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>

1 files changed, 19 insertions, 12 deletions

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 1ffd97ae26d7..c280a02ea11e 100644
--- 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;