From ebca1b7847ff34213e6da71c79f00cb4b6b0757b Mon Sep 17 00:00:00 2001 From: "Robert P. J. Day" Date: Fri, 27 Jun 2014 07:50:56 +0300 Subject: bitbake-user-manual-execution.xml: Minor fixes. Collection of typo and grammar fixes from "Execution" chapter. Signed-off-by: Scott Rifenbark --- .../bitbake-user-manual-execution.xml | 62 +++++++++++++--------- 1 file changed, 38 insertions(+), 24 deletions(-) diff --git a/doc/bitbake-user-manual/bitbake-user-manual-execution.xml b/doc/bitbake-user-manual/bitbake-user-manual-execution.xml index 127c87a29..8b6e0b442 100644 --- a/doc/bitbake-user-manual/bitbake-user-manual-execution.xml +++ b/doc/bitbake-user-manual/bitbake-user-manual-execution.xml @@ -6,8 +6,8 @@ The primary purpose for running BitBake is to produce some kind - of output such as an image, a kernel, or a software development - kit. + of output such as a single installable package, a kernel, a software + development kit, or even a full, board-specific bootable Linux image. Of course, you can execute the bitbake command with options that cause it to execute single tasks, compile single recipe files, capture or clear data, or simply @@ -26,15 +26,27 @@ see "The BitBake Command" section. - + + + Prior to executing BitBake, you should take advantage of available + parallel thread execution on your build host by setting the + BB_NUMBER_THREADS + variable in your project's local.conf + configuration file. + - - Prior to executing BitBake, you should take advantage of parallel - thread execution by setting the - BB_NUMBER_THREADS - variable in your local.conf - configuration file. - + + A common way to determine this value for your build host is to run: + + $ grep processor /proc/cpuinfo + + and count the number of processors displayed. Note that the number of + processors will take into account hyper-threading, so that a quad-core + build host with hyper-threading will most likely show eight processors, + which is the value you would then assign to that variable. + + +
Parsing the Base Configuration Metadata @@ -42,7 +54,7 @@ The first thing BitBake does is parse base configuration metadata. - Base configuration metadata consists of the + Base configuration metadata consists of your project's bblayers.conf file to determine what layers BitBake needs to recognize, all necessary layer.conf files (one from each layer), @@ -71,10 +83,11 @@ and BBFILES. BBPATH is used to search for - configuration and class files under - conf/ and classes/ + configuration and class files under the + conf and classes directories, respectively. - BBFILES is used to find recipe files + BBFILES is used to locate both recipe + and recipe append files (.bb and .bbappend). If there is no bblayers.conf file, it is assumed the user has set the BBPATH @@ -82,7 +95,7 @@ - Next, the bitbake.conf file is searched + Next, the bitbake.conf file is located using the BBPATH variable that was just constructed. The bitbake.conf file may also include other @@ -117,15 +130,15 @@ optional conf/bblayers.conf configuration file. This file is expected to contain a BBLAYERS - variable that is a space delimited list of 'layer' directories. + variable that is a space-delimited list of 'layer' directories. Recall that if BitBake cannot find a bblayers.conf - file then it is assumed the user has set the BBPATH + file, then it is assumed the user has set the BBPATH and BBFILES variables directly in the environment. For each directory (layer) in this list, a conf/layer.conf - file is searched for and parsed with the + file is located and parsed with the LAYERDIR variable being set to the directory where the layer was found. The idea is these files automatically set up @@ -143,7 +156,7 @@ Only variable definitions and include directives are allowed - in .conf files. + in BitBake .conf files. Some variables directly influence BitBake's behavior. These variables might have been set from the environment depending on the environment variables previously @@ -166,7 +179,8 @@ Other classes that are specified in the configuration using the INHERIT variable are also included. - BitBake searches for class files in a "classes" subdirectory under + BitBake searches for class files in a + classes subdirectory under the paths in BBPATH in the same way as configuration files. @@ -189,7 +203,7 @@ If a recipe uses a closing curly brace within the function and the character has no leading spaces, BitBake produces a parsing error. - If you use a pair of curly brace in a shell function, the + If you use a pair of curly braces in a shell function, the closing curly brace must not be located at the start of the line without leading spaces. @@ -261,14 +275,14 @@ One common convention is to use the recipe filename to define pieces of metadata. For example, in bitbake.conf the recipe - name and version set + name and version are used to set the variables PN and PV: - PV = "${@bb.parse.BBHandler.vars_from_file(d.getVar('FILE'),d)[1] or '1.0'}" PN = "${@bb.parse.BBHandler.vars_from_file(d.getVar('FILE'),d)[0] or 'defaultpkgname'}" + PV = "${@bb.parse.BBHandler.vars_from_file(d.getVar('FILE'),d)[1] or '1.0'}" - In this example, a recipe called "something_1.2.3.bb" sets + In this example, a recipe called "something_1.2.3.bb" would set PN to "something" and PV to "1.2.3". -- cgit 1.2.3-korg