On 27.05.25 07:47, Chenyi Qiang wrote:
On 5/26/2025 5:08 PM, David Hildenbrand wrote:
On 20.05.25 12:28, Chenyi Qiang wrote:
As guest_memfd is now managed by RamBlockAttribute with
RamDiscardManager, only block uncoordinated discard.
Signed-off-by: Chenyi Qiang <chenyi.qi...@intel.com>
---
Changes in v5:
- Revert to use RamDiscardManager.
Changes in v4:
- Modify commit message (RamDiscardManager->PrivateSharedManager).
Changes in v3:
- No change.
Changes in v2:
- Change the ram_block_discard_require(false) to
ram_block_coordinated_discard_require(false).
---
system/physmem.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/system/physmem.c b/system/physmem.c
index f05f7ff09a..58b7614660 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -1916,7 +1916,7 @@ static void ram_block_add(RAMBlock *new_block,
Error **errp)
}
assert(new_block->guest_memfd < 0);
- ret = ram_block_discard_require(true);
+ ret = ram_block_coordinated_discard_require(true);
if (ret < 0) {
error_setg_errno(errp, -ret,
"cannot set up private guest memory:
discard currently blocked");
@@ -1939,7 +1939,7 @@ static void ram_block_add(RAMBlock *new_block,
Error **errp)
* ever develops a need to check for errors.
*/
close(new_block->guest_memfd);
- ram_block_discard_require(false);
+ ram_block_coordinated_discard_require(false);
qemu_mutex_unlock_ramlist();
goto out_free;
}
@@ -2302,7 +2302,7 @@ static void reclaim_ramblock(RAMBlock *block)
if (block->guest_memfd >= 0) {
ram_block_attribute_destroy(block->ram_shared);
close(block->guest_memfd);
- ram_block_discard_require(false);
+ ram_block_coordinated_discard_require(false);
}
g_free(block);
I think this patch should be squashed into the previous one, then the
story in that single patch is consistent.
I think this patch is a gate to allow device assignment with guest_memfd
and want to make it separately. Can we instead add some commit message
in previous one? like:
"Using guest_memfd with vfio is still blocked via
ram_block_discard_disable()/ram_block_discard_require()."
For the title it should probably be something like:
"physmem: support coordinated discarding of RAM with guest_memdfd"
Then explain how we install the RAMDiscardManager that will notify
listeners (esp. vfio).
--
Cheers,
David / dhildenb
