diff options
Diffstat (limited to 'documentation/kernel-dev')
| -rw-r--r-- | documentation/kernel-dev/kernel-dev-common.xml | 65 |
1 files changed, 44 insertions, 21 deletions
diff --git a/documentation/kernel-dev/kernel-dev-common.xml b/documentation/kernel-dev/kernel-dev-common.xml index 50e420c8d6..bfc82e2451 100644 --- a/documentation/kernel-dev/kernel-dev-common.xml +++ b/documentation/kernel-dev/kernel-dev-common.xml | |||
| @@ -1752,28 +1752,41 @@ | |||
| 1752 | <title>Fine-Tuning the Kernel Configuration File</title> | 1752 | <title>Fine-Tuning the Kernel Configuration File</title> |
| 1753 | 1753 | ||
| 1754 | <para> | 1754 | <para> |
| 1755 | You can make sure the <filename>.config</filename> file is as lean or efficient as | 1755 | You can make sure the <filename>.config</filename> file is as |
| 1756 | possible by reading the output of the kernel configuration fragment audit, | 1756 | lean or efficient as possible by reading the output of the |
| 1757 | noting any issues, making changes to correct the issues, and then repeating. | 1757 | kernel configuration fragment audit, noting any issues, making |
| 1758 | changes to correct the issues, and then repeating. | ||
| 1758 | </para> | 1759 | </para> |
| 1759 | 1760 | ||
| 1760 | <para> | 1761 | <para> |
| 1761 | As part of the kernel build process, the | 1762 | As part of the kernel build process, the |
| 1762 | <filename>do_kernel_configcheck</filename> task runs. | 1763 | <filename>do_kernel_configcheck</filename> task runs. |
| 1763 | This task validates the kernel configuration by checking the final | 1764 | This task validates the kernel configuration by checking the |
| 1764 | <filename>.config</filename> file against the input files. | 1765 | final <filename>.config</filename> file against the input |
| 1765 | During the check, the task produces warning messages for the following | 1766 | files. |
| 1766 | issues: | 1767 | During the check, the task produces warning messages for the |
| 1768 | following issues: | ||
| 1767 | <itemizedlist> | 1769 | <itemizedlist> |
| 1768 | <listitem><para>Requested options that did not make the final | 1770 | <listitem><para> |
| 1769 | <filename>.config</filename> file.</para></listitem> | 1771 | Requested options that did not make the final |
| 1770 | <listitem><para>Configuration items that appear twice in the same | 1772 | <filename>.config</filename> file. |
| 1771 | configuration fragment.</para></listitem> | 1773 | </para></listitem> |
| 1772 | <listitem><para>Configuration items tagged as "required" that were overridden. | 1774 | <listitem><para> |
| 1775 | Configuration items that appear twice in the same | ||
| 1776 | configuration fragment. | ||
| 1777 | </para></listitem> | ||
| 1778 | <listitem><para> | ||
| 1779 | Configuration items tagged as "required" that were | ||
| 1780 | overridden. | ||
| 1781 | </para></listitem> | ||
| 1782 | <listitem><para> | ||
| 1783 | A board overrides a non-board specific option. | ||
| 1784 | </para></listitem> | ||
| 1785 | <listitem><para> | ||
| 1786 | Listed options not valid for the kernel being | ||
| 1787 | processed. | ||
| 1788 | In other words, the option does not appear anywhere. | ||
| 1773 | </para></listitem> | 1789 | </para></listitem> |
| 1774 | <listitem><para>A board overrides a non-board specific option.</para></listitem> | ||
| 1775 | <listitem><para>Listed options not valid for the kernel being processed. | ||
| 1776 | In other words, the option does not appear anywhere.</para></listitem> | ||
| 1777 | </itemizedlist> | 1790 | </itemizedlist> |
| 1778 | <note> | 1791 | <note> |
| 1779 | The <filename>do_kernel_configcheck</filename> task can | 1792 | The <filename>do_kernel_configcheck</filename> task can |
| @@ -1793,11 +1806,17 @@ | |||
| 1793 | <para> | 1806 | <para> |
| 1794 | To streamline the configuration, do the following: | 1807 | To streamline the configuration, do the following: |
| 1795 | <orderedlist> | 1808 | <orderedlist> |
| 1796 | <listitem><para>Start with a full configuration that you | 1809 | <listitem><para> |
| 1797 | know works - it builds and boots successfully. | 1810 | <emphasis>Use a Working Configuration:</emphasis> |
| 1798 | This configuration file will be your baseline. | 1811 | Start with a full configuration that you |
| 1812 | know works. | ||
| 1813 | Be sure the configuration builds and boots | ||
| 1814 | successfully. | ||
| 1815 | Use this configuration file as your baseline. | ||
| 1799 | </para></listitem> | 1816 | </para></listitem> |
| 1800 | <listitem><para>Separately run the | 1817 | <listitem><para> |
| 1818 | <emphasis>Run Configure and Check Tasks:</emphasis> | ||
| 1819 | Separately run the | ||
| 1801 | <filename>do_kernel_configme</filename> and | 1820 | <filename>do_kernel_configme</filename> and |
| 1802 | <filename>do_kernel_configcheck</filename> tasks: | 1821 | <filename>do_kernel_configcheck</filename> tasks: |
| 1803 | <literallayout class='monospaced'> | 1822 | <literallayout class='monospaced'> |
| @@ -1805,7 +1824,9 @@ | |||
| 1805 | $ bitbake linux-yocto -c kernel_configcheck -f | 1824 | $ bitbake linux-yocto -c kernel_configcheck -f |
| 1806 | </literallayout> | 1825 | </literallayout> |
| 1807 | </para></listitem> | 1826 | </para></listitem> |
| 1808 | <listitem><para>Take the resulting list of files from the | 1827 | <listitem><para> |
| 1828 | <emphasis>Process the Results:</emphasis> | ||
| 1829 | Take the resulting list of files from the | ||
| 1809 | <filename>do_kernel_configcheck</filename> task | 1830 | <filename>do_kernel_configcheck</filename> task |
| 1810 | warnings and do the following: | 1831 | warnings and do the following: |
| 1811 | <itemizedlist> | 1832 | <itemizedlist> |
| @@ -1826,8 +1847,10 @@ | |||
| 1826 | <listitem><para> | 1847 | <listitem><para> |
| 1827 | Remove repeated and invalid options. | 1848 | Remove repeated and invalid options. |
| 1828 | </para></listitem> | 1849 | </para></listitem> |
| 1829 | </itemizedlist></para></listitem> | 1850 | </itemizedlist> |
| 1851 | </para></listitem> | ||
| 1830 | <listitem><para> | 1852 | <listitem><para> |
| 1853 | <emphasis>Re-Run Configure and Check Tasks:</emphasis> | ||
| 1831 | After you have worked through the output of the kernel | 1854 | After you have worked through the output of the kernel |
| 1832 | configuration audit, you can re-run the | 1855 | configuration audit, you can re-run the |
| 1833 | <filename>do_kernel_configme</filename> and | 1856 | <filename>do_kernel_configme</filename> and |
