Add method to get usage stats for a single map.
The new scudo allocator creates a huge map in 64 bit address space. Some
tests would get the usage stats of all maps, but only really cared about
a small set of maps. In this case, provide a method to only get the usage
stats for the maps you care about.
Test: Unit tests pass.
Change-Id: Ie845e47a8c789a57bf689c9f0e5878a921640e30
diff --git a/include/meminfo/procmeminfo.h b/include/meminfo/procmeminfo.h
index f782ec5..8c1280f 100644
--- a/include/meminfo/procmeminfo.h
+++ b/include/meminfo/procmeminfo.h
@@ -48,6 +48,10 @@
// 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.
//
diff --git a/libmeminfo_test.cpp b/libmeminfo_test.cpp
index cf5341d..378a4cd 100644
--- a/libmeminfo_test.cpp
+++ b/libmeminfo_test.cpp
@@ -101,6 +101,33 @@
}
}
+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();
diff --git a/procmeminfo.cpp b/procmeminfo.cpp
index 6f68ab4..9e9a705 100644
--- a/procmeminfo.cpp
+++ b/procmeminfo.cpp
@@ -244,6 +244,15 @@
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 @@
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 @@
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)) {
