Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Oleksandr Natalenko <oleksandr@redhat.com>
To:     linux-kernel@vger.kernel.org
Cc:     Kirill Tkhai <ktkhai@virtuozzo.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Michal Hocko <mhocko@suse.com>,
        Matthew Wilcox <willy@infradead.org>,
        Pavel Tatashin <pasha.tatashin@soleen.com>,
        Timofey Titovets <nefelim4ag@gmail.com>,
        Aaron Tomlin <atomlin@redhat.com>,
        Grzegorz Halat <ghalat@redhat.com>, linux-mm@kvack.org
Subject: [PATCH RFC v2 4/4] mm/ksm: add force merging/unmerging documentation
Date:   Tue, 14 May 2019 15:16:54 +0200
Message-Id: <20190514131654.25463-5-oleksandr@redhat.com>
In-Reply-To: <20190514131654.25463-1-oleksandr@redhat.com>
References: <20190514131654.25463-1-oleksandr@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Document respective sysfs knob.

Signed-off-by: Oleksandr Natalenko <oleksandr@redhat.com>
---
 Documentation/admin-guide/mm/ksm.rst | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst
index 9303786632d1..4302b92910ec 100644
--- a/Documentation/admin-guide/mm/ksm.rst
+++ b/Documentation/admin-guide/mm/ksm.rst
@@ -78,6 +78,17 @@ KSM daemon sysfs interface
 The KSM daemon is controlled by sysfs files in ``/sys/kernel/mm/ksm/``,
 readable by all but writable only by root:
 
+force_madvise
+        write-only control to force merging/unmerging for specific
+        task.
+
+        To mark the VMAs as mergeable, use:
+        ``echo PID > /sys/kernel/mm/ksm/force_madvise``
+
+        To unmerge all the VMAs, use:
+        ``echo -PID > /sys/kernel/mm/ksm/force_madvise``
+        (note the prepending "minus")
+
 pages_to_scan
         how many pages to scan before ksmd goes to sleep
         e.g. ``echo 100 > /sys/kernel/mm/ksm/pages_to_scan``.
-- 
2.21.0