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VMware balloon: add batching to the vmw_balloon.
Introduce a new capability to the driver that allow sending 512 pages in one hypervisor call. This reduce the cost of the driver when reclaiming memory. Signed-off-by: Xavier Deguillard <xdeguillard@vmware.com> Acked-by: Dmitry Torokhov <dtor@vmware.com> Signed-off-by: Philip P. Moltmann <moltmann@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Xavier Deguillard
Greg Kroah-Hartman
parent
4d4896a507
commit
f220a80f0c
@ -1,7 +1,7 @@
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/*
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* VMware Balloon driver.
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*
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* Copyright (C) 2000-2010, VMware, Inc. All Rights Reserved.
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* Copyright (C) 2000-2013, VMware, Inc. All Rights Reserved.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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@ -37,6 +37,7 @@
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/vmalloc.h>
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#include <linux/sched.h>
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#include <linux/module.h>
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#include <linux/workqueue.h>
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@ -46,7 +47,7 @@
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MODULE_AUTHOR("VMware, Inc.");
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MODULE_DESCRIPTION("VMware Memory Control (Balloon) Driver");
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MODULE_VERSION("1.3.0.0-k");
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MODULE_VERSION("1.3.1.0-k");
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MODULE_ALIAS("dmi:*:svnVMware*:*");
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MODULE_ALIAS("vmware_vmmemctl");
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MODULE_LICENSE("GPL");
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@ -120,13 +121,26 @@ enum vmwballoon_capabilities {
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VMW_BALLOON_BATCHED_CMDS = (1 << 2)
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};
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#define VMW_BALLOON_CAPABILITIES (VMW_BALLOON_BASIC_CMDS)
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#define VMW_BALLOON_CAPABILITIES (VMW_BALLOON_BASIC_CMDS \
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| VMW_BALLOON_BATCHED_CMDS)
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/*
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* Backdoor commands availability:
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*
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* START, GET_TARGET and GUEST_ID are always available,
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*
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* VMW_BALLOON_BASIC_CMDS:
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* LOCK and UNLOCK commands,
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* VMW_BALLOON_BATCHED_CMDS:
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* BATCHED_LOCK and BATCHED_UNLOCK commands.
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*/
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#define VMW_BALLOON_CMD_START 0
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#define VMW_BALLOON_CMD_GET_TARGET 1
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#define VMW_BALLOON_CMD_LOCK 2
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#define VMW_BALLOON_CMD_UNLOCK 3
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#define VMW_BALLOON_CMD_GUEST_ID 4
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#define VMW_BALLOON_CMD_BATCHED_LOCK 6
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#define VMW_BALLOON_CMD_BATCHED_UNLOCK 7
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/* error codes */
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#define VMW_BALLOON_SUCCESS 0
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@ -142,18 +156,63 @@ enum vmwballoon_capabilities {
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#define VMW_BALLOON_SUCCESS_WITH_CAPABILITIES (0x03000000)
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#define VMWARE_BALLOON_CMD(cmd, data, result) \
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/* Batch page description */
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/*
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* Layout of a page in the batch page:
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*
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* +-------------+----------+--------+
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* | | | |
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* | Page number | Reserved | Status |
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* | | | |
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* +-------------+----------+--------+
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* 64 PAGE_SHIFT 6 0
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*
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* For now only 4K pages are supported, but we can easily support large pages
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* by using bits in the reserved field.
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*
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* The reserved field should be set to 0.
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*/
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#define VMW_BALLOON_BATCH_MAX_PAGES (PAGE_SIZE / sizeof(u64))
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#define VMW_BALLOON_BATCH_STATUS_MASK ((1UL << 5) - 1)
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#define VMW_BALLOON_BATCH_PAGE_MASK (~((1UL << PAGE_SHIFT) - 1))
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struct vmballoon_batch_page {
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u64 pages[VMW_BALLOON_BATCH_MAX_PAGES];
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};
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static u64 vmballoon_batch_get_pa(struct vmballoon_batch_page *batch, int idx)
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{
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return batch->pages[idx] & VMW_BALLOON_BATCH_PAGE_MASK;
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}
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static int vmballoon_batch_get_status(struct vmballoon_batch_page *batch,
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int idx)
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{
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return (int)(batch->pages[idx] & VMW_BALLOON_BATCH_STATUS_MASK);
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}
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static void vmballoon_batch_set_pa(struct vmballoon_batch_page *batch, int idx,
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u64 pa)
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{
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batch->pages[idx] = pa;
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}
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#define VMWARE_BALLOON_CMD(cmd, arg1, arg2, result) \
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({ \
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unsigned long __status, __dummy1, __dummy2; \
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unsigned long __status, __dummy1, __dummy2, __dummy3; \
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__asm__ __volatile__ ("inl %%dx" : \
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"=a"(__status), \
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"=c"(__dummy1), \
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"=d"(__dummy2), \
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"=b"(result) : \
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"=b"(result), \
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"=S" (__dummy3) : \
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"0"(VMW_BALLOON_HV_MAGIC), \
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"1"(VMW_BALLOON_CMD_##cmd), \
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"2"(VMW_BALLOON_HV_PORT), \
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"3"(data) : \
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"3"(arg1), \
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"4" (arg2) : \
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"memory"); \
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if (VMW_BALLOON_CMD_##cmd == VMW_BALLOON_CMD_START) \
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result = __dummy1; \
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@ -192,6 +251,14 @@ struct vmballoon_stats {
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#define STATS_INC(stat)
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#endif
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struct vmballoon;
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struct vmballoon_ops {
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void (*add_page)(struct vmballoon *b, int idx, struct page *p);
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int (*lock)(struct vmballoon *b, unsigned int num_pages);
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int (*unlock)(struct vmballoon *b, unsigned int num_pages);
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};
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struct vmballoon {
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/* list of reserved physical pages */
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@ -215,6 +282,14 @@ struct vmballoon {
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/* slowdown page allocations for next few cycles */
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unsigned int slow_allocation_cycles;
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unsigned long capabilities;
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struct vmballoon_batch_page *batch_page;
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unsigned int batch_max_pages;
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struct page *page;
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const struct vmballoon_ops *ops;
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#ifdef CONFIG_DEBUG_FS
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/* statistics */
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struct vmballoon_stats stats;
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@ -234,16 +309,22 @@ static struct vmballoon balloon;
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* Send "start" command to the host, communicating supported version
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* of the protocol.
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*/
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static bool vmballoon_send_start(struct vmballoon *b)
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static bool vmballoon_send_start(struct vmballoon *b, unsigned long req_caps)
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{
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unsigned long status, capabilities;
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unsigned long status, capabilities, dummy = 0;
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STATS_INC(b->stats.start);
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status = VMWARE_BALLOON_CMD(START, VMW_BALLOON_CAPABILITIES,
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capabilities);
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if (status == VMW_BALLOON_SUCCESS)
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status = VMWARE_BALLOON_CMD(START, req_caps, dummy, capabilities);
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switch (status) {
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case VMW_BALLOON_SUCCESS_WITH_CAPABILITIES:
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b->capabilities = capabilities;
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return true;
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case VMW_BALLOON_SUCCESS:
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b->capabilities = VMW_BALLOON_BASIC_CMDS;
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return true;
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}
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pr_debug("%s - failed, hv returns %ld\n", __func__, status);
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STATS_INC(b->stats.start_fail);
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@ -273,9 +354,10 @@ static bool vmballoon_check_status(struct vmballoon *b, unsigned long status)
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*/
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static bool vmballoon_send_guest_id(struct vmballoon *b)
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{
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unsigned long status, dummy;
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unsigned long status, dummy = 0;
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status = VMWARE_BALLOON_CMD(GUEST_ID, VMW_BALLOON_GUEST_ID, dummy);
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status = VMWARE_BALLOON_CMD(GUEST_ID, VMW_BALLOON_GUEST_ID, dummy,
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dummy);
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STATS_INC(b->stats.guest_type);
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@ -295,6 +377,7 @@ static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
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unsigned long status;
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unsigned long target;
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unsigned long limit;
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unsigned long dummy = 0;
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u32 limit32;
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/*
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@ -313,7 +396,7 @@ static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
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/* update stats */
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STATS_INC(b->stats.target);
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status = VMWARE_BALLOON_CMD(GET_TARGET, limit, target);
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status = VMWARE_BALLOON_CMD(GET_TARGET, limit, dummy, target);
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if (vmballoon_check_status(b, status)) {
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*new_target = target;
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return true;
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@ -332,7 +415,7 @@ static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
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static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
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unsigned int *hv_status)
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{
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unsigned long status, dummy;
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unsigned long status, dummy = 0;
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u32 pfn32;
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pfn32 = (u32)pfn;
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@ -341,7 +424,7 @@ static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
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STATS_INC(b->stats.lock);
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*hv_status = status = VMWARE_BALLOON_CMD(LOCK, pfn, dummy);
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*hv_status = status = VMWARE_BALLOON_CMD(LOCK, pfn, dummy, dummy);
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if (vmballoon_check_status(b, status))
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return 0;
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@ -350,13 +433,30 @@ static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
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return 1;
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}
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static int vmballoon_send_batched_lock(struct vmballoon *b,
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unsigned int num_pages)
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{
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unsigned long status, dummy;
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unsigned long pfn = page_to_pfn(b->page);
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STATS_INC(b->stats.lock);
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status = VMWARE_BALLOON_CMD(BATCHED_LOCK, pfn, num_pages, dummy);
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if (vmballoon_check_status(b, status))
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return 0;
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pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status);
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STATS_INC(b->stats.lock_fail);
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return 1;
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}
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/*
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* Notify the host that guest intends to release given page back into
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* the pool of available (to the guest) pages.
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*/
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static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn)
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{
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unsigned long status, dummy;
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unsigned long status, dummy = 0;
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u32 pfn32;
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pfn32 = (u32)pfn;
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@ -365,7 +465,7 @@ static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn)
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STATS_INC(b->stats.unlock);
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status = VMWARE_BALLOON_CMD(UNLOCK, pfn, dummy);
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status = VMWARE_BALLOON_CMD(UNLOCK, pfn, dummy, dummy);
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if (vmballoon_check_status(b, status))
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return true;
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@ -374,6 +474,23 @@ static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn)
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return false;
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}
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static bool vmballoon_send_batched_unlock(struct vmballoon *b,
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unsigned int num_pages)
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{
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unsigned long status, dummy;
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unsigned long pfn = page_to_pfn(b->page);
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STATS_INC(b->stats.unlock);
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status = VMWARE_BALLOON_CMD(BATCHED_UNLOCK, pfn, num_pages, dummy);
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if (vmballoon_check_status(b, status))
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return true;
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pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status);
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STATS_INC(b->stats.unlock_fail);
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return false;
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}
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/*
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* Quickly release all pages allocated for the balloon. This function is
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* called when host decides to "reset" balloon for one reason or another.
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@ -396,22 +513,13 @@ static void vmballoon_pop(struct vmballoon *b)
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cond_resched();
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}
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}
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}
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/*
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* Perform standard reset sequence by popping the balloon (in case it
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* is not empty) and then restarting protocol. This operation normally
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* happens when host responds with VMW_BALLOON_ERROR_RESET to a command.
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*/
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static void vmballoon_reset(struct vmballoon *b)
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{
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/* free all pages, skipping monitor unlock */
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vmballoon_pop(b);
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if ((b->capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) {
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if (b->batch_page)
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vunmap(b->batch_page);
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if (vmballoon_send_start(b)) {
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b->reset_required = false;
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if (!vmballoon_send_guest_id(b))
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pr_err("failed to send guest ID to the host\n");
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if (b->page)
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__free_page(b->page);
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}
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}
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@ -420,9 +528,10 @@ static void vmballoon_reset(struct vmballoon *b)
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* refuse list, those refused page are then released at the end of the
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* inflation cycle.
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*/
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static int vmballoon_lock_page(struct vmballoon *b, struct page *page)
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static int vmballoon_lock_page(struct vmballoon *b, unsigned int num_pages)
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{
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int locked, hv_status;
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struct page *page = b->page;
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locked = vmballoon_send_lock_page(b, page_to_pfn(page), &hv_status);
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if (locked > 0) {
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@ -457,17 +566,68 @@ static int vmballoon_lock_page(struct vmballoon *b, struct page *page)
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return 0;
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}
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static int vmballoon_lock_batched_page(struct vmballoon *b,
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unsigned int num_pages)
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{
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int locked, i;
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locked = vmballoon_send_batched_lock(b, num_pages);
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if (locked > 0) {
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for (i = 0; i < num_pages; i++) {
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u64 pa = vmballoon_batch_get_pa(b->batch_page, i);
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struct page *p = pfn_to_page(pa >> PAGE_SHIFT);
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__free_page(p);
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}
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return -EIO;
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}
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for (i = 0; i < num_pages; i++) {
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u64 pa = vmballoon_batch_get_pa(b->batch_page, i);
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struct page *p = pfn_to_page(pa >> PAGE_SHIFT);
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locked = vmballoon_batch_get_status(b->batch_page, i);
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switch (locked) {
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case VMW_BALLOON_SUCCESS:
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list_add(&p->lru, &b->pages);
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b->size++;
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break;
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case VMW_BALLOON_ERROR_PPN_PINNED:
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case VMW_BALLOON_ERROR_PPN_INVALID:
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if (b->n_refused_pages < VMW_BALLOON_MAX_REFUSED) {
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list_add(&p->lru, &b->refused_pages);
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b->n_refused_pages++;
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break;
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}
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/* Fallthrough */
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case VMW_BALLOON_ERROR_RESET:
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case VMW_BALLOON_ERROR_PPN_NOTNEEDED:
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__free_page(p);
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break;
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default:
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/* This should never happen */
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WARN_ON_ONCE(true);
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}
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}
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return 0;
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}
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/*
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* Release the page allocated for the balloon. Note that we first notify
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* the host so it can make sure the page will be available for the guest
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* to use, if needed.
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*/
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static int vmballoon_release_page(struct vmballoon *b, struct page *page)
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static int vmballoon_unlock_page(struct vmballoon *b, unsigned int num_pages)
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{
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if (!vmballoon_send_unlock_page(b, page_to_pfn(page)))
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return -EIO;
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struct page *page = b->page;
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list_del(&page->lru);
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if (!vmballoon_send_unlock_page(b, page_to_pfn(page))) {
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list_add(&page->lru, &b->pages);
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return -EIO;
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}
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/* deallocate page */
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__free_page(page);
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@ -479,6 +639,41 @@ static int vmballoon_release_page(struct vmballoon *b, struct page *page)
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return 0;
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}
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static int vmballoon_unlock_batched_page(struct vmballoon *b,
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unsigned int num_pages)
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{
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int locked, i, ret = 0;
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bool hv_success;
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hv_success = vmballoon_send_batched_unlock(b, num_pages);
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if (!hv_success)
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ret = -EIO;
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for (i = 0; i < num_pages; i++) {
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u64 pa = vmballoon_batch_get_pa(b->batch_page, i);
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struct page *p = pfn_to_page(pa >> PAGE_SHIFT);
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locked = vmballoon_batch_get_status(b->batch_page, i);
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if (!hv_success || locked != VMW_BALLOON_SUCCESS) {
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/*
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* That page wasn't successfully unlocked by the
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* hypervisor, re-add it to the list of pages owned by
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* the balloon driver.
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*/
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list_add(&p->lru, &b->pages);
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} else {
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/* deallocate page */
|
||||
__free_page(p);
|
||||
STATS_INC(b->stats.free);
|
||||
|
||||
/* update balloon size */
|
||||
b->size--;
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Release pages that were allocated while attempting to inflate the
|
||||
* balloon but were refused by the host for one reason or another.
|
||||
@ -496,6 +691,18 @@ static void vmballoon_release_refused_pages(struct vmballoon *b)
|
||||
b->n_refused_pages = 0;
|
||||
}
|
||||
|
||||
static void vmballoon_add_page(struct vmballoon *b, int idx, struct page *p)
|
||||
{
|
||||
b->page = p;
|
||||
}
|
||||
|
||||
static void vmballoon_add_batched_page(struct vmballoon *b, int idx,
|
||||
struct page *p)
|
||||
{
|
||||
vmballoon_batch_set_pa(b->batch_page, idx,
|
||||
(u64)page_to_pfn(p) << PAGE_SHIFT);
|
||||
}
|
||||
|
||||
/*
|
||||
* Inflate the balloon towards its target size. Note that we try to limit
|
||||
* the rate of allocation to make sure we are not choking the rest of the
|
||||
@ -507,6 +714,7 @@ static void vmballoon_inflate(struct vmballoon *b)
|
||||
unsigned int rate;
|
||||
unsigned int i;
|
||||
unsigned int allocations = 0;
|
||||
unsigned int num_pages = 0;
|
||||
int error = 0;
|
||||
gfp_t flags = VMW_PAGE_ALLOC_NOSLEEP;
|
||||
|
||||
@ -539,14 +747,13 @@ static void vmballoon_inflate(struct vmballoon *b)
|
||||
__func__, goal, rate, b->rate_alloc);
|
||||
|
||||
for (i = 0; i < goal; i++) {
|
||||
struct page *page;
|
||||
struct page *page = alloc_page(flags);
|
||||
|
||||
if (flags == VMW_PAGE_ALLOC_NOSLEEP)
|
||||
STATS_INC(b->stats.alloc);
|
||||
else
|
||||
STATS_INC(b->stats.sleep_alloc);
|
||||
|
||||
page = alloc_page(flags);
|
||||
if (!page) {
|
||||
if (flags == VMW_PAGE_ALLOC_CANSLEEP) {
|
||||
/*
|
||||
@ -580,9 +787,13 @@ static void vmballoon_inflate(struct vmballoon *b)
|
||||
continue;
|
||||
}
|
||||
|
||||
error = vmballoon_lock_page(b, page);
|
||||
if (error)
|
||||
break;
|
||||
b->ops->add_page(b, num_pages++, page);
|
||||
if (num_pages == b->batch_max_pages) {
|
||||
error = b->ops->lock(b, num_pages);
|
||||
num_pages = 0;
|
||||
if (error)
|
||||
break;
|
||||
}
|
||||
|
||||
if (++allocations > VMW_BALLOON_YIELD_THRESHOLD) {
|
||||
cond_resched();
|
||||
@ -595,6 +806,9 @@ static void vmballoon_inflate(struct vmballoon *b)
|
||||
}
|
||||
}
|
||||
|
||||
if (num_pages > 0)
|
||||
b->ops->lock(b, num_pages);
|
||||
|
||||
/*
|
||||
* We reached our goal without failures so try increasing
|
||||
* allocation rate.
|
||||
@ -618,6 +832,7 @@ static void vmballoon_deflate(struct vmballoon *b)
|
||||
struct page *page, *next;
|
||||
unsigned int i = 0;
|
||||
unsigned int goal;
|
||||
unsigned int num_pages = 0;
|
||||
int error;
|
||||
|
||||
pr_debug("%s - size: %d, target %d\n", __func__, b->size, b->target);
|
||||
@ -629,21 +844,94 @@ static void vmballoon_deflate(struct vmballoon *b)
|
||||
|
||||
/* free pages to reach target */
|
||||
list_for_each_entry_safe(page, next, &b->pages, lru) {
|
||||
error = vmballoon_release_page(b, page);
|
||||
if (error) {
|
||||
/* quickly decrease rate in case of error */
|
||||
b->rate_free = max(b->rate_free / 2,
|
||||
VMW_BALLOON_RATE_FREE_MIN);
|
||||
return;
|
||||
list_del(&page->lru);
|
||||
b->ops->add_page(b, num_pages++, page);
|
||||
|
||||
if (num_pages == b->batch_max_pages) {
|
||||
error = b->ops->unlock(b, num_pages);
|
||||
num_pages = 0;
|
||||
if (error) {
|
||||
/* quickly decrease rate in case of error */
|
||||
b->rate_free = max(b->rate_free / 2,
|
||||
VMW_BALLOON_RATE_FREE_MIN);
|
||||
return;
|
||||
}
|
||||
}
|
||||
|
||||
if (++i >= goal)
|
||||
break;
|
||||
}
|
||||
|
||||
if (num_pages > 0)
|
||||
b->ops->unlock(b, num_pages);
|
||||
|
||||
/* slowly increase rate if there were no errors */
|
||||
b->rate_free = min(b->rate_free + VMW_BALLOON_RATE_FREE_INC,
|
||||
VMW_BALLOON_RATE_FREE_MAX);
|
||||
if (error == 0)
|
||||
b->rate_free = min(b->rate_free + VMW_BALLOON_RATE_FREE_INC,
|
||||
VMW_BALLOON_RATE_FREE_MAX);
|
||||
}
|
||||
|
||||
static const struct vmballoon_ops vmballoon_basic_ops = {
|
||||
.add_page = vmballoon_add_page,
|
||||
.lock = vmballoon_lock_page,
|
||||
.unlock = vmballoon_unlock_page
|
||||
};
|
||||
|
||||
static const struct vmballoon_ops vmballoon_batched_ops = {
|
||||
.add_page = vmballoon_add_batched_page,
|
||||
.lock = vmballoon_lock_batched_page,
|
||||
.unlock = vmballoon_unlock_batched_page
|
||||
};
|
||||
|
||||
static bool vmballoon_init_batching(struct vmballoon *b)
|
||||
{
|
||||
b->page = alloc_page(VMW_PAGE_ALLOC_NOSLEEP);
|
||||
if (!b->page)
|
||||
return false;
|
||||
|
||||
b->batch_page = vmap(&b->page, 1, VM_MAP, PAGE_KERNEL);
|
||||
if (!b->batch_page) {
|
||||
__free_page(b->page);
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform standard reset sequence by popping the balloon (in case it
|
||||
* is not empty) and then restarting protocol. This operation normally
|
||||
* happens when host responds with VMW_BALLOON_ERROR_RESET to a command.
|
||||
*/
|
||||
static void vmballoon_reset(struct vmballoon *b)
|
||||
{
|
||||
/* free all pages, skipping monitor unlock */
|
||||
vmballoon_pop(b);
|
||||
|
||||
if (!vmballoon_send_start(b, VMW_BALLOON_CAPABILITIES))
|
||||
return;
|
||||
|
||||
if ((b->capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) {
|
||||
b->ops = &vmballoon_batched_ops;
|
||||
b->batch_max_pages = VMW_BALLOON_BATCH_MAX_PAGES;
|
||||
if (!vmballoon_init_batching(b)) {
|
||||
/*
|
||||
* We failed to initialize batching, inform the monitor
|
||||
* about it by sending a null capability.
|
||||
*
|
||||
* The guest will retry in one second.
|
||||
*/
|
||||
vmballoon_send_start(b, 0);
|
||||
return;
|
||||
}
|
||||
} else if ((b->capabilities & VMW_BALLOON_BASIC_CMDS) != 0) {
|
||||
b->ops = &vmballoon_basic_ops;
|
||||
b->batch_max_pages = 1;
|
||||
}
|
||||
|
||||
b->reset_required = false;
|
||||
if (!vmballoon_send_guest_id(b))
|
||||
pr_err("failed to send guest ID to the host\n");
|
||||
}
|
||||
|
||||
/*
|
||||
@ -802,11 +1090,23 @@ static int __init vmballoon_init(void)
|
||||
/*
|
||||
* Start balloon.
|
||||
*/
|
||||
if (!vmballoon_send_start(&balloon)) {
|
||||
if (!vmballoon_send_start(&balloon, VMW_BALLOON_CAPABILITIES)) {
|
||||
pr_err("failed to send start command to the host\n");
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
if ((balloon.capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) {
|
||||
balloon.ops = &vmballoon_batched_ops;
|
||||
balloon.batch_max_pages = VMW_BALLOON_BATCH_MAX_PAGES;
|
||||
if (!vmballoon_init_batching(&balloon)) {
|
||||
pr_err("failed to init batching\n");
|
||||
return -EIO;
|
||||
}
|
||||
} else if ((balloon.capabilities & VMW_BALLOON_BASIC_CMDS) != 0) {
|
||||
balloon.ops = &vmballoon_basic_ops;
|
||||
balloon.batch_max_pages = 1;
|
||||
}
|
||||
|
||||
if (!vmballoon_send_guest_id(&balloon)) {
|
||||
pr_err("failed to send guest ID to the host\n");
|
||||
return -EIO;
|
||||
@ -833,7 +1133,7 @@ static void __exit vmballoon_exit(void)
|
||||
* Reset connection before deallocating memory to avoid potential for
|
||||
* additional spurious resets from guest touching deallocated pages.
|
||||
*/
|
||||
vmballoon_send_start(&balloon);
|
||||
vmballoon_send_start(&balloon, VMW_BALLOON_CAPABILITIES);
|
||||
vmballoon_pop(&balloon);
|
||||
}
|
||||
module_exit(vmballoon_exit);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user