Merge "Add method to get usage stats for a single map." (d1cb35bd) · Commits · e / os / android_system_core

libmeminfo/include/meminfo/procmeminfo.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -48,6 +48,10 @@ class ProcMemInfo final {
		// Same as Maps() except, do not read the usage stats for each map.
		const std::vector<Vma>& MapsWithoutUsageStats();

		// If MapsWithoutUsageStats was called, this function will fill in
		// usage stats for this single vma.
		bool FillInVmaStats(Vma& vma);

		// Collect all 'vma' or 'maps' from /proc/<pid>/smaps and store them in 'maps_'. Returns a
		// constant reference to the vma vector after the collection is done.
		//

libmeminfo/libmeminfo_test.cpp

+27 −0

Original line number	Diff line number	Diff line
		@@ -101,6 +101,33 @@ TEST(ProcMemInfo, MapsUsageEmpty) {
		}
		}

		TEST(ProcMemInfo, MapsUsageFillInLater) {
		ProcMemInfo proc_mem(pid);
		const std::vector<Vma>& maps = proc_mem.MapsWithoutUsageStats();
		EXPECT_FALSE(maps.empty());
		for (auto& map : maps) {
		Vma update_map(map);
		ASSERT_EQ(map.start, update_map.start);
		ASSERT_EQ(map.end, update_map.end);
		ASSERT_EQ(map.offset, update_map.offset);
		ASSERT_EQ(map.flags, update_map.flags);
		ASSERT_EQ(map.name, update_map.name);
		ASSERT_EQ(0, update_map.usage.vss);
		ASSERT_EQ(0, update_map.usage.rss);
		ASSERT_EQ(0, update_map.usage.pss);
		ASSERT_EQ(0, update_map.usage.uss);
		ASSERT_EQ(0, update_map.usage.swap);
		ASSERT_EQ(0, update_map.usage.swap_pss);
		ASSERT_EQ(0, update_map.usage.private_clean);
		ASSERT_EQ(0, update_map.usage.private_dirty);
		ASSERT_EQ(0, update_map.usage.shared_clean);
		ASSERT_EQ(0, update_map.usage.shared_dirty);
		ASSERT_TRUE(proc_mem.FillInVmaStats(update_map));
		// Check that at least one usage stat was updated.
		ASSERT_NE(0, update_map.usage.vss);
		}
		}

		TEST(ProcMemInfo, PageMapPresent) {
		static constexpr size_t kNumPages = 20;
		size_t pagesize = getpagesize();

libmeminfo/procmeminfo.cpp

+25 −5

Original line number	Diff line number	Diff line
		@@ -244,6 +244,15 @@ bool ProcMemInfo::PageMap(const Vma& vma, std::vector<uint64_t>* pagemap) {
		return true;
		}

		static int GetPagemapFd(pid_t pid) {
		std::string pagemap_file = ::android::base::StringPrintf("/proc/%d/pagemap", pid);
		int fd = TEMP_FAILURE_RETRY(open(pagemap_file.c_str(), O_RDONLY \| O_CLOEXEC));
		if (fd == -1) {
		PLOG(ERROR) << "Failed to open " << pagemap_file;
		}
		return fd;
		}

		bool ProcMemInfo::ReadMaps(bool get_wss, bool use_pageidle, bool get_usage_stats) {
		// Each object reads /proc/<pid>/maps only once. This is done to make sure programs that are
		// running for the lifetime of the system can recycle the objects and don't have to
		@@ -269,11 +278,8 @@ bool ProcMemInfo::ReadMaps(bool get_wss, bool use_pageidle, bool get_usage_stats
		return true;
		}

		std::string pagemap_file = ::android::base::StringPrintf("/proc/%d/pagemap", pid_);
		::android::base::unique_fd pagemap_fd(
		TEMP_FAILURE_RETRY(open(pagemap_file.c_str(), O_RDONLY \| O_CLOEXEC)));
		if (pagemap_fd < 0) {
		PLOG(ERROR) << "Failed to open " << pagemap_file;
		::android::base::unique_fd pagemap_fd(GetPagemapFd(pid_));
		if (pagemap_fd == -1) {
		return false;
		}

		@@ -290,6 +296,20 @@ bool ProcMemInfo::ReadMaps(bool get_wss, bool use_pageidle, bool get_usage_stats
		return true;
		}

		bool ProcMemInfo::FillInVmaStats(Vma& vma) {
		::android::base::unique_fd pagemap_fd(GetPagemapFd(pid_));
		if (pagemap_fd == -1) {
		return false;
		}

		if (!ReadVmaStats(pagemap_fd.get(), vma, get_wss_, false)) {
		LOG(ERROR) << "Failed to read page map for vma " << vma.name << "[" << vma.start << "-"
		<< vma.end << "]";
		return false;
		}
		return true;
		}

		bool ProcMemInfo::ReadVmaStats(int pagemap_fd, Vma& vma, bool get_wss, bool use_pageidle) {
		PageAcct& pinfo = PageAcct::Instance();
		if (get_wss && use_pageidle && !pinfo.InitPageAcct(true)) {