examples: add glcontext

Author: gdesmott

examples/glcontext.rs

@@ -0,0 +1,93 @@
+// Copyright (C) 2025 Guillaume Desmottes <[email protected]>
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::{collections::HashMap, fs::File};
+
+use gst_log_parser::parse;
+use gstreamer as gst;
+use structopt::StructOpt;
+
+#[derive(StructOpt)]
+#[structopt(
+    name = "glcontext",
+    about = "Check for how long it takes for functions to be scheduled in the GL thread"
+)]
+struct Opt {
+    #[structopt(help = "Input file")]
+    input: String,
+}
+
+fn print_stats(times: Vec<gst::ClockTime>) {
+    let n = times.len();
+    println!("{n} function calls. Schedule times:");
+    if n == 0 {
+        return;
+    }
+    let (min_idx, min) = times
+        .iter()
+        .enumerate()
+        .min_by(|(_a_idx, a), (_b_idx, b)| a.cmp(b))
+        .unwrap();
+    let (max_idx, max) = times
+        .iter()
+        .enumerate()
+        .max_by(|(_a_idx, a), (_b_idx, b)| a.cmp(b))
+        .unwrap();
+    println!("  min: {min} (call {min_idx})");
+    println!("  max: {max} (call {max_idx})");
+    let sum: gst::ClockTime = times.into_iter().sum();
+    let avg = sum.nseconds() / n as u64;
+    let avg = gst::ClockTime::from_nseconds(avg);
+    println!("  avg: {avg}");
+}
+
+fn main() -> anyhow::Result<()> {
+    let opt = Opt::from_args();
+    let f = File::open(opt.input)?;
+
+    let add_re = regex::Regex::new(r"schedule function:(?<function>.*) data:(?<data>.*)")?;
+    let run_re = regex::Regex::new(r"running function:(?<function>.*) data:(?<data>.*)")?;
+    let mut pendings = HashMap::new();
+    let mut times = vec![];
+
+    let parsed = parse(f);
+    for entry in parsed
+        .filter(|entry| entry.category == "glcontext" && entry.level == gst::DebugLevel::Trace)
+    {
+        match entry.function.as_str() {
+            "gst_gl_context_thread_add" => {
+                let Some(capture) = add_re.captures(&entry.message) else {
+                    continue;
+                };
+                pendings.insert(
+                    (
+                        (capture["function"]).to_string(),
+                        (capture["data"]).to_string(),
+                    ),
+                    entry.ts,
+                );
+            }
+            "_gst_gl_context_thread_run_generic" => {
+                let Some(capture) = run_re.captures(&entry.message) else {
+                    continue;
+                };
+                if let Some(pending) = pendings.remove(&(
+                    (capture["function"]).to_string(),
+                    (capture["data"]).to_string(),
+                )) {
+                    times.push(entry.ts - pending);
+                }
+            }
+            _ => {}
+        }
+    }
+
+    print_stats(times);
+
+    Ok(())
+}