[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# https://bazel.build/concepts/platforms-intro#cxx
# This forces Bazel's C++ rules use platforms to select toolchains instead of the default
# --crosstool_top, --compiler, etc.
build --incompatible_enable_cc_toolchain_resolution
# We do not want Bazel to detect any C++ toolchains on the local machine
# https://github.com/bazelbuild/bazel/blob/4ccc21f2f089971e5f4032397764a4be3549c40a/tools/cpp/cc_configure.bzl#L47
build --action_env=BAZEL_DO_NOT_DETECT_CPP_TOOLCHAIN=1
# We would like developers to not upload to the remote build cache, only the RBE workers themselves.
build --remote_upload_local_results=false
# This tells Bazel that the host platform can use the hermetic toolchain. This is a small lie until
# Windows support is added.
build --host_platform=//bazel/platform:host_with_hermetic_toolchain
# Register our toolchains. We do this here, and not in WORKSPACE.bazel because
# --extra_toolchains has priority over register_toolchains and we conditionally add some toolchains
# for RBE.
build --extra_toolchains=//toolchain:clang_linux_x64_toolchain
build --extra_toolchains=//toolchain:clang_mac_x64_toolchain
build --extra_toolchains=//toolchain:clang_mac_arm64_toolchain
# --platforms refers to the target for which we are compiling. By setting the target to be a
# platform which has our own custom constraint_setting and constraint_value
# (skia_hermetic_toolchain=use_hermetic_toolchain), this causes Bazel to resolve the toolchain
# to be our hermetic one because our hermetic toolchains have that same constraint set in their
# target_compatible_with list.
build:for_linux_x64 --platforms=//bazel/platform:linux_x64_hermetic
build:for_linux_x64_with_rbe --config=linux_rbe --platforms=//bazel/platform:linux_x64_hermetic
build:for_mac_arm64 --platforms=//bazel/platform:mac_arm64_hermetic
build:for_mac_x64 --platforms=//bazel/platform:mac_x64_hermetic
# some aliases using more common lingo
build:for_mac_m1 --config=for_mac_arm64
build:for_mac_intel --config=for_mac_x64
[infra] Add initial Bazel rules and files
These rules can be used to build our GMs on WASM+WebGL and
libskia.a with just the CPU backend (and most other features
turned off).
This can be done with the following commands:
- bazel build //modules/canvaskit:gm-bindings-wasm --gpu_backend=gl_backend --with_gl_standard=webgl_standard
- bazel build :skia-core --config clang
This pivots slightly from http://review.skia.org/463517
by using config_settings [1] instead of platforms for
the optional features that we control. This pivot was
suggested in [2]
We have BUILD.bazel files in many of the subdirectories
that specify filegroups for the appropriate files. In
an effort to make //BUILD.bazel more readable, it is
the responsibility of these subfolders to deal with
conditionally including certain .h or .cpp files.
This is done using select statements and config_settings
or platform constraints as necessary.
For example, src/gpu/BUILD.bazel will different private
filegroups for each of the supported gpu backends [3]
and a more-visible filegroup called "srcs" that has
the right selection of the private files to be used
for compilation.
An effort has been made to avoid using glob() in our
BUILD.bazel files. These file lists were made by using
`ls -1` and some regex to add in quotes. We might want
to make a helper script to assist with that, if necessary.
To specify which options we have, the settings in
//bazel/common_config_settings/BUILD.bazel have been
redesigned. They make use of a macro `string_flag_with_values`
that removes the boilerplate. Patchset 36 shows what the
file looks like w/o the macro.
The top level BUILD.bazel file will still need to use
some logic to handle defines, because local_defines is
a list of strings, not a list of labels [4].
Suggested Review Order:
- WORKSPACE.bazel to see the new dependencies on the
emsdk toolchain and bazel_skylib
- bazel/common_config_settings/* to see the few settings
defined (we have more to define, see BUILD.gn and
//gn/skia.gni for ideas)
- BUILD.bazel to see the "skia-core" cc_library rule.
See also "gms" and "tests"
- modules/canvaskit/BUILD.bazel to see the use of
the emscripten "wasm_cc_binary" rule, which depends
on the "skia-core", "gms", and "tests" rule. Note that
it only builds some of the gms as a proof of concept.
- The other BUILD.bazel files. Some of these are not
platform or feature dependent (e.g. pathops). Others
are (e.g. gpu).
- All other files.
[1] https://docs.bazel.build/versions/4.2.1/skylark/config.html#user-defined-build-settings
[2] https://github.com/emscripten-core/emsdk/pull/920
[3] In this CL, that's just the webgl one.
[4] https://docs.bazel.build/versions/main/be/c-cpp.html#cc_library.local_defines
Change-Id: Ieecf9c106d5e3a6ae97d13d66be06b4b3c207089
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/458637
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Owners-Override: Kevin Lubick <kjlubick@google.com>
2021-11-08 20:26:09 +00:00
# =============================================================================
# Alias to build configurations below. This makes configuring things from
# the command line easier.
2021-11-16 19:09:44 +00:00
build --flag_alias=fontmgr_factory=//bazel/common_config_settings:fontmgr_factory
[infra] Add initial Bazel rules and files
These rules can be used to build our GMs on WASM+WebGL and
libskia.a with just the CPU backend (and most other features
turned off).
This can be done with the following commands:
- bazel build //modules/canvaskit:gm-bindings-wasm --gpu_backend=gl_backend --with_gl_standard=webgl_standard
- bazel build :skia-core --config clang
This pivots slightly from http://review.skia.org/463517
by using config_settings [1] instead of platforms for
the optional features that we control. This pivot was
suggested in [2]
We have BUILD.bazel files in many of the subdirectories
that specify filegroups for the appropriate files. In
an effort to make //BUILD.bazel more readable, it is
the responsibility of these subfolders to deal with
conditionally including certain .h or .cpp files.
This is done using select statements and config_settings
or platform constraints as necessary.
For example, src/gpu/BUILD.bazel will different private
filegroups for each of the supported gpu backends [3]
and a more-visible filegroup called "srcs" that has
the right selection of the private files to be used
for compilation.
An effort has been made to avoid using glob() in our
BUILD.bazel files. These file lists were made by using
`ls -1` and some regex to add in quotes. We might want
to make a helper script to assist with that, if necessary.
To specify which options we have, the settings in
//bazel/common_config_settings/BUILD.bazel have been
redesigned. They make use of a macro `string_flag_with_values`
that removes the boilerplate. Patchset 36 shows what the
file looks like w/o the macro.
The top level BUILD.bazel file will still need to use
some logic to handle defines, because local_defines is
a list of strings, not a list of labels [4].
Suggested Review Order:
- WORKSPACE.bazel to see the new dependencies on the
emsdk toolchain and bazel_skylib
- bazel/common_config_settings/* to see the few settings
defined (we have more to define, see BUILD.gn and
//gn/skia.gni for ideas)
- BUILD.bazel to see the "skia-core" cc_library rule.
See also "gms" and "tests"
- modules/canvaskit/BUILD.bazel to see the use of
the emscripten "wasm_cc_binary" rule, which depends
on the "skia-core", "gms", and "tests" rule. Note that
it only builds some of the gms as a proof of concept.
- The other BUILD.bazel files. Some of these are not
platform or feature dependent (e.g. pathops). Others
are (e.g. gpu).
- All other files.
[1] https://docs.bazel.build/versions/4.2.1/skylark/config.html#user-defined-build-settings
[2] https://github.com/emscripten-core/emsdk/pull/920
[3] In this CL, that's just the webgl one.
[4] https://docs.bazel.build/versions/main/be/c-cpp.html#cc_library.local_defines
Change-Id: Ieecf9c106d5e3a6ae97d13d66be06b4b3c207089
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/458637
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Owners-Override: Kevin Lubick <kjlubick@google.com>
2021-11-08 20:26:09 +00:00
build --flag_alias=gpu_backend=//bazel/common_config_settings:gpu_backend
2021-11-17 13:05:57 +00:00
build --flag_alias=include_decoder=//bazel/common_config_settings:include_decoder
build --flag_alias=include_encoder=//bazel/common_config_settings:include_encoder
build --flag_alias=include_fontmgr=//bazel/common_config_settings:include_fontmgr
2021-11-30 20:59:32 +00:00
build --flag_alias=shaper_backend=//bazel/common_config_settings:shaper_backend
[infra] Add initial Bazel rules and files
These rules can be used to build our GMs on WASM+WebGL and
libskia.a with just the CPU backend (and most other features
turned off).
This can be done with the following commands:
- bazel build //modules/canvaskit:gm-bindings-wasm --gpu_backend=gl_backend --with_gl_standard=webgl_standard
- bazel build :skia-core --config clang
This pivots slightly from http://review.skia.org/463517
by using config_settings [1] instead of platforms for
the optional features that we control. This pivot was
suggested in [2]
We have BUILD.bazel files in many of the subdirectories
that specify filegroups for the appropriate files. In
an effort to make //BUILD.bazel more readable, it is
the responsibility of these subfolders to deal with
conditionally including certain .h or .cpp files.
This is done using select statements and config_settings
or platform constraints as necessary.
For example, src/gpu/BUILD.bazel will different private
filegroups for each of the supported gpu backends [3]
and a more-visible filegroup called "srcs" that has
the right selection of the private files to be used
for compilation.
An effort has been made to avoid using glob() in our
BUILD.bazel files. These file lists were made by using
`ls -1` and some regex to add in quotes. We might want
to make a helper script to assist with that, if necessary.
To specify which options we have, the settings in
//bazel/common_config_settings/BUILD.bazel have been
redesigned. They make use of a macro `string_flag_with_values`
that removes the boilerplate. Patchset 36 shows what the
file looks like w/o the macro.
The top level BUILD.bazel file will still need to use
some logic to handle defines, because local_defines is
a list of strings, not a list of labels [4].
Suggested Review Order:
- WORKSPACE.bazel to see the new dependencies on the
emsdk toolchain and bazel_skylib
- bazel/common_config_settings/* to see the few settings
defined (we have more to define, see BUILD.gn and
//gn/skia.gni for ideas)
- BUILD.bazel to see the "skia-core" cc_library rule.
See also "gms" and "tests"
- modules/canvaskit/BUILD.bazel to see the use of
the emscripten "wasm_cc_binary" rule, which depends
on the "skia-core", "gms", and "tests" rule. Note that
it only builds some of the gms as a proof of concept.
- The other BUILD.bazel files. Some of these are not
platform or feature dependent (e.g. pathops). Others
are (e.g. gpu).
- All other files.
[1] https://docs.bazel.build/versions/4.2.1/skylark/config.html#user-defined-build-settings
[2] https://github.com/emscripten-core/emsdk/pull/920
[3] In this CL, that's just the webgl one.
[4] https://docs.bazel.build/versions/main/be/c-cpp.html#cc_library.local_defines
Change-Id: Ieecf9c106d5e3a6ae97d13d66be06b4b3c207089
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/458637
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Owners-Override: Kevin Lubick <kjlubick@google.com>
2021-11-08 20:26:09 +00:00
build --flag_alias=with_gl_standard=//bazel/common_config_settings:with_gl_standard
2021-11-16 19:09:44 +00:00
2022-04-11 19:22:51 +00:00
build --flag_alias=disable_effect_serialization=no//bazel/common_config_settings:enable_effect_serialization
build --flag_alias=enable_effect_serialization=//bazel/common_config_settings:enable_effect_serialization
[bazel] Add in hierarchical filegroup Bazel rules.
The primary goal of this organization structure is to keep
our top level BUILD.bazel file short, with as little logic
as feasible. The logic required to control which files to
include, which third_party deps are needed, what system libraries
should be linked again, etc, should be in the BUILD.bazel
file best should be as close to the affected files as feasible.
In essence, we use filegroup() rules to bubble up the files
needed to build Skia (all as one big cc_library call) and
cc_library rules to bubble up the other components needed to build.
For example, //src/ports/SkFontHost_FreeType.cpp needs FreeType,
but only if we are compiling Skia with that type of font
support. With the new organization structure in this CL,
//src/ports/BUILD.bazel should have the logic that determines
if the cpp file should be included in the build of Skia and
if it is, that the Skia build should depend on //third_party:freetype2
Another example is //src/gpu/ganesh/BUILD.bazel, which
chooses which of the dawn, gl, vulkan, etc backend sources,
and the associated dependencies to include in the build.
It does not specify what those are, but delegates to the
BUILD.bazel files in the subdirectories housing the
backend-specific code.
The structure guidelines for BUILD.bazel files are as follows:
- Have a filegroup() called "hdrs" (for public headers) or
"srcs" (for private headers and all .cpp files) that is
visible to the parent directory. This should list the
files from the containing directory to include in the
build.
See //include/core/BUILD.bazel and //src/effects/BUILD.bazel
as examples.
- filegroup() rules can list a child directory's "hdrs"
or "srcs" in their "srcs" attributes, but should not contain
select statements pertaining to child directory files.
See //include/gpu/BUILD.bazel and //src/gpu/ganesh/BUILD.bazel
as examples.
- May have a cc_library() called "deps". This can specify
dependencies, cc_opts, and linkopts, but not srcs or hdrs. [1]
See //src/codec/BUILD.bazel as an example. These should
be visible to the parent directory.
- "hdrs", "srcs", and "deps" for the primary Skia build
(currently called "skia_core") should bubble up through
//include/BUILD.bazel and //src/BUILD.bazel, one directory
at a time.
This CL demonstrates a very basic build of Skia with many features
turned off (CPU only, no fonts, no codecs). Follow-on CLs will
add to these rules as more targets are supported. See bazel/Makefile
for the builds that work with just this CL.
Suggested Review Order:
- //BUILD.bazel to see the very small skia_core rule which
delegates all the logic down stack. Note that it has a
dependency on //bazel:defines_from_flags which will set
all the defines listed there when compiling all the
.cpp and .h files in skia_core *and* anything that depends
on skia_core, but *not* //src:deps.
- //include/BUILD.bazel and other BUILD.bazel files in the
subdirectories of that folder. Note that the filegroups in
//include/private/... are called "srcs" to be similar to
how Bazel wants "private headers" to be in the "srcs" of
cc_library, cc_binary, etc. and only public headers are
to be in "hdrs" [2].
- //src/BUILD.bazel and other BUILD.bazel files in the
subdirectories of that folder. //src/gpu/ganesh/...
will be filled in for dawn, vulkan, and GL in the next CL.
- //PRESUBMIT.py, which adds a check that runs buildifier [3]
on modified BUILD.bazel files to make sure they stay
consistently formatted.
- //bazel/... to see the new option I added to make sksl
opt-in or opt-out, so one could build Skia with sksl,
but not with a gpu backend.
- Misc .h and .cpp files, whose includes were removed if
unnecessary or #ifdef'd out to make the minimal build
work without GPU or SkSL includes.
- //bazel/Makefile to see the builds that work with this CL.
[1] Setting srcs or hdrs is error-prone at best, because those
files will be compiled with a different set of defines than
the rest of skia_core, because they wouldn't depend on
//bazel:defines_from_flags.
[2] https://bazel.build/reference/be/c-cpp#cc_library.hdrs
[3] https://github.com/bazelbuild/buildtools/releases
Change-Id: I5e0e3ae01ad42d672506d5aad1239f2512188191
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/543977
Reviewed-by: Leandro Lovisolo <lovisolo@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
2022-05-27 17:56:03 +00:00
build --flag_alias=disable_sksl=no//bazel/common_config_settings:enable_sksl
build --flag_alias=enable_sksl=//bazel/common_config_settings:enable_sksl
2022-04-11 19:22:51 +00:00
build --flag_alias=disable_skslc=no//bazel/common_config_settings:enable_skslc
build --flag_alias=enable_skslc=//bazel/common_config_settings:enable_skslc
2022-04-12 12:23:07 +00:00
build --flag_alias=disable_sksl_tracing=no//bazel/common_config_settings:enable_sksl_tracing
build --flag_alias=enable_sksl_tracing=//bazel/common_config_settings:enable_sksl_tracing
2022-06-27 14:07:26 +00:00
build --flag_alias=disable_svg_canvas=no//bazel/common_config_settings:enable_svg_canvas
build --flag_alias=enable_svg_canvas=//bazel/common_config_settings:enable_svg_canvas
2022-04-11 19:22:51 +00:00
build --flag_alias=disable_tracing=no//bazel/common_config_settings:enable_tracing
build --flag_alias=enable_tracing=//bazel/common_config_settings:enable_tracing
build --flag_alias=disable_vma=no//bazel/common_config_settings:use_vulkan_memory_allocator
build --flag_alias=enable_vma=//bazel/common_config_settings:use_vulkan_memory_allocator
2022-04-08 18:23:38 +00:00
build --flag_alias=with_icu=//bazel/common_config_settings:use_icu
build --flag_alias=with_no_icu=no//bazel/common_config_settings:use_icu
2022-04-11 17:41:47 +00:00
2021-11-16 19:09:44 +00:00
# CanvasKit flags
build --flag_alias=ck_enable_fonts=//modules/canvaskit:enable_fonts
2022-03-25 18:59:33 +00:00
build --flag_alias=ck_disable_fonts=no//modules/canvaskit:enable_fonts
# =============================================================================
# REMOTE BUILD EXECUTION
# =============================================================================
# =====
# The following was copied from https://github.com/bazelbuild/bazel-toolchains/blob/ea243d43269df23de03a797cff2347e1fc3d02bb/bazelrc/bazel-4.1.0.bazelrc
# We should be free to modify this as we see fit.
2022-03-28 13:45:26 +00:00
#
2022-03-25 18:59:33 +00:00
# Depending on how many machines are in the remote execution instance, setting
# this higher can make builds faster by allowing more jobs to run in parallel.
# Setting it too high can result in jobs that timeout, however, while waiting
# for a remote machine to execute them.
build:remote --jobs=50
# Set several flags related to specifying the platform, toolchain and java
# properties.
build:remote --java_runtime_version=rbe_jdk
build:remote --tool_java_runtime_version=rbe_jdk
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# When a remote configuration is chosen, add "remote" to the list of spawn_strategies.
build:remote --spawn_strategy=remote,sandboxed
2022-03-25 18:59:33 +00:00
# Enable remote execution so actions are performed on the remote systems.
build:remote --remote_executor=grpcs://remotebuildexecution.googleapis.com
# Enforce stricter environment rules, which eliminates some non-hermetic
# behavior and therefore improves both the remote cache hit rate and the
# correctness and repeatability of the build.
build:remote --incompatible_strict_action_env=true
2022-04-07 14:31:59 +00:00
# No compile task should take more than 180 seconds. Really long running tasks
# are probably a result of spinning up new workers.
build:remote --remote_timeout=180
2022-03-25 18:59:33 +00:00
# Enable authentication. This will pick up application default credentials by
# default. You can use --google_credentials=some_file.json to use a service
# account credential instead.
# See https://developers.google.com/remote-build-execution/docs/authentication
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# To authenticate, you should run gcloud auth application-default login
2022-03-25 18:59:33 +00:00
build:remote --google_default_credentials=true
# End of the copied RBE settings
#=====
# Use the RBE instance on the skia-rbe GCP project.
build:remote --remote_instance_name projects/skia-rbe/instances/default_instance
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# The linxu_rbe config will build on RBE and default to compiling for linux_x64 using
# the hermetic toolchain.
[infra] Add BazelBuild task to build CanvasKit on the CI with Bazel
For additional context, see "Codifying Certain Build Options"
and "Building on the CI" in the design doc go/skia-bazel
Suggested review order:
- builder_name_schema.json to see the three required and
one optional part of BazelBuild jobs.
- jobs.json to see one new BazelBuild job added. In an
ideal world, this job would have been named
BazelBuild-//modules/canvaskit:canvaskit_wasm-debug-linux_x64
but Buildbucket (?) requires jobs match the regex
^[a-zA-Z0-9\\-_.\\(\\) ]{1,128}$
so we use spaces instead of slashes or colons.
- gen_tasks_logic.go; noting the makeBazelLabel function
expands most of the spaces to / and the last one to a
colon to make a single-target label. If there are three
dots, then it is a multi-target label, and we do not
need to add a colon.
- bazel_build.go; This is a very simple task driver, and
I do not anticipate getting too much more complex.
The place where we decide which args to augment
a build with depend on the host platform and thus
should be set in gen_tasks_logic.go.
- bazel/buildrc to see some initial configurations set,
one of which, "debug", is used by the new job.
The "release" version of CanvasKit probably works on
3.1.10 which had a bugfix, but we are still on
3.1.9
- .bazelrc to see a rename of the linux-rbe config to
linux_rbe (our configs should have no dashes if
we want to specify them verbatim in our Job names).
It also imports the Skia-specified build configs
from //bazel/buildrc and supports the user-specified
//bazel/user/buildrc file if it exists.
- All other files in any order.
Change-Id: Ib954dd6045100eadcbbf4ffee0888f6fbce65fa7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/537797
Reviewed-by: Eric Boren <borenet@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-05-06 17:20:12 +00:00
build:linux_rbe --config=remote
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# On the RBE instances, we also have the Java and C++ toolchain from the Docker image available.
# These need to come after the --extra_toolchains flags (above) that register our hermetic
# toolchains, because we only want these backup toolchains to be used by Bazel internals,
# if at all.
[infra] Add BazelBuild task to build CanvasKit on the CI with Bazel
For additional context, see "Codifying Certain Build Options"
and "Building on the CI" in the design doc go/skia-bazel
Suggested review order:
- builder_name_schema.json to see the three required and
one optional part of BazelBuild jobs.
- jobs.json to see one new BazelBuild job added. In an
ideal world, this job would have been named
BazelBuild-//modules/canvaskit:canvaskit_wasm-debug-linux_x64
but Buildbucket (?) requires jobs match the regex
^[a-zA-Z0-9\\-_.\\(\\) ]{1,128}$
so we use spaces instead of slashes or colons.
- gen_tasks_logic.go; noting the makeBazelLabel function
expands most of the spaces to / and the last one to a
colon to make a single-target label. If there are three
dots, then it is a multi-target label, and we do not
need to add a colon.
- bazel_build.go; This is a very simple task driver, and
I do not anticipate getting too much more complex.
The place where we decide which args to augment
a build with depend on the host platform and thus
should be set in gen_tasks_logic.go.
- bazel/buildrc to see some initial configurations set,
one of which, "debug", is used by the new job.
The "release" version of CanvasKit probably works on
3.1.10 which had a bugfix, but we are still on
3.1.9
- .bazelrc to see a rename of the linux-rbe config to
linux_rbe (our configs should have no dashes if
we want to specify them verbatim in our Job names).
It also imports the Skia-specified build configs
from //bazel/buildrc and supports the user-specified
//bazel/user/buildrc file if it exists.
- All other files in any order.
Change-Id: Ib954dd6045100eadcbbf4ffee0888f6fbce65fa7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/537797
Reviewed-by: Eric Boren <borenet@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-05-06 17:20:12 +00:00
build:linux_rbe --extra_toolchains=//bazel/rbe/gce_linux/java:all
build:linux_rbe --extra_toolchains=//bazel/rbe/gce_linux/config:cc-toolchain
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
# Make the RBE platform available for selection as an Execution platform.
build:linux_rbe --extra_execution_platforms=//bazel/rbe:gce_linux_platform
[infra] Add BazelBuild task to build CanvasKit on the CI with Bazel
For additional context, see "Codifying Certain Build Options"
and "Building on the CI" in the design doc go/skia-bazel
Suggested review order:
- builder_name_schema.json to see the three required and
one optional part of BazelBuild jobs.
- jobs.json to see one new BazelBuild job added. In an
ideal world, this job would have been named
BazelBuild-//modules/canvaskit:canvaskit_wasm-debug-linux_x64
but Buildbucket (?) requires jobs match the regex
^[a-zA-Z0-9\\-_.\\(\\) ]{1,128}$
so we use spaces instead of slashes or colons.
- gen_tasks_logic.go; noting the makeBazelLabel function
expands most of the spaces to / and the last one to a
colon to make a single-target label. If there are three
dots, then it is a multi-target label, and we do not
need to add a colon.
- bazel_build.go; This is a very simple task driver, and
I do not anticipate getting too much more complex.
The place where we decide which args to augment
a build with depend on the host platform and thus
should be set in gen_tasks_logic.go.
- bazel/buildrc to see some initial configurations set,
one of which, "debug", is used by the new job.
The "release" version of CanvasKit probably works on
3.1.10 which had a bugfix, but we are still on
3.1.9
- .bazelrc to see a rename of the linux-rbe config to
linux_rbe (our configs should have no dashes if
we want to specify them verbatim in our Job names).
It also imports the Skia-specified build configs
from //bazel/buildrc and supports the user-specified
//bazel/user/buildrc file if it exists.
- All other files in any order.
Change-Id: Ib954dd6045100eadcbbf4ffee0888f6fbce65fa7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/537797
Reviewed-by: Eric Boren <borenet@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-05-06 17:20:12 +00:00
# Import our specified build configurations
# https://docs.bazel.build/versions/main/best-practices.html#using-the-bazelrc-file
# We chose to split our build configurations into their own file to have better organization
# because we anticipate that file growing large.
import %workspace%/bazel/buildrc
# Import User's custom builds if they have defined any
[bazel] Add support for Macs to make Linux RBE builds
The big change here is having the C++ toolchain use
Bazel platforms instead of the C++ specific flags/setup.
In Bazel, platforms are a general purpose way to define
things like os, cpu architecture, etc. We were not using
platforms previously, because the best documentation at
the time focused on the old ways.
However, the old ways were clumsy/difficult when trying
to manage cross-compilation, specifically when trying
to have a Mac host trigger a build on our Linux RBE
system targeting a Linux x64 system. Thus, rather than
keep investing in the legacy system, this CL migrates
us to using platforms where possible.
Suggested background reading to better understand this CL:
- https://bazel.build/concepts/platforms-intro
- https://bazel.build/docs/platforms
- https://bazel.build/docs/toolchains#registering-building-toolchains
The hermetic toolchain itself is not changing in this CL
(and likely does not need to), only how we tell Bazel
about it (i.e. registering it) and how Bazel decides
to use it (i.e. resolving toolchains).
Here is my understanding of how platforms and toolchains
interact (supported by some evidence from [1][2])
- Bazel needs to resolve platforms for the Host, Execution,
and Target.
- If not specified via flags, these are the machine from
which Bazel is invoked, aka "@local_config_platform//:host".
- With this CL, the Host could be a Mac laptop, the Execution
platform is our Linux RBE pool, and the Target is "a Linux
system with a x64 CPU"
- To specify the Host, that is, describe to Bazel the
capabilities of the system it is running on, one can
set --host_platform [3] with a label pointing to a platform()
containing the appropriate settings. Tip: have this
platform inherit from @local_config_platform//:host
so it can add to any of the constraint_settings and
constraint_values that Bazel deduces automatically.
- To specify the Target platform(s), that is, the system
on which a final output resides and can execute, one
can set the --platforms flag with a label referencing
a platform().
- Bazel will then choose an execution platform to fulfill
that request. Bazel will look through a list of available
platforms, which can be augmented* with the
--extra_execution_platforms. Platforms specified by this
flag will be considered higher than the default platforms!
- Having selected the appropriate platforms, Bazel now
needs to select a toolchain to actually run the actions
of the appropriate type.
- Bazel looks through the list of available toolchains
and finds one that "matches" the Execution and the Target
platform. This means, the toolchain's exec_compatible_with
is a strict subset of the Execution platform and
the toolchain's target_compatible_with is a strict subset
of the Target platform. To register toolchains* (i.e. add
them to the resolution list), we use --extra_toolchains.
Once Bazel finds a match, it stops looking.
Using --toolchain_resolution_debug=".*" makes Bazel log
how it is resolving these toolchains and what execution
platform it picked.
* We can also register execution platforms and toolchains in
WORKSPACE.bazel [4], but the flags come with higher priority
and that made resolution a bit tricky. Also, when we want
to conditionally add them (e.g. --config=linux_rbe), we
cannot remove them conditionally in the WORKSPACE.bazel file.
The above resolution flow directly necessitated the changes
in this CL.
Example usage of the new configs and platforms:
# Can be run on a x64 Linux host and uses the hermetic toolchain.
bazel build //:skia_public
# Can be run on Mac or Linux and uses the Linux RBE system along
# with the hermetic toolchain to compile a binary for Linux x64.
bazel build //:skia_public --config=linux_rbe --config=for_linux_x64
# Shorthand for above
bazel build //:skia_public --config=for_linux_x64_with_rbe
Notice we don't have to type out --config=clang_linux anymore!
That was due to me reading the Bazel docs more carefully and
realizing we can set options for *all* Bazel build commands.
Current Limitations:
- Targets which require a py_binary (e.g. Dawn's genrules)
will not work on RBE when cross compiling because the
python runtime we download is for the host machine, not
the executor. This means //example:hello_world_dawn does
not work on Mac when cross-compiling via linux_rbe.
- Mac M1 linking not quite working with SkOpts settings.
Probably need to set -target [5]
Suggested Review order:
- toolchain/BUILD.bazel Notice how we do away with
cc_toolchain_suite for toolchain. These have the same
role: giving Bazel the information about where a toolchain
can run. The platforms one is more expressive (IMO), allowing
us to say both where to run the toolchain and what it can
make. In order to more easily force the use of our hermetic
toolchain, but also allow the hermetic toolchain to be used
on RBE, we specify "use_hermetic_toolchain" only on the target,
because the RBE image does not have the hermetic toolchain
on it by default (but can certainly run it).
- bazel/platform/BUILD.bazel to see the custom constraint_setting
and corresponding constraint_value. The names for both of these
are completely arbitrary - they do not need to have any deeper
meaning or relation to any file or Docker image or system or
any other constraints. Think of the constraint_setting as
an Enum and the constraint_value being the one and only member.
We need to pass around a constant value, not a type, so we
need to provide the constraint_value (e.g. in toolchain/BUILD.bazel)
but not a constraint_setting. However we need a
constraint_setting declared so we can make a constraint_value
of that "type".
Notice the platform declared here - it allows us to force
Bazel to use the hermetic toolchain because of the extra
constraint_value.
- .bazelrc I set a few flags that will be on for all
bazel build commands. Importantly, this causes the C++
build logic to use platforms and not the old, bespoke way.
I also found a way to avoid using the local toolchain on
the host, which will hopefully lead to clearer errors
if platforms are mis-specified instead of odd compile
errors because the host toolchain is too old or something.
There are also a few RBE settings tweaked to be a bit
more modern, as well the new shorthands for specifying
target platforms (e.g. for_linux_x64).
- bazel/buildrc where we have to turn off the platforms
logic for emscripten https://github.com/emscripten-core/emsdk/issues/984
- bazel/rbe/BUILD.bazel for a fix in the platform description
that makes it work on Mac.
- Notice that _m1 has been removed from the mac-related toolchain
files because the same toolchain should work on both
architectures.
- All other changes in any order.
[1] https://bazel.build/docs/toolchains#debugging-toolchains
[2] https://bazel.build/docs/toolchains#toolchain-resolution
[3] https://bazel.build/reference/command-line-reference
[4] https://bazel.build/docs/toolchains#registering-building-toolchains
[5] https://github.com/google/skia/blob/17dc3f16fc78477503ba1ef484c3b47bc3aab893/gn/skia/BUILD.gn#L258-L271
Change-Id: I515c114099d659639a808f74e47d489a68b7af62
Bug: skia:12541
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/549737
Reviewed-by: Erik Rose <erikrose@google.com>
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
2022-06-22 19:28:10 +00:00
try-import %workspace%/bazel/user/buildrc
