mirror of
https://git.proxmox.com/git/qemu
synced 2025-10-31 11:55:48 +00:00
625a5befc2
When using ballooning to manage overcommitted memory on a host, a system for guests to communicate their memory usage to the host can provide information that will minimize the impact of ballooning on the guests. The current method employs a daemon running in each guest that communicates memory statistics to a host daemon at a specified time interval. The host daemon aggregates this information and inflates and/or deflates balloons according to the level of host memory pressure. This approach is effective but overly complex since a daemon must be installed inside each guest and coordinated to communicate with the host. A simpler approach is to collect memory statistics in the virtio balloon driver and communicate them directly to the hypervisor. Signed-off-by: Adam Litke <agl@us.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
56 lines
1.5 KiB
C
56 lines
1.5 KiB
C
/*
|
|
* Virtio Support
|
|
*
|
|
* Copyright IBM, Corp. 2007-2008
|
|
*
|
|
* Authors:
|
|
* Anthony Liguori <aliguori@us.ibm.com>
|
|
* Rusty Russell <rusty@rustcorp.com.au>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2. See
|
|
* the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#ifndef _QEMU_VIRTIO_BALLOON_H
|
|
#define _QEMU_VIRTIO_BALLOON_H
|
|
|
|
#include "virtio.h"
|
|
#include "pci.h"
|
|
|
|
/* from Linux's linux/virtio_balloon.h */
|
|
|
|
/* The ID for virtio_balloon */
|
|
#define VIRTIO_ID_BALLOON 5
|
|
|
|
/* The feature bitmap for virtio balloon */
|
|
#define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */
|
|
#define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory stats virtqueue */
|
|
|
|
/* Size of a PFN in the balloon interface. */
|
|
#define VIRTIO_BALLOON_PFN_SHIFT 12
|
|
|
|
struct virtio_balloon_config
|
|
{
|
|
/* Number of pages host wants Guest to give up. */
|
|
uint32_t num_pages;
|
|
/* Number of pages we've actually got in balloon. */
|
|
uint32_t actual;
|
|
};
|
|
|
|
/* Memory Statistics */
|
|
#define VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */
|
|
#define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */
|
|
#define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */
|
|
#define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */
|
|
#define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */
|
|
#define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */
|
|
#define VIRTIO_BALLOON_S_NR 6
|
|
|
|
typedef struct VirtIOBalloonStat {
|
|
uint16_t tag;
|
|
uint64_t val;
|
|
} __attribute__((packed)) VirtIOBalloonStat;
|
|
|
|
#endif
|