Re: [Qemu-devel] [RFC PATCH RDMA support v3: 09/10] Move RAMBlock to cpu-common.h

[Paolo Bonzini <pbonzini@redhat.com>]

Il 11/03/2013 05:33, Michael.R.Hines.mrhines@linux.vnet.ibm.com ha scritto:
> From: "Michael R. Hines" <mrhines@us.ibm.com>
> 
> RDMA needs access to this structure by including cpu-common.h
> (Including cpu-all.h causes things to throw up on me).
> 
> Signed-off-by: Michael R. Hines <mrhines@us.ibm.com>
> ---
>  include/exec/cpu-all.h    |   27 ---------------------------
>  include/exec/cpu-common.h |   29 +++++++++++++++++++++++++++++
>  2 files changed, 29 insertions(+), 27 deletions(-)
> 
> diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
> index 249e046..02a2808 100644
> --- a/include/exec/cpu-all.h
> +++ b/include/exec/cpu-all.h
> @@ -480,33 +480,6 @@ extern ram_addr_t ram_size;
>  /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */
>  #define RAM_PREALLOC_MASK   (1 << 0)
>  
> -typedef struct RAMBlock {
> -    struct MemoryRegion *mr;
> -    uint8_t *host;
> -    ram_addr_t offset;
> -    ram_addr_t length;
> -    uint32_t flags;
> -    char idstr[256];
> -    /* Reads can take either the iothread or the ramlist lock.
> -     * Writes must take both locks.
> -     */
> -    QTAILQ_ENTRY(RAMBlock) next;
> -#if defined(__linux__) && !defined(TARGET_S390X)
> -    int fd;
> -#endif
> -} RAMBlock;
> -
> -typedef struct RAMList {
> -    QemuMutex mutex;
> -    /* Protected by the iothread lock.  */
> -    uint8_t *phys_dirty;
> -    RAMBlock *mru_block;
> -    /* Protected by the ramlist lock.  */
> -    QTAILQ_HEAD(, RAMBlock) blocks;
> -    uint32_t version;
> -} RAMList;
> -extern RAMList ram_list;
> -
>  extern const char *mem_path;
>  extern int mem_prealloc;
>  
> diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
> index 2e5f11f..763cef3 100644
> --- a/include/exec/cpu-common.h
> +++ b/include/exec/cpu-common.h
> @@ -11,6 +11,7 @@
>  
>  #include "qemu/bswap.h"
>  #include "qemu/queue.h"
> +#include "qemu/thread.h"
>  
>  /**
>   * CPUListState:
> @@ -121,4 +122,32 @@ extern struct MemoryRegion io_mem_notdirty;
>  
>  #endif
>  
> +typedef struct RAMBlock {
> +    struct MemoryRegion *mr;
> +    uint8_t *host;
> +    ram_addr_t offset;
> +    ram_addr_t length;
> +    uint32_t flags;
> +    char idstr[256];
> +    /* Reads can take either the iothread or the ramlist lock.
> +     * Writes must take both locks.
> +     */
> +    QTAILQ_ENTRY(RAMBlock) next;
> +#if defined(__linux__) && !defined(TARGET_S390X)
> +    int fd;
> +#endif
> +} RAMBlock;
> +
> +typedef struct RAMList {
> +    QemuMutex mutex;
> +    /* Protected by the iothread lock.  */
> +    uint8_t *phys_dirty;
> +    RAMBlock *mru_block;
> +    /* Protected by the ramlist lock.  */
> +    QTAILQ_HEAD(, RAMBlock) blocks;
> +    uint32_t version;
> +} RAMList;
> +
> +extern RAMList ram_list;
> +
>  #endif /* !CPU_COMMON_H */
> 

Only used in qemu_rdma_init_ram_blocks.  Can you add instead an API like

qemu_ram_foreach_block(
  void (*fn)(void *host_addr, ram_addr_t offset, ram_addr_t length,
             void *opaque),
  void *opaque)

?

BTW, please avoid arbitrary limits like RDMA_MAX_RAM_BLOCKS.  Can you
use a list (see qemu-queue.h; it is the same as the BSD queue.h) instead
of current_index?

Paolo