Re: [PATCHv2] kdump-lib.sh: introduce functions to return recommened mem size

[Kairui Song]

Looks good to me!

On Thu, Feb 4, 2021 at 9:45 AM Pingfan Liu <piliu(a)redhat.com&gt; wrote:
>  There is requirement to decide the recommended memory size for the current
>  system. Ant the algorithm is based on /proc/iomem, so it can align with the
>  algorithm used by reserve_crashkernel() in kernel.
>
>  Signed-off-by: Pingfan Liu <piliu(a)redhat.com&gt;
>  ---
>   kdump-lib.sh | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 69 insertions(+)
>
>  diff --git a/kdump-lib.sh b/kdump-lib.sh
>  index d2801da..a4bab39 100755
>  --- a/kdump-lib.sh
>  +++ b/kdump-lib.sh
>  @@ -823,3 +823,72 @@ prepare_cmdline()
>
>       echo ${cmdline}
>   }
>  +
>  +#get system memory size in the unit of GB
>  +get_system_size()
>  +{
>  +       result=$(cat /proc/iomem  | grep "System RAM" | awk -F ":"
> '{ print $1 }' | tr [:lower:] [:upper:] | paste -sd+)
>  +       result="+$result"
>  +       # replace '-' with '+0x' and '+' with '-0x'
>  +       sum=$( echo $result | sed -e 's/-/K0x/g' | sed -e 's/+/-0x/g' |
> sed -e 's/K/+/g' )
>  +       size=$(printf "%d\n" $(($sum)))
>  +       let size=$size/1024/1024/1024
>  +
>  +       echo $size
>  +}
>  +
>  +get_recommend_size()
>  +{
>  +       local mem_size=$1
>  +       local _ck_cmdline=$2
>  +       local OLDIFS="$IFS"
>  +
>  +       last_sz=""
>  +       last_unit=""
>  +
>  +       IFS=','
>  +       for i in $_ck_cmdline
>  +       do
>  +               end=$(echo $i | awk -F "-" '{ print $2 }' | awk -F
> ":" '{ print $1 }')
>  +               recommend=$(echo $i | awk -F "-" '{ print $2 }' | awk
> -F ":" '{ print $2 }')
>  +               size=${end: : -1}
>  +               unit=${end: -1}
>  +               if [ $unit == 'T' ]; then
>  +                       let size=$size*1024
>  +               fi
>  +               if [ $mem_size -lt $size ]; then
>  +                       echo $recommend
>  +                       IFS="$OLDIFS"
>  +                       return
>  +               fi
>  +       done
>  +       IFS="$OLDIFS"
>  +}
>  +
>  +# return recommended size based on current system RAM size
>  +kdump_get_arch_recommend_size()
>  +{
>  +       if ! [[ -r "/proc/iomem" ]] ; then
>  +               echo "Error, can not access /proc/iomem."
>  +               return 1
>  +       fi
>  +       arch=$(lscpu | grep Architecture | awk -F ":" '{ print $2 }' |
> tr [:lower:] [:upper:])
>  +
>  +       if [ $arch == "X86_64" ] || [ $arch == "S390" ]; then
>  +               ck_cmdline="1G-4G:160M,4G-64G:192M,64G-1T:256M,1T-:512M"
>  +       elif [ $arch == "ARM64" ]; then
>  +               ck_cmdline="2G-:448M"
>  +       elif [ $arch == "PPC64LE" ]; then
>  +               if is_fadump_capable; then
>  +                      
> ck_cmdline="4G-16G:768M,16G-64G:1G,64G-128G:2G,128G-1T:4G,1T-2T:6G,2T-4T:12G,4T-8T:20G,8T-16T:36G,16T-32T:64G,32T-64T:128G,64T-:180G"
>  +               else
>  +                      
> ck_cmdline="2G-4G:384M,4G-16G:512M,16G-64G:1G,64G-128G:2G,128G-:4G"
>  +               fi
>  +       fi
>  +
>  +       ck_cmdline=$( echo $ck_cmdline | sed -e 's/-:/-102400T:/g' )
>  +       sys_mem=$(get_system_size)
>  +       result=$( get_recommend_size $sys_mem "$ck_cmdline" )
>  +       echo $result
>  +       return 0
>  +}
>  --
>  2.29.2
>  
There are a few trivial indent problem, I'll fix it when merging.

Acked-by: Kairui Song <kasong(a)redhat.com&gt;

-- 
Best Regards,
Kairui Song