Re: [Qemu-devel] [PATCH 17/38] memory: split dirty bitmap into three

[Orit Wasserman <owasserm@redhat.com>]

On 12/17/2013 05:25 PM, Juan Quintela wrote:
> After all the previous patches, spliting the bitmap gets direct.
>
> Note: For some reason, I have to move DIRTY_MEMORY_* definitions to
> the beginning of memory.h to make compilation work.
>
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> ---
>   exec.c                         |  9 ++++++---
>   include/exec/cpu-all.h         |  3 ++-
>   include/exec/memory-internal.h |  9 +++------
>   include/exec/memory.h          | 10 +++++-----
>   4 files changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index bed5c07..ad9866c 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1276,9 +1276,12 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
>       new_ram_size = last_ram_offset() >> TARGET_PAGE_BITS;
>
>       if (new_ram_size > old_ram_size) {
> -        ram_list.phys_dirty = g_realloc(ram_list.phys_dirty, new_ram_size);
> -        memset(ram_list.phys_dirty + (new_block->offset >> TARGET_PAGE_BITS),
> -           0, size >> TARGET_PAGE_BITS);
> +        int i;
> +        for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
> +            ram_list.dirty_memory[i] =
> +                bitmap_zero_extend(ram_list.dirty_memory[i],
> +                                   old_ram_size, new_ram_size);
> +       }
>       }
>       cpu_physical_memory_set_dirty_range(new_block->offset, size);
>
> diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
> index b6998f0..4cb4b4a 100644
> --- a/include/exec/cpu-all.h
> +++ b/include/exec/cpu-all.h
> @@ -21,6 +21,7 @@
>
>   #include "qemu-common.h"
>   #include "exec/cpu-common.h"
> +#include "exec/memory.h"
>   #include "qemu/thread.h"
>   #include "qom/cpu.h"
>
> @@ -459,7 +460,7 @@ typedef struct RAMBlock {
>   typedef struct RAMList {
>       QemuMutex mutex;
>       /* Protected by the iothread lock.  */
> -    uint8_t *phys_dirty;
> +    unsigned long *dirty_memory[DIRTY_MEMORY_NUM];
>       RAMBlock *mru_block;
>       /* Protected by the ramlist lock.  */
>       QTAILQ_HEAD(, RAMBlock) blocks;
> diff --git a/include/exec/memory-internal.h b/include/exec/memory-internal.h
> index 666490c..6fb1b64 100644
> --- a/include/exec/memory-internal.h
> +++ b/include/exec/memory-internal.h
> @@ -44,7 +44,7 @@ static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
>                                                         unsigned client)
>   {
>       assert(client < DIRTY_MEMORY_NUM);
> -    return ram_list.phys_dirty[addr >> TARGET_PAGE_BITS] & (1 << client);
> +    return test_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
>   }
>
>   /* read dirty bit (return 0 or 1) */
> @@ -76,7 +76,7 @@ static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
>                                                         unsigned client)
>   {
>       assert(client < DIRTY_MEMORY_NUM);
> -    ram_list.phys_dirty[addr >> TARGET_PAGE_BITS] |= (1 << client);
> +    set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
>   }
>
>   static inline void cpu_physical_memory_set_dirty(ram_addr_t addr)
> @@ -89,11 +89,8 @@ static inline void cpu_physical_memory_set_dirty(ram_addr_t addr)
>   static inline void cpu_physical_memory_clear_dirty_flag(ram_addr_t addr,
>                                                          unsigned client)
>   {
> -    int mask = ~(1 << client);
> -
>       assert(client < DIRTY_MEMORY_NUM);
> -
> -    ram_list.phys_dirty[addr >> TARGET_PAGE_BITS] &= mask;
> +    clear_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
>   }
>
>   static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index d5e9d58..296d6ab 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -16,6 +16,11 @@
>
>   #ifndef CONFIG_USER_ONLY
>
> +#define DIRTY_MEMORY_VGA       0
> +#define DIRTY_MEMORY_CODE      1
> +#define DIRTY_MEMORY_MIGRATION 2
> +#define DIRTY_MEMORY_NUM       3        /* num of dirty bits */
> +
>   #include <stdint.h>
>   #include <stdbool.h>
>   #include "qemu-common.h"
> @@ -33,11 +38,6 @@
>   typedef struct MemoryRegionOps MemoryRegionOps;
>   typedef struct MemoryRegionMmio MemoryRegionMmio;
>
> -#define DIRTY_MEMORY_VGA       0
> -#define DIRTY_MEMORY_CODE      1
> -#define DIRTY_MEMORY_MIGRATION 2
> -#define DIRTY_MEMORY_NUM       3        /* num of dirty bits */
> -
>   struct MemoryRegionMmio {
>       CPUReadMemoryFunc *read[3];
>       CPUWriteMemoryFunc *write[3];
>

Reviewed-by: Orit Wasserman <owasserm@redhat.com>