Re: [PATCH 2/2] Add memory usage trace to diffrent hook points

[Dave Young <dyoung-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On 11/28/2012 06:33 AM, Vivek Goyal wrote:

> On Mon, Nov 26, 2012 at 10:38:52AM +0800, Dave Young wrote:
>>
>>
>> Port mkdumprd memory trace functions wrote by jstancek-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org
>> For kdump, memory usage tracing is important because there's limited
>> memory in kdump 2nd kernel.
>>
>> Add a rd.memdebug cmdline for this. set rd.memdebug=<X> will set the
>> debug level to X which is the debug verbose level.
>>
>> I added several trace point to the begin of several init hooks
>> At cmdline hooks I'm adding trace of "1+:mem 2+:iomem 3+:slab"
>> For other hooks I'm adding trace of "1:shortmem 2+:mem 3+:slab"
> 
> Not everybody knows what is kdump functionality for debugging. Can you
> please explain a bit more about the notion of 1+, 2+ etc.


Will update

> 
>>
>> This means:
>> rd.memdebug=1)
>>   cmdline hook: print /proc/meminfo
> 
> I think it is not a bad idea to print /proc/iomem for command line
> hook in case of rd.memdebug=1. It is just one time print, so does
> not hurt.


Ok. Will do

> 
>>   other hooks: print part of /proc/meminfo
> 
> We are calling it shortmem above. So  atleast put it in bracket so
> that it is not confusing.


Will do.

> 
> Thanks
> Vivek
> 
>> rd.memdebug=2)
>>   cmdline hook: show /proc/iomem and /proc/meminfo
>>   other hooks: print /proc/meminfo
>> rd.memdebug=3):
>>   cmdline hook: print /proc/iomem, /proc/meminfo and /proc/slabinfo
>>   other hooks: print /proc/meminfo and /proc/slabinfo
>> *):
>>   do not print any mem debug info
>>
>> Signed-off-by: Dave Young <dyoung-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
>> ---
>>  dracut.cmdline.7.asc                      |    4 +
>>  modules.d/98systemd/dracut-cmdline.sh     |    1 
>>  modules.d/98systemd/dracut-initqueue.sh   |    1 
>>  modules.d/98systemd/dracut-pre-pivot.sh   |    1 
>>  modules.d/98systemd/dracut-pre-trigger.sh |    1 
>>  modules.d/98systemd/dracut-pre-udev.sh    |    1 
>>  modules.d/99base/dracut-lib.sh            |   90 ++++++++++++++++++++++++++++++
>>  7 files changed, 99 insertions(+)
>>
>> --- dracut.orig/modules.d/98systemd/dracut-cmdline.sh
>> +++ dracut/modules.d/98systemd/dracut-cmdline.sh
>> @@ -18,6 +18,7 @@ type getarg >/dev/null 2>&1 || . /lib/dr
>>  
>>  source_conf /etc/conf.d
>>  
>> +make_trace_mem "hook cmdline" 1+:mem 2+:iomem 3+:slab
>>  # run scriptlets to parse the command line
>>  getarg 'rd.break=cmdline' -d 'rdbreak=cmdline' && emergency_shell -n cmdline "Break before cmdline"
>>  source_hook cmdline
>> --- dracut.orig/modules.d/98systemd/dracut-initqueue.sh
>> +++ dracut/modules.d/98systemd/dracut-initqueue.sh
>> @@ -10,6 +10,7 @@ type getarg >/dev/null 2>&1 || . /lib/dr
>>  
>>  source_conf /etc/conf.d
>>  
>> +make_trace_mem "hook initqueue" 1:shortmem 2+:mem 3+:slab
>>  getarg 'rd.break=initqueue' -d 'rdbreak=initqueue' && emergency_shell -n initqueue "Break before initqueue"
>>  
>>  RDRETRY=$(getarg rd.retry -d 'rd_retry=')
>> --- dracut.orig/modules.d/98systemd/dracut-pre-pivot.sh
>> +++ dracut/modules.d/98systemd/dracut-pre-pivot.sh
>> @@ -10,6 +10,7 @@ type getarg >/dev/null 2>&1 || . /lib/dr
>>  
>>  source_conf /etc/conf.d
>>  
>> +make_trace_mem "hook pre-pivot" 1:shortmem 2+:mem 3+:slab
>>  # pre pivot scripts are sourced just before we doing cleanup and switch over
>>  # to the new root.
>>  getarg 'rd.break=pre-pivot' 'rdbreak=pre-pivot' && emergency_shell -n pre-pivot "Break pre-pivot"
>> --- dracut.orig/modules.d/98systemd/dracut-pre-trigger.sh
>> +++ dracut/modules.d/98systemd/dracut-pre-trigger.sh
>> @@ -10,6 +10,7 @@ type getarg >/dev/null 2>&1 || . /lib/dr
>>  
>>  source_conf /etc/conf.d
>>  
>> +make_trace_mem "hook pre-trigger" 1:shortmem 2+:mem 3+:slab
>>  getargbool 0 rd.udev.info -n -y rdudevinfo && udevadm control --log-priority=info
>>  getargbool 0 rd.udev.debug -n -y rdudevdebug && udevadm control --log-priority=debug
>>  udevproperty "hookdir=$hookdir"
>> --- dracut.orig/modules.d/98systemd/dracut-pre-udev.sh
>> +++ dracut/modules.d/98systemd/dracut-pre-udev.sh
>> @@ -9,6 +9,7 @@ type getarg >/dev/null 2>&1 || . /lib/dr
>>  
>>  source_conf /etc/conf.d
>>  
>> +make_trace_mem "hook pre-udev" 1:shortmem 2+:mem 3+:slab
>>  # pre pivot scripts are sourced just before we doing cleanup and switch over
>>  # to the new root.
>>  getarg 'rd.break=pre-udev' 'rdbreak=pre-udev' && emergency_shell -n pre-udev "Break pre-udev"
>> --- dracut.orig/dracut.cmdline.7.asc
>> +++ dracut/dracut.cmdline.7.asc
>> @@ -134,6 +134,10 @@ Debug
>>      set -x for the dracut shell and logs to dmesg, console and
>>      _/run/initramfs/init.log_
>>  
>> +**rd.memdebug=[0-3]**::
>> +    print memory usage debug info, set the verbose level from 1 to 3
>> +    print nothing when set rd.memdebug=0
>> +
>>  **rd.break**::
>>      drop to a shell at the end
>>  
>> --- dracut.orig/modules.d/99base/dracut-lib.sh
>> +++ dracut/modules.d/99base/dracut-lib.sh
>> @@ -996,3 +996,93 @@ listlist() {
>>  are_lists_eq() {
>>      listlist "$1" "$2" "$3" "$4" && listlist "$1" "$3" "$2" "$4"
>>  }
>> +
>> +setmemdebug() {
>> +    if [ -z "$DEBUG_MEM_LEVEL" ]; then
>> +        export DEBUG_MEM_LEVEL=$(getargnum 0 3 rd.memdebug)
>> +    fi
>> +}
>> +
>> +setmemdebug
>> +
>> +# parameters: msg [trace_level:trace]...
>> +function make_trace_mem()
>> +{
>> +    msg=$1
>> +    shift
>> +    if [ "$DEBUG_MEM_LEVEL" -gt 0 ]; then
>> +        make_trace show_memstats $DEBUG_MEM_LEVEL "[debug_mem]" "$msg" "$@"
>> +    fi
>> +}
>> +
>> +# parameters: func log_level prefix msg [trace_level:trace]...
>> +function make_trace()
>> +{
>> +    func=$1
>> +    shift
>> +
>> +    log_level=`echo "$1" | grep -o '^[0-9]\+'`
>> +    shift
>> +
>> +    prefix=$1
>> +    shift
>> +
>> +    msg=$1
>> +    shift
>> +
>> +    if [ -z "$log_level" ]; then
>> +        return
>> +    fi
>> +
>> +    msg=`echo "$msg" | sed 's/^\s\+//'`
>> +
>> +    msg_printed=0
>> +    while [ $# -gt 0 ]; do
>> +        trace_level=`echo "$1" | grep -o '^[0-9]\+'`
>> +        trace_in_higher_levels=`echo "$1" | grep -o '+'`
>> +        trace=`echo $1 | sed "s/^.*://"`
>> +
>> +        if [ -z "$trace_level" ]; then
>> +            trace_level=0
>> +        fi
>> +
>> +        insert_trace=0
>> +        if [ -n "$trace_in_higher_levels" ]; then
>> +            if [ "$log_level" -ge "$trace_level" ]; then
>> +                insert_trace=1
>> +            fi
>> +        else
>> +            if [ "$log_level" -eq "$trace_level" ]; then
>> +                insert_trace=1
>> +            fi
>> +        fi
>> +
>> +        if [ $insert_trace -eq 1 ]; then
>> +            if [ $msg_printed -eq 0 ]; then
>> +                echo "$prefix $msg"
>> +                msg_printed=1
>> +            fi
>> +            $func $trace
>> +        fi
>> +        shift
>> +    done
>> +}
>> +
>> +# parameters: type
>> +show_memstats()
>> +{
>> +    case $1 in
>> +        shortmem)
>> +            cat /proc/meminfo  | grep -e "^MemFree" -e "^Cached" -e "^Slab"
>> +            ;;
>> +        mem)
>> +            cat /proc/meminfo
>> +            ;;
>> +        slab)
>> +            cat /proc/slabinfo
>> +            ;;
>> +        iomem)
>> +            cat /proc/iomem
>> +            ;;
>> +    esac
>> +}
>> --
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-- 
Thanks
Dave