Lab5: RTOS modifications

預期目標

• 搭配第五周</embedded/2012w4>_課程進度

預先準備

• 取得最新 Labs 內容 (與之前 Lab3</embedded/Lab3>_ 操作相似)：

.. code-block:: prettyprint

git clone git://gitcafe.com/embedded2012/Labs.git
cd Labs/Lab-5

Code Coverage

• GNU code coverage tool gcov<http://gcc.gnu.org/onlinedocs/gcc/Gcov.html>_ is generally used to dump the coverage data when the program exits
  • for some embedded systems or for server processes you need a means to dump coverage data of particular situations, i.e. when a client connects.
• Code quality analysis for embedded systems
  • Memory management with Valgrind
  • Code coverage testing with Gcov
• Code Quality Analysis Toolset for Embedded Systems<http://www.eclipsecon.org/2008/sub/attachments/Code_Quality_Analysis_Toolset_for_Embedded_Systems.pdf>_
• Using gcov and lcov<http://www.slideshare.net/maguschen/using-gcov-and-lcov>_
• 新酷音輸入法系統的核心函式庫 (libchewing) 分析
  • http://kanru.info/chewing/lcov-check

執行時期輸出 gcov 資料

• Dumping gcov data at runtime - a simple example<https://www.osadl.org/fileadmin/dam/interface/docbook/howtos/coverage.pdf>_
• Instructions for invoking gcov

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make make run gcov hello

• Reference output

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File ’hello.c’ Lines executed:100.00% of 15 hello.c:creating ’hello.c.gcov’

• Analyze gcov output

.. code-block:: prettyprint

tail hello.c.gcov

• Reference output

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1:
34: new_action.sa_flags = 0;
-:
35:
1:
36: sigaction(SIGUSR1, NULL, &old_action);
1:
37: if (old_action.sa_handler != SIG_IGN)
1:
38:
sigaction (SIGUSR1, &new_action, NULL);
-:
39:
-:
40: /* infinite loop - to exemplify dumping coverage data while program runs */
186275468151:
41: for(n = 0; ; n++)
372550936302:
42:
i++;
-:
43:}

作業

• Lab-5/filesys
• 整合檔案系統到 FreeRTOS 中，並在 UART 顯示檔案系統中 test.txt 的內容
• 提示：
  • 會需要修改到 linker script 以及 SRAM 的配置
  • 會需要補充基本的標準 C 函式，讓系統得以運作