Re: [PATCH v3 05/13] migration/rdma: Unfold hook_ram_load()

[Zhijian Li (Fujitsu)]

On 12/10/2023 04:35, Juan Quintela wrote:
> There is only one flag called with: RAM_CONTROL_BLOCK_REG.
> 
> Reviewed-by: Peter Xu <peterx@redhat.com>
> Signed-off-by: Juan Quintela <quintela@redhat.com>

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

> ---
>   migration/qemu-file.h | 11 -----------
>   migration/rdma.h      |  3 +++
>   migration/qemu-file.c | 10 ----------
>   migration/ram.c       |  6 ++++--
>   migration/rdma.c      | 34 +++++++++++-----------------------
>   5 files changed, 18 insertions(+), 46 deletions(-)
> 
> diff --git a/migration/qemu-file.h b/migration/qemu-file.h
> index 14ff0d9cc4..80c30631dc 100644
> --- a/migration/qemu-file.h
> +++ b/migration/qemu-file.h
> @@ -29,20 +29,12 @@
>   #include "exec/cpu-common.h"
>   #include "io/channel.h"
>   
> -/*
> - * This function provides hooks around different
> - * stages of RAM migration.
> - * 'data' is call specific data associated with the 'flags' value
> - */
> -typedef int (QEMURamHookFunc)(QEMUFile *f, uint64_t flags, void *data);
> -
>   /*
>    * Constants used by ram_control_* hooks
>    */
>   #define RAM_CONTROL_SETUP     0
>   #define RAM_CONTROL_ROUND     1
>   #define RAM_CONTROL_FINISH    3
> -#define RAM_CONTROL_BLOCK_REG 4
>   
>   /*
>    * This function allows override of where the RAM page
> @@ -54,7 +46,6 @@ typedef int (QEMURamSaveFunc)(QEMUFile *f,
>                                 size_t size);
>   
>   typedef struct QEMUFileHooks {
> -    QEMURamHookFunc *hook_ram_load;
>       QEMURamSaveFunc *save_page;
>   } QEMUFileHooks;
>   
> @@ -124,8 +115,6 @@ 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_load_hook(QEMUFile *f, uint64_t flags, void *data);
> -
>   /* Whenever this is found in the data stream, the flags
>    * will be passed to ram_control_load_hook in the incoming-migration
>    * side. This lets before_ram_iterate/after_ram_iterate add
> diff --git a/migration/rdma.h b/migration/rdma.h
> index 8bd277efb9..8df8b4089a 100644
> --- a/migration/rdma.h
> +++ b/migration/rdma.h
> @@ -27,6 +27,7 @@ void rdma_start_incoming_migration(const char *host_port, 
> Error **errp);
>   int qemu_rdma_registration_handle(QEMUFile *f);
>   int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags);
>   int qemu_rdma_registration_stop(QEMUFile *f, uint64_t flags);
> +int rdma_block_notification_handle(QEMUFile *f, const char *name);
>   #else
>   static inline
>   int qemu_rdma_registration_handle(QEMUFile *f) { return 0; }
> @@ -34,5 +35,7 @@ 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; }
> +static inline
> +int rdma_block_notification_handle(QEMUFile *f, const char *name) { return 
> 0; }
>   #endif
>   #endif
> diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> index e7dba2a849..4a414b8976 100644
> --- a/migration/qemu-file.c
> +++ b/migration/qemu-file.c
> @@ -298,16 +298,6 @@ void qemu_fflush(QEMUFile *f)
>       f->iovcnt = 0;
>   }
>   
> -void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
> -{
> -    if (f->hooks && f->hooks->hook_ram_load) {
> -        int ret = f->hooks->hook_ram_load(f, flags, data);
> -        if (ret < 0) {
> -            qemu_file_set_error(f, ret);
> -        }
> -    }
> -}
> -
>   int ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
>                             ram_addr_t offset, size_t size)
>   {
> diff --git a/migration/ram.c b/migration/ram.c
> index ee8bdcdc82..d6a9f90b94 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -4023,8 +4023,10 @@ static int ram_load_precopy(QEMUFile *f)
>                               ret = -EINVAL;
>                           }
>                       }
> -                    ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG,
> -                                          block->idstr);
> +                    ret = rdma_block_notification_handle(f, block->idstr);
> +                    if (ret < 0) {
> +                        qemu_file_set_error(f, ret);
> +                    }
>                   } else {
>                       error_report("Unknown ramblock \"%s\", cannot "
>                                    "accept migration", id);
> diff --git a/migration/rdma.c b/migration/rdma.c
> index e533814599..6bca9e8f19 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -3799,22 +3799,23 @@ err:
>   }
>   
>   /* Destination:
> - * Called via a ram_control_load_hook during the initial RAM load section 
> which
> - * lists the RAMBlocks by name.  This lets us know the order of the RAMBlocks
> - * on the source.
> - * We've already built our local RAMBlock list, but not yet sent the list to
> - * the source.
> + * Called during the initial RAM load section which lists the
> + * RAMBlocks by name.  This lets us know the order of the RAMBlocks on
> + * the source.  We've already built our local RAMBlock list, but not
> + * yet sent the list to the source.
>    */
> -static int
> -rdma_block_notification_handle(QEMUFile *f, const char *name)
> +int rdma_block_notification_handle(QEMUFile *f, const char *name)
>   {
> -    RDMAContext *rdma;
> -    QIOChannelRDMA *rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
>       int curr;
>       int found = -1;
>   
> +    if (!migrate_rdma()) {
> +        return 0;
> +    }
> +
>       RCU_READ_LOCK_GUARD();
> -    rdma = qatomic_rcu_read(&rioc->rdmain);
> +    QIOChannelRDMA *rioc = QIO_CHANNEL_RDMA(qemu_file_get_ioc(f));
> +    RDMAContext *rdma = qatomic_rcu_read(&rioc->rdmain);
>   
>       if (!rdma) {
>           return -1;
> @@ -3840,18 +3841,6 @@ rdma_block_notification_handle(QEMUFile *f, const char 
> *name)
>       return 0;
>   }
>   
> -static int rdma_load_hook(QEMUFile *f, uint64_t flags, void *data)
> -{
> -    switch (flags) {
> -    case RAM_CONTROL_BLOCK_REG:
> -        return rdma_block_notification_handle(f, data);
> -
> -    default:
> -        /* Shouldn't be called with any other values */
> -        abort();
> -    }
> -}
> -
>   int qemu_rdma_registration_start(QEMUFile *f, uint64_t flags)
>   {
>       if (!migrate_rdma () || migration_in_postcopy()) {
> @@ -3997,7 +3986,6 @@ err:
>   }
>   
>   static const QEMUFileHooks rdma_read_hooks = {
> -    .hook_ram_load = rdma_load_hook,
>   };
>   
>   static const QEMUFileHooks rdma_write_hooks = {