retrieve_domain_configuration_cpu_queried(
libxl__egc *egc, libxl__ev_qmp *qmp,
const libxl__json_object *response, int rc);
@@ -1907,12 +1907,12 @@ int libxl_retrieve_domain_configuration(libxl_ctx *ctx,
uint32_t domid,
rdcs->devlock.ao = ao;
rdcs->devlock.domid = domid;
rdcs->devlock.callback = retrieve_domain_configuration_lock_acquired;
- libxl__ev_devlock_lock(egc, &rdcs->devlock);
+ libxl__ev_slowlock_lock(egc, &rdcs->devlock);
return AO_INPROGRESS;
}
static void retrieve_domain_configuration_lock_acquired(
- libxl__egc *egc, libxl__ev_devlock *devlock, int rc)
+ libxl__egc *egc, libxl__ev_slowlock *devlock, int rc)
{
retrieve_domain_configuration_state *rdcs =
CONTAINER_OF(devlock, *rdcs, devlock);
@@ -2204,7 +2204,7 @@ static void retrieve_domain_configuration_end(libxl__egc
*egc,
}
out:
- libxl__ev_devlock_unlock(gc, &rdcs->devlock);
+ libxl__ev_slowlock_unlock(gc, &rdcs->devlock);
if (lock) libxl__unlock_domain_userdata(lock);
libxl_bitmap_dispose(&rdcs->qemuu_cpus);
libxl__ev_qmp_dispose(gc, &rdcs->qmp);
diff --git a/tools/libxl/libxl_internal.c b/tools/libxl/libxl_internal.c
index 0750b69cba61..9520ac36149e 100644
--- a/tools/libxl/libxl_internal.c
+++ b/tools/libxl/libxl_internal.c
@@ -575,25 +575,32 @@ void libxl__update_domain_configuration(libxl__gc *gc,
dst->b_info.video_memkb = src->b_info.video_memkb;
}
-void libxl__ev_devlock_init(libxl__ev_devlock *lock)
+static void ev_slowlock_init_internal(libxl__ev_slowlock *lock,
+ const char *userdata_userid)
{
libxl__ev_child_init(&lock->child);
+ lock->userdata_userid = userdata_userid;
lock->path = NULL;
lock->fd = -1;
lock->held = false;
}
-static void ev_lock_prepare_fork(libxl__egc *egc, libxl__ev_devlock *lock);
+void libxl__ev_devlock_init(libxl__ev_slowlock *lock)
+{
+ ev_slowlock_init_internal(lock, "libxl-device-changes-lock");
+}
+
+static void ev_lock_prepare_fork(libxl__egc *egc, libxl__ev_slowlock *lock);
static void ev_lock_child_callback(libxl__egc *egc, libxl__ev_child *child,
pid_t pid, int status);
-void libxl__ev_devlock_lock(libxl__egc *egc, libxl__ev_devlock *lock)
+void libxl__ev_slowlock_lock(libxl__egc *egc, libxl__ev_slowlock *lock)
{
STATE_AO_GC(lock->ao);
const char *lockfile;
lockfile = libxl__userdata_path(gc, lock->domid,
- "libxl-device-changes-lock", "l");
+ lock->userdata_userid, "l");
if (!lockfile) goto out;
lock->path = libxl__strdup(NOGC, lockfile);
@@ -603,7 +610,7 @@ void libxl__ev_devlock_lock(libxl__egc *egc,
libxl__ev_devlock *lock)
lock->callback(egc, lock, ERROR_LOCK_FAIL);
}
-static void ev_lock_prepare_fork(libxl__egc *egc, libxl__ev_devlock *lock)
+static void ev_lock_prepare_fork(libxl__egc *egc, libxl__ev_slowlock *lock)
{
STATE_AO_GC(lock->ao);
pid_t pid;
@@ -670,7 +677,7 @@ static void ev_lock_prepare_fork(libxl__egc *egc,
libxl__ev_devlock *lock)
libxl_fd_set_cloexec(CTX, fd, 1);
return;
out:
- libxl__ev_devlock_unlock(gc, lock);
+ libxl__ev_slowlock_unlock(gc, lock);
lock->callback(egc, lock, ERROR_LOCK_FAIL);
}
@@ -678,7 +685,7 @@ static void ev_lock_child_callback(libxl__egc *egc,
libxl__ev_child *child,
pid_t pid, int status)
{
EGC_GC;
- libxl__ev_devlock *lock = CONTAINER_OF(child, *lock, child);
+ libxl__ev_slowlock *lock = CONTAINER_OF(child, *lock, child);
struct stat stab, fstab;
int rc = ERROR_LOCK_FAIL;
@@ -726,13 +733,14 @@ static void ev_lock_child_callback(libxl__egc *egc,
libxl__ev_child *child,
rc = ERROR_LOCK_FAIL;
}
if (rc) {
- LOGD(ERROR, domid, "Failed to grab qmp-lock");
- libxl__ev_devlock_unlock(gc, lock);
+ LOGD(ERROR, domid, "Failed to grab lock for %s",
+ lock->userdata_userid);
+ libxl__ev_slowlock_unlock(gc, lock);
}
lock->callback(egc, lock, rc);
}
-void libxl__ev_devlock_unlock(libxl__gc *gc, libxl__ev_devlock *lock)
+void libxl__ev_slowlock_unlock(libxl__gc *gc, libxl__ev_slowlock *lock)
{
int r;
@@ -754,7 +762,7 @@ void libxl__ev_devlock_unlock(libxl__gc *gc,
libxl__ev_devlock *lock)
close(lock->fd);
}
free(lock->path);
- libxl__ev_devlock_init(lock);
+ ev_slowlock_init_internal(lock, lock->userdata_userid);
}
/*
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 69d572c1866a..a0f99252c39c 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -196,7 +196,7 @@ typedef struct libxl__osevent_hook_nexi
libxl__osevent_hook_nexi;
typedef struct libxl__device_type libxl__device_type;
typedef struct libxl__json_object libxl__json_object;
typedef struct libxl__carefd libxl__carefd;
-typedef struct libxl__ev_devlock libxl__ev_devlock;
+typedef struct libxl__ev_slowlock libxl__ev_slowlock;
typedef struct libxl__dm_resume_state libxl__dm_resume_state;
typedef struct libxl__ao_device libxl__ao_device;
typedef struct libxl__multidev libxl__multidev;
@@ -366,7 +366,7 @@ struct libxl__ev_child {
/*
* Lock for device hotplug, qmp_lock.
*
- * libxl__ev_devlock implement a lock that is outside of CTX_LOCK in the
+ * libxl__ev_slowlock implement a lock that is outside of CTX_LOCK in the
* lock hierarchy. It can be used when one want to make QMP calls to QEMU,
* which may take a significant amount time.
* It is to be acquired by an ao event callback.
@@ -374,42 +374,43 @@ struct libxl__ev_child {
* It is to be acquired when adding/removing devices or making changes
* to them when this is a slow operation and json_lock isn't appropriate.
*
- * Possible states of libxl__ev_devlock:
+ * Possible states of libxl__ev_slowlock:
* Undefined
* Might contain anything.
* Idle
* Struct contents are defined enough to pass to any
- * libxl__ev_devlock_* function.
+ * libxl__ev_slowlock_* function.
* The struct does not contain references to any allocated private
* resources so can be thrown away.
* Active
* Waiting to get a lock.
* Needs to wait until the callback is called.
* LockAcquired
- * libxl__ev_devlock_unlock will need to be called to release the lock
- * and the resources of libxl__ev_devlock.
+ * libxl__ev_slowlock_unlock will need to be called to release the lock
+ * and the resources of libxl__ev_slowlock.
*
- * libxl__ev_devlock_init: Undefined/Idle -> Idle
- * libxl__ev_devlock_lock: Idle -> Active
+ * libxl__ev_*lock_init: Undefined/Idle -> Idle
+ * libxl__ev_slowlock_lock: Idle -> Active
* May call callback synchronously.
- * libxl__ev_devlock_unlock: LockAcquired/Idle -> Idle
+ * libxl__ev_slowlock_unlock: LockAcquired/Idle -> Idle
* callback: When called: Active -> LockAcquired (on error: Idle)
* The callback is only called once.
*/
-struct libxl__ev_devlock {
+struct libxl__ev_slowlock {
/* filled by user */
libxl__ao *ao;
libxl_domid domid;
- void (*callback)(libxl__egc *, libxl__ev_devlock *, int rc);
- /* private to libxl__ev_devlock* */
+ void (*callback)(libxl__egc *, libxl__ev_slowlock *, int rc);
+ /* private to libxl__ev_slowlock* */
libxl__ev_child child;
+ const char *userdata_userid;
char *path; /* path of the lock file itself */
int fd;
bool held;
};
-_hidden void libxl__ev_devlock_init(libxl__ev_devlock *);
-_hidden void libxl__ev_devlock_lock(libxl__egc *, libxl__ev_devlock *);
-_hidden void libxl__ev_devlock_unlock(libxl__gc *, libxl__ev_devlock *);
+_hidden void libxl__ev_devlock_init(libxl__ev_slowlock *);
+_hidden void libxl__ev_slowlock_lock(libxl__egc *, libxl__ev_slowlock *);
+_hidden void libxl__ev_slowlock_unlock(libxl__gc *, libxl__ev_slowlock *);
/*
* QMP asynchronous calls
@@ -2853,7 +2854,7 @@ struct libxl__multidev {
* unlock json config
*
* Or in case QEMU is the primary config, this pattern can be use:
- * qmp_lock (libxl__ev_devlock)
+ * qmp_lock (libxl__ev_devlock_init)
* lock json config (json_lock)
* read json config
* update in-memory json config with new entry, replacing
--
Anthony PERARD
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