From 89632f9b22d33bef08b2f98554e263c8a1d7cfa0 Mon Sep 17 00:00:00 2001 From: Per Lindgren Date: Wed, 1 Feb 2023 19:46:58 +0100 Subject: book polish --- book/en/src/by-example/tips_indirection.md | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-) (limited to 'book/en/src/by-example/tips_indirection.md') diff --git a/book/en/src/by-example/tips_indirection.md b/book/en/src/by-example/tips_indirection.md index 567a5e7..0de14a6 100644 --- a/book/en/src/by-example/tips_indirection.md +++ b/book/en/src/by-example/tips_indirection.md @@ -1,31 +1,26 @@ # Using indirection for faster message passing -Message passing always involves copying the payload from the sender into a -static variable and then from the static variable into the receiver. Thus -sending a large buffer, like a `[u8; 128]`, as a message involves two expensive +Message passing always involves copying the payload from the sender into a static variable and then from the static variable into the receiver. Thus sending a large buffer, like a `[u8; 128]`, as a message involves two expensive `memcpy`s. -Indirection can minimize message passing overhead: -instead of sending the buffer by value, one can send an owning pointer into the -buffer. +Indirection can minimize message passing overhead: instead of sending the buffer by value, one can send an owning pointer into the buffer. -One can use a global memory allocator to achieve indirection (`alloc::Box`, -`alloc::Rc`, etc.), which requires using the nightly channel as of Rust v1.37.0, -or one can use a statically allocated memory pool like [`heapless::Pool`]. +One can use a global memory allocator to achieve indirection (`alloc::Box`, `alloc::Rc`, etc.), which requires using the nightly channel as of Rust v1.37.0, or one can use a statically allocated memory pool like [`heapless::Pool`]. [`heapless::Pool`]: https://docs.rs/heapless/0.5.0/heapless/pool/index.html -As this example of approach goes completely outside of RTIC resource -model with shared and local the program would rely on the correctness -of the memory allocator, in this case `heapless::pool`. +As this example of approach goes completely outside of RTIC resource model with shared and local the program would rely on the correctness of the memory allocator, in this case `heapless::pool`. Here's an example where `heapless::Pool` is used to "box" buffers of 128 bytes. ``` rust -{{#include ../../../../examples/pool.rs}} +{{#include ../../../../rtic/examples/pool.rs}} ``` ``` console $ cargo run --target thumbv7m-none-eabi --example pool -{{#include ../../../../ci/expected/pool.run}} +``` + +``` console +{{#include ../../../../rtic/ci/expected/pool.run}} ``` -- cgit v1.2.3