On 9/8/26 8:50 PM, Kiryl Shutsemau wrote:
From: "Kiryl Shutsemau (Meta)" <[email protected]> A khugepaged test has to tell "not collapsed" from "not scanned yet", and nothing in the selftests can. wait_for_scan() in khugepaged.c comes closest: it polls full_scans until the counter has advanced by two, since the pass in progress may already have passed the test's mm. But it only returns in time if scan_sleep_millisecs happens to be short, and it is private to that one test. Add khugepaged_full_pass() to hugepage_settings, built on the same advance-by-two wait but driven through sysfs: a store to scan_sleep_millisecs wakes the daemon, so the barrier completes whatever the scan cadence. A store made while the daemon is scanning rather than sleeping is lost, so the helper keeps storing until the pass lands. One wake completes one pass only if pages_to_scan covers every mm on the list, so callers need it large. Settings pushes must not start passes of their own. A store to either sleep knob wakes the daemon, so thp_write_settings() now writes a khugepaged knob only when its value changes. Assisted-by: LLM Tested-by: Muhammad Usama Anjum <[email protected]> Signed-off-by: Kiryl Shutsemau (Meta) <[email protected]> ---
Make sense to me. Reviewed-by: Baolin Wang <[email protected]>
