diff --git a/.cirrus.yml b/.cirrus.yml
index ed54d2943b0..b0d8e10585a 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -10,10 +10,11 @@ task:
   env:
     LOOM_MAX_PREEMPTIONS: 2
     RUSTFLAGS: -Dwarnings
+    RUST_TOOLCHAIN: 1.56.0
   setup_script:
     - pkg install -y bash curl
     - curl https://sh.rustup.rs -sSf --output rustup.sh
-    - sh rustup.sh -y --profile minimal --default-toolchain stable
+    - sh rustup.sh -y --profile minimal --default-toolchain $RUST_TOOLCHAIN
     - . $HOME/.cargo/env
     - rustup target add i686-unknown-freebsd
     - |
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6bfb3b72704..aca605dedfc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -9,8 +9,10 @@ name: CI
 env:
   RUSTFLAGS: -Dwarnings
   RUST_BACKTRACE: 1
-  nightly: nightly-2021-04-25
-  minrust: 1.45.2
+  rust_stable: 1.56.0
+  rust_nightly: nightly-2021-04-25
+  rust_clippy: 1.52.0
+  rust_min: 1.45.2
 
 jobs:
   # Depends on all action sthat are required for a "successful" CI run.
@@ -43,6 +45,11 @@ jobs:
           - macos-latest
     steps:
       - uses: actions/checkout@v2
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: ${{ env.rust_stable }}
+            override: true
       - name: Install Rust
         run: rustup update stable
       - name: Install cargo-hack
@@ -80,8 +87,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Install Rust
-        run: rustup update stable
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: ${{ env.rust_stable }}
+            override: true
 
       - name: Install Valgrind
         run: |
@@ -117,9 +127,11 @@ jobs:
           - macos-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Install Rust
-        run: rustup update stable
-
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
+        with:
+            toolchain: ${{ env.rust_stable }}
+            override: true
       # Run `tokio` with "unstable" cfg flag.
       - name: test tokio full --cfg unstable
         run: cargo test --all-features
@@ -132,29 +144,28 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_nightly }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.nightly }}
-          override: true
-      - name: Install Miri
+            toolchain: ${{ env.rust_nightly }}
+            override: true
+            components: miri
+      - name: miri
         run: |
           set -e
-          rustup component add miri
-          cargo miri setup
-          rm -rf tokio/tests
-
-      - name: miri
-        run: cargo miri test --features rt,rt-multi-thread,sync task
+          rm -rf tests
+          cargo miri test --features rt,rt-multi-thread,sync task
         working-directory: tokio
   san:
     name: san
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_nightly }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.nightly }}
-          override: true
+            toolchain: ${{ env.rust_nightly }}
+            override: true
       - name: asan
         run: cargo test --all-features --target x86_64-unknown-linux-gnu --lib -- --test-threads 1
         working-directory: tokio
@@ -175,9 +186,10 @@ jobs:
           - arm-linux-androideabi
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: stable
+          toolchain: ${{ env.rust_stable }}
           target: ${{ matrix.target }}
           override: true
       - uses: actions-rs/cargo@v1
@@ -191,16 +203,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_nightly }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.nightly }}
+          toolchain: ${{ env.rust_nightly }}
+          target: ${{ matrix.target }}
           override: true
       - name: Install cargo-hack
         run: cargo install cargo-hack
-
       - name: check --each-feature
         run: cargo hack check --all --each-feature -Z avoid-dev-deps
-
       # Try with unstable feature flags
       - name: check --each-feature --unstable
         run: cargo hack check --all --each-feature -Z avoid-dev-deps
@@ -212,11 +224,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_min }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.minrust }}
+          toolchain: ${{ env.rust_min }}
           override: true
-
       - name: "test --workspace --all-features"
         run: cargo check --workspace --all-features
 
@@ -225,9 +237,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_nightly }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.nightly }}
+          toolchain: ${{ env.rust_nightly }}
           override: true
       - name: Install cargo-hack
         run: cargo install cargo-hack
@@ -245,11 +258,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Install Rust
-        run: rustup update stable
-      - name: Install rustfmt
-        run: rustup component add rustfmt
-
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: ${{ env.rust_stable }}
+          override: true
+          components: rustfmt
       # Check fmt
       - name: "rustfmt --check"
         # Workaround for rust-lang/cargo#7732
@@ -264,10 +278,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - name: Install Rust
-        run: rustup update 1.52.1 && rustup default 1.52.1
-      - name: Install clippy
-        run: rustup component add clippy
+      - name: Install Rust ${{ env.rust_clippy }}
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: ${{ env.rust_clippy }}
+          override: true
+          components: clippy
 
       # Run clippy
       - name: "clippy --all"
@@ -278,11 +294,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/toolchain@v1
+      - name: Install Rust ${{ env.rust_nightly }}
+        uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.nightly }}
+          toolchain: ${{ env.rust_nightly }}
           override: true
-
       - name: "doc --lib --all-features"
         run: cargo doc --lib --no-deps --all-features --document-private-items
         env:
@@ -302,9 +318,11 @@ jobs:
           - time::driver
     steps:
       - uses: actions/checkout@v2
-      - name: Install Rust
-        run: rustup update stable
-
+      - name: Install Rust ${{ env.rust_stable }}
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: ${{ env.rust_stable }}
+          override: true
       - name: loom ${{ matrix.scope }}
         run: cargo test --lib --release --features full -- --nocapture $SCOPE
         working-directory: tokio