[Qemu-devel] [PATCH 0/2] memory: Eliminate qemu_ram_free_from_ptr() & memory_region_destructor_ram_from_ptr()

[Qemu-devel] [PATCH 0/2] memory: Eliminate qemu_ram_free_from_ptr() & memory_region_destructor_ram_from_ptr()

[Eduardo Habkost]

This series eliminates two functions that are not needed anymore:
qemu_ram_free_from_ptr(), and memory_region_destructor_ram_from_ptr().

Eduardo Habkost (2):
  exec: Eliminate qemu_ram_free_from_ptr()
  memory: Eliminate memory_region_destructor_ram_from_ptr()

 exec.c                  | 19 -------------------
 include/exec/ram_addr.h |  1 -
 memory.c                |  7 +------
 3 files changed, 1 insertion(+), 26 deletions(-)

-- 
2.1.0

[Qemu-devel] [PATCH 1/2] exec: Eliminate qemu_ram_free_from_ptr()

[Eduardo Habkost]

Replace qemu_ram_free_from_ptr() with qemu_ram_free().

The only difference between qemu_ram_free_from_ptr() and
qemu_ram_free() is that g_free_rcu() is used instead of
call_rcu(reclaim_ramblock). We can safely replace it because:

* RAM blocks allocated by qemu_ram_alloc_from_ptr() always have
  RAM_PREALLOC set;
* reclaim_ramblock(block) will do nothing except g_free(block)
  if RAM_PREALLOC is set at block->flags.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 exec.c                  | 19 -------------------
 include/exec/ram_addr.h |  1 -
 memory.c                |  2 +-
 3 files changed, 1 insertion(+), 21 deletions(-)

diff --git a/exec.c b/exec.c
index a028961..851959b 100644
--- a/exec.c
+++ b/exec.c
@@ -1672,25 +1672,6 @@ ram_addr_t qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t maxsz,
     return qemu_ram_alloc_internal(size, maxsz, resized, NULL, true, mr, errp);
 }
 
-void qemu_ram_free_from_ptr(ram_addr_t addr)
-{
-    RAMBlock *block;
-
-    qemu_mutex_lock_ramlist();
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
-        if (addr == block->offset) {
-            QLIST_REMOVE_RCU(block, next);
-            ram_list.mru_block = NULL;
-            /* Write list before version */
-            smp_wmb();
-            ram_list.version++;
-            g_free_rcu(block, rcu);
-            break;
-        }
-    }
-    qemu_mutex_unlock_ramlist();
-}
-
 static void reclaim_ramblock(RAMBlock *block)
 {
     if (block->flags & RAM_PREALLOC) {
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 3360ac5..b0d3c10 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -77,7 +77,6 @@ int qemu_get_ram_fd(ram_addr_t addr);
 void *qemu_get_ram_block_host_ptr(ram_addr_t addr);
 void *qemu_get_ram_ptr(ram_addr_t addr);
 void qemu_ram_free(ram_addr_t addr);
-void qemu_ram_free_from_ptr(ram_addr_t addr);
 
 int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp);
 
diff --git a/memory.c b/memory.c
index c435c88..183eca5 100644
--- a/memory.c
+++ b/memory.c
@@ -861,7 +861,7 @@ static void memory_region_destructor_ram(MemoryRegion *mr)
 
 static void memory_region_destructor_ram_from_ptr(MemoryRegion *mr)
 {
-    qemu_ram_free_from_ptr(mr->ram_addr);
+    qemu_ram_free(mr->ram_addr);
 }
 
 static void memory_region_destructor_rom_device(MemoryRegion *mr)
-- 
2.1.0

[Qemu-devel] [PATCH 2/2] memory: Eliminate memory_region_destructor_ram_from_ptr()

[Eduardo Habkost]

The function is equivalent to memory_region_destructor_ram(), so
it's not needed anymore.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
 memory.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/memory.c b/memory.c
index 183eca5..57d7d33 100644
--- a/memory.c
+++ b/memory.c
@@ -859,11 +859,6 @@ static void memory_region_destructor_ram(MemoryRegion *mr)
     qemu_ram_free(mr->ram_addr);
 }
 
-static void memory_region_destructor_ram_from_ptr(MemoryRegion *mr)
-{
-    qemu_ram_free(mr->ram_addr);
-}
-
 static void memory_region_destructor_rom_device(MemoryRegion *mr)
 {
     qemu_ram_free(mr->ram_addr & TARGET_PAGE_MASK);
@@ -1246,7 +1241,7 @@ void memory_region_init_ram_ptr(MemoryRegion *mr,
     memory_region_init(mr, owner, name, size);
     mr->ram = true;
     mr->terminates = true;
-    mr->destructor = memory_region_destructor_ram_from_ptr;
+    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.  */
-- 
2.1.0

Re: [Qemu-devel] [PATCH 0/2] memory: Eliminate qemu_ram_free_from_ptr() & memory_region_destructor_ram_from_ptr()

[Paolo Bonzini]

On 06/11/2015 22:20, Eduardo Habkost wrote:
> This series eliminates two functions that are not needed anymore:
> qemu_ram_free_from_ptr(), and memory_region_destructor_ram_from_ptr().
> 
> Eduardo Habkost (2):
>   exec: Eliminate qemu_ram_free_from_ptr()
>   memory: Eliminate memory_region_destructor_ram_from_ptr()
> 
>  exec.c                  | 19 -------------------
>  include/exec/ram_addr.h |  1 -
>  memory.c                |  7 +------
>  3 files changed, 1 insertion(+), 26 deletions(-)
> 

Queued for 2.6, thanks.

Paolo