executor: add Pender, rework Cargo features.

This introduces a `Pender` struct with enum cases for thread-mode, interrupt-mode and
custom callback executors. This avoids calls through function pointers when using only
the thread or interrupt executors. Faster, and friendlier to `cargo-call-stack`.

`embassy-executor` now has `arch-xxx` Cargo features to select the arch and to enable
the builtin executors (thread and interrupt).

2 files changed, 2 insertions, 2 deletions

diff --git a/examples/stm32f4/Cargo.toml b/examples/stm32f4/Cargo.toml
index 7a7bab5bb..d967d8501 100644
--- a/examples/stm32f4/Cargo.toml
+++ b/examples/stm32f4/Cargo.toml
@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
-embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["defmt", "integrated-timers"] }
+embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers", "arch-cortex-m", "executor-thread", "executor-interrupt"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "unstable-traits", "defmt", "stm32f429zi", "unstable-pac", "memory-x", "time-driver-any", "exti"]  }
 embassy-usb = { version = "0.1.0", path = "../../embassy-usb", features = ["defmt"] }
diff --git a/examples/stm32f4/src/bin/multiprio.rs b/examples/stm32f4/src/bin/multiprio.rs
index 77df51ac7..5d010f799 100644
--- a/examples/stm32f4/src/bin/multiprio.rs
+++ b/examples/stm32f4/src/bin/multiprio.rs
@@ -62,7 +62,7 @@ use core::mem;
 use cortex_m::peripheral::NVIC;
 use cortex_m_rt::entry;
 use defmt::*;
-use embassy_stm32::executor::{Executor, InterruptExecutor};
+use embassy_executor::{Executor, InterruptExecutor};
 use embassy_stm32::interrupt;
 use embassy_stm32::pac::Interrupt;
 use embassy_time::{Duration, Instant, Timer};