From 61af111810219339d4029bb9a35ff930feb3ec49 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 22 Feb 2013 17:36:45 +0100 Subject: [PATCH 243/246] migration: move rate limiting to QEMUFile Rate limiting is now simply a byte counter; client call qemu_file_rate_limit() manually to determine if they have to exit. So it is possible and simple to move the functionality to QEMUFile. This makes the remaining functionality of s->file redundant; in the next patch we can remove it and write directly to s->migration_file. Reviewed-by: Orit Wasserman Reviewed-by: Juan Quintela Signed-off-by: Paolo Bonzini Signed-off-by: Juan Quintela --- docs/migration.txt | 20 +---------------- include/migration/qemu-file.h | 18 ++------------- migration.c | 51 +------------------------------------------ savevm.c | 31 ++++++++++++++------------ 4 files changed, 21 insertions(+), 99 deletions(-) diff --git a/docs/migration.txt b/docs/migration.txt index f3ddd2f..0719a55 100644 --- a/docs/migration.txt +++ b/docs/migration.txt @@ -55,10 +55,7 @@ QEMUFile with: QEMUFile *qemu_fopen_ops(void *opaque, QEMUFilePutBufferFunc *put_buffer, QEMUFileGetBufferFunc *get_buffer, - QEMUFileCloseFunc *close, - QEMUFileRateLimit *rate_limit, - QEMUFileSetRateLimit *set_rate_limit, - QEMUFileGetRateLimit *get_rate_limit); + QEMUFileCloseFunc *close); The functions have the following functionality: @@ -80,24 +77,9 @@ Close a file and return an error code. typedef int (QEMUFileCloseFunc)(void *opaque); -Called to determine if the file has exceeded its bandwidth allocation. The -bandwidth capping is a soft limit, not a hard limit. - -typedef int (QEMUFileRateLimit)(void *opaque); - -Called to change the current bandwidth allocation. This function must return -the new actual bandwidth. It should be new_rate if everything goes OK, and -the old rate otherwise. - -typedef size_t (QEMUFileSetRateLimit)(void *opaque, size_t new_rate); -typedef size_t (QEMUFileGetRateLimit)(void *opaque); - You can use any internal state that you need using the opaque void * pointer that is passed to all functions. -The rate limiting functions are used to limit the bandwidth used by -QEMU migration. - The important functions for us are put_buffer()/get_buffer() that allow to write/read a buffer into the QEMUFile. diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h index 25e8461..df81261 100644 --- a/include/migration/qemu-file.h +++ b/include/migration/qemu-file.h @@ -51,26 +51,11 @@ typedef int (QEMUFileCloseFunc)(void *opaque); */ typedef int (QEMUFileGetFD)(void *opaque); -/* Called to determine if the file has exceeded its bandwidth allocation. The - * bandwidth capping is a soft limit, not a hard limit. - */ -typedef int (QEMUFileRateLimit)(void *opaque); - -/* Called to change the current bandwidth allocation. This function must return - * the new actual bandwidth. It should be new_rate if everything goes ok, and - * the old rate otherwise - */ -typedef int64_t (QEMUFileSetRateLimit)(void *opaque, int64_t new_rate); -typedef int64_t (QEMUFileGetRateLimit)(void *opaque); - typedef struct QEMUFileOps { QEMUFilePutBufferFunc *put_buffer; QEMUFileGetBufferFunc *get_buffer; QEMUFileCloseFunc *close; QEMUFileGetFD *get_fd; - QEMUFileRateLimit *rate_limit; - QEMUFileSetRateLimit *set_rate_limit; - QEMUFileGetRateLimit *get_rate_limit; } QEMUFileOps; QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops); @@ -109,7 +94,8 @@ unsigned int qemu_get_be32(QEMUFile *f); uint64_t qemu_get_be64(QEMUFile *f); int qemu_file_rate_limit(QEMUFile *f); -int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate); +void qemu_file_reset_rate_limit(QEMUFile *f); +void qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate); int64_t qemu_file_get_rate_limit(QEMUFile *f); int qemu_file_get_error(QEMUFile *f); diff --git a/migration.c b/migration.c index 5c7d04f..ea84008 100644 --- a/migration.c +++ b/migration.c @@ -518,7 +518,6 @@ static int migration_put_buffer(void *opaque, const uint8_t *buf, return ret; } - s->bytes_xfer += size; return size; } @@ -543,49 +542,6 @@ static int migration_get_fd(void *opaque) return qemu_get_fd(s->migration_file); } -/* - * The meaning of the return values is: - * 0: We can continue sending - * 1: Time to stop - * negative: There has been an error - */ -static int migration_rate_limit(void *opaque) -{ - MigrationState *s = opaque; - int ret; - - ret = qemu_file_get_error(s->file); - if (ret) { - return ret; - } - - if (s->bytes_xfer >= s->xfer_limit) { - return 1; - } - - return 0; -} - -static int64_t migration_set_rate_limit(void *opaque, int64_t new_rate) -{ - MigrationState *s = opaque; - if (qemu_file_get_error(s->file)) { - goto out; - } - - s->xfer_limit = new_rate; - -out: - return s->xfer_limit; -} - -static int64_t migration_get_rate_limit(void *opaque) -{ - MigrationState *s = opaque; - - return s->xfer_limit; -} - static void *migration_thread(void *opaque) { MigrationState *s = opaque; @@ -646,7 +602,7 @@ static void *migration_thread(void *opaque) s->expected_downtime = s->dirty_bytes_rate / bandwidth; } - s->bytes_xfer = 0; + qemu_file_reset_rate_limit(s->file); sleep_time = 0; initial_time = current_time; initial_bytes = qemu_ftell(s->file); @@ -679,9 +635,6 @@ static const QEMUFileOps migration_file_ops = { .get_fd = migration_get_fd, .put_buffer = migration_put_buffer, .close = migration_close, - .rate_limit = migration_rate_limit, - .get_rate_limit = migration_get_rate_limit, - .set_rate_limit = migration_set_rate_limit, }; void migrate_fd_connect(MigrationState *s) @@ -689,10 +642,8 @@ void migrate_fd_connect(MigrationState *s) s->state = MIG_STATE_ACTIVE; trace_migrate_set_state(MIG_STATE_ACTIVE); - s->bytes_xfer = 0; /* This is a best 1st approximation. ns to ms */ s->expected_downtime = max_downtime/1000000; - s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s); s->file = qemu_fopen_ops(s, &migration_file_ops); diff --git a/savevm.c b/savevm.c index 43963ce..e9471a5 100644 --- a/savevm.c +++ b/savevm.c @@ -119,6 +119,9 @@ struct QEMUFile { void *opaque; int is_write; + int64_t bytes_xfer; + int64_t xfer_limit; + int64_t pos; /* start of buffer when writing, end of buffer when reading */ int buf_index; @@ -479,7 +482,6 @@ QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops) f->opaque = opaque; f->ops = ops; f->is_write = 0; - return f; } @@ -605,6 +607,7 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) memcpy(f->buf + f->buf_index, buf, l); f->is_write = 1; f->buf_index += l; + f->bytes_xfer += l; buf += l; size -= l; if (f->buf_index >= IO_BUF_SIZE) { @@ -725,28 +728,28 @@ int64_t qemu_ftell(QEMUFile *f) int qemu_file_rate_limit(QEMUFile *f) { - if (f->ops->rate_limit) - return f->ops->rate_limit(f->opaque); - + if (qemu_file_get_error(f)) { + return 1; + } + if (f->xfer_limit > 0 && f->bytes_xfer > f->xfer_limit) { + return 1; + } return 0; } int64_t qemu_file_get_rate_limit(QEMUFile *f) { - if (f->ops->get_rate_limit) - return f->ops->get_rate_limit(f->opaque); - - return 0; + return f->xfer_limit; } -int64_t qemu_file_set_rate_limit(QEMUFile *f, int64_t new_rate) +void qemu_file_set_rate_limit(QEMUFile *f, int64_t limit) { - /* any failed or completed migration keeps its state to allow probing of - * migration data, but has no associated file anymore */ - if (f && f->ops->set_rate_limit) - return f->ops->set_rate_limit(f->opaque, new_rate); + f->xfer_limit = limit; +} - return 0; +void qemu_file_reset_rate_limit(QEMUFile *f) +{ + f->bytes_xfer = 0; } void qemu_put_be16(QEMUFile *f, unsigned int v) -- 1.8.2.1