crash_dump: add tracing.
Add some tracing to figure out where time is going during a dump.
Bug: http://b/62112103
Test: systrace.py sched freq idle bionic
Change-Id: Ic2a212beeb0bb0350b4d9c2cd7a4e70adc97752d
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 558bc72..df7201d 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -44,6 +44,9 @@
#include <private/android_filesystem_config.h>
#include <procinfo/process.h>
+#define ATRACE_TAG ATRACE_TAG_BIONIC
+#include <utils/Trace.h>
+
#include "backtrace.h"
#include "tombstone.h"
#include "utility.h"
@@ -101,6 +104,7 @@
}
static bool activity_manager_notify(pid_t pid, int signal, const std::string& amfd_data) {
+ ATRACE_CALL();
android::base::unique_fd amfd(socket_local_client(
"/data/system/ndebugsocket", ANDROID_SOCKET_NAMESPACE_FILESYSTEM, SOCK_STREAM));
if (amfd.get() == -1) {
@@ -176,6 +180,7 @@
}
static void drop_capabilities() {
+ ATRACE_CALL();
__user_cap_header_struct capheader;
memset(&capheader, 0, sizeof(capheader));
capheader.version = _LINUX_CAPABILITY_VERSION_3;
@@ -194,6 +199,8 @@
}
int main(int argc, char** argv) {
+ atrace_begin(ATRACE_TAG, "before reparent");
+
pid_t target = getppid();
bool tombstoned_connected = false;
unique_fd tombstoned_socket;
@@ -261,6 +268,8 @@
PLOG(FATAL) << "parent died";
}
+ atrace_end(ATRACE_TAG);
+
// Reparent ourselves to init, so that the signal handler can waitpid on the
// original process to avoid leaving a zombie for non-fatal dumps.
pid_t forkpid = fork();
@@ -270,47 +279,60 @@
exit(0);
}
+ ATRACE_NAME("after reparent");
+
// Die if we take too long.
alarm(2);
std::string attach_error;
- // Seize the main thread.
- if (!ptrace_seize_thread(target_proc_fd, main_tid, &attach_error)) {
- LOG(FATAL) << attach_error;
- }
-
- // Seize the siblings.
std::map<pid_t, std::string> threads;
+
{
- std::set<pid_t> siblings;
- if (!android::procinfo::GetProcessTids(target, &siblings)) {
- PLOG(FATAL) << "failed to get process siblings";
+ ATRACE_NAME("ptrace");
+ // Seize the main thread.
+ if (!ptrace_seize_thread(target_proc_fd, main_tid, &attach_error)) {
+ LOG(FATAL) << attach_error;
}
- // but not the already attached main thread.
- siblings.erase(main_tid);
- // or the handler pseudothread.
- siblings.erase(pseudothread_tid);
+ // Seize the siblings.
+ {
+ std::set<pid_t> siblings;
+ if (!android::procinfo::GetProcessTids(target, &siblings)) {
+ PLOG(FATAL) << "failed to get process siblings";
+ }
- for (pid_t sibling_tid : siblings) {
- if (!ptrace_seize_thread(target_proc_fd, sibling_tid, &attach_error)) {
- LOG(WARNING) << attach_error;
- } else {
- threads.emplace(sibling_tid, get_thread_name(sibling_tid));
+ // but not the already attached main thread.
+ siblings.erase(main_tid);
+ // or the handler pseudothread.
+ siblings.erase(pseudothread_tid);
+
+ for (pid_t sibling_tid : siblings) {
+ if (!ptrace_seize_thread(target_proc_fd, sibling_tid, &attach_error)) {
+ LOG(WARNING) << attach_error;
+ } else {
+ threads.emplace(sibling_tid, get_thread_name(sibling_tid));
+ }
}
}
}
// Collect the backtrace map, open files, and process/thread names, while we still have caps.
- std::unique_ptr<BacktraceMap> backtrace_map(BacktraceMap::Create(main_tid));
- if (!backtrace_map) {
- LOG(FATAL) << "failed to create backtrace map";
+ std::unique_ptr<BacktraceMap> backtrace_map;
+ {
+ ATRACE_NAME("backtrace map");
+ backtrace_map.reset(BacktraceMap::Create(main_tid));
+ if (!backtrace_map) {
+ LOG(FATAL) << "failed to create backtrace map";
+ }
}
// Collect the list of open files.
OpenFilesList open_files;
- populate_open_files_list(target, &open_files);
+ {
+ ATRACE_NAME("open files");
+ populate_open_files_list(target, &open_files);
+ }
std::string process_name = get_process_name(main_tid);
threads.emplace(main_tid, get_thread_name(main_tid));
@@ -318,9 +340,12 @@
// Drop our capabilities now that we've attached to the threads we care about.
drop_capabilities();
- const DebuggerdDumpType dump_type_enum = static_cast<DebuggerdDumpType>(dump_type);
- LOG(INFO) << "obtaining output fd from tombstoned, type: " << dump_type_enum;
- tombstoned_connected = tombstoned_connect(target, &tombstoned_socket, &output_fd, dump_type_enum);
+ {
+ ATRACE_NAME("tombstoned_connect");
+ const DebuggerdDumpType dump_type_enum = static_cast<DebuggerdDumpType>(dump_type);
+ LOG(INFO) << "obtaining output fd from tombstoned, type: " << dump_type_enum;
+ tombstoned_connected = tombstoned_connect(target, &tombstoned_socket, &output_fd, dump_type_enum);
+ }
// Write a '\1' to stdout to tell the crashing process to resume.
// It also restores the value of PR_SET_DUMPABLE at this point.
@@ -349,9 +374,12 @@
}
siginfo_t siginfo = {};
- if (!wait_for_signal(main_tid, &siginfo)) {
- printf("failed to wait for signal in tid %d: %s\n", main_tid, strerror(errno));
- exit(1);
+ {
+ ATRACE_NAME("wait_for_signal");
+ if (!wait_for_signal(main_tid, &siginfo)) {
+ printf("failed to wait for signal in tid %d: %s\n", main_tid, strerror(errno));
+ exit(1);
+ }
}
int signo = siginfo.si_signo;
@@ -373,8 +401,10 @@
std::string amfd_data;
if (backtrace) {
+ ATRACE_NAME("dump_backtrace");
dump_backtrace(output_fd.get(), backtrace_map.get(), target, main_tid, process_name, threads, 0);
} else {
+ ATRACE_NAME("engrave_tombstone");
engrave_tombstone(output_fd.get(), backtrace_map.get(), &open_files, target, main_tid,
process_name, threads, abort_address, fatal_signal ? &amfd_data : nullptr);
}