elf_runner/
crash_info.rs

1// Copyright 2023 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use futures::lock::Mutex;
6use log::*;
7use moniker::Moniker;
8use std::sync::Arc;
9use {fidl_fuchsia_sys2 as fsys, fuchsia_async as fasync};
10
11/// Any stored data is removed after this amount of time
12const CLEANUP_DEADLINE_SECONDS: i64 = 600;
13
14#[derive(Debug, Clone, PartialEq)]
15pub struct ComponentCrashInfo {
16    pub url: String,
17    pub moniker: Moniker,
18}
19
20impl Into<fsys::ComponentCrashInfo> for ComponentCrashInfo {
21    fn into(self) -> fsys::ComponentCrashInfo {
22        fsys::ComponentCrashInfo {
23            url: Some(self.url),
24            moniker: Some(self.moniker.to_string()),
25            ..Default::default()
26        }
27    }
28}
29
30#[derive(Debug, Clone, PartialEq)]
31pub(crate) struct Record {
32    // The point at which this record should be deleted
33    deadline: zx::MonotonicInstant,
34    // The koid of the thread a crash was observed on
35    koid: zx::Koid,
36    // The crash information
37    crash_info: ComponentCrashInfo,
38}
39
40#[derive(Clone)]
41pub struct CrashRecords {
42    records: Arc<Mutex<Vec<Record>>>,
43    _cleanup_task: Arc<fasync::Task<()>>,
44}
45
46/// This task will inspect `records`, and sleep until either `records[0].deadline` or for
47/// `CLEANUP_DEADLINE_SECONDS` seconds. Upon waking, it removes anything from `records` whose
48/// deadline has passed, and then repeats.
49///
50/// If `records` is not sorted by `Record::deadline` in ascending order then this task will not
51/// behave correctly.
52async fn record_cleanup_task(records: Arc<Mutex<Vec<Record>>>) {
53    loop {
54        let sleep_until = {
55            let records_guard = records.lock().await;
56            if records_guard.is_empty() {
57                // If we have no records, then we can sleep for as long as the timeout and check
58                // again
59                zx::MonotonicInstant::after(zx::MonotonicDuration::from_seconds(
60                    CLEANUP_DEADLINE_SECONDS,
61                ))
62            } else {
63                // If there's an upcoming record to delete, sleep until then
64                records_guard[0].deadline.clone()
65            }
66        };
67        let timer = fasync::Timer::new(sleep_until);
68        timer.await;
69        let mut records_guard = records.lock().await;
70        while !records_guard.is_empty() && zx::MonotonicInstant::get() > records_guard[0].deadline {
71            records_guard.remove(0);
72        }
73    }
74}
75
76impl CrashRecords {
77    pub fn new() -> Self {
78        let records = Arc::new(Mutex::new(vec![]));
79        CrashRecords {
80            records: records.clone(),
81            _cleanup_task: Arc::new(fasync::Task::spawn(record_cleanup_task(records))),
82        }
83    }
84
85    /// Adds a new report to CrashRecords, and schedules the new reports deletion in
86    /// `CLEANUP_DEADLINE_SECONDS`.
87    pub async fn add_report(&self, thread_koid: zx::Koid, report: ComponentCrashInfo) {
88        self.records.lock().await.push(Record {
89            deadline: zx::MonotonicInstant::after(zx::MonotonicDuration::from_seconds(
90                CLEANUP_DEADLINE_SECONDS,
91            )),
92            koid: thread_koid.clone(),
93            crash_info: report,
94        });
95    }
96
97    /// Removes the report (if any), and deletes it.
98    pub async fn take_report(&self, thread_koid: &zx::Koid) -> Option<ComponentCrashInfo> {
99        let mut records_guard = self.records.lock().await;
100        let index_to_remove = records_guard
101            .iter()
102            .enumerate()
103            .find(|(_, record)| &record.koid == thread_koid)
104            .map(|(i, _)| i);
105        if index_to_remove.is_none() {
106            warn!("crash introspection failed to provide attribution for the crashed thread with koid {:?}", thread_koid);
107        }
108        index_to_remove.map(|i| records_guard.remove(i).crash_info)
109    }
110}
elf_runner/crash_info.rs

elf_runner/
crash_info.rs
