Merge "simpleperf: check dump stack size and adjust its default value."
diff --git a/simpleperf/cmd_record.cpp b/simpleperf/cmd_record.cpp
index 9cec453..050ca85 100644
--- a/simpleperf/cmd_record.cpp
+++ b/simpleperf/cmd_record.cpp
@@ -61,6 +61,10 @@
constexpr uint64_t DEFAULT_SAMPLE_FREQ_FOR_NONTRACEPOINT_EVENT = 4000;
constexpr uint64_t DEFAULT_SAMPLE_PERIOD_FOR_TRACEPOINT_EVENT = 1;
+// The max size of records dumped by kernel is 65535, and dump stack size
+// should be a multiply of 8, so MAX_DUMP_STACK_SIZE is 65528.
+constexpr uint32_t MAX_DUMP_STACK_SIZE = 65528;
+
class RecordCommand : public Command {
public:
RecordCommand()
@@ -77,7 +81,7 @@
"--call-graph fp | dwarf[,<dump_stack_size>]\n"
" Enable call graph recording. Use frame pointer or dwarf debug\n"
" frame as the method to parse call graph in stack.\n"
-" Default is dwarf,8192.\n"
+" Default is dwarf,65528.\n"
"--cpu cpu_item1,cpu_item2,...\n"
" Collect samples only on the selected cpus. cpu_item can be cpu\n"
" number like 1, or cpu range like 0-3.\n"
@@ -143,7 +147,7 @@
branch_sampling_(0),
fp_callchain_sampling_(false),
dwarf_callchain_sampling_(false),
- dump_stack_size_in_dwarf_sampling_(8192),
+ dump_stack_size_in_dwarf_sampling_(MAX_DUMP_STACK_SIZE),
unwind_dwarf_callchain_(true),
post_unwind_(false),
child_inherit_(true),
@@ -373,6 +377,12 @@
<< " is not 8-byte aligned.";
return false;
}
+ if (size >= MAX_DUMP_STACK_SIZE) {
+ LOG(ERROR) << "dump stack size " << size
+ << " is bigger than max allowed size "
+ << MAX_DUMP_STACK_SIZE << ".";
+ return false;
+ }
dump_stack_size_in_dwarf_sampling_ = static_cast<uint32_t>(size);
}
} else {
diff --git a/simpleperf/cmd_record_test.cpp b/simpleperf/cmd_record_test.cpp
index 9313cbe..31ea173 100644
--- a/simpleperf/cmd_record_test.cpp
+++ b/simpleperf/cmd_record_test.cpp
@@ -141,6 +141,7 @@
if (IsDwarfCallChainSamplingSupported()) {
ASSERT_TRUE(RunRecordCmd({"--call-graph", "dwarf"}));
ASSERT_TRUE(RunRecordCmd({"--call-graph", "dwarf,16384"}));
+ ASSERT_FALSE(RunRecordCmd({"--call-graph", "dwarf,65536"}));
ASSERT_TRUE(RunRecordCmd({"-g"}));
} else {
GTEST_LOG_(INFO) << "This test does nothing as dwarf callchain sampling is "
