+++ /dev/null
-#!/bin/sh
-
-# Try to find out kernel modules with large total memory allocation during loading.
-# For large slab allocation, it will fall into buddy, also not trace "mm_page_free"
-# considering large free is quite rare for module_init, thus saving tons of events
-# to avoid trace data overwritten.
-#
-# Therefore, tracing "mm_page_alloc"alone should be enough for the purpose.
-
-# "sys/kernel/tracing" has the priority if exists.
-get_trace_base() {
- # trace access through debugfs would be obsolete if "/sys/kernel/tracing" is available.
- if [ -d "/sys/kernel/tracing" ]; then
- echo "/sys/kernel"
- else
- echo "/sys/kernel/debug"
- fi
-}
-
-# We want to enable these trace events.
-get_want_events() {
- echo "module:module_put module:module_load kmem:mm_page_alloc"
-}
-
-get_event_filter() {
- echo "comm == systemd-udevd || comm == modprobe || comm == insmod"
-}
-
-is_trace_ready() {
- local trace_base want_events current_events
-
- trace_base=$(get_trace_base)
- ! [ -f "$trace_base/tracing/trace" ] && return 1
-
- [ "$(cat $trace_base/tracing/tracing_on)" -eq 0 ] && return 1
-
- # Also check if trace events were properly setup.
- want_events=$(get_want_events)
- current_events=$(echo $(cat $trace_base/tracing/set_event))
- [ "$current_events" != "$want_events" ] && return 1
-
- return 0
-}
-
-prepare_trace() {
- local trace_base
-
- trace_base=$(get_trace_base)
- # old debugfs interface case.
- if ! [ -d "$trace_base/tracing" ]; then
- mount none -t debugfs $trace_base
- # new tracefs interface case.
- elif ! [ -f "$trace_base/tracing/trace" ]; then
- mount none -t tracefs "$trace_base/tracing"
- fi
-
- if ! [ -f "$trace_base/tracing/trace" ]; then
- echo "WARN: Mount trace failed for kernel module memory analyzing."
- return 1
- fi
-
- # Active all the wanted trace events.
- echo "$(get_want_events)" > $trace_base/tracing/set_event
-
- # There are three kinds of known applications for module loading:
- # "systemd-udevd", "modprobe" and "insmod".
- # Set them as the global events filter.
- # NOTE: Some kernel may not support this format of filter, anyway
- # the operation will fail and it doesn't matter.
- echo "$(get_event_filter)" > $trace_base/tracing/events/kmem/filter 2>&1
- echo "$(get_event_filter)" > $trace_base/tracing/events/module/filter 2>&1
-
- # Set the number of comm-pid if supported.
- if [ -f "$trace_base/tracing/saved_cmdlines_size" ]; then
- # Thanks to filters, 4096 is big enough(also well supported).
- echo 4096 > $trace_base/tracing/saved_cmdlines_size
- fi
-
- # Enable and clear trace data for the first time.
- echo 1 > $trace_base/tracing/tracing_on
- echo > $trace_base/tracing/trace
- echo "Prepare trace success."
- return 0
-}
-
-order_to_pages()
-{
- local pages=1
- local order=$1
-
- while [ "$order" != 0 ]; do
- order=$((order-1))
- pages=$(($pages*2))
- done
-
- echo $pages
-}
-
-parse_trace_data() {
- local module_name tmp_eval pages
-
- cat "$(get_trace_base)/tracing/trace" | while read pid cpu flags ts function args
- do
- # Skip comment lines
- if [ "$pid" = "#" ]; then
- continue
- fi
-
- pid=${pid##*-}
- function=${function%:}
- if [ "$function" = "module_load" ]; then
- # One module is being loaded, save the task pid for tracking.
- # Remove the trailing after whitespace, there may be the module flags.
- module_name=${args%% *}
- # Mark current_module to track the task.
- eval current_module_$pid="$module_name"
- tmp_eval=$(eval echo '${module_loaded_'${module_name}'}')
- if [ -n "$tmp_eval" ]; then
- echo "WARN: \"$module_name\" was loaded multiple times!"
- fi
- eval unset module_loaded_$module_name
- eval nr_alloc_pages_$module_name=0
- continue
- fi
-
- module_name=$(eval echo '${current_module_'${pid}'}')
- if [ -z "$module_name" ]; then
- continue
- fi
-
- # Once we get here, the task is being tracked(is loading a module).
- if [ "$function" = "module_put" ]; then
- # Mark the module as loaded when the first module_put event happens after module_load.
- tmp_eval=$(eval echo '${nr_alloc_pages_'${module_name}'}')
- echo "$tmp_eval pages consumed by \"$module_name\""
- eval module_loaded_$module_name=1
- # Module loading finished, so untrack the task.
- eval unset current_module_$pid
- eval unset nr_alloc_pages_$module_name
- continue
- fi
-
- if [ "$function" = "mm_page_alloc" ]; then
- # Get order first, then convert to actual pages.
- pages=$(echo $args | sed -e 's/.*order=\([0-9]*\) .*/\1/')
- pages=$(order_to_pages "$pages")
- tmp_eval=$(eval echo '${nr_alloc_pages_'${module_name}'}')
- eval nr_alloc_pages_$module_name="$(($tmp_eval+$pages))"
- fi
- done
-}
-
-cleanup_trace() {
- local trace_base
-
- if is_trace_ready; then
- trace_base=$(get_trace_base)
- echo 0 > $trace_base/tracing/tracing_on
- echo > $trace_base/tracing/trace
- echo > $trace_base/tracing/set_event
- echo 0 > $trace_base/tracing/events/kmem/filter
- echo 0 > $trace_base/tracing/events/module/filter
- fi
-}
-
-show_usage() {
- echo "Find out kernel modules with large memory consumption during loading based on trace."
- echo "Usage:"
- echo "1) run it first to setup trace."
- echo "2) run again to parse the trace data if any."
- echo "3) run with \"--cleanup\" option to cleanup trace after use."
-}
-
-if [ "$1" = "--help" ]; then
- show_usage
- exit 0
-fi
-
-if [ "$1" = "--cleanup" ]; then
- cleanup_trace
- exit 0
-fi
-
-if is_trace_ready ; then
- echo "tracekomem - Rough memory consumption by loading kernel modules (larger value with better accuracy)"
- parse_trace_data
-else
- prepare_trace
-fi
-
-exit $?
projects / thirdparty / dracut.git / commitdiff
