Re: [PATCH] mm: vmscan: abort proactive reclaim early when freezing

[Richard Chang]

On Wed, Jul 8, 2026 at 3:48 AM Shakeel Butt <shakeel.butt@xxxxxxxxx> wrote:
>
> Can you please explain how freezing operation was delayed due to proactive
> reclaim?
>
Hi Shakeel,

When system suspend is initiated, the Power Management (PM) freezer
attempts to freeze all user-space processes by calling
freeze_processes(), signaling user space processes to enter the
refrigerator. When a user-space task writes to memory.reclaim to
trigger proactive reclaim, it executes in kernel context and enters
the reclaim loop. Currently the task does not check  signal_pending()
within the inner loops, it cannot abort the reclaim pass early. It
continues reclaiming memory, ignoring the freeze request. The PM
freezer waits for all tasks to freeze. If the proactive reclaim task
remains in the inner loops longer than the freeze timeout, the freezer
times out, and suspend fails.