On 08/21/2012 01:11 AM, Liu wrote:
Hi all,
In order to learn to use poky,I am wondering how bitbake works with so many
recipes. When I bitbake <target>, I want to know how bitbake collect the
providers of <target> . Then bitbake will prepare the runqueue tasks to build
the <target>.So I need to know which tasks to assign to build the <target>.And
bitbake run these tasks in what order.In other words according to the
characteristics of what to decided to implement which task first and then next.
I am very eager to know the answers.
I'm not an expert, but here's some information that I believe is correct.
(If someone else knows better, please correct this...)
bitbake reads the entire set of recipe files that are specified by
the local configuration, and parses them all into a global task namespace.
This includes all the class files and include files as well. These
are specified by the BBFILES and BBLAYERS variables in the conf/bblayers.conf
file. Within the layers directories, the <layer-dir>/conf/layer.conf
file is used to indicate the set of .bb files to parse for that layer.
Note that this global parse of the entire set of recipe files is
quite different from 'make', which usually operated on a single Makefile.
(This is also why bitbake startup is a little slow).
Information in the meta-data (the DEPENDS and PROVIDES lines) determine
package ordering. Where packages are independent of each other, the
build order is dependent (I believe) on file parse order. In this case,
processing is not required to be in any particular order (and, in fact,
can be parallelized). You can have bitbake produce the dependency graph
of the packages for your build by using the -g option. This produces output in
'dot' syntax (suitable for processing using some graphviz visualizer).
The list of tasks to perform within a package appears to come
from the common class meta-data
(see meta/classes/utility-tasks.bbclass, for example) and the
meta-data for the individual package These are added by
the 'addtask' keyword. You can see a list of tasks for an
individual package with: bitbake <pkg> -c listtasks
I have started to put together an overview introduction of Yocto at:
http://elinux.org/Yocto_Project_IntroductionI haven't gotten much completed yet, but I do discuss bitbake there
a bit. Hopefully what I've got so far will be helpful.
-- Tim
P.S. someone correct me if I'm wrong.
Thanks ,
------ Yu Liu
Following is the some output of bitbake busybox and in this example I want
to know why first do the task of (quilt-native_0.51.bb, do_fetch) :
Parsing recipes...done.
Parsing of 830 .bb files complete (0 cached, 830 parsed). 1106 targets, 34
skipped, 0 masked, 0 errors.
OE Build Configuration:
BB_VERSION = "1.15.2"
TARGET_ARCH = "arm"
TARGET_OS = "linux-gnueabi"
MACHINE = "qemuarm"
DISTRO = "poky"
DISTRO_VERSION = "1.2.1"
TUNE_FEATURES = "armv5 dsp thumb arm926ejs"
TARGET_FPU = "soft"
meta
meta-yocto = "<unknown>:<unknown>"
NOTE: Resolving any missing task queue dependencies
NOTE: multiple providers are available for virtual/arm-none-linux-gnueabi-g++
(external-csl-toolchain, gcc-cross)
NOTE: consider defining a PREFERRED_PROVIDER entry to match
virtual/arm-none-linux-gnueabi-g++
NOTE: multiple providers are available for runtime linux-libc-headers-dev
(linux-libc-headers, linux-libc-headers-yocto, linux-libc-headers-yocto-nativesdk)
NOTE: consider defining a PREFERRED_PROVIDER entry to match linux-libc-headers-dev
NOTE: Preparing runqueue
NOTE: Executing SetScene Tasks
NOTE: Executing RunQueue Tasks
NOTE: Running task 1 of 706 (ID: 18,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/quilt/quilt-native_0.51.bb,
do_fetch)
NOTE: Running task 2 of 706 (ID: 228,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/gnu-config/gnu-config_20111111.bb,
do_fetch)
NOTE: Running task 3 of 706 (ID: 189,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/autoconf/autoconf_2.68.bb,
do_fetch)
NOTE: Running task 4 of 706 (ID: 515,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/m4/m4-native_1.4.16.bb,
do_fetch)
NOTE: package gnu-config-native-20111111-r1: task do_fetch: Started
NOTE: package m4-native-1.4.16-r2: task do_fetch: Started
NOTE: package quilt-native-0.51-r1: task do_fetch: Started
NOTE: package autoconf-native-2.68-r7: task do_fetch: Started
NOTE: package gnu-config-native-20111111-r1: task do_fetch: Succeeded
NOTE: Running task 5 of 706 (ID: 224,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/gnu-config/gnu-config_20111111.bb,
do_unpack)
NOTE: package gnu-config-native-20111111-r1: task do_unpack: Started
NOTE: package gnu-config-native-20111111-r1: task do_unpack: Succeeded
NOTE: Running task 6 of 706 (ID: 202,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/automake/automake_1.11.2.bb,
do_fetch)
NOTE: package automake-native-1.11.2-r3: task do_fetch: Started
NOTE: package m4-native-1.4.16-r2: task do_fetch: Succeeded
NOTE: Running task 7 of 706 (ID: 511,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/m4/m4-native_1.4.16.bb,
do_unpack)
NOTE: package m4-native-1.4.16-r2: task do_unpack: Started
NOTE: package m4-native-1.4.16-r2: task do_unpack: Succeeded
NOTE: Running task 8 of 706 (ID: 215,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/libtool/libtool-native_2.4.2.bb,
do_fetch)
NOTE: package autoconf-native-2.68-r7: task do_fetch: Succeeded
NOTE: Running task 9 of 706 (ID: 185,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/autoconf/autoconf_2.68.bb,
do_unpack)
NOTE: package libtool-native-2.4.2-r2.0: task do_fetch: Started
NOTE: package autoconf-native-2.68-r7: task do_unpack: Started
NOTE: package autoconf-native-2.68-r7: task do_unpack: Succeeded
NOTE: Running task 10 of 706 (ID: 254,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/zlib/zlib_1.2.6.bb,
do_fetch)
NOTE: package automake-native-1.11.2-r3: task do_fetch: Succeeded
NOTE: Running task 11 of 706 (ID: 198,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/automake/automake_1.11.2.bb,
do_unpack)
NOTE: package zlib-native-1.2.6-r1: task do_fetch: Started
NOTE: package automake-native-1.11.2-r3: task do_unpack: Started
NOTE: package automake-native-1.11.2-r3: task do_unpack: Succeeded
NOTE: Running task 12 of 706 (ID: 450,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/pkgconfig/pkgconfig_0.25.bb,
do_fetch)
NOTE: package pkgconfig-native-0.25-r3: task do_fetch: Started
WARNING: Failed to fetch URL http://www.zlib.net/zlib-1.2.6.tar.bz2
NOTE: package zlib-native-1.2.6-r1: task do_fetch: Succeeded
NOTE: Running task 13 of 706 (ID: 250,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/zlib/zlib_1.2.6.bb,
do_unpack)
NOTE: package zlib-native-1.2.6-r1: task do_unpack: Started
NOTE: package pkgconfig-native-0.25-r3: task do_fetch: Succeeded
NOTE: Running task 14 of 706 (ID: 446,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/pkgconfig/pkgconfig_0.25.bb,
do_unpack)
NOTE: package zlib-native-1.2.6-r1: task do_unpack: Succeeded
NOTE: Running task 15 of 706 (ID: 241,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/gettext/gettext-minimal-native_0.18.1.1.bb,
do_fetch)
NOTE: package gettext-minimal-native-0.18.1.1-r3: task do_fetch: Started
NOTE: package gettext-minimal-native-0.18.1.1-r3: task do_fetch: Succeeded
NOTE: Running task 16 of 706 (ID: 237,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/gettext/gettext-minimal-native_0.18.1.1.bb,
do_unpack)
NOTE: package pkgconfig-native-0.25-r3: task do_unpack: Started
NOTE: package pkgconfig-native-0.25-r3: task do_unpack: Succeeded
NOTE: Running task 17 of 706 (ID: 463,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/ncurses/ncurses_5.9.bb,
do_fetch)
NOTE: package gettext-minimal-native-0.18.1.1-r3: task do_unpack: Started
NOTE: package gettext-minimal-native-0.18.1.1-r3: task do_unpack: Succeeded
NOTE: Running task 18 of 706 (ID: 528,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-connectivity/openssl/ocf-linux_20100325.bb,
do_fetch)
NOTE: package ncurses-native-5.9-r9.1: task do_fetch: Started
NOTE: package ocf-linux-native-20100325-r3.0: task do_fetch: Started
NOTE: package libtool-native-2.4.2-r2.0: task do_fetch: Succeeded
NOTE: Running task 19 of 706 (ID: 211,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/libtool/libtool-native_2.4.2.bb,
do_unpack)
NOTE: package libtool-native-2.4.2-r2.0: task do_unpack: Started
NOTE: package libtool-native-2.4.2-r2.0: task do_unpack: Succeeded
NOTE: Running task 20 of 706 (ID: 280,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-connectivity/openssl/openssl_1.0.0i.bb,
do_fetch)
NOTE: package openssl-native-1.0.0i-r0.2: task do_fetch: Started
NOTE: package ncurses-native-5.9-r9.1: task do_fetch: Succeeded
NOTE: Running task 21 of 706 (ID: 459,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-core/ncurses/ncurses_5.9.bb,
do_unpack)
NOTE: package ncurses-native-5.9-r9.1: task do_unpack: Started
NOTE: package ncurses-native-5.9-r9.1: task do_unpack: Succeeded
NOTE: Running task 22 of 706 (ID: 176,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-support/sqlite/sqlite3_3.7.10.bb,
do_fetch)
NOTE: package sqlite3-native-3.7.10-r2: task do_fetch: Started
WARNING: Failed to fetch URL
http://download.savannah.gnu.org/releases/quilt/quilt-0.51.tar.gz
NOTE: package openssl-native-1.0.0i-r0.2: task do_fetch: Succeeded
NOTE: Running task 23 of 706 (ID: 276,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-connectivity/openssl/openssl_1.0.0i.bb,
do_unpack)
NOTE: package openssl-native-1.0.0i-r0.2: task do_unpack: Started
NOTE: package quilt-native-0.51-r1: task do_fetch: Succeeded
NOTE: Running task 24 of 706 (ID: 14,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/quilt/quilt-native_0.51.bb,
do_unpack)
NOTE: package openssl-native-1.0.0i-r0.2: task do_unpack: Succeeded
NOTE: Running task 25 of 706 (ID: 541,
virtual:native:/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-extended/pigz/pigz_2.2.4.bb,
do_fetch)
NOTE: package quilt-native-0.51-r1: task do_unpack: Started
NOTE: package quilt-native-0.51-r1: task do_unpack: Succeeded
NOTE: Running task 26 of 706 (ID: 15,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/quilt/quilt-native_0.51.bb,
do_patch)
NOTE: package pigz-native-2.2.4-r2: task do_fetch: Started
NOTE: package quilt-native-0.51-r1: task do_patch: Started
NOTE: package quilt-native-0.51-r1: task do_patch: Succeeded
NOTE: Running task 27 of 706 (ID: 20,
/home/ly/yocto/poky-denzil-7.0.1/meta/recipes-devtools/quilt/quilt-native_0.51.bb,
do_configure)
NOTE: package quilt-native-0.51-r1: task do_configure: Started
--
=============================
Tim Bird
Architecture Group Chair, CE Workgroup of the Linux Foundation
Senior Staff Engineer, Sony Network Entertainment
=============================
