[src/trunk]: src/sys/uvm uvm_physseg: cluster fields used during RB tree look...

[ad <ad%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6712294dfdd5
branches:  trunk
changeset: 745901:6712294dfdd5
user:      ad <ad%NetBSD.org@localhost>
date:      Sun Mar 15 21:06:30 2020 +0000

description:
uvm_physseg: cluster fields used during RB tree lookup for PHYS_TO_VM_PAGE().

diffstat:

 sys/uvm/uvm_physseg.c |  11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diffs (38 lines):

diff -r 2ea0b6e9a530 -r 6712294dfdd5 sys/uvm/uvm_physseg.c
--- a/sys/uvm/uvm_physseg.c     Sun Mar 15 20:10:26 2020 +0000
+++ b/sys/uvm/uvm_physseg.c     Sun Mar 15 21:06:30 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_physseg.c,v 1.13 2019/12/21 14:41:44 ad Exp $ */
+/* $NetBSD: uvm_physseg.c,v 1.14 2020/03/15 21:06:30 ad Exp $ */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -87,12 +87,15 @@
  * uvm_physseg: describes one segment of physical memory
  */
 struct uvm_physseg {
+       /* used during RB tree lookup for PHYS_TO_VM_PAGE(). */
        struct  rb_node rb_node;        /* tree information */
        paddr_t start;                  /* PF# of first page in segment */
        paddr_t end;                    /* (PF# of last page in segment) + 1 */
+       struct  vm_page *pgs;           /* vm_page structures (from start) */
+
+       /* less performance sensitive fields. */
        paddr_t avail_start;            /* PF# of first free page in segment */
        paddr_t avail_end;              /* (PF# of last free page in segment) +1  */
-       struct  vm_page *pgs;           /* vm_page structures (from start) */
        struct  extent *ext;            /* extent(9) structure to manage pgs[] */
        int     free_list;              /* which free list they belong on */
        u_int   start_hint;             /* start looking for free pages here */
@@ -121,9 +124,9 @@
 struct uvm_physseg_graph {
        struct rb_tree rb_tree;         /* Tree for entries */
        int            nentries;        /* Number of entries */
-};
+} __aligned(COHERENCY_UNIT);
 
-static struct uvm_physseg_graph uvm_physseg_graph;
+static struct uvm_physseg_graph uvm_physseg_graph __read_mostly;
 
 /*
  * Note on kmem(9) allocator usage: