tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_order.tc

   1 #!/bin/sh
   2 # SPDX-License-Identifier: GPL-2.0
   3 # description: Change the ringbuffer sub-buffer order
   4 # requires: buffer_subbuf_order
   5 # flags: instance
   6
   7 get_buffer_data_size() {
   8         sed -ne 's/^.*data.*size:\([0-9][0-9]*\).*/\1/p' events/header_page
   9 }
  10
  11 get_buffer_data_offset() {
  12         sed -ne 's/^.*data.*offset:\([0-9][0-9]*\).*/\1/p' events/header_page
  13 }
  14
  15 get_event_header_size() {
  16         type_len=`sed -ne 's/^.*type_len.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event`
  17         time_len=`sed -ne 's/^.*time_delta.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event`
  18         array_len=`sed -ne 's/^.*array.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event`
  19         total_bits=$((type_len+time_len+array_len))
  20         total_bits=$((total_bits+7))
  21         echo $((total_bits/8))
  22 }
  23
  24 get_print_event_buf_offset() {
  25         sed -ne 's/^.*buf.*offset:\([0-9][0-9]*\).*/\1/p' events/ftrace/print/format
  26 }
  27
  28 event_header_size=`get_event_header_size`
  29 print_header_size=`get_print_event_buf_offset`
  30
  31 data_offset=`get_buffer_data_offset`
  32
  33 marker_meta=$((event_header_size+print_header_size))
  34
  35 make_str() {
  36         cnt=$1
  37         printf -- 'X%.0s' $(seq $cnt)
  38 }
  39
  40 write_buffer() {
  41         size=$1
  42
  43         str=`make_str $size`
  44
  45         # clear the buffer
  46         echo > trace
  47
  48         # write the string into the marker
  49         echo $str > trace_marker
  50
  51         echo $str
  52 }
  53
  54 test_buffer() {
  55         orde=$1
  56         page_size=$((4096<<order))
  57
  58         size=`get_buffer_data_size`
  59
  60         # the size must be greater than or equal to page_size - data_offset
  61         page_size=$((page_size-data_offset))
  62         if [ $size -lt $page_size ]; then
  63                 exit fail
  64         fi
  65
  66         # Now add a little more the meta data overhead will overflow
  67
  68         str=`write_buffer $size`
  69
  70         # Make sure the line was broken
  71         new_str=`awk ' /tracing_mark_write:/ { sub(/^.*tracing_mark_write: /,"");printf "%s", $0; exit}' trace`
  72
  73         if [ "$new_str" = "$str" ]; then
  74                 exit fail;
  75         fi
  76
  77         # Make sure the entire line can be found
  78         new_str=`awk ' /tracing_mark_write:/ { sub(/^.*tracing_mark_write: /,"");printf "%s", $0; }' trace`
  79
  80         if [ "$new_str" != "$str" ]; then
  81                 exit fail;
  82         fi
  83 }
  84
  85 ORIG=`cat buffer_subbuf_order`
  86
  87 # Could test bigger orders than 3, but then creating the string
  88 # to write into the ring buffer takes too long
  89 for a in 0 1 2 3 ; do
  90         echo $a > buffer_subbuf_order
  91         test_buffer $a
  92 done
  93
  94 echo $ORIG > buffer_subbuf_order
  95