From: Michael Jeanson <mjeanson@efficios.com>
Date: Wed, 8 Jun 2022 16:56:36 +0000 (-0400)
Subject: fix: mm/page_alloc: fix tracepoint mm_page_alloc_zone_locked() (v5.19)
X-Git-Url: http://git.lttng.org./?a=commitdiff_plain;ds=sidebyside;h=6229bbaa423832f6b7c7a658ad11e1d4242752ff;hp=6229bbaa423832f6b7c7a658ad11e1d4242752ff;p=lttng-modules.git

fix: mm/page_alloc: fix tracepoint mm_page_alloc_zone_locked() (v5.19)

See upstream commit :

  commit 10e0f7530205799e7e971aba699a7cb3a47456de
  Author: Wonhyuk Yang <vvghjk1234@gmail.com>
  Date:   Thu May 19 14:08:54 2022 -0700

    mm/page_alloc: fix tracepoint mm_page_alloc_zone_locked()

    Currently, trace point mm_page_alloc_zone_locked() doesn't show correct
    information.

    First, when alloc_flag has ALLOC_HARDER/ALLOC_CMA, page can be allocated
    from MIGRATE_HIGHATOMIC/MIGRATE_CMA.  Nevertheless, tracepoint use
    requested migration type not MIGRATE_HIGHATOMIC and MIGRATE_CMA.

    Second, after commit 44042b4498728 ("mm/page_alloc: allow high-order pages
    to be stored on the per-cpu lists") percpu-list can store high order
    pages.  But trace point determine whether it is a refiil of percpu-list by
    comparing requested order and 0.

    To handle these problems, make mm_page_alloc_zone_locked() only be called
    by __rmqueue_smallest with correct migration type.  With a new argument
    called percpu_refill, it can show roughly whether it is a refill of
    percpu-list.

Change-Id: I2e4a57393757f12b9c5a4566c4d1102ee2474a09
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---