Merge "tp: fix tracking when process reuse happens before ftrace starts" into main
diff --git a/src/trace_processor/importers/common/process_tracker.cc b/src/trace_processor/importers/common/process_tracker.cc
index 3fc95fc..e292801 100644
--- a/src/trace_processor/importers/common/process_tracker.cc
+++ b/src/trace_processor/importers/common/process_tracker.cc
@@ -356,6 +356,17 @@
UniquePid upid = GetOrCreateProcess(pid);
auto* process_table = context_->storage->mutable_process_table();
+ // If we both know the previous and current parent pid and the two are not
+ // matching, we must have died and restarted: create a new process.
+ if (pupid) {
+ std::optional<UniquePid> prev_parent_upid =
+ process_table->parent_upid()[upid];
+ if (prev_parent_upid && prev_parent_upid != pupid) {
+ upid = StartNewProcess(std::nullopt, ppid, pid, kNullStringId,
+ ThreadNamePriority::kOther);
+ }
+ }
+
StringId proc_name_id = context_->storage->InternString(name);
process_table->mutable_name()->Set(upid, proc_name_id);
process_table->mutable_cmdline()->Set(
diff --git a/test/trace_processor/diff_tests/parser/process_tracking/process_tracking_exec.py b/test/trace_processor/diff_tests/parser/process_tracking/process_tracking_exec.py
index a706d7e..83e1034 100644
--- a/test/trace_processor/diff_tests/parser/process_tracking/process_tracking_exec.py
+++ b/test/trace_processor/diff_tests/parser/process_tracking/process_tracking_exec.py
@@ -22,24 +22,25 @@
trace = synth_common.create_trace()
-# Create a parent process which will be forked below.
+# Create a parent process which will be forked below.
trace.add_packet(ts=1)
trace.add_process(10, 0, "parent")
-# Fork off the new process and then kill it 5ns later.
+# Fork the process into a child.
trace.add_ftrace_packet(0)
trace.add_newtask(ts=15, tid=10, new_tid=11, new_comm='child', flags=0)
trace.add_sched(ts=16, prev_pid=10, next_pid=11, next_comm='child')
-# Create a parent process which will be forked below.
+# Scrape event for the forked process.
trace.add_packet(ts=20)
-trace.add_process(11, 0, "child_process")
+trace.add_process(11, 10, "child_process")
+# Rename of the main thread of forked process.
trace.add_ftrace_packet(0)
trace.add_rename(
ts=25, tid=11, old_comm='child', new_comm='true_name', oom_score_adj=1000)
-# Create a parent process which will be forked below.
+# Scrape of the forked process.
trace.add_packet(ts=30)
trace.add_process(11, 10, "true_process_name")
diff --git a/test/trace_processor/diff_tests/parser/process_tracking/synth_process_tracking.py b/test/trace_processor/diff_tests/parser/process_tracking/synth_process_tracking.py
index 68641ad..19bf834 100644
--- a/test/trace_processor/diff_tests/parser/process_tracking/synth_process_tracking.py
+++ b/test/trace_processor/diff_tests/parser/process_tracking/synth_process_tracking.py
@@ -90,7 +90,7 @@
ts=28, prev_pid=32, next_pid=40, prev_comm='p3-t2', next_comm='p4-t0')
trace.add_packet(ts=29)
-trace.add_process(40, 0, "process_4")
+trace.add_process(40, 30, "process_4")
# And now, this new process starts a new thread that recycles TID=31 (previously
# used as p3-t1, now becomes p4-t1).
