Small example for benchmarking some cpu ops (#394)

* Refactor the benchmark example.

* Rename the example.

* Add some comments.

candle-core/examples/conv1d_benchmark.rs

@@ -1,24 +0,0 @@
-#[cfg(feature = "mkl")]
-extern crate intel_mkl_src;
-
-#[cfg(feature = "accelerate")]
-extern crate accelerate_src;
-
-use anyhow::Result;
-use candle_core::{Device, Tensor};
-
-pub const N_ITERS: usize = 5;
-
-fn main() -> Result<()> {
-    let inp = Tensor::randn(0f32, 1., (1, 384, 3000), &Device::Cpu)?;
-    let w = Tensor::randn(0f32, 1., (384, 384, 3), &Device::Cpu)?;
-    let res = inp.conv1d(&w, 0, 1);
-    println!("{res:?}");
-    let start = std::time::Instant::now();
-    for i in 0..N_ITERS {
-        let res = inp.conv1d(&w, 0, 1);
-        println!("{i} {res:?}");
-    }
-    println!("{:?}", start.elapsed() / N_ITERS as u32);
-    Ok(())
-}

candle-core/examples/cpu_benchmarks.rs

@@ -0,0 +1,95 @@
+/// This example contains some simple benchmarks so that it's easy to run them in perf etc.
+#[cfg(feature = "mkl")]
+extern crate intel_mkl_src;
+
+#[cfg(feature = "accelerate")]
+extern crate accelerate_src;
+
+use candle_core::{Device, Result, Tensor};
+use clap::{Parser, Subcommand};
+
+trait Benchmark {
+    type PreProcessData;
+    type RunResult;
+
+    fn preprocess() -> Result<Self::PreProcessData>;
+    fn run_one(_: &Self::PreProcessData) -> Result<Self::RunResult>;
+
+    const ITERS: usize;
+}
+
+// Conv1d example as used in whisper.
+struct Conv1d;
+impl Benchmark for Conv1d {
+    type PreProcessData = (Tensor, Tensor);
+    type RunResult = Tensor;
+    fn preprocess() -> Result<Self::PreProcessData> {
+        let inp = Tensor::randn(0f32, 1., (1, 384, 3000), &Device::Cpu)?;
+        let w = Tensor::randn(0f32, 1., (384, 384, 3), &Device::Cpu)?;
+        Ok((inp, w))
+    }
+
+    fn run_one(d: &Self::PreProcessData) -> Result<Self::RunResult> {
+        d.0.conv1d(&d.1, 0, 1)
+    }
+
+    const ITERS: usize = 5;
+}
+
+// Conv2d example as used in stable-diffusion.
+struct Conv2d;
+impl Benchmark for Conv2d {
+    type PreProcessData = (Tensor, Tensor);
+    type RunResult = Tensor;
+
+    fn preprocess() -> Result<Self::PreProcessData> {
+        let inp = Tensor::randn(0f32, 1., (2, 320, 96, 96), &Device::Cpu)?;
+        let w = Tensor::randn(0f32, 1., (320, 320, 3, 3), &Device::Cpu)?;
+        Ok((inp, w))
+    }
+
+    fn run_one(d: &Self::PreProcessData) -> Result<Self::RunResult> {
+        d.0.conv2d(&d.1, 0, 1)
+    }
+
+    const ITERS: usize = 1;
+}
+
+fn run<B: Benchmark>(iters: Option<usize>) -> Result<()> {
+    use std::hint::black_box;
+
+    let iters = iters.unwrap_or(B::ITERS);
+    let d = B::preprocess()?;
+    let start = std::time::Instant::now();
+    for _iter in 0..iters {
+        let _res = black_box(B::run_one(black_box(&d))?);
+    }
+    println!("{:?}", start.elapsed() / iters as u32);
+    Ok(())
+}
+
+#[derive(Subcommand, Debug, Clone)]
+enum Task {
+    Conv1d,
+    Conv2d,
+}
+
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+pub struct Args {
+    /// The benchmark to be run.
+    #[command(subcommand)]
+    task: Task,
+
+    #[arg(long)]
+    iters: Option<usize>,
+}
+
+fn main() -> Result<()> {
+    let args = Args::parse();
+    match args.task {
+        Task::Conv1d => run::<Conv1d>(args.iters)?,
+        Task::Conv2d => run::<Conv2d>(args.iters)?,
+    }
+    Ok(())
+}