cvs commit: src/sys/vm vm_fault.c

[Alan Cox]

alc         2007-07-20 06:55:12 UTC

  FreeBSD src repository

  Modified files:
    sys/vm               vm_fault.c 
  Log:
  Two changes to vm_fault_additional_pages():
  
  1. Rewrite the backward scan.  Specifically, reverse the order in which
     pages are allocated so that upon failure it is never necessary to
     free pages that were just allocated.  Moreover, any allocated pages
     can be put to use.  This makes the backward scan behave just like the
     forward scan.
  
  2. Eliminate an explicit, unsynchronized check for low memory before
     calling vm_page_alloc().  It serves no useful purpose.  It is, in
     effect, optimizing the uncommon case at the expense of the common
     case.
  
  Approved by:    re (hrs)
  MFC after:      3 weeks
  
  Revision  Changes    Path
  1.235     +11 -19    src/sys/vm/vm_fault.c