On 8/18/26 10:07, Yogesh Vyas wrote:
Hi Richard,
On Sun, Aug 16, 2026 at 10:38 PM Yogesh Vyas <[email protected]
<mailto:[email protected]>> wrote:
Hi Richard,
Thank you for improvising on the initial patch shared.
On Thu, Aug 13, 2026 at 6:20 AM Richard Henderson
<[email protected]
<mailto:[email protected]>> wrote:
Hi Yogesh,
The main problem with your patch is where you've placed the change:
tcg_region_initial_alloc__locked is also used by tcg_region_reset_all,
used by tb_flush. Along that path, we really can't have a failure.
The path on which we can defer allocation is via tcg_register_thread.
The second change I made is to use code_buf_ptr == NULL to signal
reallocation is required. In addition, tcg_tb_alloc doesn't need
to immediately fail: in the interim since thread creation, we may
well have performed a tb_flush already.
Please have a try vs your hotplug test case.
I tried testing these patches on my x86 host running qemu-system-ppc64 by
initially
hotpluging 400 vCPUs.
While the response was relatively slower than the initial patch that I had
shared, I
also observed the VM is as slow as stuck when I retried hotplugging upto
1024.
I will share more feedback if I have any.
I have shared one minor comment on patch 2/3, with that:
Reviewed-by: Yogesh Vyas <[email protected] <mailto:[email protected]>>
Tested-by: Yogesh Vyas <[email protected] <mailto:[email protected]>>
Thanks.
r`
