libmeminfo: Add libmeminfo to gather global and per-process memory stats
The library is expected to be a unified place for all components to read
both global and per-process memory accounting form kernel including
getting the working set. This change adds the PageInfo, MemInfo and
ProcMemInfo classes and verifies the implementation against libpagemap
for correctness.
Adds a procmem2 tool show the usage.
TODO: Plumbing in os_debug, add vmastats, zoneinfo etc parsing.
Test: libmeminfo_test 1
Test: procmem2 1
Test: procmem2 -h -W 1
Test: procmem2 -h -w 1
Test: libmeminfo_benchmark
Bug: 111694435
Bug: 114325007
Change-Id: I280440b1dc26a498170686d10fcf63f953a0dcbd
Signed-off-by: Sandeep Patil <[email protected]>
diff --git a/pageacct.cpp b/pageacct.cpp
new file mode 100644
index 0000000..887a74d
--- /dev/null
+++ b/pageacct.cpp
@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <android-base/logging.h>
+#include <android-base/unique_fd.h>
+
+#include "meminfo_private.h"
+
+using unique_fd = ::android::base::unique_fd;
+
+namespace android {
+namespace meminfo {
+
+static inline off64_t pfn_to_idle_bitmap_offset(uint64_t pfn) {
+ return static_cast<off64_t>((pfn >> 6) << 3);
+}
+
+uint64_t pagesize(void) {
+ static uint64_t pagesize = sysconf(_SC_PAGE_SIZE);
+ return pagesize;
+}
+
+bool PageAcct::InitPageAcct(bool pageidle_enable) {
+ if (pageidle_enable && !PageAcct::KernelHasPageIdle()) {
+ LOG(ERROR) << "Idle page tracking is not supported by the kernel";
+ return false;
+ }
+
+ if (kpagecount_fd_ < 0) {
+ unique_fd count_fd(TEMP_FAILURE_RETRY(open("/proc/kpagecount", O_RDONLY | O_CLOEXEC)));
+ if (count_fd < 0) {
+ PLOG(ERROR) << "Failed to open /proc/kpagecount";
+ return false;
+ }
+ kpagecount_fd_ = std::move(count_fd);
+ }
+
+ if (kpageflags_fd_ < 0) {
+ unique_fd flags_fd(TEMP_FAILURE_RETRY(open("/proc/kpageflags", O_RDONLY | O_CLOEXEC)));
+ if (flags_fd < 0) {
+ PLOG(ERROR) << "Failed to open /proc/kpageflags";
+ return false;
+ }
+ kpageflags_fd_ = std::move(flags_fd);
+ }
+
+ if (pageidle_enable && pageidle_fd_ < 0) {
+ unique_fd idle_fd(
+ TEMP_FAILURE_RETRY(open("/sys/kernel/mm/page_idle/bitmap", O_RDWR | O_CLOEXEC)));
+ if (idle_fd < 0) {
+ PLOG(ERROR) << "Failed to open page idle bitmap";
+ return false;
+ }
+ pageidle_fd_ = std::move(idle_fd);
+ }
+
+ return true;
+}
+
+bool PageAcct::PageFlags(uint64_t pfn, uint64_t* flags) {
+ if (!flags) return false;
+
+ if (kpageflags_fd_ < 0) {
+ if (!InitPageAcct()) return false;
+ }
+
+ if (pread64(kpageflags_fd_, flags, sizeof(uint64_t), pfn * sizeof(uint64_t)) < 0) {
+ PLOG(ERROR) << "Failed to read page flags for page " << pfn;
+ return false;
+ }
+ return true;
+}
+
+bool PageAcct::PageMapCount(uint64_t pfn, uint64_t* mapcount) {
+ if (!mapcount) return false;
+
+ if (kpagecount_fd_ < 0) {
+ if (!InitPageAcct()) return false;
+ }
+
+ if (pread64(kpagecount_fd_, mapcount, sizeof(uint64_t), pfn * sizeof(uint64_t)) < 0) {
+ PLOG(ERROR) << "Failed to read map count for page " << pfn;
+ return false;
+ }
+ return true;
+}
+
+int PageAcct::IsPageIdle(uint64_t pfn) {
+ if (pageidle_fd_ < 0) {
+ if (!InitPageAcct(true)) return -EOPNOTSUPP;
+ }
+
+ int idle_status = MarkPageIdle(pfn);
+ if (idle_status) return idle_status;
+
+ return GetPageIdle(pfn);
+}
+
+int PageAcct::MarkPageIdle(uint64_t pfn) const {
+ off64_t offset = pfn_to_idle_bitmap_offset(pfn);
+ // set the bit corresponding to page frame
+ uint64_t idle_bits = 1ULL << (pfn % 64);
+
+ if (pwrite64(pageidle_fd_, &idle_bits, sizeof(uint64_t), offset) < 0) {
+ PLOG(ERROR) << "Failed to write page idle bitmap for page " << pfn;
+ return -errno;
+ }
+
+ return 0;
+}
+
+int PageAcct::GetPageIdle(uint64_t pfn) const {
+ off64_t offset = pfn_to_idle_bitmap_offset(pfn);
+ uint64_t idle_bits;
+
+ if (pread64(pageidle_fd_, &idle_bits, sizeof(uint64_t), offset) < 0) {
+ PLOG(ERROR) << "Failed to read page idle bitmap for page " << pfn;
+ return -errno;
+ }
+
+ return !!(idle_bits & (1ULL << (pfn % 64)));
+}
+
+} // namespace meminfo
+} // namespace android
