Speed up map creation.
- Rewrite the Maps::Parse to use open, and a buffer on the stack.
- Rewrite the line parser away from sscanf. The current way sscanf
is used does not catch many malformed lines. In addition, this
new version improves performance by 50% over sscanf on sailfish.
- Add a lot of unit tests for the parser to make sure there are
no problems. In addition, add a special line that was not rejected
with the previous version of the code.
- Add new accessor to get the map at a particular index.
- Add a backtrace benchmark for map creation for both new and old.
This cl results in ~5% speedup and makes the new unwinder map creation
about the same for 64 bit. It's still a bit slower, but not by much.
On 32 bit, we are still about 5% slower than the old creation method,
though.
Bug: 23762183
Test: libunwindstack unit tests pass. Ran the new benchmarks.
Change-Id: Id4431e539f400984e6fad62153fdf4152d518322
diff --git a/libunwindstack/tests/MapsTest.cpp b/libunwindstack/tests/MapsTest.cpp
index 9430cf3..2d15a4e 100644
--- a/libunwindstack/tests/MapsTest.cpp
+++ b/libunwindstack/tests/MapsTest.cpp
@@ -14,9 +14,11 @@
* limitations under the License.
*/
+#include <inttypes.h>
#include <sys/mman.h>
#include <android-base/file.h>
+#include <android-base/stringprintf.h>
#include <android-base/test_utils.h>
#include <gtest/gtest.h>
@@ -24,13 +26,116 @@
namespace unwindstack {
+static void VerifyLine(std::string line, MapInfo* info) {
+ BufferMaps maps(line.c_str());
+
+ if (info == nullptr) {
+ ASSERT_FALSE(maps.Parse()) << "Failed on: " + line;
+ } else {
+ ASSERT_TRUE(maps.Parse()) << "Failed on: " + line;
+ MapInfo* element = maps.Get(0);
+ ASSERT_TRUE(element != nullptr) << "Failed on: " + line;
+ *info = *element;
+ }
+}
+
+TEST(MapsTest, verify_parse_line) {
+ MapInfo info;
+
+ VerifyLine("01-02 rwxp 03 04:05 06\n", &info);
+ EXPECT_EQ(1U, info.start);
+ EXPECT_EQ(2U, info.end);
+ EXPECT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, info.flags);
+ EXPECT_EQ(3U, info.offset);
+ EXPECT_EQ("", info.name);
+
+ VerifyLine("0a-0b ---s 0c 0d:0e 06 /fake/name\n", &info);
+ EXPECT_EQ(0xaU, info.start);
+ EXPECT_EQ(0xbU, info.end);
+ EXPECT_EQ(0U, info.flags);
+ EXPECT_EQ(0xcU, info.offset);
+ EXPECT_EQ("/fake/name", info.name);
+
+ VerifyLine("01-02 rwxp 03 04:05 06 /fake/name/again\n", &info);
+ EXPECT_EQ(1U, info.start);
+ EXPECT_EQ(2U, info.end);
+ EXPECT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, info.flags);
+ EXPECT_EQ(3U, info.offset);
+ EXPECT_EQ("/fake/name/again", info.name);
+
+ VerifyLine("-00 rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00- rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 00 :00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 00 00:00 \n", nullptr);
+ VerifyLine("x-00 rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00 -00 rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00-x rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00-x rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00-00x rwxp 00 00:00 0\n", nullptr);
+ VerifyLine("00-00 rwxp0 00 00:00 0\n", nullptr);
+ VerifyLine("00-00 rwxp0 00 00:00 0\n", nullptr);
+ VerifyLine("00-00 rwp 00 00:00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 0000:00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 00 00 :00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 00 00: 00 0\n", nullptr);
+ VerifyLine("00-00 rwxp 00 00:000\n", nullptr);
+ VerifyLine("00-00 rwxp 00 00:00 0/fake\n", nullptr);
+ VerifyLine("00-00 xxxx 00 00:00 0 /fake\n", nullptr);
+ VerifyLine("00-00 ywxp 00 00:00 0 /fake\n", nullptr);
+ VerifyLine("00-00 ryxp 00 00:00 0 /fake\n", nullptr);
+ VerifyLine("00-00 rwyp 00 00:00 0 /fake\n", nullptr);
+ VerifyLine("00-00 rwx- 00 00:00 0 /fake\n", nullptr);
+ VerifyLine("0\n", nullptr);
+ VerifyLine("00\n", nullptr);
+ VerifyLine("00-\n", nullptr);
+ VerifyLine("00-0\n", nullptr);
+ VerifyLine("00-00\n", nullptr);
+ VerifyLine("00-00 \n", nullptr);
+ VerifyLine("00-00 -\n", nullptr);
+ VerifyLine("00-00 r\n", nullptr);
+ VerifyLine("00-00 --\n", nullptr);
+ VerifyLine("00-00 rw\n", nullptr);
+ VerifyLine("00-00 ---\n", nullptr);
+ VerifyLine("00-00 rwx\n", nullptr);
+ VerifyLine("00-00 ---s\n", nullptr);
+ VerifyLine("00-00 ---p\n", nullptr);
+ VerifyLine("00-00 ---s 0\n", nullptr);
+ VerifyLine("00-00 ---p 0 \n", nullptr);
+ VerifyLine("00-00 ---p 0 0\n", nullptr);
+ VerifyLine("00-00 ---p 0 0:\n", nullptr);
+ VerifyLine("00-00 ---p 0 0:0\n", nullptr);
+ VerifyLine("00-00 ---p 0 0:0 \n", nullptr);
+
+ // Line to verify that the parser will detect a completely malformed line
+ // properly.
+ VerifyLine("7ffff7dda000-7ffff7dfd7ffff7ff3000-7ffff7ff4000 ---p 0000f000 fc:02 44171565\n",
+ nullptr);
+}
+
+TEST(MapsTest, verify_large_values) {
+ MapInfo info;
+#if defined(__LP64__)
+ VerifyLine("fabcdef012345678-f12345678abcdef8 rwxp f0b0d0f010305070 00:00 0\n", &info);
+ EXPECT_EQ(0xfabcdef012345678UL, info.start);
+ EXPECT_EQ(0xf12345678abcdef8UL, info.end);
+ EXPECT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, info.flags);
+ EXPECT_EQ(0xf0b0d0f010305070UL, info.offset);
+#else
+ VerifyLine("f2345678-fabcdef8 rwxp f0305070 00:00 0\n", &info);
+ EXPECT_EQ(0xf2345678UL, info.start);
+ EXPECT_EQ(0xfabcdef8UL, info.end);
+ EXPECT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, info.flags);
+ EXPECT_EQ(0xf0305070UL, info.offset);
+#endif
+}
+
TEST(MapsTest, parse_permissions) {
BufferMaps maps(
- "1000-2000 ---- 00000000 00:00 0\n"
- "2000-3000 r--- 00000000 00:00 0\n"
- "3000-4000 -w-- 00000000 00:00 0\n"
- "4000-5000 --x- 00000000 00:00 0\n"
- "5000-6000 rwx- 00000000 00:00 0\n");
+ "1000-2000 ---s 00000000 00:00 0\n"
+ "2000-3000 r--s 00000000 00:00 0\n"
+ "3000-4000 -w-s 00000000 00:00 0\n"
+ "4000-5000 --xp 00000000 00:00 0\n"
+ "5000-6000 rwxp 00000000 00:00 0\n");
ASSERT_TRUE(maps.Parse());
ASSERT_EQ(5U, maps.Total());
@@ -70,28 +175,28 @@
TEST(MapsTest, parse_name) {
BufferMaps maps(
- "720b29b000-720b29e000 rw-p 00000000 00:00 0\n"
- "720b29e000-720b29f000 rw-p 00000000 00:00 0 /system/lib/fake.so\n"
- "720b29f000-720b2a0000 rw-p 00000000 00:00 0");
+ "7b29b000-7b29e000 rw-p 00000000 00:00 0\n"
+ "7b29e000-7b29f000 rw-p 00000000 00:00 0 /system/lib/fake.so\n"
+ "7b29f000-7b2a0000 rw-p 00000000 00:00 0");
ASSERT_TRUE(maps.Parse());
ASSERT_EQ(3U, maps.Total());
auto it = maps.begin();
ASSERT_EQ("", it->name);
- ASSERT_EQ(0x720b29b000U, it->start);
- ASSERT_EQ(0x720b29e000U, it->end);
+ ASSERT_EQ(0x7b29b000U, it->start);
+ ASSERT_EQ(0x7b29e000U, it->end);
ASSERT_EQ(0U, it->offset);
ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
++it;
ASSERT_EQ("/system/lib/fake.so", it->name);
- ASSERT_EQ(0x720b29e000U, it->start);
- ASSERT_EQ(0x720b29f000U, it->end);
+ ASSERT_EQ(0x7b29e000U, it->start);
+ ASSERT_EQ(0x7b29f000U, it->end);
ASSERT_EQ(0U, it->offset);
ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
++it;
ASSERT_EQ("", it->name);
- ASSERT_EQ(0x720b29f000U, it->start);
- ASSERT_EQ(0x720b2a0000U, it->end);
+ ASSERT_EQ(0x7b29f000U, it->start);
+ ASSERT_EQ(0x7b2a0000U, it->end);
ASSERT_EQ(0U, it->offset);
ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
++it;
@@ -149,9 +254,9 @@
ASSERT_TRUE(tf.fd != -1);
ASSERT_TRUE(
- android::base::WriteStringToFile("720b29b000-720b29e000 r-xp a0000000 00:00 0 /fake.so\n"
- "720b2b0000-720b2e0000 r-xp b0000000 00:00 0 /fake2.so\n"
- "720b2e0000-720b2f0000 r-xp c0000000 00:00 0 /fake3.so\n",
+ android::base::WriteStringToFile("7b29b000-7b29e000 r-xp a0000000 00:00 0 /fake.so\n"
+ "7b2b0000-7b2e0000 r-xp b0000000 00:00 0 /fake2.so\n"
+ "7b2e0000-7b2f0000 r-xp c0000000 00:00 0 /fake3.so\n",
tf.path, 0660, getuid(), getgid()));
FileMaps maps(tf.path);
@@ -159,20 +264,20 @@
ASSERT_TRUE(maps.Parse());
ASSERT_EQ(3U, maps.Total());
auto it = maps.begin();
- ASSERT_EQ(0x720b29b000U, it->start);
- ASSERT_EQ(0x720b29e000U, it->end);
+ ASSERT_EQ(0x7b29b000U, it->start);
+ ASSERT_EQ(0x7b29e000U, it->end);
ASSERT_EQ(0xa0000000U, it->offset);
ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
ASSERT_EQ("/fake.so", it->name);
++it;
- ASSERT_EQ(0x720b2b0000U, it->start);
- ASSERT_EQ(0x720b2e0000U, it->end);
+ ASSERT_EQ(0x7b2b0000U, it->start);
+ ASSERT_EQ(0x7b2e0000U, it->end);
ASSERT_EQ(0xb0000000U, it->offset);
ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
ASSERT_EQ("/fake2.so", it->name);
++it;
- ASSERT_EQ(0x720b2e0000U, it->start);
- ASSERT_EQ(0x720b2f0000U, it->end);
+ ASSERT_EQ(0x7b2e0000U, it->start);
+ ASSERT_EQ(0x7b2f0000U, it->end);
ASSERT_EQ(0xc0000000U, it->offset);
ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
ASSERT_EQ("/fake3.so", it->name);
@@ -180,6 +285,163 @@
ASSERT_EQ(it, maps.end());
}
+TEST(MapsTest, file_no_map_name) {
+ TemporaryFile tf;
+ ASSERT_TRUE(tf.fd != -1);
+
+ ASSERT_TRUE(
+ android::base::WriteStringToFile("7b29b000-7b29e000 r-xp a0000000 00:00 0\n"
+ "7b2b0000-7b2e0000 r-xp b0000000 00:00 0 /fake2.so\n"
+ "7b2e0000-7b2f0000 r-xp c0000000 00:00 0 \n",
+ tf.path, 0660, getuid(), getgid()));
+
+ FileMaps maps(tf.path);
+
+ ASSERT_TRUE(maps.Parse());
+ ASSERT_EQ(3U, maps.Total());
+ auto it = maps.begin();
+ ASSERT_EQ(0x7b29b000U, it->start);
+ ASSERT_EQ(0x7b29e000U, it->end);
+ ASSERT_EQ(0xa0000000U, it->offset);
+ ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
+ ASSERT_EQ("", it->name);
+ ++it;
+ ASSERT_EQ(0x7b2b0000U, it->start);
+ ASSERT_EQ(0x7b2e0000U, it->end);
+ ASSERT_EQ(0xb0000000U, it->offset);
+ ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
+ ASSERT_EQ("/fake2.so", it->name);
+ ++it;
+ ASSERT_EQ(0x7b2e0000U, it->start);
+ ASSERT_EQ(0x7b2f0000U, it->end);
+ ASSERT_EQ(0xc0000000U, it->offset);
+ ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
+ ASSERT_EQ("", it->name);
+ ++it;
+ ASSERT_EQ(it, maps.end());
+}
+
+// Verify that a file that crosses a buffer is parsed correctly.
+static std::string CreateEntry(size_t index) {
+ return android::base::StringPrintf("%08zx-%08zx rwxp 0000 00:00 0\n", index * 4096,
+ (index + 1) * 4096);
+}
+
+TEST(MapsTest, file_buffer_cross) {
+ constexpr size_t kBufferSize = 2048;
+ TemporaryFile tf;
+ ASSERT_TRUE(tf.fd != -1);
+
+ // Compute how many to add in the first buffer.
+ size_t entry_len = CreateEntry(0).size();
+ size_t index;
+ std::string file_data;
+ for (index = 0; index < kBufferSize / entry_len; index++) {
+ file_data += CreateEntry(index);
+ }
+ // Add a long name to make sure that the first buffer does not contain a
+ // complete line.
+ // Remove the last newline.
+ size_t extra = 0;
+ size_t leftover = kBufferSize % entry_len;
+ size_t overlap1_index = 0;
+ std::string overlap1_name;
+ if (leftover == 0) {
+ // Exact match, add a long name to cross over the value.
+ overlap1_name = "/fake/name/is/long/on/purpose";
+ file_data.erase(file_data.size() - 1);
+ file_data += ' ' + overlap1_name + '\n';
+ extra = entry_len + overlap1_name.size() + 1;
+ overlap1_index = index;
+ }
+
+ // Compute how many need to go in to hit the buffer boundary exactly.
+ size_t bytes_left_in_buffer = kBufferSize - extra;
+ size_t entries_to_add = bytes_left_in_buffer / entry_len + index;
+ for (; index < entries_to_add; index++) {
+ file_data += CreateEntry(index);
+ }
+
+ // Now figure out how many bytes to add to get exactly to the buffer boundary.
+ leftover = bytes_left_in_buffer % entry_len;
+ std::string overlap2_name;
+ size_t overlap2_index = 0;
+ if (leftover != 0) {
+ file_data.erase(file_data.size() - 1);
+ file_data += ' ';
+ overlap2_name = std::string(leftover - 1, 'x');
+ file_data += overlap2_name + '\n';
+ overlap2_index = index - 1;
+ }
+
+ // Now add a few entries on the next page.
+ for (size_t start = index; index < start + 10; index++) {
+ file_data += CreateEntry(index);
+ }
+
+ ASSERT_TRUE(android::base::WriteStringToFile(file_data, tf.path, 0660, getuid(), getgid()));
+
+ FileMaps maps(tf.path);
+ ASSERT_TRUE(maps.Parse());
+ EXPECT_EQ(index, maps.Total());
+ // Verify all of the maps.
+ for (size_t i = 0; i < index; i++) {
+ MapInfo* info = maps.Get(i);
+ ASSERT_TRUE(info != nullptr) << "Failed verifying index " + std::to_string(i);
+ EXPECT_EQ(i * 4096, info->start) << "Failed verifying index " + std::to_string(i);
+ EXPECT_EQ((i + 1) * 4096, info->end) << "Failed verifying index " + std::to_string(i);
+ EXPECT_EQ(0U, info->offset) << "Failed verifying index " + std::to_string(i);
+ if (overlap1_index != 0 && i == overlap1_index) {
+ EXPECT_EQ(overlap1_name, info->name) << "Failed verifying overlap1 name " + std::to_string(i);
+ } else if (overlap2_index != 0 && i == overlap2_index) {
+ EXPECT_EQ(overlap2_name, info->name) << "Failed verifying overlap2 name " + std::to_string(i);
+ } else {
+ EXPECT_EQ("", info->name) << "Failed verifying index " + std::to_string(i);
+ }
+ }
+}
+
+TEST(MapsTest, file_should_fail) {
+ TemporaryFile tf;
+ ASSERT_TRUE(tf.fd != -1);
+
+ ASSERT_TRUE(android::base::WriteStringToFile(
+ "7ffff7dda000-7ffff7dfd7ffff7ff3000-7ffff7ff4000 ---p 0000f000 fc:02 44171565\n", tf.path,
+ 0660, getuid(), getgid()));
+
+ FileMaps maps(tf.path);
+
+ ASSERT_FALSE(maps.Parse());
+}
+
+// Create a maps file that is extremely large.
+TEST(MapsTest, large_file) {
+ TemporaryFile tf;
+ ASSERT_TRUE(tf.fd != -1);
+
+ std::string file_data;
+ uint64_t start = 0x700000;
+ for (size_t i = 0; i < 5000; i++) {
+ file_data +=
+ android::base::StringPrintf("%" PRIx64 "-%" PRIx64 " r-xp 1000 00:0 0 /fake%zu.so\n",
+ start + i * 4096, start + (i + 1) * 4096, i);
+ }
+
+ ASSERT_TRUE(android::base::WriteStringToFile(file_data, tf.path, 0660, getuid(), getgid()));
+
+ FileMaps maps(tf.path);
+
+ ASSERT_TRUE(maps.Parse());
+ ASSERT_EQ(5000U, maps.Total());
+ for (size_t i = 0; i < 5000; i++) {
+ MapInfo* info = maps.Get(i);
+ ASSERT_EQ(start + i * 4096, info->start) << "Failed at map " + std::to_string(i);
+ ASSERT_EQ(start + (i + 1) * 4096, info->end) << "Failed at map " + std::to_string(i);
+ std::string name = "/fake" + std::to_string(i) + ".so";
+ ASSERT_EQ(name, info->name) << "Failed at map " + std::to_string(i);
+ }
+}
+
TEST(MapsTest, find) {
BufferMaps maps(
"1000-2000 r--p 00000010 00:00 0 /system/lib/fake1.so\n"