SERVER-33643 refactor processInfo to no longer depend on global

initialization.

11 files changed, 42 insertions, 64 deletions

diff --git a/src/mongo/util/clock_source_bm.cpp b/src/mongo/util/clock_source_bm.cpp
index 719471e976e..c64811210f3 100644
--- a/src/mongo/util/clock_source_bm.cpp
+++ b/src/mongo/util/clock_source_bm.cpp
@@ -69,12 +69,7 @@ void BM_ClockNow(benchmark::State& state) {
 }
 
 BENCHMARK(BM_ClockNow)
-    ->ThreadRange(1,
-                  [] {
-                      ProcessInfo::initializeSystemInfo();
-                      ProcessInfo pi;
-                      return static_cast<int>(pi.getNumAvailableCores().value_or(pi.getNumCores()));
-                  }())
+    ->ThreadRange(1, ProcessInfo::getNumAvailableCores())
     ->ArgName("poll period")
     ->Arg(0)
     ->Arg(1)
diff --git a/src/mongo/util/processinfo.cpp b/src/mongo/util/processinfo.cpp
index 987c9875406..fcd75b7daa3 100644
--- a/src/mongo/util/processinfo.cpp
+++ b/src/mongo/util/processinfo.cpp
@@ -92,22 +92,4 @@ private:
 bool writePidFile(const string& path) {
     return pidFileWiper.write(path);
 }
-
-ProcessInfo::SystemInfo* ProcessInfo::systemInfo = NULL;
-
-void ProcessInfo::initializeSystemInfo() {
-    if (systemInfo == NULL) {
-        systemInfo = new SystemInfo();
-    }
-}
-
-/**
- * We need this get the system page size for the secure allocator, which the enterprise modules need
- * for storage for command line parameters.
- */
-MONGO_INITIALIZER_GENERAL(SystemInfo, MONGO_NO_PREREQUISITES, MONGO_NO_DEPENDENTS)
-(InitializerContext* context) {
-    ProcessInfo::initializeSystemInfo();
-    return Status::OK();
-}
-}
+}  // namespace mongo
diff --git a/src/mongo/util/processinfo.h b/src/mongo/util/processinfo.h
index 0a2d2cc1d22..f02f1a78493 100644
--- a/src/mongo/util/processinfo.h
+++ b/src/mongo/util/processinfo.h
@@ -58,69 +58,71 @@ public:
     /**
      * Get the type of os (e.g. Windows, Linux, Mac OS)
      */
-    const std::string& getOsType() const {
+    static const std::string& getOsType() {
         return sysInfo().osType;
     }
 
     /**
      * Get the os Name (e.g. Ubuntu, Gentoo, Windows Server 2008)
      */
-    const std::string& getOsName() const {
+    static const std::string& getOsName() {
         return sysInfo().osName;
     }
 
     /**
      * Get the os version (e.g. 10.04, 11.3.0, 6.1 (build 7600))
      */
-    const std::string& getOsVersion() const {
+    static const std::string& getOsVersion() {
         return sysInfo().osVersion;
     }
 
     /**
      * Get the cpu address size (e.g. 32, 36, 64)
      */
-    unsigned getAddrSize() const {
+    static unsigned getAddrSize() {
         return sysInfo().addrSize;
     }
 
     /**
      * Get the total amount of system memory in MB
      */
-    unsigned long long getMemSizeMB() const {
+    static unsigned long long getMemSizeMB() {
         return sysInfo().memSize / (1024 * 1024);
     }
 
     /**
-     * Get the number of available CPUs. Depending on the OS, the number can be the
-     * number of available CPUs to the current process or scheduler.
+     * Get the number of CPUs
      */
-    boost::optional<unsigned long> getNumAvailableCores();
+    static unsigned getNumCores() {
+        return sysInfo().numCores;
+    }
 
     /**
-     * Get the number of CPUs
+     * Get the number of cores available. Make a best effort to get the cores for this process.
+     * If that information is not available, get the total number of CPUs.
      */
-    unsigned getNumCores() const {
-        return sysInfo().numCores;
+    static unsigned long getNumAvailableCores() {
+        return ProcessInfo::getNumCoresForProcess().value_or(ProcessInfo::getNumCores());
     }
 
     /**
      * Get the system page size in bytes.
      */
     static unsigned long long getPageSize() {
-        return systemInfo->pageSize;
+        return sysInfo().pageSize;
     }
 
     /**
      * Get the CPU architecture (e.g. x86, x86_64)
      */
-    const std::string& getArch() const {
+    static const std::string& getArch() {
         return sysInfo().cpuArch;
     }
 
     /**
      * Determine if NUMA is enabled (interleaved) for this process
      */
-    bool hasNumaEnabled() const {
+    static bool hasNumaEnabled() {
         return sysInfo().hasNuma;
     }
 
@@ -128,14 +130,14 @@ public:
      * Determine if file zeroing is necessary for newly allocated data files.
      */
     static bool isDataFileZeroingNeeded() {
-        return systemInfo->fileZeroNeeded;
+        return sysInfo().fileZeroNeeded;
     }
 
     /**
      * Determine if we need to workaround slow msync performance on Illumos/Solaris
      */
     static bool preferMsyncOverFSync() {
-        return systemInfo->preferMsyncOverFSync;
+        return sysInfo().preferMsyncOverFSync;
     }
 
     /**
@@ -236,18 +238,20 @@ private:
     };
 
     ProcessId _pid;
-    static stdx::mutex _sysInfoLock;
 
     static bool checkNumaEnabled();
 
-    static ProcessInfo::SystemInfo* systemInfo;
-
-    inline const SystemInfo& sysInfo() const {
-        return *systemInfo;
+    inline static const SystemInfo& sysInfo() {
+        static ProcessInfo::SystemInfo systemInfo;
+        return systemInfo;
     }
 
-public:
-    static void initializeSystemInfo();
+private:
+    /**
+     * Get the number of available CPUs. Depending on the OS, the number can be the
+     * number of available CPUs to the current process or scheduler.
+     */
+    static boost::optional<unsigned long> getNumCoresForProcess();
 };
 
 bool writePidFile(const std::string& path);
diff --git a/src/mongo/util/processinfo_freebsd.cpp b/src/mongo/util/processinfo_freebsd.cpp
index ce07c514753..3041d0f4387 100644
--- a/src/mongo/util/processinfo_freebsd.cpp
+++ b/src/mongo/util/processinfo_freebsd.cpp
@@ -195,7 +195,7 @@ bool ProcessInfo::pagesInMemory(const void* start, size_t numPages, vector<char>
 }
 
 // get the number of CPUs available to the scheduler
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     long nprocs = sysconf(_SC_NPROCESSORS_ONLN);
     if (nprocs)
         return nprocs;
diff --git a/src/mongo/util/processinfo_linux.cpp b/src/mongo/util/processinfo_linux.cpp
index 0c014a5e9a4..5db07c94661 100644
--- a/src/mongo/util/processinfo_linux.cpp
+++ b/src/mongo/util/processinfo_linux.cpp
@@ -424,7 +424,7 @@ bool ProcessInfo::supported() {
 }
 
 // get the number of CPUs available to the current process
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     cpu_set_t set;
 
     if (sched_getaffinity(0, sizeof(cpu_set_t), &set) == 0) {
diff --git a/src/mongo/util/processinfo_openbsd.cpp b/src/mongo/util/processinfo_openbsd.cpp
index a4c1d0f9ab2..7db5cb4e908 100644
--- a/src/mongo/util/processinfo_openbsd.cpp
+++ b/src/mongo/util/processinfo_openbsd.cpp
@@ -214,7 +214,7 @@ bool ProcessInfo::pagesInMemory(const void* start, size_t numPages, vector<char>
 }
 
 // get the number of CPUs available to the scheduler
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     long nprocs = sysconf(_SC_NPROCESSORS_ONLN);
     if (nprocs)
         return nprocs;
diff --git a/src/mongo/util/processinfo_osx.cpp b/src/mongo/util/processinfo_osx.cpp
index 475016de313..f244bea4da9 100644
--- a/src/mongo/util/processinfo_osx.cpp
+++ b/src/mongo/util/processinfo_osx.cpp
@@ -64,7 +64,7 @@ bool ProcessInfo::supported() {
 }
 
 // get the number of CPUs available to the scheduler
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     long nprocs = sysconf(_SC_NPROCESSORS_ONLN);
     if (nprocs)
         return nprocs;
diff --git a/src/mongo/util/processinfo_solaris.cpp b/src/mongo/util/processinfo_solaris.cpp
index 3bd892de4e8..26ff218d90c 100644
--- a/src/mongo/util/processinfo_solaris.cpp
+++ b/src/mongo/util/processinfo_solaris.cpp
@@ -110,7 +110,7 @@ bool ProcessInfo::supported() {
 }
 
 // get the number of CPUs available to the scheduler
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     long nprocs = sysconf(_SC_NPROCESSORS_ONLN);
     if (nprocs)
         return nprocs;
diff --git a/src/mongo/util/processinfo_test.cpp b/src/mongo/util/processinfo_test.cpp
index 76f7e7ee551..53bf5305b51 100644
--- a/src/mongo/util/processinfo_test.cpp
+++ b/src/mongo/util/processinfo_test.cpp
@@ -55,18 +55,13 @@ TEST(ProcessInfo, NonZeroPageSize) {
 TEST(ProcessInfo, GetNumAvailableCores) {
 #if defined(__APPLE__) || defined(__linux__) || (defined(__sun) && defined(__SVR4)) || \
     defined(_WIN32)
-    ProcessInfo processInfo;
-    ProcessInfo::initializeSystemInfo();
-    optional<unsigned long> numAvailCores = processInfo.getNumAvailableCores();
-    ASSERT_TRUE(numAvailCores.is_initialized());
-    ASSERT_GREATER_THAN(*numAvailCores, 0u);
-    ASSERT_LESS_THAN_OR_EQUALS(*numAvailCores, processInfo.getNumCores());
+    unsigned long numAvailCores = ProcessInfo::getNumAvailableCores();
+    ASSERT_GREATER_THAN(numAvailCores, 0u);
+    ASSERT_LESS_THAN_OR_EQUALS(numAvailCores, ProcessInfo::getNumCores());
 #endif
 }
 
 TEST(ProcessInfo, GetNumCoresReturnsNonZeroNumberOfProcessors) {
-    ProcessInfo processInfo;
-    ProcessInfo::initializeSystemInfo();
-    ASSERT_GREATER_THAN(processInfo.getNumCores(), 0u);
+    ASSERT_GREATER_THAN(ProcessInfo::getNumCores(), 0u);
 }
 }
diff --git a/src/mongo/util/processinfo_windows.cpp b/src/mongo/util/processinfo_windows.cpp
index 676204c9856..7aba688d2df 100644
--- a/src/mongo/util/processinfo_windows.cpp
+++ b/src/mongo/util/processinfo_windows.cpp
@@ -77,7 +77,7 @@ ProcessInfo::ProcessInfo(ProcessId pid) {}
 ProcessInfo::~ProcessInfo() {}
 
 // get the number of CPUs available to the current process
-boost::optional<unsigned long> ProcessInfo::getNumAvailableCores() {
+boost::optional<unsigned long> ProcessInfo::getNumCoresForProcess() {
     DWORD_PTR process_mask, system_mask;
 
     if (GetProcessAffinityMask(GetCurrentProcess(), &process_mask, &system_mask)) {
@@ -464,6 +464,8 @@ bool ProcessInfo::checkNumaEnabled() {
 }
 
 bool ProcessInfo::blockCheckSupported() {
+    sysInfo();  // Initialize SystemInfo, which calls collectSystemInfo(), which creates
+                // psapiGlobal.
     return psapiGlobal->supported;
 }
 
diff --git a/src/mongo/util/tcmalloc_set_parameter.cpp b/src/mongo/util/tcmalloc_set_parameter.cpp
index ca9cf7eb108..1ec424e1490 100644
--- a/src/mongo/util/tcmalloc_set_parameter.cpp
+++ b/src/mongo/util/tcmalloc_set_parameter.cpp
@@ -129,7 +129,7 @@ TcmallocNumericPropertyServerParameter tcmallocAggressiveMemoryDecommit(
     "tcmallocAggressiveMemoryDecommit", "tcmalloc.aggressive_memory_decommit");
 
 MONGO_INITIALIZER_GENERAL(TcmallocConfigurationDefaults,
-                          ("SystemInfo"),
+                          MONGO_NO_PREREQUISITES,
                           ("BeginStartupOptionHandling"))
 (InitializerContext*) {
     // Before processing the command line options, if the user has not specified a value in via