mm: init: report on last-nid information stored in page->flags

Answering the question "how much space remains in the page->flags" is
time-consuming.  mminit_loglevel can help answer the question but it
does not take last_nid information into account.  This patch corrects it
and while there it corrects the messages related to page flag usage,
pgshifts and node/zone id.  When applied the relevant output looks
something like this but will depend on the kernel configuration.

  mminit::pageflags_layout_widths Section 0 Node 9 Zone 2 Lastnid 9 Flags 25
  mminit::pageflags_layout_shifts Section 19 Node 9 Zone 2 Lastnid 9
  mminit::pageflags_layout_pgshifts Section 0 Node 55 Zone 53 Lastnid 44
  mminit::pageflags_layout_nodezoneid Node/Zone ID: 64 -> 53
  mminit::pageflags_layout_usage location: 64 -> 44 layout 44 -> 25 unused 25 -> 0 page-flags

Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 1ffd97ae26d7444a6294c1c2e856b8cf8acbac02..c280a02ea11ea2ce79113c5487ce09044652ac80 100644 (file)
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -69,34 +69,41 @@ void __init mminit_verify_pageflags_layout(void)
        unsigned long or_mask, add_mask;
 
        shift = 8 * sizeof(unsigned long);
-       width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH;
+       width = shift - SECTIONS_WIDTH - NODES_WIDTH - ZONES_WIDTH - LAST_NID_SHIFT;
        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_widths",
-               "Section %d Node %d Zone %d Flags %d\n",
+               "Section %d Node %d Zone %d Lastnid %d Flags %d\n",
                SECTIONS_WIDTH,
                NODES_WIDTH,
                ZONES_WIDTH,
+               LAST_NID_WIDTH,
                NR_PAGEFLAGS);
        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_shifts",
-               "Section %d Node %d Zone %d\n",
+               "Section %d Node %d Zone %d Lastnid %d\n",
                SECTIONS_SHIFT,
                NODES_SHIFT,
-               ZONES_SHIFT);
-       mminit_dprintk(MMINIT_TRACE, "pageflags_layout_offsets",
-               "Section %lu Node %lu Zone %lu\n",
+               ZONES_SHIFT,
+               LAST_NID_SHIFT);
+       mminit_dprintk(MMINIT_TRACE, "pageflags_layout_pgshifts",
+               "Section %lu Node %lu Zone %lu Lastnid %lu\n",
                (unsigned long)SECTIONS_PGSHIFT,
                (unsigned long)NODES_PGSHIFT,
-               (unsigned long)ZONES_PGSHIFT);
-       mminit_dprintk(MMINIT_TRACE, "pageflags_layout_zoneid",
-               "Zone ID: %lu -> %lu\n",
-               (unsigned long)ZONEID_PGOFF,
-               (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT));
+               (unsigned long)ZONES_PGSHIFT,
+               (unsigned long)LAST_NID_PGSHIFT);
+       mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodezoneid",
+               "Node/Zone ID: %lu -> %lu\n",
+               (unsigned long)(ZONEID_PGOFF + ZONEID_SHIFT),
+               (unsigned long)ZONEID_PGOFF);
        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_usage",
-               "location: %d -> %d unused %d -> %d flags %d -> %d\n",
+               "location: %d -> %d layout %d -> %d unused %d -> %d page-flags\n",
                shift, width, width, NR_PAGEFLAGS, NR_PAGEFLAGS, 0);
 #ifdef NODE_NOT_IN_PAGE_FLAGS
        mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
                "Node not in page flags");
 #endif
+#ifdef LAST_NID_NOT_IN_PAGE_FLAGS
+       mminit_dprintk(MMINIT_TRACE, "pageflags_layout_nodeflags",
+               "Last nid not in page flags");
+#endif
 
        if (SECTIONS_WIDTH) {
                shift -= SECTIONS_WIDTH;