Re: [Qemu-devel] [PATCH 08/15] memory: introduce PhysMap to present snapshot of toploygy

[Blue Swirl]

On Wed, Aug 8, 2012 at 6:25 AM, Liu Ping Fan <address@hidden> wrote:
> From: Liu Ping Fan <address@hidden>
>
> PhysMap contain the flatview and radix-tree view, they are snapshot
> of system topology and should be consistent. With PhysMap, we can
> swap the pointer when updating and achieve the atomic.
>
> Signed-off-by: Liu Ping Fan <address@hidden>
> ---
>  exec.c   |    8 --------
>  memory.c |   33 ---------------------------------
>  memory.h |   62 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
>  3 files changed, 60 insertions(+), 43 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index 0e29ef9..01b91b0 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -156,8 +156,6 @@ typedef struct PageDesc {
>  #endif
>
>  /* Size of the L2 (and L3, etc) page tables.  */

Please copy this comment to the header file.

> -#define L2_BITS 10
> -#define L2_SIZE (1 << L2_BITS)
>
>  #define P_L2_LEVELS \
>      (((TARGET_PHYS_ADDR_SPACE_BITS - TARGET_PAGE_BITS - 1) / L2_BITS) + 1)
> @@ -185,7 +183,6 @@ uintptr_t qemu_host_page_mask;
>  static void *l1_map[V_L1_SIZE];
>
>  #if !defined(CONFIG_USER_ONLY)
> -typedef struct PhysPageEntry PhysPageEntry;
>
>  static MemoryRegionSection *phys_sections;
>  static unsigned phys_sections_nb, phys_sections_nb_alloc;
> @@ -194,11 +191,6 @@ static uint16_t phys_section_notdirty;
>  static uint16_t phys_section_rom;
>  static uint16_t phys_section_watch;
>
> -struct PhysPageEntry {
> -    uint16_t is_leaf : 1;
> -     /* index into phys_sections (is_leaf) or phys_map_nodes (!is_leaf) */
> -    uint16_t ptr : 15;
> -};
>
>  /* Simple allocator for PhysPageEntry nodes */
>  static PhysPageEntry (*phys_map_nodes)[L2_SIZE];
> diff --git a/memory.c b/memory.c
> index 2eaa2fc..c7f2cfd 100644
> --- a/memory.c
> +++ b/memory.c
> @@ -31,17 +31,6 @@ static bool global_dirty_log = false;
>  static QTAILQ_HEAD(memory_listeners, MemoryListener) memory_listeners
>      = QTAILQ_HEAD_INITIALIZER(memory_listeners);
>
> -typedef struct AddrRange AddrRange;
> -
> -/*
> - * Note using signed integers limits us to physical addresses at most
> - * 63 bits wide.  They are needed for negative offsetting in aliases
> - * (large MemoryRegion::alias_offset).
> - */
> -struct AddrRange {
> -    Int128 start;
> -    Int128 size;
> -};
>
>  static AddrRange addrrange_make(Int128 start, Int128 size)
>  {
> @@ -197,28 +186,6 @@ static bool 
> memory_region_ioeventfd_equal(MemoryRegionIoeventfd a,
>          && !memory_region_ioeventfd_before(b, a);
>  }
>
> -typedef struct FlatRange FlatRange;
> -typedef struct FlatView FlatView;
> -
> -/* Range of memory in the global map.  Addresses are absolute. */
> -struct FlatRange {
> -    MemoryRegion *mr;
> -    target_phys_addr_t offset_in_region;
> -    AddrRange addr;
> -    uint8_t dirty_log_mask;
> -    bool readable;
> -    bool readonly;
> -};
> -
> -/* Flattened global view of current active memory hierarchy.  Kept in sorted
> - * order.
> - */
> -struct FlatView {
> -    FlatRange *ranges;
> -    unsigned nr;
> -    unsigned nr_allocated;
> -};
> -
>  typedef struct AddressSpace AddressSpace;
>  typedef struct AddressSpaceOps AddressSpaceOps;
>
> diff --git a/memory.h b/memory.h
> index 740f018..357edd8 100644
> --- a/memory.h
> +++ b/memory.h
> @@ -29,12 +29,72 @@
>  #include "qemu-thread.h"
>  #include "qemu/reclaimer.h"
>
> +typedef struct AddrRange AddrRange;
> +typedef struct FlatRange FlatRange;
> +typedef struct FlatView FlatView;
> +typedef struct PhysPageEntry PhysPageEntry;
> +typedef struct PhysMap PhysMap;
> +typedef struct MemoryRegionSection MemoryRegionSection;
>  typedef struct MemoryRegionOps MemoryRegionOps;
>  typedef struct MemoryRegionLifeOps MemoryRegionLifeOps;
>  typedef struct MemoryRegion MemoryRegion;
>  typedef struct MemoryRegionPortio MemoryRegionPortio;
>  typedef struct MemoryRegionMmio MemoryRegionMmio;
>
> +/*
> + * Note using signed integers limits us to physical addresses at most
> + * 63 bits wide.  They are needed for negative offsetting in aliases
> + * (large MemoryRegion::alias_offset).
> + */
> +struct AddrRange {
> +    Int128 start;
> +    Int128 size;
> +};
> +
> +/* Range of memory in the global map.  Addresses are absolute. */
> +struct FlatRange {
> +    MemoryRegion *mr;
> +    target_phys_addr_t offset_in_region;
> +    AddrRange addr;
> +    uint8_t dirty_log_mask;
> +    bool readable;
> +    bool readonly;
> +};
> +
> +/* Flattened global view of current active memory hierarchy.  Kept in sorted
> + * order.
> + */
> +struct FlatView {
> +    FlatRange *ranges;
> +    unsigned nr;
> +    unsigned nr_allocated;
> +};
> +
> +struct PhysPageEntry {
> +    uint16_t is_leaf:1;
> +     /* index into phys_sections (is_leaf) or phys_map_nodes (!is_leaf) */
> +    uint16_t ptr:15;
> +};
> +
> +#define L2_BITS 10
> +#define L2_SIZE (1 << L2_BITS)
> +/* This is a multi-level map on the physical address space.
> +   The bottom level has pointers to MemoryRegionSections.  */
> +struct PhysMap {
> +    Atomic ref;
> +    PhysPageEntry root;
> +    PhysPageEntry (*phys_map_nodes)[L2_SIZE];
> +    unsigned phys_map_nodes_nb;
> +    unsigned phys_map_nodes_nb_alloc;
> +
> +    MemoryRegionSection *phys_sections;
> +    unsigned phys_sections_nb;
> +    unsigned phys_sections_nb_alloc;
> +
> +    /* FlatView */
> +    FlatView views[2];
> +};
> +
>  /* Must match *_DIRTY_FLAGS in cpu-all.h.  To be replaced with dynamic
>   * registration.
>   */
> @@ -167,8 +227,6 @@ struct MemoryRegionPortio {
>
>  #define PORTIO_END_OF_LIST() { }
>
> -typedef struct MemoryRegionSection MemoryRegionSection;
> -
>  /**
>   * MemoryRegionSection: describes a fragment of a #MemoryRegion
>   *
> --
> 1.7.4.4
>