config/kernel-blk-queue-unplug.m4

   1 dnl #
   2 dnl # 2.6.32-2.6.35 API - The BIO_RW_UNPLUG enum can be used as a hint
   3 dnl # to unplug the queue.
   4 dnl #
   5 AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_HAVE_BIO_RW_UNPLUG], [
   6         AC_MSG_CHECKING([whether the BIO_RW_UNPLUG enum is available])
   7         tmp_flags="$EXTRA_KCFLAGS"
   8         EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
   9         ZFS_LINUX_TRY_COMPILE([
  10                 #include <linux/blkdev.h>
  11         ],[
  12                 extern enum bio_rw_flags rw;
  13
  14                 rw = BIO_RW_UNPLUG;
  15         ],[
  16                 AC_MSG_RESULT(yes)
  17                 AC_DEFINE(HAVE_BLK_QUEUE_HAVE_BIO_RW_UNPLUG, 1,
  18                           [BIO_RW_UNPLUG is available])
  19         ],[
  20                 AC_MSG_RESULT(no)
  21         ])
  22         EXTRA_KCFLAGS="$tmp_flags"
  23 ])
  24
  25 AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_HAVE_BLK_PLUG], [
  26         AC_MSG_CHECKING([whether struct blk_plug is available])
  27         tmp_flags="$EXTRA_KCFLAGS"
  28         EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
  29         ZFS_LINUX_TRY_COMPILE([
  30                 #include <linux/blkdev.h>
  31         ],[
  32                 struct blk_plug plug;
  33
  34                 blk_start_plug(&plug);
  35                 blk_finish_plug(&plug);
  36         ],[
  37                 AC_MSG_RESULT(yes)
  38                 AC_DEFINE(HAVE_BLK_QUEUE_HAVE_BLK_PLUG, 1,
  39                           [struct blk_plug is available])
  40         ],[
  41                 AC_MSG_RESULT(no)
  42         ])
  43         EXTRA_KCFLAGS="$tmp_flags"
  44 ])