4148: Simplify profiler impl (bubble up Option) r=matklad a=Veetaha



Co-authored-by: veetaha <veetaha2@gmail.com>
This commit is contained in:
bors[bot] 2020-04-28 18:44:34 +00:00 committed by GitHub
commit 9230ae5492
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@ -30,8 +30,9 @@ pub fn init_from(spec: &str) {
pub type Label = &'static str;
/// This function starts a profiling scope in the current execution stack with a given description.
/// It returns a Profile structure and measure elapsed time between this method invocation and Profile structure drop.
/// It supports nested profiling scopes in case when this function invoked multiple times at the execution stack. In this case the profiling information will be nested at the output.
/// It returns a `Profile` struct that measures elapsed time between this method invocation and `Profile` struct drop.
/// It supports nested profiling scopes in case when this function is invoked multiple times at the execution stack.
/// In this case the profiling information will be nested at the output.
/// Profiling information is being printed in the stderr.
///
/// # Example
@ -58,36 +59,35 @@ pub type Label = &'static str;
/// ```
pub fn profile(label: Label) -> Profiler {
assert!(!label.is_empty());
let enabled = PROFILING_ENABLED.load(Ordering::Relaxed)
&& PROFILE_STACK.with(|stack| stack.borrow_mut().push(label));
let label = if enabled { Some(label) } else { None };
Profiler { label, detail: None }
if PROFILING_ENABLED.load(Ordering::Relaxed)
&& PROFILE_STACK.with(|stack| stack.borrow_mut().push(label))
{
Profiler(Some(ProfilerImpl { label, detail: None }))
} else {
Profiler(None)
}
}
pub struct Profiler {
label: Option<Label>,
pub struct Profiler(Option<ProfilerImpl>);
struct ProfilerImpl {
label: Label,
detail: Option<String>,
}
impl Profiler {
pub fn detail(mut self, detail: impl FnOnce() -> String) -> Profiler {
if self.label.is_some() {
self.detail = Some(detail())
if let Some(profiler) = &mut self.0 {
profiler.detail = Some(detail())
}
self
}
}
impl Drop for Profiler {
impl Drop for ProfilerImpl {
fn drop(&mut self) {
match self {
Profiler { label: Some(label), detail } => {
PROFILE_STACK.with(|stack| {
stack.borrow_mut().pop(label, detail.take());
});
}
Profiler { label: None, .. } => (),
}
PROFILE_STACK.with(|it| it.borrow_mut().pop(self.label, self.detail.take()));
}
}
@ -179,21 +179,18 @@ impl ProfileStack {
pub fn pop(&mut self, label: Label, detail: Option<String>) {
let start = self.starts.pop().unwrap();
let duration = start.elapsed();
let level = self.starts.len();
self.messages.finish(Message { duration, label, detail });
if level == 0 {
if self.starts.is_empty() {
let longer_than = self.filter.longer_than;
// Convert to millis for comparison to avoid problems with rounding
// (otherwise we could print `0ms` despite user's `>0` filter when
// `duration` is just a few nanos).
if duration.as_millis() > longer_than.as_millis() {
let stderr = stderr();
if let Some(root) = self.messages.root() {
print(&self.messages, root, 0, longer_than, &mut stderr.lock());
print(&self.messages, root, 0, longer_than, &mut stderr().lock());
}
}
self.messages.clear();
assert!(self.starts.is_empty())
}
}
}