support pid option in pcm

Author: rdementi

src/cpucounters.cpp

@@ -2390,7 +2390,7 @@ perf_event_attr PCM_init_perf_event_attr(bool group = true)
 }
 #endif
 
-PCM::ErrorCode PCM::program(const PCM::ProgramMode mode_, const void * parameter_, const bool silent)
+PCM::ErrorCode PCM::program(const PCM::ProgramMode mode_, const void * parameter_, const bool silent, const int pid)
 {
 #ifdef __linux__
     if (isNMIWatchdogEnabled(silent))
@@ -2689,6 +2689,11 @@ PCM::ErrorCode PCM::program(const PCM::ProgramMode mode_, const void * parameter
             << core_fixed_counter_num_max << " available\n";
         return PCM::UnknownError;
     }
+    if (pid != -1 && canUsePerf == false)
+    {
+        std::cerr << "PCM ERROR: pid monitoring is only supported with Linux perf_event driver\n";
+        return PCM::UnknownError;
+    }
 
     programmed_pmu = true;
 
@@ -2703,11 +2708,11 @@ PCM::ErrorCode PCM::program(const PCM::ProgramMode mode_, const void * parameter
     {
         if (isCoreOnline(i) == false) continue;
 
-        std::packaged_task<void()> task([this, i, mode_, pExtDesc, &programmingStatuses]() -> void
+        std::packaged_task<void()> task([this, i, mode_, pExtDesc, &programmingStatuses, &pid]() -> void
             {
                 TemporalThreadAffinity tempThreadAffinity(i, false); // speedup trick for Linux
 
-                programmingStatuses[i] = programCoreCounters(i, mode_, pExtDesc, lastProgrammedCustomCounters[i]);
+                programmingStatuses[i] = programCoreCounters(i, mode_, pExtDesc, lastProgrammedCustomCounters[i], pid);
             });
         asyncCoreResults.push_back(task.get_future());
         coreTaskQueues[i]->push(task);
@@ -2807,8 +2812,10 @@ std::mutex printErrorMutex;
 PCM::ErrorCode PCM::programCoreCounters(const int i /* core */,
     const PCM::ProgramMode mode_,
     const ExtendedCustomCoreEventDescription * pExtDesc,
-    std::vector<EventSelectRegister> & result)
+    std::vector<EventSelectRegister> & result,
+    const int pid)
 {
+    (void) pid; // to silence uused param warning on non Linux OS
     // program core counters
 
     result.clear();
@@ -2840,10 +2847,10 @@ PCM::ErrorCode PCM::programCoreCounters(const int i /* core */,
     };
 #ifdef PCM_USE_PERF
     int leader_counter = -1;
-    auto programPerfEvent = [this, &leader_counter, &i](perf_event_attr & e, const int eventPos, const std::string & eventName) -> bool
+    auto programPerfEvent = [this, &leader_counter, &i, &pid](perf_event_attr & e, const int eventPos, const std::string & eventName) -> bool
     {
         // if (i == 0) std::cerr << "DEBUG: programming event "<< std::hex << e.config << std::dec << "\n";
-        if ((perfEventHandle[i][eventPos] = syscall(SYS_perf_event_open, &e, -1,
+        if ((perfEventHandle[i][eventPos] = syscall(SYS_perf_event_open, &e, pid,
             i /* core id */, leader_counter /* group leader */, 0)) <= 0)
         {
             std::lock_guard<std::mutex> _(printErrorMutex);

src/cpucounters.h

@@ -894,7 +894,7 @@ class PCM_API PCM
     std::vector<std::vector<EventSelectRegister> > lastProgrammedCustomCounters;
     uint32 checkCustomCoreProgramming(std::shared_ptr<SafeMsrHandle> msr);
     ErrorCode programCoreCounters(int core, const PCM::ProgramMode mode, const ExtendedCustomCoreEventDescription * pExtDesc,
-        std::vector<EventSelectRegister> & programmedCustomCounters);
+        std::vector<EventSelectRegister> & programmedCustomCounters, const int pid);
 
     bool PMUinUse();
     void cleanupPMU(const bool silent = false);
@@ -1110,6 +1110,8 @@ class PCM_API PCM
     /*! \brief Programs performance counters
         \param mode_ mode of programming, see ProgramMode definition
         \param parameter_ optional parameter for some of programming modes
+        \param silent set to true to silence diagnostic messages
+        \param pid restrict core metrics only to specified pid (process id)
 
                 Call this method before you start using the performance counting routines.
 
@@ -1118,7 +1120,7 @@ class PCM_API PCM
         program PMUs: Intel(r) VTune(tm), Intel(r) Performance Tuning Utility (PTU). This code may make
         VTune or PTU measurements invalid. VTune or PTU measurement may make measurement with this code invalid. Please enable either usage of these routines or VTune/PTU/etc.
     */
-    ErrorCode program(const ProgramMode mode_ = DEFAULT_EVENTS, const void * parameter_ = NULL, const bool silent = false); // program counters and start counting
+    ErrorCode program(const ProgramMode mode_ = DEFAULT_EVENTS, const void * parameter_ = NULL, const bool silent = false, const int pid = -1); // program counters and start counting
 
     /*! \brief checks the error and suggests solution and/or exits the process
         \param code error code from the 'program' call

src/pcm.cpp

@@ -88,6 +88,7 @@ void print_help(const string prog_name)
     cerr << "                                        will read counters only after external program finishes\n";
     cerr << " Supported <options> are: \n";
     cerr << "  -h    | --help      | /h           => print this help and exit\n";
+    cerr << "  -pid PID | /pid PID                => collect core metrics only for specified process ID\n";
 #ifdef _MSC_VER
     cerr << "  --uninstallDriver   | --installDriver=> (un)install driver\n";
 #endif
@@ -1155,7 +1156,7 @@ int main(int argc, char * argv[])
     // if delay is not specified: use either default (1 second),
     // or only read counters before or after PCM started: keep PCM blocked
     double delay = -1.0;
-
+    int pid{-1};
     char *sysCmd = NULL;
     char **sysArgv = NULL;
     bool show_core_output = true;
@@ -1166,6 +1167,8 @@ int main(int argc, char * argv[])
     bool reset_pmu = false;
     bool disable_JKT_workaround = false; // as per http://software.intel.com/en-us/articles/performance-impact-when-sampling-certain-llc-events-on-snb-ep-with-vtune
 
+    parseParam(argc, argv, "pid", [&pid](const char* p) { if (p) pid = atoi(p); });
+
     MainLoop mainLoop;
     std::bitset<MAX_CORES> ycores;
     string program = string(argv[0]);
@@ -1259,6 +1262,12 @@ int main(int argc, char * argv[])
             }
             continue;
         }
+        else if (strncmp(*argv, "-pid", 4) == 0 || strncmp(*argv, "/pid", 4) == 0)
+        {
+            argv++;
+            argc--;
+            continue;
+        }
         else
         if (mainLoop.parseArg(*argv))
         {
@@ -1342,7 +1351,7 @@ int main(int argc, char * argv[])
     }
 
     // program() creates common semaphore for the singleton, so ideally to be called before any other references to PCM
-    PCM::ErrorCode status = m->program();
+    const PCM::ErrorCode status = m->program(PCM::DEFAULT_EVENTS, nullptr, false, pid);
 
     switch (status)
     {
@@ -1367,6 +1376,11 @@ int main(int argc, char * argv[])
     SystemCounterState sstate1, sstate2;
     const auto cpu_model = m->getCPUModel();
 
+    if (pid != -1)
+    {
+        cerr << "Collecting core metrics for process ID " << pid << "\n";
+    }
+
     if ((sysCmd != NULL) && (delay <= 0.0)) {
         // in case external command is provided in command line, and
         // delay either not provided (-1) or is zero

src/utils.h

@@ -307,6 +307,11 @@ void parseParam(int argc, char* argv[], const char* param, F f)
         {
             argv++;
             argc--;
+            if (argc == 0)
+            {
+                std::cerr << "ERROR: no parameter provided for option " << param << "\n";
+                exit(EXIT_FAILURE);
+            }
             f(*argv);
             continue;
         }