Re: [Qemu-devel] [PATCH 16/30] migration: move buffered_file.c code into migration.c

[Paolo Bonzini <pbonzini@redhat.com>]

Il 18/10/2012 09:30, Juan Quintela ha scritto:
> This only moves the code (also from buffered_file.h to migration.h).
> Fix whitespace until checkpatch is happy.

While I agree with this patch, it is also a conflict magnet.  My
migration-in-a-coroutine cleanups will touch buffered_file.c, you're
warned...

Paolo

> Signed-off-by: Juan Quintela <quintela@redhat.com>
> ---
>  Makefile.objs   |   2 +-
>  buffered_file.c | 244 --------------------------------------------------------
>  buffered_file.h |  22 -----
>  migration.c     | 218 +++++++++++++++++++++++++++++++++++++++++++++++++-
>  migration.h     |   1 +
>  5 files changed, 219 insertions(+), 268 deletions(-)
>  delete mode 100644 buffered_file.c
>  delete mode 100644 buffered_file.h
> 
> diff --git a/Makefile.objs b/Makefile.objs
> index 74b3542..3de8f27 100644
> --- a/Makefile.objs
> +++ b/Makefile.objs
> @@ -73,7 +73,7 @@ extra-obj-$(CONFIG_LINUX) += fsdev/
> 
>  common-obj-y += tcg-runtime.o host-utils.o main-loop.o
>  common-obj-y += input.o
> -common-obj-y += buffered_file.o migration.o migration-tcp.o
> +common-obj-y += migration.o migration-tcp.o
>  common-obj-y += qemu-char.o #aio.o
>  common-obj-y += block-migration.o iohandler.o
>  common-obj-y += pflib.o
> diff --git a/buffered_file.c b/buffered_file.c
> deleted file mode 100644
> index c21f847..0000000
> --- a/buffered_file.c
> +++ /dev/null
> @@ -1,244 +0,0 @@
> -/*
> - * QEMU buffered QEMUFile
> - *
> - * Copyright IBM, Corp. 2008
> - *
> - * Authors:
> - *  Anthony Liguori   <aliguori@us.ibm.com>
> - *
> - * This work is licensed under the terms of the GNU GPL, version 2.  See
> - * the COPYING file in the top-level directory.
> - *
> - * Contributions after 2012-01-13 are licensed under the terms of the
> - * GNU GPL, version 2 or (at your option) any later version.
> - */
> -
> -#include "qemu-common.h"
> -#include "hw/hw.h"
> -#include "qemu-timer.h"
> -#include "qemu-char.h"
> -#include "buffered_file.h"
> -#include "qemu-thread.h"
> -
> -//#define DEBUG_BUFFERED_FILE
> -
> -typedef struct QEMUFileBuffered
> -{
> -    MigrationState *migration_state;
> -    QEMUFile *file;
> -    size_t bytes_xfer;
> -    size_t xfer_limit;
> -    uint8_t *buffer;
> -    size_t buffer_size;
> -    size_t buffer_capacity;
> -    QemuThread thread;
> -} QEMUFileBuffered;
> -
> -#ifdef DEBUG_BUFFERED_FILE
> -#define DPRINTF(fmt, ...) \
> -    do { printf("buffered-file: " fmt, ## __VA_ARGS__); } while (0)
> -#else
> -#define DPRINTF(fmt, ...) \
> -    do { } while (0)
> -#endif
> -
> -static ssize_t buffered_flush(QEMUFileBuffered *s)
> -{
> -    size_t offset = 0;
> -    ssize_t ret = 0;
> -
> -    DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
> -
> -    while (s->bytes_xfer < s->xfer_limit && offset < s->buffer_size) {
> -
> -        ret = migrate_fd_put_buffer(s->migration_state, s->buffer + offset,
> -                                    s->buffer_size - offset);
> -        if (ret <= 0) {
> -            DPRINTF("error flushing data, %zd\n", ret);
> -            break;
> -        } else {
> -            DPRINTF("flushed %zd byte(s)\n", ret);
> -            offset += ret;
> -            s->bytes_xfer += ret;
> -        }
> -    }
> -
> -    DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
> -    memmove(s->buffer, s->buffer + offset, s->buffer_size - offset);
> -    s->buffer_size -= offset;
> -
> -    if (ret < 0) {
> -        return ret;
> -    }
> -    return offset;
> -}
> -
> -static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size)
> -{
> -    QEMUFileBuffered *s = opaque;
> -    ssize_t error;
> -
> -    DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos);
> -
> -    error = qemu_file_get_error(s->file);
> -    if (error) {
> -        DPRINTF("flush when error, bailing: %s\n", strerror(-error));
> -        return error;
> -    }
> -
> -    if (size <= 0) {
> -        return size;
> -    }
> -
> -    if (size > (s->buffer_capacity - s->buffer_size)) {
> -        DPRINTF("increasing buffer capacity from %zu by %zu\n",
> -                s->buffer_capacity, size + 1024);
> -
> -        s->buffer_capacity += size + 1024;
> -
> -        s->buffer = g_realloc(s->buffer, s->buffer_capacity);
> -    }
> -
> -    memcpy(s->buffer + s->buffer_size, buf, size);
> -    s->buffer_size += size;
> -
> -    return size;
> -}
> -
> -static int buffered_close(void *opaque)
> -{
> -    QEMUFileBuffered *s = opaque;
> -    ssize_t ret = 0;
> -    int ret2;
> -
> -    DPRINTF("closing\n");
> -
> -    s->xfer_limit = INT_MAX;
> -    while (!qemu_file_get_error(s->file) && s->buffer_size) {
> -        ret = buffered_flush(s);
> -        if (ret < 0) {
> -            break;
> -        }
> -    }
> -
> -    ret2 = migrate_fd_close(s->migration_state);
> -    if (ret >= 0) {
> -        ret = ret2;
> -    }
> -    ret = migrate_fd_close(s->migration_state);
> -    s->migration_state->complete = true;
> -    return ret;
> -}
> -
> -/*
> - * The meaning of the return values is:
> - *   0: We can continue sending
> - *   1: Time to stop
> - *   negative: There has been an error
> - */
> -static int buffered_rate_limit(void *opaque)
> -{
> -    QEMUFileBuffered *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 buffered_set_rate_limit(void *opaque, int64_t new_rate)
> -{
> -    QEMUFileBuffered *s = opaque;
> -    if (qemu_file_get_error(s->file)) {
> -        goto out;
> -    }
> -    if (new_rate > SIZE_MAX) {
> -        new_rate = SIZE_MAX;
> -    }
> -
> -    s->xfer_limit = new_rate / 10;
> -    
> -out:
> -    return s->xfer_limit;
> -}
> -
> -static int64_t buffered_get_rate_limit(void *opaque)
> -{
> -    QEMUFileBuffered *s = opaque;
> -  
> -    return s->xfer_limit;
> -}
> -
> -/* 100ms  xfer_limit is the limit that we should write each 100ms */
> -#define BUFFER_DELAY 100
> -
> -static void *buffered_file_thread(void *opaque)
> -{
> -    QEMUFileBuffered *s = opaque;
> -    int64_t initial_time = qemu_get_clock_ms(rt_clock);
> -    int64_t max_size = 0;
> -    bool last_round = false;
> -
> -    while (true) {
> -        int64_t current_time = qemu_get_clock_ms(rt_clock);
> -
> -        if (s->migration_state->complete) {
> -            break;
> -        }
> -        if (current_time >= initial_time + BUFFER_DELAY) {
> -            uint64_t transferred_bytes = s->bytes_xfer;
> -            uint64_t time_spent = current_time - initial_time;
> -            double bandwidth = transferred_bytes / time_spent;
> -            max_size = bandwidth * migrate_max_downtime() / 1000000;
> -
> -            DPRINTF("transferred %" PRIu64 " time_spent %" PRIu64
> -                    " bandwidth %g max_size %" PRId64 "\n",
> -                    transferred_bytes, time_spent, bandwidth, max_size);
> -
> -            s->bytes_xfer = 0;
> -            initial_time = current_time;
> -        }
> -        if (!last_round && (s->bytes_xfer >= s->xfer_limit)) {
> -            /* usleep expects microseconds */
> -            usleep((initial_time + BUFFER_DELAY - current_time)*1000);
> -        }
> -        buffered_flush(s);
> -
> -        DPRINTF("file is ready\n");
> -        if (s->bytes_xfer < s->xfer_limit) {
> -            DPRINTF("notifying client\n");
> -            last_round = migrate_fd_put_ready(s->migration_state, max_size);
> -        }
> -    }
> -
> -    g_free(s->buffer);
> -    g_free(s);
> -    return NULL;
> -}
> -
> -void qemu_fopen_ops_buffered(MigrationState *migration_state)
> -{
> -    QEMUFileBuffered *s;
> -
> -    s = g_malloc0(sizeof(*s));
> -
> -    s->migration_state = migration_state;
> -    s->xfer_limit = migration_state->bandwidth_limit / 10;
> -    s->migration_state->complete = false;
> -
> -    s->file = qemu_fopen_ops(s, buffered_put_buffer, NULL,
> -                             buffered_close, buffered_rate_limit,
> -                             buffered_set_rate_limit,
> -			     buffered_get_rate_limit);
> -
> -    migration_state->file = s->file;
> -
> -    qemu_thread_create(&s->thread, buffered_file_thread, s,
> -                       QEMU_THREAD_DETACHED);
> -}
> diff --git a/buffered_file.h b/buffered_file.h
> deleted file mode 100644
> index 8a246fd..0000000
> --- a/buffered_file.h
> +++ /dev/null
> @@ -1,22 +0,0 @@
> -/*
> - * QEMU buffered QEMUFile
> - *
> - * Copyright IBM, Corp. 2008
> - *
> - * Authors:
> - *  Anthony Liguori   <aliguori@us.ibm.com>
> - *
> - * This work is licensed under the terms of the GNU GPL, version 2.  See
> - * the COPYING file in the top-level directory.
> - *
> - */
> -
> -#ifndef QEMU_BUFFERED_FILE_H
> -#define QEMU_BUFFERED_FILE_H
> -
> -#include "hw/hw.h"
> -#include "migration.h"
> -
> -void qemu_fopen_ops_buffered(MigrationState *migration_state);
> -
> -#endif
> diff --git a/migration.c b/migration.c
> index 8054a77..b1567f3 100644
> --- a/migration.c
> +++ b/migration.c
> @@ -16,7 +16,7 @@
>  #include "qemu-common.h"
>  #include "migration.h"
>  #include "monitor.h"
> -#include "buffered_file.h"
> +#include "qemu-file.h"
>  #include "sysemu.h"
>  #include "block.h"
>  #include "qemu_socket.h"
> @@ -569,3 +569,219 @@ int64_t migrate_xbzrle_cache_size(void)
> 
>      return s->xbzrle_cache_size;
>  }
> +
> +/* migration thread support */
> +
> +typedef struct QEMUFileBuffered {
> +    MigrationState *migration_state;
> +    QEMUFile *file;
> +    size_t bytes_xfer;
> +    size_t xfer_limit;
> +    uint8_t *buffer;
> +    size_t buffer_size;
> +    size_t buffer_capacity;
> +    QemuThread thread;
> +} QEMUFileBuffered;
> +
> +static ssize_t buffered_flush(QEMUFileBuffered *s)
> +{
> +    size_t offset = 0;
> +    ssize_t ret = 0;
> +
> +    DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
> +
> +    while (s->bytes_xfer < s->xfer_limit && offset < s->buffer_size) {
> +
> +        ret = migrate_fd_put_buffer(s->migration_state, s->buffer + offset,
> +                                    s->buffer_size - offset);
> +        if (ret <= 0) {
> +            DPRINTF("error flushing data, %zd\n", ret);
> +            break;
> +        } else {
> +            DPRINTF("flushed %zd byte(s)\n", ret);
> +            offset += ret;
> +            s->bytes_xfer += ret;
> +        }
> +    }
> +
> +    DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
> +    memmove(s->buffer, s->buffer + offset, s->buffer_size - offset);
> +    s->buffer_size -= offset;
> +
> +    if (ret < 0) {
> +        return ret;
> +    }
> +    return offset;
> +}
> +
> +static int buffered_put_buffer(void *opaque, const uint8_t *buf,
> +                               int64_t pos, int size)
> +{
> +    QEMUFileBuffered *s = opaque;
> +    ssize_t error;
> +
> +    DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos);
> +
> +    error = qemu_file_get_error(s->file);
> +    if (error) {
> +        DPRINTF("flush when error, bailing: %s\n", strerror(-error));
> +        return error;
> +    }
> +
> +    if (size <= 0) {
> +        return size;
> +    }
> +
> +    if (size > (s->buffer_capacity - s->buffer_size)) {
> +        DPRINTF("increasing buffer capacity from %zu by %zu\n",
> +                s->buffer_capacity, size + 1024);
> +
> +        s->buffer_capacity += size + 1024;
> +
> +        s->buffer = g_realloc(s->buffer, s->buffer_capacity);
> +    }
> +
> +    memcpy(s->buffer + s->buffer_size, buf, size);
> +    s->buffer_size += size;
> +
> +    return size;
> +}
> +
> +static int buffered_close(void *opaque)
> +{
> +    QEMUFileBuffered *s = opaque;
> +    ssize_t ret = 0;
> +    int ret2;
> +
> +    DPRINTF("closing\n");
> +
> +    s->xfer_limit = INT_MAX;
> +    while (!qemu_file_get_error(s->file) && s->buffer_size) {
> +        ret = buffered_flush(s);
> +        if (ret < 0) {
> +            break;
> +        }
> +    }
> +
> +    ret2 = migrate_fd_close(s->migration_state);
> +    if (ret >= 0) {
> +        ret = ret2;
> +    }
> +    ret = migrate_fd_close(s->migration_state);
> +    s->migration_state->complete = true;
> +    return ret;
> +}
> +
> +/*
> + * The meaning of the return values is:
> + *   0: We can continue sending
> + *   1: Time to stop
> + *   negative: There has been an error
> + */
> +static int buffered_rate_limit(void *opaque)
> +{
> +    QEMUFileBuffered *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 buffered_set_rate_limit(void *opaque, int64_t new_rate)
> +{
> +    QEMUFileBuffered *s = opaque;
> +    if (qemu_file_get_error(s->file)) {
> +        goto out;
> +    }
> +    if (new_rate > SIZE_MAX) {
> +        new_rate = SIZE_MAX;
> +    }
> +
> +    s->xfer_limit = new_rate / 10;
> +
> +out:
> +    return s->xfer_limit;
> +}
> +
> +static int64_t buffered_get_rate_limit(void *opaque)
> +{
> +    QEMUFileBuffered *s = opaque;
> +
> +    return s->xfer_limit;
> +}
> +
> +/* 100ms  xfer_limit is the limit that we should write each 100ms */
> +#define BUFFER_DELAY 100
> +
> +static void *buffered_file_thread(void *opaque)
> +{
> +    QEMUFileBuffered *s = opaque;
> +    int64_t initial_time = qemu_get_clock_ms(rt_clock);
> +    int64_t max_size = 0;
> +    bool last_round = false;
> +
> +    while (true) {
> +        int64_t current_time = qemu_get_clock_ms(rt_clock);
> +
> +        if (s->migration_state->complete) {
> +            break;
> +        }
> +        if (current_time >= initial_time + BUFFER_DELAY) {
> +            uint64_t transferred_bytes = s->bytes_xfer;
> +            uint64_t time_spent = current_time - initial_time;
> +            double bandwidth = transferred_bytes / time_spent;
> +            max_size = bandwidth * migrate_max_downtime() / 1000000;
> +
> +            DPRINTF("transferred %" PRIu64 " time_spent %" PRIu64
> +                    " bandwidth %g max_size %" PRId64 "\n",
> +                    transferred_bytes, time_spent, bandwidth, max_size);
> +
> +            s->bytes_xfer = 0;
> +            initial_time = current_time;
> +        }
> +        if (!last_round && (s->bytes_xfer >= s->xfer_limit)) {
> +            /* usleep expects microseconds */
> +            usleep((initial_time + BUFFER_DELAY - current_time)*1000);
> +        }
> +        buffered_flush(s);
> +
> +        DPRINTF("file is ready\n");
> +        if (s->bytes_xfer < s->xfer_limit) {
> +            DPRINTF("notifying client\n");
> +            last_round = migrate_fd_put_ready(s->migration_state, max_size);
> +        }
> +    }
> +
> +    g_free(s->buffer);
> +    g_free(s);
> +    return NULL;
> +}
> +
> +void qemu_fopen_ops_buffered(MigrationState *migration_state)
> +{
> +    QEMUFileBuffered *s;
> +
> +    s = g_malloc0(sizeof(*s));
> +
> +    s->migration_state = migration_state;
> +    s->xfer_limit = migration_state->bandwidth_limit / 10;
> +    s->migration_state->complete = false;
> +
> +    s->file = qemu_fopen_ops(s, buffered_put_buffer, NULL,
> +                             buffered_close, buffered_rate_limit,
> +                             buffered_set_rate_limit,
> +                             buffered_get_rate_limit);
> +
> +    migration_state->file = s->file;
> +
> +    qemu_thread_create(&s->thread, buffered_file_thread, s,
> +                       QEMU_THREAD_DETACHED);
> +}
> diff --git a/migration.h b/migration.h
> index 1f2baed..40c8e9c 100644
> --- a/migration.h
> +++ b/migration.h
> @@ -129,4 +129,5 @@ int64_t migrate_xbzrle_cache_size(void);
> 
>  int64_t xbzrle_cache_resize(int64_t new_size);
> 
> +void qemu_fopen_ops_buffered(MigrationState *migration_state);
>  #endif
>