From 2f84b39f48476615186af5b3220ad5a2c756679b Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Tue, 19 Dec 2023 13:54:29 -0500 Subject: tracing: Update subbuffer with kilobytes not page order Using page order for deciding what the size of the ring buffer sub buffers are is exposing a bit too much of the implementation. Although the sub buffers are only allocated in orders of pages, allow the user to specify the minimum size of each sub-buffer via kilobytes like they can with the buffer size itself. If the user specifies 3 via: echo 3 > buffer_subbuf_size_kb Then the sub-buffer size will round up to 4kb (on a 4kb page size system). If they specify: echo 6 > buffer_subbuf_size_kb The sub-buffer size will become 8kb. and so on. Link: https://lore.kernel.org/linux-trace-kernel/20231219185631.809766769@goodmis.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Tzvetomir Stoyanov Cc: Vincent Donnefort Cc: Kent Overstreet Signed-off-by: Steven Rostedt (Google) --- .../ftrace/test.d/00basic/ringbuffer_order.tc | 95 ---------------------- .../test.d/00basic/ringbuffer_subbuf_size.tc | 95 ++++++++++++++++++++++ 2 files changed, 95 insertions(+), 95 deletions(-) delete mode 100644 tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_order.tc create mode 100644 tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_subbuf_size.tc (limited to 'tools/testing/selftests/ftrace') diff --git a/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_order.tc b/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_order.tc deleted file mode 100644 index ecbcc810e6c1..000000000000 --- a/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_order.tc +++ /dev/null @@ -1,95 +0,0 @@ -#!/bin/sh -# SPDX-License-Identifier: GPL-2.0 -# description: Change the ringbuffer sub-buffer order -# requires: buffer_subbuf_order -# flags: instance - -get_buffer_data_size() { - sed -ne 's/^.*data.*size:\([0-9][0-9]*\).*/\1/p' events/header_page -} - -get_buffer_data_offset() { - sed -ne 's/^.*data.*offset:\([0-9][0-9]*\).*/\1/p' events/header_page -} - -get_event_header_size() { - type_len=`sed -ne 's/^.*type_len.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` - time_len=`sed -ne 's/^.*time_delta.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` - array_len=`sed -ne 's/^.*array.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` - total_bits=$((type_len+time_len+array_len)) - total_bits=$((total_bits+7)) - echo $((total_bits/8)) -} - -get_print_event_buf_offset() { - sed -ne 's/^.*buf.*offset:\([0-9][0-9]*\).*/\1/p' events/ftrace/print/format -} - -event_header_size=`get_event_header_size` -print_header_size=`get_print_event_buf_offset` - -data_offset=`get_buffer_data_offset` - -marker_meta=$((event_header_size+print_header_size)) - -make_str() { - cnt=$1 - printf -- 'X%.0s' $(seq $cnt) -} - -write_buffer() { - size=$1 - - str=`make_str $size` - - # clear the buffer - echo > trace - - # write the string into the marker - echo $str > trace_marker - - echo $str -} - -test_buffer() { - orde=$1 - page_size=$((4096< buffer_subbuf_order - test_buffer $a -done - -echo $ORIG > buffer_subbuf_order - diff --git a/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_subbuf_size.tc b/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_subbuf_size.tc new file mode 100644 index 000000000000..d44d09a33a74 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/00basic/ringbuffer_subbuf_size.tc @@ -0,0 +1,95 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Change the ringbuffer sub-buffer size +# requires: buffer_subbuf_size_kb +# flags: instance + +get_buffer_data_size() { + sed -ne 's/^.*data.*size:\([0-9][0-9]*\).*/\1/p' events/header_page +} + +get_buffer_data_offset() { + sed -ne 's/^.*data.*offset:\([0-9][0-9]*\).*/\1/p' events/header_page +} + +get_event_header_size() { + type_len=`sed -ne 's/^.*type_len.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` + time_len=`sed -ne 's/^.*time_delta.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` + array_len=`sed -ne 's/^.*array.*:[^0-9]*\([0-9][0-9]*\).*/\1/p' events/header_event` + total_bits=$((type_len+time_len+array_len)) + total_bits=$((total_bits+7)) + echo $((total_bits/8)) +} + +get_print_event_buf_offset() { + sed -ne 's/^.*buf.*offset:\([0-9][0-9]*\).*/\1/p' events/ftrace/print/format +} + +event_header_size=`get_event_header_size` +print_header_size=`get_print_event_buf_offset` + +data_offset=`get_buffer_data_offset` + +marker_meta=$((event_header_size+print_header_size)) + +make_str() { + cnt=$1 + printf -- 'X%.0s' $(seq $cnt) +} + +write_buffer() { + size=$1 + + str=`make_str $size` + + # clear the buffer + echo > trace + + # write the string into the marker + echo $str > trace_marker + + echo $str +} + +test_buffer() { + size_kb=$1 + page_size=$((size_kb*1024)) + + size=`get_buffer_data_size` + + # the size must be greater than or equal to page_size - data_offset + page_size=$((page_size-data_offset)) + if [ $size -lt $page_size ]; then + exit fail + fi + + # Now add a little more the meta data overhead will overflow + + str=`write_buffer $size` + + # Make sure the line was broken + new_str=`awk ' /tracing_mark_write:/ { sub(/^.*tracing_mark_write: /,"");printf "%s", $0; exit}' trace` + + if [ "$new_str" = "$str" ]; then + exit fail; + fi + + # Make sure the entire line can be found + new_str=`awk ' /tracing_mark_write:/ { sub(/^.*tracing_mark_write: /,"");printf "%s", $0; }' trace` + + if [ "$new_str" != "$str" ]; then + exit fail; + fi +} + +ORIG=`cat buffer_subbuf_size_kb` + +# Could test bigger sizes than 32K, but then creating the string +# to write into the ring buffer takes too long +for a in 4 8 16 32 ; do + echo $a > buffer_subbuf_size_kb + test_buffer $a +done + +echo $ORIG > buffer_subbuf_size_kb + -- cgit v1.2.3-59-g8ed1b