recipes/pandora-system/pandora-scripts/op_hugetlb.sh

   1 #!/bin/sh
   2
   3 if [ "$#" -ne "1" ]; then
   4         echo "usage: $0 <megabytes>"
   5         exit 1
   6 fi
   7
   8 if ! [ -e /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages ]; then
   9         echo "hugetlb error: no hugetlb support in kernel"
  10         exit 1
  11 fi
  12
  13 pages_needed=$(( ($1 + 1) / 2 ))
  14
  15 # find amount of pages reserved or in use
  16 pages_nr=`cat /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages`
  17 pages_free=`cat /sys/kernel/mm/hugepages/hugepages-2048kB/free_hugepages`
  18 pages_resv=`cat /sys/kernel/mm/hugepages/hugepages-2048kB/resv_hugepages`
  19
  20 pages_inuse_before=$(($pages_nr - $pages_free + $pages_resv))
  21 pages_inuse_after=$(($pages_inuse_before + $pages_needed))
  22
  23 for a in `seq 5`; do
  24         echo $pages_inuse_after > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
  25         sleep .2
  26         pages_nr=`cat /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages`
  27
  28         if [ "$pages_nr" = "$pages_inuse_after" ]; then
  29                 break
  30         fi
  31 done
  32
  33 if [ "$pages_nr" != "$pages_inuse_after" ]; then
  34         echo "hugetlb error: could not alloc $pages_inuse_after pages (got $pages_nr)"
  35 else
  36         echo "hugetlb: $pages_nr pages allocated."
  37 fi