|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH 04/11] mini-os/xenbus: Change type of xenbus_event_queue
We change xenbus_event_queue from a pointer typedef to a struct, for
two reasons:
1. In a moment we are going to want to extend this struct to include
a minios scheduler wait queue.
2. We can replace the open-coded list with a MINIOS_STAILQ.
All the xenbus users need to call the new initialisation function
instead of simply initialising the struct to NULL, and have their
parameter type changed.
There is a functional side-effect: now we are using a tail queue,
rather than a tailless queue, we insert events at the end rather than
the beginning. So watch events now come out in chronological order,
rather than their order possibly being scrambled in the queue.
Signed-off-by: Ian Jackson <Ian.Jackson@xxxxxxxxxxxxx>
---
include/mini-os/console.h | 2 +-
include/mini-os/xenbus.h | 22 +++++++++++++---------
xen/blkfront.c | 4 ++--
xen/console/xenbus.c | 2 +-
xen/netfront.c | 4 ++--
xen/pcifront.c | 7 ++++---
xen/xenbus/xenbus.c | 31 +++++++++++++++++++------------
7 files changed, 42 insertions(+), 30 deletions(-)
diff --git a/include/mini-os/console.h b/include/mini-os/console.h
index 1b04b13..49990b9 100644
--- a/include/mini-os/console.h
+++ b/include/mini-os/console.h
@@ -56,7 +56,7 @@ struct consfront_dev {
char *nodename;
char *backend;
- xenbus_event_queue events;
+ struct xenbus_event_queue events;
};
diff --git a/include/mini-os/xenbus.h b/include/mini-os/xenbus.h
index f3594cb..4dad4c8 100644
--- a/include/mini-os/xenbus.h
+++ b/include/mini-os/xenbus.h
@@ -2,6 +2,7 @@
#define MINIOS_XENBUS_H__
#include <xen/io/xenbus.h>
+#include <mini-os/queue.h>
typedef unsigned long xenbus_transaction_t;
#define XBT_NIL ((xenbus_transaction_t)0)
@@ -25,22 +26,25 @@ struct xenbus_event {
/* Keep these two as this for xs.c */
char *path;
char *token;
- struct xenbus_event *next;
+ MINIOS_STAILQ_ENTRY(xenbus_event) entry;
};
-typedef struct xenbus_event *xenbus_event_queue;
+struct xenbus_event_queue {
+ MINIOS_STAILQ_HEAD(, xenbus_event) events;
+};
+
+void xenbus_event_queue_init(struct xenbus_event_queue *queue);
-char *xenbus_watch_path_token(xenbus_transaction_t xbt, const char *path,
const char *token, xenbus_event_queue *events);
+char *xenbus_watch_path_token(xenbus_transaction_t xbt, const char *path,
const char *token, struct xenbus_event_queue *events);
char *xenbus_unwatch_path_token(xenbus_transaction_t xbt, const char *path,
const char *token);
-extern struct wait_queue_head xenbus_watch_queue;
-void xenbus_wait_for_watch(xenbus_event_queue *queue);
-char **xenbus_wait_for_watch_return(xenbus_event_queue *queue);
-char* xenbus_wait_for_value(const char *path, const char *value,
xenbus_event_queue *queue);
-char *xenbus_wait_for_state_change(const char* path, XenbusState *state,
xenbus_event_queue *queue);
+void xenbus_wait_for_watch(struct xenbus_event_queue *queue);
+char **xenbus_wait_for_watch_return(struct xenbus_event_queue *queue);
+char* xenbus_wait_for_value(const char *path, const char *value, struct
xenbus_event_queue *queue);
+char *xenbus_wait_for_state_change(const char* path, XenbusState *state,
struct xenbus_event_queue *queue);
char *xenbus_switch_state(xenbus_transaction_t xbt, const char* path,
XenbusState state);
/* When no token is provided, use a global queue. */
#define XENBUS_WATCH_PATH_TOKEN "xenbus_watch_path"
-extern xenbus_event_queue xenbus_events;
+extern struct xenbus_event_queue xenbus_events;
#define xenbus_watch_path(xbt, path) xenbus_watch_path_token(xbt, path,
XENBUS_WATCH_PATH_TOKEN, NULL)
#define xenbus_unwatch_path(xbt, path) xenbus_unwatch_path_token(xbt, path,
XENBUS_WATCH_PATH_TOKEN)
diff --git a/xen/blkfront.c b/xen/blkfront.c
index 347c68c..a5da53d 100644
--- a/xen/blkfront.c
+++ b/xen/blkfront.c
@@ -47,7 +47,7 @@ struct blkfront_dev {
char *backend;
struct blkfront_info info;
- xenbus_event_queue events;
+ struct xenbus_event_queue events;
};
@@ -103,7 +103,7 @@ struct blkfront_dev *init_blkfront(char *_nodename, struct
blkfront_info *info)
dev->ring_ref = gnttab_grant_access(dev->dom,virt_to_mfn(s),0);
- dev->events = NULL;
+ xenbus_event_queue_init(&dev->events);
again:
err = xenbus_transaction_start(&xbt);
diff --git a/xen/console/xenbus.c b/xen/console/xenbus.c
index d848af8..a164314 100644
--- a/xen/console/xenbus.c
+++ b/xen/console/xenbus.c
@@ -96,7 +96,7 @@ struct consfront_dev *init_consfront(char *_nodename)
memset(dev->ring, 0, PAGE_SIZE);
dev->ring_ref = gnttab_grant_access(dev->dom, virt_to_mfn(dev->ring), 0);
- dev->events = NULL;
+ xenbus_event_queue_init(&dev->events);
again:
err = xenbus_transaction_start(&xbt);
diff --git a/xen/netfront.c b/xen/netfront.c
index 9e17a86..a89a0dd 100644
--- a/xen/netfront.c
+++ b/xen/netfront.c
@@ -51,7 +51,7 @@ struct netfront_dev {
char *backend;
char *mac;
- xenbus_event_queue events;
+ struct xenbus_event_queue events;
void (*netif_rx)(struct netfront_dev *, unsigned char* data, int len);
@@ -313,7 +313,7 @@ struct netfront_dev *init_netfront(char *_nodename, void
(*thenetif_rx)(struct n
dev->netif_rx = thenetif_rx;
- dev->events = NULL;
+ xenbus_event_queue_init(&dev->events);
again:
err = xenbus_transaction_start(&xbt);
diff --git a/xen/pcifront.c b/xen/pcifront.c
index 6f52b77..7bd3788 100644
--- a/xen/pcifront.c
+++ b/xen/pcifront.c
@@ -31,7 +31,7 @@ struct pcifront_dev {
char *nodename;
char *backend;
- xenbus_event_queue events;
+ struct xenbus_event_queue events;
};
void pcifront_handler(evtchn_port_t port, struct pt_regs *regs, void *data)
@@ -64,7 +64,8 @@ void pcifront_watches(void *opaque)
char* nodename = opaque ? opaque : "device/pci/0";
char path[strlen(nodename) + 9];
char fe_state[strlen(nodename) + 7];
- xenbus_event_queue events = NULL;
+ struct xenbus_event_queue events;
+ xenbus_event_queue_init(&events);
snprintf(path, sizeof(path), "%s/backend", nodename);
snprintf(fe_state, sizeof(fe_state), "%s/state", nodename);
@@ -174,7 +175,7 @@ struct pcifront_dev *init_pcifront(char *_nodename)
dev->info_ref = gnttab_grant_access(dev->dom,virt_to_mfn(dev->info),0);
- dev->events = NULL;
+ xenbus_event_queue_init(&dev->events);
again:
err = xenbus_transaction_start(&xbt);
diff --git a/xen/xenbus/xenbus.c b/xen/xenbus/xenbus.c
index a06dc30..8a14c3b 100644
--- a/xen/xenbus/xenbus.c
+++ b/xen/xenbus/xenbus.c
@@ -48,10 +48,10 @@ static DECLARE_WAIT_QUEUE_HEAD(xb_waitq);
static spinlock_t xb_lock = SPIN_LOCK_UNLOCKED; /* protects xenbus req ring */
DECLARE_WAIT_QUEUE_HEAD(xenbus_watch_queue);
-xenbus_event_queue xenbus_events;
+struct xenbus_event_queue xenbus_events;
static struct watch {
char *token;
- xenbus_event_queue *events;
+ struct xenbus_event_queue *events;
struct watch *next;
} *watches;
struct xenbus_req_info
@@ -61,6 +61,13 @@ struct xenbus_req_info
void *reply;
};
+
+void xenbus_event_queue_init(struct xenbus_event_queue *queue)
+{
+ MINIOS_STAILQ_INIT(&queue->events);
+}
+
+
#define NR_REQS 32
static struct xenbus_req_info req_info[NR_REQS];
@@ -78,22 +85,22 @@ static void memcpy_from_ring(const void *Ring,
memcpy(dest + c1, ring, c2);
}
-char **xenbus_wait_for_watch_return(xenbus_event_queue *queue)
+char **xenbus_wait_for_watch_return(struct xenbus_event_queue *queue)
{
struct xenbus_event *event;
DEFINE_WAIT(w);
if (!queue)
queue = &xenbus_events;
- while (!(event = *queue)) {
+ while (!(event = MINIOS_STAILQ_FIRST(&queue->events))) {
add_waiter(w, xenbus_watch_queue);
schedule();
}
remove_waiter(w, xenbus_watch_queue);
- *queue = event->next;
+ MINIOS_STAILQ_REMOVE_HEAD(&queue->events, entry);
return &event->path;
}
-void xenbus_wait_for_watch(xenbus_event_queue *queue)
+void xenbus_wait_for_watch(struct xenbus_event_queue *queue)
{
char **ret;
if (!queue)
@@ -105,7 +112,7 @@ void xenbus_wait_for_watch(xenbus_event_queue *queue)
printk("unexpected path returned by watch\n");
}
-char* xenbus_wait_for_value(const char* path, const char* value,
xenbus_event_queue *queue)
+char* xenbus_wait_for_value(const char* path, const char* value, struct
xenbus_event_queue *queue)
{
if (!queue)
queue = &xenbus_events;
@@ -168,7 +175,7 @@ exit:
return msg;
}
-char *xenbus_wait_for_state_change(const char* path, XenbusState *state,
xenbus_event_queue *queue)
+char *xenbus_wait_for_state_change(const char* path, XenbusState *state,
struct xenbus_event_queue *queue)
{
if (!queue)
queue = &xenbus_events;
@@ -227,7 +234,7 @@ static void xenbus_thread_func(void *ign)
if(msg.type == XS_WATCH_EVENT)
{
struct xenbus_event *event = malloc(sizeof(*event) + msg.len);
- xenbus_event_queue *events = NULL;
+ struct xenbus_event_queue *events = NULL;
char *data = (char*)event + sizeof(*event);
struct watch *watch;
@@ -248,8 +255,7 @@ static void xenbus_thread_func(void *ign)
}
if (events) {
- event->next = *events;
- *events = event;
+ MINIOS_STAILQ_INSERT_TAIL(&events->events, event, entry);
wake_up(&xenbus_watch_queue);
} else {
printk("unexpected watch token %s\n", event->token);
@@ -332,6 +338,7 @@ void init_xenbus(void)
{
int err;
DEBUG("init_xenbus called.\n");
+ xenbus_event_queue_init(&xenbus_events);
xenstore_buf = mfn_to_virt(start_info.store_mfn);
create_thread("xenstore", xenbus_thread_func, NULL);
DEBUG("buf at %p.\n", xenstore_buf);
@@ -561,7 +568,7 @@ char *xenbus_write(xenbus_transaction_t xbt, const char
*path, const char *value
return NULL;
}
-char* xenbus_watch_path_token( xenbus_transaction_t xbt, const char *path,
const char *token, xenbus_event_queue *events)
+char* xenbus_watch_path_token( xenbus_transaction_t xbt, const char *path,
const char *token, struct xenbus_event_queue *events)
{
struct xsd_sockmsg *rep;
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |