Andrew Geissler | f034379 | 2020-11-18 10:42:21 -0600 | [diff] [blame] | 1 | .. SPDX-License-Identifier: CC-BY-SA-2.0-UK |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 2 | |
| 3 | ****************************************** |
| 4 | Yocto Project Profiling and Tracing Manual |
| 5 | ****************************************** |
| 6 | |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 7 | Introduction |
| 8 | ============ |
| 9 | |
Andrew Geissler | 615f2f1 | 2022-07-15 14:00:58 -0500 | [diff] [blame^] | 10 | Yocto bundles a number of tracing and profiling tools --- this 'HOWTO' |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 11 | describes their basic usage and shows by example how to make use of them |
| 12 | to examine application and system behavior. |
| 13 | |
| 14 | The tools presented are for the most part completely open-ended and have |
| 15 | quite good and/or extensive documentation of their own which can be used |
| 16 | to solve just about any problem you might come across in Linux. Each |
| 17 | section that describes a particular tool has links to that tool's |
| 18 | documentation and website. |
| 19 | |
| 20 | The purpose of this 'HOWTO' is to present a set of common and generally |
| 21 | useful tracing and profiling idioms along with their application (as |
| 22 | appropriate) to each tool, in the context of a general-purpose |
| 23 | 'drill-down' methodology that can be applied to solving a large number |
| 24 | (90%?) of problems. For help with more advanced usages and problems, |
| 25 | please see the documentation and/or websites listed for each tool. |
| 26 | |
| 27 | The final section of this 'HOWTO' is a collection of real-world examples |
| 28 | which we'll be continually adding to as we solve more problems using the |
Andrew Geissler | 615f2f1 | 2022-07-15 14:00:58 -0500 | [diff] [blame^] | 29 | tools --- feel free to add your own examples to the list! |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 30 | |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 31 | General Setup |
| 32 | ============= |
| 33 | |
| 34 | Most of the tools are available only in 'sdk' images or in images built |
| 35 | after adding 'tools-profile' to your local.conf. So, in order to be able |
| 36 | to access all of the tools described here, please first build and boot |
| 37 | an 'sdk' image e.g. :: |
| 38 | |
| 39 | $ bitbake core-image-sato-sdk |
| 40 | |
| 41 | or alternatively by adding 'tools-profile' to the EXTRA_IMAGE_FEATURES line in |
Andrew Geissler | c926e17 | 2021-05-07 16:11:35 -0500 | [diff] [blame] | 42 | your local.conf:: |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 43 | |
| 44 | EXTRA_IMAGE_FEATURES = "debug-tweaks tools-profile" |
| 45 | |
| 46 | If you use the 'tools-profile' method, you don't need to build an sdk image - |
Andrew Geissler | c926e17 | 2021-05-07 16:11:35 -0500 | [diff] [blame] | 47 | the tracing and profiling tools will be included in non-sdk images as well e.g.:: |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 48 | |
| 49 | $ bitbake core-image-sato |
| 50 | |
| 51 | .. note:: |
| 52 | |
| 53 | By default, the Yocto build system strips symbols from the binaries |
| 54 | it packages, which makes it difficult to use some of the tools. |
| 55 | |
| 56 | You can prevent that by setting the |
| 57 | :term:`INHIBIT_PACKAGE_STRIP` |
Andrew Geissler | c926e17 | 2021-05-07 16:11:35 -0500 | [diff] [blame] | 58 | variable to "1" in your ``local.conf`` when you build the image:: |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 59 | |
| 60 | INHIBIT_PACKAGE_STRIP = "1" |
| 61 | |
| 62 | The above setting will noticeably increase the size of your image. |
| 63 | |
| 64 | If you've already built a stripped image, you can generate debug |
| 65 | packages (xxx-dbg) which you can manually install as needed. |
| 66 | |
| 67 | To generate debug info for packages, you can add dbg-pkgs to |
Andrew Geissler | c926e17 | 2021-05-07 16:11:35 -0500 | [diff] [blame] | 68 | EXTRA_IMAGE_FEATURES in local.conf. For example:: |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 69 | |
| 70 | EXTRA_IMAGE_FEATURES = "debug-tweaks tools-profile dbg-pkgs" |
| 71 | |
| 72 | Additionally, in order to generate the right type of debuginfo, we also need to |
Andrew Geissler | c926e17 | 2021-05-07 16:11:35 -0500 | [diff] [blame] | 73 | set :term:`PACKAGE_DEBUG_SPLIT_STYLE` in the ``local.conf`` file:: |
Andrew Geissler | c9f7865 | 2020-09-18 14:11:35 -0500 | [diff] [blame] | 74 | |
| 75 | PACKAGE_DEBUG_SPLIT_STYLE = 'debug-file-directory' |