Re: [PATCH v3 03/13] migration/rdma: Unfold ram_control_after_iterate()

[Zhijian Li (Fujitsu)]

On 12/10/2023 04:35, Juan Quintela wrote:
> Once there:
> - Remove unused data parameter
> - unfold it in its callers
> - change all callers to call qemu_rdma_registration_stop()
> - We need to call QIO_CHANNEL_RDMA() after we check for migrate_rdma()
> 
> Reviewed-by: Peter Xu <peterx@redhat.com>
> Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>

> 
> ---
> 
> This function has goto's.  So I don't change the place where we
> declare variables, althought I think that it is correct, just don't
> start that discussion.
> ---
>   migration/qemu-file.h |  2 --
>   migration/rdma.h      |  3 +++
>   migration/qemu-file.c | 12 ------------
>   migration/ram.c       | 17 ++++++++++++++---
>   migration/rdma.c      |  9 ++++-----
>   5 files changed, 21 insertions(+), 22 deletions(-)
> 
> diff --git a/migration/qemu-file.h b/migration/qemu-file.h
> index d6a370c569..35e671a01e 100644
> --- a/migration/qemu-file.h
> +++ b/migration/qemu-file.h
> @@ -55,7 +55,6 @@ typedef int (QEMURamSaveFunc)(QEMUFile *f,
>                                 size_t size);
>   
>   typedef struct QEMUFileHooks {
> -    QEMURamHookFunc *after_ram_iterate;
>       QEMURamHookFunc *hook_ram_load;
>       QEMURamSaveFunc *save_page;
>   } QEMUFileHooks;
> @@ -126,7 +125,6 @@ void qemu_fflush(QEMUFile *f);
>   void qemu_file_set_blocking(QEMUFile *f, bool block);
>   int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size);
>   
> -void ram_control_after_iterate(QEMUFile *f, uint64_t flags);
>   void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data);
>   
>   /* Whenever this is found in the data stream, the flags
> diff --git a/migration/rdma.h b/migration/rdma.h
> index 670c67a8cb..c13b94c782 100644
> --- a/migration/rdma.h
> +++ b/migration/rdma.h
> @@ -25,8 +25,11 @@ void rdma_start_incoming_migration(const char *host_port, 
> Error **errp);
>   
>   #ifdef CONFIG_RDMA
>   int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags);
> +int qemu_rdma_registration_stop(QEMUFile *f, uint64_t flags);
>   #else
>   static inline
>   int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags) { return 0; }
> +static inline
> +int qemu_rdma_registration_stop(QEMUFile *f, uint64_t flags) { return 0; }
>   #endif
>   #endif
> diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> index 5e2d73fd68..e7dba2a849 100644
> --- a/migration/qemu-file.c
> +++ b/migration/qemu-file.c
> @@ -298,18 +298,6 @@ void qemu_fflush(QEMUFile *f)
>       f->iovcnt = 0;
>   }
>   
> -void ram_control_after_iterate(QEMUFile *f, uint64_t flags)
> -{
> -    int ret = 0;
> -
> -    if (f->hooks && f->hooks->after_ram_iterate) {
> -        ret = f->hooks->after_ram_iterate(f, flags, NULL);
> -        if (ret < 0) {
> -            qemu_file_set_error(f, ret);
> -        }
> -    }
> -}
> -
>   void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
>   {
>       if (f->hooks && f->hooks->hook_ram_load) {
> diff --git a/migration/ram.c b/migration/ram.c
> index ab590a983f..15bd4ad697 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -3067,7 +3067,11 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
>       if (ret < 0) {
>           qemu_file_set_error(f, ret);
>       }
> -    ram_control_after_iterate(f, RAM_CONTROL_SETUP);
> +
> +    ret = qemu_rdma_registration_stop(f, RAM_CONTROL_SETUP);
> +    if (ret < 0) {
> +        qemu_file_set_error(f, ret);
> +    }
>   
>       migration_ops = g_malloc0(sizeof(MigrationOps));
>       migration_ops->ram_save_target_page = ram_save_target_page_legacy;
> @@ -3186,7 +3190,10 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
>        * Must occur before EOS (or any QEMUFile operation)
>        * because of RDMA protocol.
>        */
> -    ram_control_after_iterate(f, RAM_CONTROL_ROUND);
> +    ret = qemu_rdma_registration_stop(f, RAM_CONTROL_ROUND);
> +    if (ret < 0) {
> +        qemu_file_set_error(f, ret);
> +    }
>   
>   out:
>       if (ret >= 0
> @@ -3259,7 +3266,11 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
>           qemu_mutex_unlock(&rs->bitmap_mutex);
>   
>           ram_flush_compressed_data(rs);
> -        ram_control_after_iterate(f, RAM_CONTROL_FINISH);
> +
> +        int ret = qemu_rdma_registration_stop(f, RAM_CONTROL_FINISH);
> +        if (ret < 0) {
> +            qemu_file_set_error(f, ret);
> +        }
>       }
>   
>       if (ret < 0) {
> diff --git a/migration/rdma.c b/migration/rdma.c
> index a8bfc052c4..99c0914a23 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -3878,20 +3878,20 @@ int qemu_rdma_registration_start(QEMUFile *f, 
> uint64_t flags)
>    * Inform dest that dynamic registrations are done for now.
>    * First, flush writes, if any.
>    */
> -static int qemu_rdma_registration_stop(QEMUFile *f,
> -                                       uint64_t flags, void *data)
> +int qemu_rdma_registration_stop(QEMUFile *f, uint64_t flags)
>   {
> -    QIOChannelRDMA *rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
> +    QIOChannelRDMA *rioc;
>       Error *err = NULL;
>       RDMAContext *rdma;
>       RDMAControlHeader head = { .len = 0, .repeat = 1 };
>       int ret;
>   
> -    if (migration_in_postcopy()) {
> +    if (!migrate_rdma() || migration_in_postcopy()) {
>           return 0;
>       }
>   
>       RCU_READ_LOCK_GUARD();
> +    rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
>       rdma = qatomic_rcu_read(&rioc->rdmaout);
>       if (!rdma) {
>           return -1;
> @@ -3999,7 +3999,6 @@ static const QEMUFileHooks rdma_read_hooks = {
>   };
>   
>   static const QEMUFileHooks rdma_write_hooks = {
> -    .after_ram_iterate  = qemu_rdma_registration_stop,
>       .save_page          = qemu_rdma_save_page,
>   };
>