diff options
Diffstat (limited to 'drivers/block/xen-blkback/xenbus.c')
| -rw-r--r-- | drivers/block/xen-blkback/xenbus.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 4c5d99f87813..42944d41aea0 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -467,7 +467,6 @@ static void xenvbd_sysfs_delif(struct xenbus_device *dev) device_remove_file(&dev->dev, &dev_attr_physical_device); } - static void xen_vbd_free(struct xen_vbd *vbd) { if (vbd->bdev) @@ -524,6 +523,7 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle, handle, blkif->domid); return 0; } + static int xen_blkbk_remove(struct xenbus_device *dev) { struct backend_info *be = dev_get_drvdata(&dev->dev); @@ -607,6 +607,7 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info if (err) dev_warn(&dev->dev, "writing feature-discard (%d)", err); } + int xen_blkbk_barrier(struct xenbus_transaction xbt, struct backend_info *be, int state) { @@ -691,7 +692,6 @@ fail: return err; } - /* * Callback received when the hotplug scripts have placed the physical-device * node. Read it and the mode node, and create a vbd. If the frontend is @@ -783,7 +783,6 @@ static void backend_changed(struct xenbus_watch *watch, } } - /* * Callback received when the frontend's state changes. */ @@ -858,9 +857,27 @@ static void frontend_changed(struct xenbus_device *dev, } } +/* Once a memory pressure is detected, squeeze free page pools for a while. */ +static unsigned int buffer_squeeze_duration_ms = 10; +module_param_named(buffer_squeeze_duration_ms, + buffer_squeeze_duration_ms, int, 0644); +MODULE_PARM_DESC(buffer_squeeze_duration_ms, +"Duration in ms to squeeze pages buffer when a memory pressure is detected"); -/* ** Connection ** */ +/* + * Callback received when the memory pressure is detected. + */ +static void reclaim_memory(struct xenbus_device *dev) +{ + struct backend_info *be = dev_get_drvdata(&dev->dev); + if (!be) + return; + be->blkif->buffer_squeeze_end = jiffies + + msecs_to_jiffies(buffer_squeeze_duration_ms); +} + +/* ** Connection ** */ /* * Write the physical details regarding the block device to the store, and @@ -1152,6 +1169,7 @@ static struct xenbus_driver xen_blkbk_driver = { .remove = xen_blkbk_remove, .otherend_changed = frontend_changed, .allow_rebind = true, + .reclaim_memory = reclaim_memory, }; int xen_blkif_xenbus_init(void) |