Auto merge of #1925 - JohnTitor:tweak-gha, r=JohnTitor

Tweak GHA config to reduce bors time

So, "bors time" with the current config is slow a bit (~ 1h30m). We could reduce this by separating style check and docs generation, tweaking `max-parallel`, let's try it out!

.github/workflows/bors.yml

@@ -79,8 +79,8 @@ jobs:
         run: LIBC_CI=1 sh ./ci/run.sh ${{ matrix.target }}
         shell: bash
 
-  style_and_docs:
-    name: Style and docs
+  style_check:
+    name: Style check
     runs-on: ubuntu-18.04
     strategy:
       fail-fast: true
@@ -93,16 +93,14 @@ jobs:
         run: sh ./ci/install-rust.sh
       - name: Check style
         run: sh ci/style.sh
-      - name: Generate documentation
-        run: LIBC_CI=1 sh ci/dox.sh
 
   docker_linux_tier2:
     name: Docker Linux Tier2
-    needs: [docker_linux_tier1, style_and_docs]
+    needs: [docker_linux_tier1, style_check]
     runs-on: ubuntu-18.04
     strategy:
       fail-fast: true
-      max-parallel: 10
+      max-parallel: 12
       matrix:
         target: [
           aarch64-linux-android,
@@ -149,7 +147,7 @@ jobs:
   # devkitpro's pacman needs to be connected from Docker.
   docker_switch:
     name: Docker Switch
-    needs: [docker_linux_tier1, style_and_docs]
+    needs: [docker_linux_tier1, style_check]
     runs-on: ubuntu-18.04
     strategy:
       fail-fast: true
@@ -171,7 +169,7 @@ jobs:
       OS: linux
     strategy:
       fail-fast: true
-      max-parallel: 4
+      max-parallel: 5
       matrix:
         toolchain: [
           stable,
@@ -201,7 +199,7 @@ jobs:
       OS: macos
     strategy:
       fail-fast: true
-      max-parallel: 3
+      max-parallel: 4
       matrix:
         toolchain: [
           stable,
@@ -257,6 +255,22 @@ jobs:
       - name: Check breaking changes
         run: sh ci/semver.sh macos
 
+  docs:
+    name: Generate documentation
+    runs-on: ubuntu-18.04
+    needs: docker_linux_tier2
+    strategy:
+      fail-fast: true
+    steps:
+      - uses: rust-lang/simpleinfra/github-actions/cancel-outdated-builds@master
+        with:
+          github_token: "${{ secrets.GITHUB_TOKEN }}"
+      - uses: actions/checkout@v2
+      - name: Setup Rust toolchain
+        run: sh ./ci/install-rust.sh
+      - name: Generate documentation
+        run: LIBC_CI=1 sh ci/dox.sh
+
   # These jobs doesn't actually test anything, but they're only used to tell
   # bors the build completed, as there is no practical way to detect when a
   # workflow is successful listening to webhooks only.
@@ -272,12 +286,13 @@ jobs:
       docker_linux_tier2,
       macos,
       windows,
-      style_and_docs,
+      style_check,
       docker_switch,
       build_channels_linux,
       build_channels_macos,
       semver_linux,
-      semver_macos
+      semver_macos,
+      docs,
     ]
 
     steps:
@@ -293,12 +308,13 @@ jobs:
       docker_linux_tier2,
       macos,
       windows,
-      style_and_docs,
+      style_check,
       docker_switch,
       build_channels_linux,
       build_channels_macos,
       semver_linux,
-      semver_macos
+      semver_macos,
+      docs,
     ]
 
     steps:

README.md

 # libc - Raw FFI bindings to platforms' system libraries
 
-[![Azure Status]][Azure] [![Cirrus CI Status]][Cirrus CI] [![Latest Version]][crates.io] [![Documentation]][docs.rs] ![License]
+[![GHA Status]][GitHub Actions] [![Cirrus CI Status]][Cirrus CI] [![Latest Version]][crates.io] [![Documentation]][docs.rs] ![License]
 
 `libc` provides all of the definitions necessary to easily interoperate with C
 code (or "C-like" code) on each of the platforms that Rust supports. This
@@ -94,8 +94,8 @@ Unless you explicitly state otherwise, any contribution intentionally submitted
 for inclusion in `libc` by you, as defined in the Apache-2.0 license, shall be
 dual licensed as above, without any additional terms or conditions.
 
-[Azure Status]: https://dev.azure.com/rust-lang2/libc/_apis/build/status/rust-lang.libc%20(1)?branchName=master
-[Azure]: https://dev.azure.com/rust-lang2/libc/_build/latest?definitionId=1&branchName=master
+[GitHub Actions]: https://github.com/rust-lang/libc/actions
+[GHA Status]: https://github.com/rust-lang/libc/workflows/CI/badge.svg
 [Cirrus CI]: https://cirrus-ci.com/github/rust-lang/libc
 [Cirrus CI Status]: https://api.cirrus-ci.com/github/rust-lang/libc.svg
 [crates.io]: https://crates.io/crates/libc