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Diffstat (limited to 'drivers/hv/hv_balloon.c')
-rw-r--r--drivers/hv/hv_balloon.c63
1 files changed, 54 insertions, 9 deletions
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index dd289fd179c..37873213e24 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -29,7 +29,6 @@
#include <linux/memory_hotplug.h>
#include <linux/memory.h>
#include <linux/notifier.h>
-#include <linux/mman.h>
#include <linux/percpu_counter.h>
#include <linux/hyperv.h>
@@ -415,10 +414,17 @@ struct dm_info_msg {
static bool hot_add;
static bool do_hot_add;
+/*
+ * Delay reporting memory pressure by
+ * the specified number of seconds.
+ */
+static uint pressure_report_delay = 30;
module_param(hot_add, bool, (S_IRUGO | S_IWUSR));
MODULE_PARM_DESC(hot_add, "If set attempt memory hot_add");
+module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR));
+MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure");
static atomic_t trans_id = ATOMIC_INIT(0);
static int dm_ring_size = (5 * PAGE_SIZE);
@@ -517,6 +523,34 @@ static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
}
}
+unsigned long compute_balloon_floor(void)
+{
+ unsigned long min_pages;
+#define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT))
+ /* Simple continuous piecewiese linear function:
+ * max MiB -> min MiB gradient
+ * 0 0
+ * 16 16
+ * 32 24
+ * 128 72 (1/2)
+ * 512 168 (1/4)
+ * 2048 360 (1/8)
+ * 8192 552 (1/32)
+ * 32768 1320
+ * 131072 4392
+ */
+ if (totalram_pages < MB2PAGES(128))
+ min_pages = MB2PAGES(8) + (totalram_pages >> 1);
+ else if (totalram_pages < MB2PAGES(512))
+ min_pages = MB2PAGES(40) + (totalram_pages >> 2);
+ else if (totalram_pages < MB2PAGES(2048))
+ min_pages = MB2PAGES(104) + (totalram_pages >> 3);
+ else
+ min_pages = MB2PAGES(296) + (totalram_pages >> 5);
+#undef MB2PAGES
+ return min_pages;
+}
+
/*
* Post our status as it relates memory pressure to the
* host. Host expects the guests to post this status
@@ -530,15 +564,30 @@ static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg)
static void post_status(struct hv_dynmem_device *dm)
{
struct dm_status status;
+ struct sysinfo val;
-
+ if (pressure_report_delay > 0) {
+ --pressure_report_delay;
+ return;
+ }
+ si_meminfo(&val);
memset(&status, 0, sizeof(struct dm_status));
status.hdr.type = DM_STATUS_REPORT;
status.hdr.size = sizeof(struct dm_status);
status.hdr.trans_id = atomic_inc_return(&trans_id);
-
- status.num_committed = vm_memory_committed();
+ /*
+ * The host expects the guest to report free memory.
+ * Further, the host expects the pressure information to
+ * include the ballooned out pages.
+ * For a given amount of memory that we are managing, we
+ * need to compute a floor below which we should not balloon.
+ * Compute this and add it to the pressure report.
+ */
+ status.num_avail = val.freeram;
+ status.num_committed = vm_memory_committed() +
+ dm->num_pages_ballooned +
+ compute_balloon_floor();
vmbus_sendpacket(dm->dev->channel, &status,
sizeof(struct dm_status),
@@ -547,8 +596,6 @@ static void post_status(struct hv_dynmem_device *dm)
}
-
-
static void free_balloon_pages(struct hv_dynmem_device *dm,
union dm_mem_page_range *range_array)
{
@@ -1013,9 +1060,7 @@ static int balloon_remove(struct hv_device *dev)
static const struct hv_vmbus_device_id id_table[] = {
/* Dynamic Memory Class ID */
/* 525074DC-8985-46e2-8057-A307DC18A502 */
- { VMBUS_DEVICE(0xdc, 0x74, 0x50, 0X52, 0x85, 0x89, 0xe2, 0x46,
- 0x80, 0x57, 0xa3, 0x07, 0xdc, 0x18, 0xa5, 0x02)
- },
+ { HV_DM_GUID, },
{ },
};