On Wed, 2 Dec 2020 03:18:52 -0500
Paolo Bonzini <pbonz...@redhat.com> wrote:
> Compute the DIRTY_MEMORY_CODE bit in memory_region_get_dirty_log_mask
> instead of memory_region_init_*. This makes it possible to allocate
> memory backend objects at any time.
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> softmmu/memory.c | 12 ++++++------
> softmmu/vl.c | 6 +-----
> 2 files changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/softmmu/memory.c b/softmmu/memory.c
> index 11ca94d037..89a4723fe5 100644
> --- a/softmmu/memory.c
> +++ b/softmmu/memory.c
> @@ -1548,7 +1548,6 @@ void
> memory_region_init_ram_shared_nomigrate(MemoryRegion *mr,
> mr->terminates = true;
> mr->destructor = memory_region_destructor_ram;
> mr->ram_block = qemu_ram_alloc(size, share, mr, &err);
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
> if (err) {
> mr->size = int128_zero();
> object_unparent(OBJECT(mr));
> @@ -1573,7 +1572,6 @@ void memory_region_init_resizeable_ram(MemoryRegion *mr,
> mr->destructor = memory_region_destructor_ram;
> mr->ram_block = qemu_ram_alloc_resizeable(size, max_size, resized,
> mr, &err);
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
> if (err) {
> mr->size = int128_zero();
> object_unparent(OBJECT(mr));
> @@ -1598,7 +1596,6 @@ void memory_region_init_ram_from_file(MemoryRegion *mr,
> mr->destructor = memory_region_destructor_ram;
> mr->align = align;
> mr->ram_block = qemu_ram_alloc_from_file(size, mr, ram_flags, path,
> &err);
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
> if (err) {
> mr->size = int128_zero();
> object_unparent(OBJECT(mr));
> @@ -1622,7 +1619,6 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr,
> mr->ram_block = qemu_ram_alloc_from_fd(size, mr,
> share ? RAM_SHARED : 0,
> fd, &err);
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
> if (err) {
> mr->size = int128_zero();
> object_unparent(OBJECT(mr));
> @@ -1641,7 +1637,6 @@ void memory_region_init_ram_ptr(MemoryRegion *mr,
> mr->ram = true;
> mr->terminates = true;
> mr->destructor = memory_region_destructor_ram;
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
>
> /* qemu_ram_alloc_from_ptr cannot fail with ptr != NULL. */
> assert(ptr != NULL);
> @@ -1661,7 +1656,7 @@ void memory_region_init_ram_device_ptr(MemoryRegion *mr,
> mr->ops = &ram_device_mem_ops;
> mr->opaque = mr;
> mr->destructor = memory_region_destructor_ram;
> - mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
> +
> /* qemu_ram_alloc_from_ptr cannot fail with ptr != NULL. */
> assert(ptr != NULL);
> mr->ram_block = qemu_ram_alloc_from_ptr(size, ptr, mr, &error_fatal);
> @@ -1819,6 +1814,11 @@ uint8_t memory_region_get_dirty_log_mask(MemoryRegion
> *mr)
> memory_region_is_iommu(mr))) {
> mask |= (1 << DIRTY_MEMORY_MIGRATION);
> }
> +
> + if (tcg_enabled() && rb) {
> + /* TCG only cares about dirty memory logging for RAM, not IOMMU. */
> + mask |= (1 << DIRTY_MEMORY_CODE);
> + }
> return mask;
> }
Is following also necessary?:
diff --git a/softmmu/memory.c b/softmmu/memory.c
index 11ca94d037..f1de42e50f 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -2033,7 +2033,8 @@ void memory_region_set_log(MemoryRegion *mr, bool log,
unsigned client)
}
memory_region_transaction_begin();
- mr->dirty_log_mask = (mr->dirty_log_mask & ~mask) | (log * mask);
+ mr->dirty_log_mask = (memory_region_get_dirty_log_mask(mr) & ~mask) |
+ (log * mask);
memory_region_update_pending |= mr->enabled;
memory_region_transaction_commit();
}
>
> diff --git a/softmmu/vl.c b/softmmu/vl.c
> index 0f63d80472..023c16245b 100644
> --- a/softmmu/vl.c
> +++ b/softmmu/vl.c
> @@ -1715,11 +1715,7 @@ static bool object_create_early(const char *type,
> QemuOpts *opts)
> return false;
> }
>
> - /* Memory allocation by backends needs to be done
> - * after configure_accelerator() (due to the tcg_enabled()
> - * checks at memory_region_init_*()).
> - *
> - * Also, allocation of large amounts of memory may delay
> + /* Allocation of large amounts of memory may delay
> * chardev initialization for too long, and trigger timeouts
> * on software that waits for a monitor socket to be created
> * (e.g. libvirt).
