Re: [PATCH] memory: Have 'info mtree' remove duplicated Address Space information

[Philippe Mathieu-Daudé]

On 8/20/21 12:54 PM, Philippe Mathieu-Daudé wrote:
> Per Peter Maydell [*]:
> 
>   'info mtree' monitor command was designed on the assumption that
>   there's really only one or two interesting address spaces, and
>   with more recent developments that's just not the case any more.
> 
> Similarly about how the FlatView are sorted using a GHashTable,
> sort the AddressSpace objects to remove the duplications (AS
> using the same root MemoryRegion).
> 
> This drastically reduce 'info mtree' on some boards.
> 
> Before:
> 
>   $ (echo info mtree; echo q) \
>     | qemu-system-aarch64 -S -monitor stdio -M raspi3b \
>     | wc -l
>   423
> 
> After:
> 
>   $ (echo info mtree; echo q) \
>     | qemu-system-aarch64 -S -monitor stdio -M raspi3b \
>     | wc -l
>   108
> 
>   (qemu) info mtree
>   address-space: I/O
>     0000000000000000-000000000000ffff (prio 0, i/o): io
> 
>   address-space shared 9 times:
>     - cpu-memory-0
>     - cpu-memory-1
>     - cpu-memory-2
>     - cpu-memory-3
>     - cpu-secure-memory-0
>     - cpu-secure-memory-1
>     - cpu-secure-memory-2
>     - cpu-secure-memory-3
>     - memory
>     0000000000000000-ffffffffffffffff (prio 0, i/o): system
>       0000000000000000-000000003fffffff (prio 0, ram): ram
>       000000003f000000-000000003fffffff (prio 1, i/o): bcm2835-peripherals
>         000000003f003000-000000003f00301f (prio 0, i/o): bcm2835-sys-timer
>         000000003f004000-000000003f004fff (prio -1000, i/o): bcm2835-txp
>         000000003f006000-000000003f006fff (prio 0, i/o): mphi
>         000000003f007000-000000003f007fff (prio 0, i/o): bcm2835-dma
>         000000003f00b200-000000003f00b3ff (prio 0, i/o): bcm2835-ic
>         000000003f00b400-000000003f00b43f (prio -1000, i/o): bcm2835-sp804
>         000000003f00b800-000000003f00bbff (prio 0, i/o): bcm2835-mbox
>         000000003f100000-000000003f1001ff (prio 0, i/o): bcm2835-powermgt
>         000000003f101000-000000003f102fff (prio 0, i/o): bcm2835-cprman
>         000000003f104000-000000003f10400f (prio 0, i/o): bcm2835-rng
>         000000003f200000-000000003f200fff (prio 0, i/o): bcm2835_gpio
>         000000003f201000-000000003f201fff (prio 0, i/o): pl011
>         000000003f202000-000000003f202fff (prio 0, i/o): bcm2835-sdhost
>         000000003f203000-000000003f2030ff (prio -1000, i/o): bcm2835-i2s
>         000000003f204000-000000003f20401f (prio -1000, i/o): bcm2835-spi0
>         000000003f205000-000000003f20501f (prio -1000, i/o): bcm2835-i2c0
>         000000003f20f000-000000003f20f07f (prio -1000, i/o): bcm2835-otp
>         000000003f212000-000000003f212007 (prio 0, i/o): bcm2835-thermal
>         000000003f214000-000000003f2140ff (prio -1000, i/o): bcm2835-spis
>         000000003f215000-000000003f2150ff (prio 0, i/o): bcm2835-aux
>         000000003f300000-000000003f3000ff (prio 0, i/o): sdhci
>         000000003f600000-000000003f6000ff (prio -1000, i/o): bcm2835-smi
>         000000003f804000-000000003f80401f (prio -1000, i/o): bcm2835-i2c1
>         000000003f805000-000000003f80501f (prio -1000, i/o): bcm2835-i2c2
>         000000003f900000-000000003f907fff (prio -1000, i/o): bcm2835-dbus
>         000000003f910000-000000003f917fff (prio -1000, i/o): bcm2835-ave0
>         000000003f980000-000000003f990fff (prio 0, i/o): dwc2
>           000000003f980000-000000003f980fff (prio 0, i/o): dwc2-io
>           000000003f981000-000000003f990fff (prio 0, i/o): dwc2-fifo
>         000000003fc00000-000000003fc00fff (prio -1000, i/o): bcm2835-v3d
>         000000003fe00000-000000003fe000ff (prio -1000, i/o): bcm2835-sdramc
>         000000003fe05000-000000003fe050ff (prio 0, i/o): bcm2835-dma-chan15
>       0000000040000000-00000000400000ff (prio 0, i/o): bcm2836-control
> 
>   address-space shared 4 times:
>     - bcm2835-dma-memory
>     - bcm2835-fb-memory
>     - bcm2835-property-memory
>     - dwc2
>     0000000000000000-00000000ffffffff (prio 0, i/o): bcm2835-gpu
>       0000000000000000-000000003fffffff (prio 0, ram): alias 
> bcm2835-gpu-ram-alias[*] @ram 0000000000000000-000000003fffffff
>       0000000040000000-000000007fffffff (prio 0, ram): alias 
> bcm2835-gpu-ram-alias[*] @ram 0000000000000000-000000003fffffff
>       000000007e000000-000000007effffff (prio 1, i/o): alias 
> bcm2835-peripherals @bcm2835-peripherals 0000000000000000-0000000000ffffff
>       0000000080000000-00000000bfffffff (prio 0, ram): alias 
> bcm2835-gpu-ram-alias[*] @ram 0000000000000000-000000003fffffff
>       00000000c0000000-00000000ffffffff (prio 0, ram): alias 
> bcm2835-gpu-ram-alias[*] @ram 0000000000000000-000000003fffffff
> 
>   address-space: bcm2835-mbox-memory
>     0000000000000000-000000000000008f (prio 0, i/o): bcm2835-mbox
>       0000000000000010-000000000000001f (prio 0, i/o): bcm2835-fb
>       0000000000000080-000000000000008f (prio 0, i/o): bcm2835-property
> 
>   memory-region: ram
>     0000000000000000-000000003fffffff (prio 0, ram): ram
> 
>   memory-region: bcm2835-peripherals
>     000000003f000000-000000003fffffff (prio 1, i/o): bcm2835-peripherals
>       000000003f003000-000000003f00301f (prio 0, i/o): bcm2835-sys-timer
>       000000003f004000-000000003f004fff (prio -1000, i/o): bcm2835-txp
>       000000003f006000-000000003f006fff (prio 0, i/o): mphi
>       000000003f007000-000000003f007fff (prio 0, i/o): bcm2835-dma
>       000000003f00b200-000000003f00b3ff (prio 0, i/o): bcm2835-ic
>       000000003f00b400-000000003f00b43f (prio -1000, i/o): bcm2835-sp804
>       000000003f00b800-000000003f00bbff (prio 0, i/o): bcm2835-mbox
>       000000003f100000-000000003f1001ff (prio 0, i/o): bcm2835-powermgt
>       000000003f101000-000000003f102fff (prio 0, i/o): bcm2835-cprman
>       000000003f104000-000000003f10400f (prio 0, i/o): bcm2835-rng
>       000000003f200000-000000003f200fff (prio 0, i/o): bcm2835_gpio
>       000000003f201000-000000003f201fff (prio 0, i/o): pl011
>       000000003f202000-000000003f202fff (prio 0, i/o): bcm2835-sdhost
>       000000003f203000-000000003f2030ff (prio -1000, i/o): bcm2835-i2s
>       000000003f204000-000000003f20401f (prio -1000, i/o): bcm2835-spi0
>       000000003f205000-000000003f20501f (prio -1000, i/o): bcm2835-i2c0
>       000000003f20f000-000000003f20f07f (prio -1000, i/o): bcm2835-otp
>       000000003f212000-000000003f212007 (prio 0, i/o): bcm2835-thermal
>       000000003f214000-000000003f2140ff (prio -1000, i/o): bcm2835-spis
>       000000003f215000-000000003f2150ff (prio 0, i/o): bcm2835-aux
>       000000003f300000-000000003f3000ff (prio 0, i/o): sdhci
>       000000003f600000-000000003f6000ff (prio -1000, i/o): bcm2835-smi
>       000000003f804000-000000003f80401f (prio -1000, i/o): bcm2835-i2c1
>       000000003f805000-000000003f80501f (prio -1000, i/o): bcm2835-i2c2
>       000000003f900000-000000003f907fff (prio -1000, i/o): bcm2835-dbus
>       000000003f910000-000000003f917fff (prio -1000, i/o): bcm2835-ave0
>       000000003f980000-000000003f990fff (prio 0, i/o): dwc2
>         000000003f980000-000000003f980fff (prio 0, i/o): dwc2-io
>         000000003f981000-000000003f990fff (prio 0, i/o): dwc2-fifo
>       000000003fc00000-000000003fc00fff (prio -1000, i/o): bcm2835-v3d
>       000000003fe00000-000000003fe000ff (prio -1000, i/o): bcm2835-sdramc
>       000000003fe05000-000000003fe050ff (prio 0, i/o): bcm2835-dma-chan15
> 
>   (qemu) q
> 
> [*] https://www.mail-archive.com/qemu-devel@nongnu.org/msg829821.html
> 
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
>  softmmu/memory.c | 73 +++++++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 69 insertions(+), 4 deletions(-)
> 
> diff --git a/softmmu/memory.c b/softmmu/memory.c
> index bfedaf9c4df..0653b06b7cf 100644
> --- a/softmmu/memory.c
> +++ b/softmmu/memory.c
> @@ -3246,11 +3246,64 @@ static gboolean mtree_info_flatview_free(gpointer 
> key, gpointer value,
>      return true;
>  }
>  
> +struct AddressSpaceInfo {
> +    MemoryRegionListHead *ml_head;
> +    int counter;

Doh this field is unused :/

> +    bool owner;
> +    bool disabled;
> +};
> +
> +/* Returns negative value if a < b; zero if a = b; positive value if a > b. 
> */
> +static gint address_space_compare_name(gconstpointer a, gconstpointer b)
> +{
> +    const AddressSpace *as_a = a;
> +    const AddressSpace *as_b = b;
> +
> +    return g_strcmp0(as_a->name, as_b->name);
> +}
> +static void mtree_print_as_name(gpointer data, gpointer user_data)
> +{
> +    AddressSpace *as = data;
> +
> +    qemu_printf("  - %s\n", as->name);
> +}
> +
> +static void mtree_print_as(gpointer key, gpointer value, gpointer user_data)
> +{
> +    MemoryRegion *mr = key;
> +    GSList *as_same_root_mr_list = value;
> +    struct AddressSpaceInfo *asi = user_data;
> +    guint same_root_len = g_slist_length(as_same_root_mr_list);
> +
> +    if (same_root_len == 1) {
> +        AddressSpace *as = g_slist_nth_data(as_same_root_mr_list, 0);
> +
> +        qemu_printf("address-space: %s\n", as->name);
> +    } else {
> +        qemu_printf("address-space shared %u times:\n", same_root_len);
> +        g_slist_foreach(as_same_root_mr_list, mtree_print_as_name, NULL);
> +    }
> +    mtree_print_mr(mr, 1, 0, asi->ml_head, asi->owner, asi->disabled);
> +    qemu_printf("\n");
> +}
> +
> +static gboolean mtree_info_as_free(gpointer key, gpointer value,
> +                                   gpointer user_data)
> +{
> +    GSList *as_same_root_mr_list = value;
> +
> +    g_slist_free(as_same_root_mr_list);
> +
> +    return true;
> +}
> +
>  void mtree_info(bool flatview, bool dispatch_tree, bool owner, bool disabled)
>  {
>      MemoryRegionListHead ml_head;
>      MemoryRegionList *ml, *ml2;
>      AddressSpace *as;
> +    GHashTable *views = g_hash_table_new(g_direct_hash, g_direct_equal);
> +    GSList *as_same_root_mr_list;
>  
>      if (flatview) {
>          FlatView *view;
> @@ -3260,7 +3313,6 @@ void mtree_info(bool flatview, bool dispatch_tree, bool 
> owner, bool disabled)
>              .owner = owner,
>          };
>          GArray *fv_address_spaces;
> -        GHashTable *views = g_hash_table_new(g_direct_hash, g_direct_equal);
>          AccelClass *ac = ACCEL_GET_CLASS(current_accel());
>  
>          if (ac->has_memory) {
> @@ -3293,11 +3345,24 @@ void mtree_info(bool flatview, bool dispatch_tree, 
> bool owner, bool disabled)
>      QTAILQ_INIT(&ml_head);
>  
>      QTAILQ_FOREACH(as, &address_spaces, address_spaces_link) {
> -        qemu_printf("address-space: %s\n", as->name);
> -        mtree_print_mr(as->root, 1, 0, &ml_head, owner, disabled);
> -        qemu_printf("\n");
> +        /* Create hashtable, key=AS root MR, value = list of AS */
> +        as_same_root_mr_list = g_hash_table_lookup(views, as->root);
> +        as_same_root_mr_list = g_slist_insert_sorted(as_same_root_mr_list, 
> as,
> +                                                     
> address_space_compare_name);
> +        g_hash_table_insert(views, as->root, as_same_root_mr_list);
>      }
>  
> +    struct AddressSpaceInfo asi = {
> +        .ml_head = &ml_head,
> +        .owner = owner,
> +        .disabled = disabled,
> +    };
> +
> +    /* print address spaces */
> +    g_hash_table_foreach(views, mtree_print_as, &asi);
> +    g_hash_table_foreach_remove(views, mtree_info_as_free, 0);
> +    g_hash_table_unref(views);
> +
>      /* print aliased regions */
>      QTAILQ_FOREACH(ml, &ml_head, mrqueue) {
>          qemu_printf("memory-region: %s\n", memory_region_name(ml->mr));
>