Add duration parameter and cleanup on panic

src/args.rs

@@ -62,7 +62,7 @@ pub struct Opt {
     #[structopt(short = "o", long)]
     pub allpids: bool,
 
-    /// Trace duration (iff run ftrace only)
+    /// Trace duration (necessary if running with ftrace only)
     #[structopt(short = "l", long)]
     pub ftrace_len: Option<Time>,
 } 

src/events_generation/ftrace.rs

@@ -48,7 +48,10 @@ impl EventsGenerator for FTraceEVG {
         loop {
             /* Continue to flush the remaining contents of the pipes.
                After this, read_stream_parse() returns Some until the pipes are empty */
-            if !self.recorders_stopped && (self.duration_reached() || self.targets_are_dead()) {
+            if !self.recorders_stopped && 
+                (self.targets_are_dead() || 
+                crate::params::ftrace_stop_on_timeout() && self.duration_reached()) {
+
                 self.disable_tracing_stop_recorders();
             }
 
@@ -145,7 +148,7 @@ impl FTraceEVG {
             processed_events: 0,
             processed_events_all: 0,
             start_time: std::time::Instant::now(), // Will be set when reading the first event
-            duration: 100000, // TODO use arg
+            duration: crate::params::ftrace_lifetime_sec(),
             recorders_stopped: false,
             extra_event: None,
 
@@ -271,7 +274,7 @@ fn is_deactivation(raw_event: &bindings::rbftrace_event_raw) -> bool {
     return !is_preemption(raw_event);
 }
 
-// It's important to do this to avoid errors in the invocation cycle in the next run
+/* Cleanup on ctrl+C */
 // TODO this is very ugly, but rust won't let the use the EVG instance because of the presence of raw pointers
 fn sigint_handle() {
     // Stop tracing
@@ -280,3 +283,10 @@ fn sigint_handle() {
     fs::write("/sys/kernel/debug/tracing/trace", " ").expect("Can't write to file 'trace'");
     std::process::exit(0);
 }
+
+/* Cleanup on panic */
+impl Drop for FTraceEVG {
+    fn drop(&mut self) {
+        self.shutdown();
+    }
+}

src/params.rs

@@ -29,6 +29,8 @@ pub static mut FTRACE_BUF_SIZE: u32 = 65536;
 // Use RBFtrace as a wrapper for ftrace, trace for FTRACE_LIFETIME_SEC seconds.
 pub static mut FTRACE_ONLY: bool = false;
 pub static mut FTRACE_LIFETIME_SEC: Time = 180;
+// Normally we stop when all target pids died. If this is true, we will stop after FTRACE_LIFETIME_SEC
+pub static mut FTRACE_STOP_ON_TIMEOUT: bool = false;
 // Trace every pid, not only rt pids
 pub static mut FTRACE_ALL_PIDS: bool = false;
 
@@ -158,6 +160,7 @@ pub fn set_from_args(args: Opt) {
         }
         if args.ftrace_len.is_some() {
             FTRACE_LIFETIME_SEC = args.ftrace_len.unwrap();
+            FTRACE_STOP_ON_TIMEOUT = true;
         }
     }
 }
@@ -208,6 +211,9 @@ pub fn ftrace_only() -> bool {
 pub fn ftrace_lifetime_sec() -> u64 {
     unsafe { return FTRACE_LIFETIME_SEC; }
 }
+pub fn ftrace_stop_on_timeout() -> bool {
+    unsafe { return FTRACE_STOP_ON_TIMEOUT; }
+}
 pub fn ftrace_all_pids() -> bool {
     unsafe { return FTRACE_ALL_PIDS; }
 }