migration/multifd.h - third_party/qemu - Git at Google

 /*
  * Multifd common functions
  *
  * Copyright (c) 2019-2020 Red Hat Inc
  *
  * Authors:
  *  Juan Quintela <quintela@redhat.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  */

 #ifndef QEMU_MIGRATION_MULTIFD_H
 #define QEMU_MIGRATION_MULTIFD_H

 #include "ram.h"

 typedef struct MultiFDRecvData MultiFDRecvData;

 bool multifd_send_setup(void);
 void multifd_send_shutdown(void);
 void multifd_send_channel_created(void);
 int multifd_recv_setup(Error **errp);
 void multifd_recv_cleanup(void);
 void multifd_recv_shutdown(void);
 bool multifd_recv_all_channels_created(void);
 void multifd_recv_new_channel(QIOChannel *ioc, Error **errp);
 void multifd_recv_sync_main(void);
 int multifd_send_sync_main(void);
 bool multifd_queue_page(RAMBlock *block, ram_addr_t offset);
 bool multifd_recv(void);
 MultiFDRecvData *multifd_get_recv_data(void);

 /* Multifd Compression flags */
 #define MULTIFD_FLAG_SYNC (1 << 0)

 /* We reserve 3 bits for compression methods */
 #define MULTIFD_FLAG_COMPRESSION_MASK (7 << 1)
 /* we need to be compatible. Before compression value was 0 */
 #define MULTIFD_FLAG_NOCOMP (0 << 1)
 #define MULTIFD_FLAG_ZLIB (1 << 1)
 #define MULTIFD_FLAG_ZSTD (2 << 1)

 /* This value needs to be a multiple of qemu_target_page_size() */
 #define MULTIFD_PACKET_SIZE (512 * 1024)

 typedef struct {
     uint32_t magic;
     uint32_t version;
     uint32_t flags;
     /* maximum number of allocated pages */
     uint32_t pages_alloc;
     /* non zero pages */
     uint32_t normal_pages;
     /* size of the next packet that contains pages */
     uint32_t next_packet_size;
     uint64_t packet_num;
     /* zero pages */
     uint32_t zero_pages;
     uint32_t unused32[1];    /* Reserved for future use */
     uint64_t unused64[3];    /* Reserved for future use */
     char ramblock[256];
     /*
      * This array contains the pointers to:
      *  - normal pages (initial normal_pages entries)
      *  - zero pages (following zero_pages entries)
      */
     uint64_t offset[];
 } __attribute__((packed)) MultiFDPacket_t;

 typedef struct {
     /* number of used pages */
     uint32_t num;
     /* number of normal pages */
     uint32_t normal_num;
     /* number of allocated pages */
     uint32_t allocated;
     /* offset of each page */
     ram_addr_t *offset;
     RAMBlock *block;
 } MultiFDPages_t;

 struct MultiFDRecvData {
     void *opaque;
     size_t size;
     /* for preadv */
     off_t file_offset;
 };

 typedef struct {
     /* Fields are only written at creating/deletion time */
     /* No lock required for them, they are read only */

     /* channel number */
     uint8_t id;
     /* channel thread name */
     char *name;
     /* channel thread id */
     QemuThread thread;
     bool thread_created;
     QemuThread tls_thread;
     bool tls_thread_created;
     /* communication channel */
     QIOChannel *c;
     /* packet allocated len */
     uint32_t packet_len;
     /* guest page size */
     uint32_t page_size;
     /* number of pages in a full packet */
     uint32_t page_count;
     /* multifd flags for sending ram */
     int write_flags;

     /* sem where to wait for more work */
     QemuSemaphore sem;
     /* syncs main thread and channels */
     QemuSemaphore sem_sync;

     /* multifd flags for each packet */
     uint32_t flags;
     /*
      * The sender thread has work to do if either of below boolean is set.
      *
      * @pending_job:  a job is pending
      * @pending_sync: a sync request is pending
      *
      * For both of these fields, they're only set by the requesters, and
      * cleared by the multifd sender threads.
      */
     bool pending_job;
     bool pending_sync;
     /* array of pages to sent.
      * The owner of 'pages' depends of 'pending_job' value:
      * pending_job == 0 -> migration_thread can use it.
      * pending_job != 0 -> multifd_channel can use it.
      */
     MultiFDPages_t *pages;

     /* thread local variables. No locking required */

     /* pointer to the packet */
     MultiFDPacket_t *packet;
     /* size of the next packet that contains pages */
     uint32_t next_packet_size;
     /* packets sent through this channel */
     uint64_t packets_sent;
     /* non zero pages sent through this channel */
     uint64_t total_normal_pages;
     /* zero pages sent through this channel */
     uint64_t total_zero_pages;
     /* buffers to send */
     struct iovec *iov;
     /* number of iovs used */
     uint32_t iovs_num;
     /* used for compression methods */
     void *compress_data;
 }  MultiFDSendParams;

 typedef struct {
     /* Fields are only written at creating/deletion time */
     /* No lock required for them, they are read only */

     /* channel number */
     uint8_t id;
     /* channel thread name */
     char *name;
     /* channel thread id */
     QemuThread thread;
     bool thread_created;
     /* communication channel */
     QIOChannel *c;
     /* packet allocated len */
     uint32_t packet_len;
     /* guest page size */
     uint32_t page_size;
     /* number of pages in a full packet */
     uint32_t page_count;

     /* syncs main thread and channels */
     QemuSemaphore sem_sync;
     /* sem where to wait for more work */
     QemuSemaphore sem;

     /* this mutex protects the following parameters */
     QemuMutex mutex;
     /* should this thread finish */
     bool quit;
     /* multifd flags for each packet */
     uint32_t flags;
     /* global number of generated multifd packets */
     uint64_t packet_num;
     int pending_job;
     MultiFDRecvData *data;

     /* thread local variables. No locking required */

     /* pointer to the packet */
     MultiFDPacket_t *packet;
     /* size of the next packet that contains pages */
     uint32_t next_packet_size;
     /* packets received through this channel */
     uint64_t packets_recved;
     /* ramblock */
     RAMBlock *block;
     /* ramblock host address */
     uint8_t *host;
     /* non zero pages recv through this channel */
     uint64_t total_normal_pages;
     /* zero pages recv through this channel */
     uint64_t total_zero_pages;
     /* buffers to recv */
     struct iovec *iov;
     /* Pages that are not zero */
     ram_addr_t *normal;
     /* num of non zero pages */
     uint32_t normal_num;
     /* Pages that are zero */
     ram_addr_t *zero;
     /* num of zero pages */
     uint32_t zero_num;
     /* used for de-compression methods */
     void *compress_data;
 } MultiFDRecvParams;

 typedef struct {
     /* Setup for sending side */
     int (*send_setup)(MultiFDSendParams *p, Error **errp);
     /* Cleanup for sending side */
     void (*send_cleanup)(MultiFDSendParams *p, Error **errp);
     /* Prepare the send packet */
     int (*send_prepare)(MultiFDSendParams *p, Error **errp);
     /* Setup for receiving side */
     int (*recv_setup)(MultiFDRecvParams *p, Error **errp);
     /* Cleanup for receiving side */
     void (*recv_cleanup)(MultiFDRecvParams *p);
     /* Read all data */
     int (*recv)(MultiFDRecvParams *p, Error **errp);
 } MultiFDMethods;

 void multifd_register_ops(int method, MultiFDMethods *ops);
 void multifd_send_fill_packet(MultiFDSendParams *p);
 bool multifd_send_prepare_common(MultiFDSendParams *p);
 void multifd_send_zero_page_detect(MultiFDSendParams *p);
 void multifd_recv_zero_page_process(MultiFDRecvParams *p);

 static inline void multifd_send_prepare_header(MultiFDSendParams *p)
 {
     p->iov[0].iov_len = p->packet_len;
     p->iov[0].iov_base = p->packet;
     p->iovs_num++;
 }

 void multifd_channel_connect(MultiFDSendParams *p, QIOChannel *ioc);

 #endif
	/*
	* Multifd common functions
	*
	* Copyright (c) 2019-2020 Red Hat Inc
	*
	* Authors:
	* Juan Quintela <quintela@redhat.com>
	*
	* This work is licensed under the terms of the GNU GPL, version 2 or later.
	* See the COPYING file in the top-level directory.
	*/

	#ifndef QEMU_MIGRATION_MULTIFD_H
	#define QEMU_MIGRATION_MULTIFD_H

	#include "ram.h"

	typedef struct MultiFDRecvData MultiFDRecvData;

	bool multifd_send_setup(void);
	void multifd_send_shutdown(void);
	void multifd_send_channel_created(void);
	int multifd_recv_setup(Error **errp);
	void multifd_recv_cleanup(void);
	void multifd_recv_shutdown(void);
	bool multifd_recv_all_channels_created(void);
	void multifd_recv_new_channel(QIOChannel ioc, Error *errp);
	void multifd_recv_sync_main(void);
	int multifd_send_sync_main(void);
	bool multifd_queue_page(RAMBlock *block, ram_addr_t offset);
	bool multifd_recv(void);
	MultiFDRecvData *multifd_get_recv_data(void);

	/* Multifd Compression flags */
	#define MULTIFD_FLAG_SYNC (1 << 0)

	/* We reserve 3 bits for compression methods */
	#define MULTIFD_FLAG_COMPRESSION_MASK (7 << 1)
	/* we need to be compatible. Before compression value was 0 */
	#define MULTIFD_FLAG_NOCOMP (0 << 1)
	#define MULTIFD_FLAG_ZLIB (1 << 1)
	#define MULTIFD_FLAG_ZSTD (2 << 1)

	/* This value needs to be a multiple of qemu_target_page_size() */
	#define MULTIFD_PACKET_SIZE (512 * 1024)

	typedef struct {
	uint32_t magic;
	uint32_t version;
	uint32_t flags;
	/* maximum number of allocated pages */
	uint32_t pages_alloc;
	/* non zero pages */
	uint32_t normal_pages;
	/* size of the next packet that contains pages */
	uint32_t next_packet_size;
	uint64_t packet_num;
	/* zero pages */
	uint32_t zero_pages;
	uint32_t unused32[1]; /* Reserved for future use */
	uint64_t unused64[3]; /* Reserved for future use */
	char ramblock[256];
	/*
	* This array contains the pointers to:
	* - normal pages (initial normal_pages entries)
	* - zero pages (following zero_pages entries)
	*/
	uint64_t offset[];
	} __attribute__((packed)) MultiFDPacket_t;

	typedef struct {
	/* number of used pages */
	uint32_t num;
	/* number of normal pages */
	uint32_t normal_num;
	/* number of allocated pages */
	uint32_t allocated;
	/* offset of each page */
	ram_addr_t *offset;
	RAMBlock *block;
	} MultiFDPages_t;

	struct MultiFDRecvData {
	void *opaque;
	size_t size;
	/* for preadv */
	off_t file_offset;
	};

	typedef struct {
	/* Fields are only written at creating/deletion time */
	/* No lock required for them, they are read only */

	/* channel number */
	uint8_t id;
	/* channel thread name */
	char *name;
	/* channel thread id */
	QemuThread thread;
	bool thread_created;
	QemuThread tls_thread;
	bool tls_thread_created;
	/* communication channel */
	QIOChannel *c;
	/* packet allocated len */
	uint32_t packet_len;
	/* guest page size */
	uint32_t page_size;
	/* number of pages in a full packet */
	uint32_t page_count;
	/* multifd flags for sending ram */
	int write_flags;

	/* sem where to wait for more work */
	QemuSemaphore sem;
	/* syncs main thread and channels */
	QemuSemaphore sem_sync;

	/* multifd flags for each packet */
	uint32_t flags;
	/*
	* The sender thread has work to do if either of below boolean is set.
	*
	* @pending_job: a job is pending
	* @pending_sync: a sync request is pending
	*
	* For both of these fields, they're only set by the requesters, and
	* cleared by the multifd sender threads.
	*/
	bool pending_job;
	bool pending_sync;
	/* array of pages to sent.
	* The owner of 'pages' depends of 'pending_job' value:
	* pending_job == 0 -> migration_thread can use it.
	* pending_job != 0 -> multifd_channel can use it.
	*/
	MultiFDPages_t *pages;

	/* thread local variables. No locking required */

	/* pointer to the packet */
	MultiFDPacket_t *packet;
	/* size of the next packet that contains pages */
	uint32_t next_packet_size;
	/* packets sent through this channel */
	uint64_t packets_sent;
	/* non zero pages sent through this channel */
	uint64_t total_normal_pages;
	/* zero pages sent through this channel */
	uint64_t total_zero_pages;
	/* buffers to send */
	struct iovec *iov;
	/* number of iovs used */
	uint32_t iovs_num;
	/* used for compression methods */
	void *compress_data;
	} MultiFDSendParams;

	typedef struct {
	/* Fields are only written at creating/deletion time */
	/* No lock required for them, they are read only */

	/* channel number */
	uint8_t id;
	/* channel thread name */
	char *name;
	/* channel thread id */
	QemuThread thread;
	bool thread_created;
	/* communication channel */
	QIOChannel *c;
	/* packet allocated len */
	uint32_t packet_len;
	/* guest page size */
	uint32_t page_size;
	/* number of pages in a full packet */
	uint32_t page_count;

	/* syncs main thread and channels */
	QemuSemaphore sem_sync;
	/* sem where to wait for more work */
	QemuSemaphore sem;

	/* this mutex protects the following parameters */
	QemuMutex mutex;
	/* should this thread finish */
	bool quit;
	/* multifd flags for each packet */
	uint32_t flags;
	/* global number of generated multifd packets */
	uint64_t packet_num;
	int pending_job;
	MultiFDRecvData *data;

	/* thread local variables. No locking required */

	/* pointer to the packet */
	MultiFDPacket_t *packet;
	/* size of the next packet that contains pages */
	uint32_t next_packet_size;
	/* packets received through this channel */
	uint64_t packets_recved;
	/* ramblock */
	RAMBlock *block;
	/* ramblock host address */
	uint8_t *host;
	/* non zero pages recv through this channel */
	uint64_t total_normal_pages;
	/* zero pages recv through this channel */
	uint64_t total_zero_pages;
	/* buffers to recv */
	struct iovec *iov;
	/* Pages that are not zero */
	ram_addr_t *normal;
	/* num of non zero pages */
	uint32_t normal_num;
	/* Pages that are zero */
	ram_addr_t *zero;
	/* num of zero pages */
	uint32_t zero_num;
	/* used for de-compression methods */
	void *compress_data;
	} MultiFDRecvParams;

	typedef struct {
	/* Setup for sending side */
	int (send_setup)(MultiFDSendParams p, Error **errp);
	/* Cleanup for sending side */
	void (send_cleanup)(MultiFDSendParams p, Error **errp);
	/* Prepare the send packet */
	int (send_prepare)(MultiFDSendParams p, Error **errp);
	/* Setup for receiving side */
	int (recv_setup)(MultiFDRecvParams p, Error **errp);
	/* Cleanup for receiving side */
	void (recv_cleanup)(MultiFDRecvParams p);
	/* Read all data */
	int (recv)(MultiFDRecvParams p, Error **errp);
	} MultiFDMethods;

	void multifd_register_ops(int method, MultiFDMethods *ops);
	void multifd_send_fill_packet(MultiFDSendParams *p);
	bool multifd_send_prepare_common(MultiFDSendParams *p);
	void multifd_send_zero_page_detect(MultiFDSendParams *p);
	void multifd_recv_zero_page_process(MultiFDRecvParams *p);

	static inline void multifd_send_prepare_header(MultiFDSendParams *p)
	{
	p->iov[0].iov_len = p->packet_len;
	p->iov[0].iov_base = p->packet;
	p->iovs_num++;
	}

	void multifd_channel_connect(MultiFDSendParams p, QIOChannel ioc);

	#endif