SERVER-4740 Don't use unsigned for time deltas

Leads to weird bugs when time goes backwards.

This commit doesn't resolve SERVER-4740 (Use monotonic clock sources for
Timer) but lessens the impact of using a non-monotonic clock.

15 files changed, 47 insertions, 46 deletions

diff --git a/src/mongo/db/catalog/collection_cursor_cache.cpp b/src/mongo/db/catalog/collection_cursor_cache.cpp
index 4ff28aa3a71..926baf7a137 100644
--- a/src/mongo/db/catalog/collection_cursor_cache.cpp
+++ b/src/mongo/db/catalog/collection_cursor_cache.cpp
@@ -102,7 +102,7 @@ namespace mongo {
 
         void appendStats( BSONObjBuilder& builder );
 
-        std::size_t timeoutCursors( unsigned millisSinceLastCall );
+        std::size_t timeoutCursors( int millisSinceLastCall );
 
         int64_t nextSeed();
 
@@ -204,7 +204,7 @@ namespace mongo {
         return collection->cursorCache()->eraseCursor( id, checkAuth );
     }
 
-    std::size_t GlobalCursorIdCache::timeoutCursors( unsigned millisSinceLastCall ) {
+    std::size_t GlobalCursorIdCache::timeoutCursors( int millisSinceLastCall ) {
         vector<string> todo;
         {
             SimpleMutex::scoped_lock lk( _mutex );
@@ -235,7 +235,7 @@ namespace mongo {
 
     // ---
 
-    std::size_t CollectionCursorCache::timeoutCursorsGlobal( unsigned millisSinceLastCall ) {
+    std::size_t CollectionCursorCache::timeoutCursorsGlobal( int millisSinceLastCall ) {
         return _globalCursorIdCache.timeoutCursors( millisSinceLastCall );
     }
 
@@ -365,7 +365,7 @@ namespace mongo {
         }
     }
 
-    std::size_t CollectionCursorCache::timeoutCursors( unsigned millisSinceLastCall ) {
+    std::size_t CollectionCursorCache::timeoutCursors( int millisSinceLastCall ) {
         SimpleMutex::scoped_lock lk( _mutex );
 
         vector<ClientCursor*> toDelete;
diff --git a/src/mongo/db/catalog/collection_cursor_cache.h b/src/mongo/db/catalog/collection_cursor_cache.h
index 284d303391f..bc057def73f 100644
--- a/src/mongo/db/catalog/collection_cursor_cache.h
+++ b/src/mongo/db/catalog/collection_cursor_cache.h
@@ -72,7 +72,7 @@ namespace mongo {
          * note: must have a readlock on the collection
          * @return number timed out
          */
-        std::size_t timeoutCursors( unsigned millisSinceLastCall );
+        std::size_t timeoutCursors( int millisSinceLastCall );
 
         // -----------------
 
@@ -117,7 +117,7 @@ namespace mongo {
         /**
          * @return number timed out
          */
-        static std::size_t timeoutCursorsGlobal( unsigned millisSinceLastCall );
+        static std::size_t timeoutCursorsGlobal( int millisSinceLastCall );
 
     private:
         CursorId _allocateCursorId_inlock();
diff --git a/src/mongo/db/clientcursor.cpp b/src/mongo/db/clientcursor.cpp
index 5fa3654bfa8..628c4e110b7 100644
--- a/src/mongo/db/clientcursor.cpp
+++ b/src/mongo/db/clientcursor.cpp
@@ -152,12 +152,12 @@ namespace mongo {
     // Timing and timeouts
     //
 
-    bool ClientCursor::shouldTimeout(unsigned millis) {
+    bool ClientCursor::shouldTimeout(int millis) {
         _idleAgeMillis += millis;
         return _idleAgeMillis > 600000 && _pinValue == 0;
     }
 
-    void ClientCursor::setIdleTime( unsigned millis ) {
+    void ClientCursor::setIdleTime( int millis ) {
         _idleAgeMillis = millis;
     }
 
diff --git a/src/mongo/db/clientcursor.h b/src/mongo/db/clientcursor.h
index ca8aa95ca23..ae6640fa39f 100644
--- a/src/mongo/db/clientcursor.h
+++ b/src/mongo/db/clientcursor.h
@@ -89,9 +89,9 @@ namespace mongo {
          * @param millis amount of idle passed time since last call
          * note called outside of locks (other than ccmutex) so care must be exercised
          */
-        bool shouldTimeout( unsigned millis );
-        void setIdleTime( unsigned millis );
-        unsigned idleTime() const { return _idleAgeMillis; }
+        bool shouldTimeout( int millis );
+        void setIdleTime( int millis );
+        int idleTime() const { return _idleAgeMillis; }
 
         uint64_t getLeftoverMaxTimeMicros() const { return _leftoverMaxTimeMicros; }
         void setLeftoverMaxTimeMicros( uint64_t leftoverMaxTimeMicros ) {
@@ -184,7 +184,7 @@ namespace mongo {
         OpTime _slaveReadTill;
 
         // How long has the cursor been idle?
-        unsigned _idleAgeMillis;
+        int _idleAgeMillis;
 
         // TODO: Document.
         uint64_t _leftoverMaxTimeMicros;
diff --git a/src/mongo/db/curop.h b/src/mongo/db/curop.h
index 9459b482bca..fa90d2322d9 100644
--- a/src/mongo/db/curop.h
+++ b/src/mongo/db/curop.h
@@ -255,7 +255,7 @@ namespace mongo {
 
         void ensureStarted();
         bool isStarted() const { return _start > 0; }
-        unsigned long long startTime() { // micros
+        long long startTime() { // micros
             ensureStarted();
             return _start;
         }
@@ -264,12 +264,12 @@ namespace mongo {
             _end = curTimeMicros64();
         }
 
-        unsigned long long totalTimeMicros() {
+        long long totalTimeMicros() {
             massert( 12601 , "CurOp not marked done yet" , ! _active );
             return _end - startTime();
         }
         int totalTimeMillis() { return (int) (totalTimeMicros() / 1000); }
-        unsigned long long elapsedMicros() {
+        long long elapsedMicros() {
             return curTimeMicros64() - startTime();
         }
         int elapsedMillis() {
@@ -326,8 +326,8 @@ namespace mongo {
         Client * _client;
         CurOp * _wrapped;
         Command * _command;
-        unsigned long long _start;
-        unsigned long long _end;
+        long long _start;
+        long long _end;
         bool _active;
         bool _suppressFromCurop; // unless $all is set
         int _op;
diff --git a/src/mongo/db/storage/mmap_v1/dur_stats.h b/src/mongo/db/storage/mmap_v1/dur_stats.h
index d97c48d5a39..2a0c98e544c 100644
--- a/src/mongo/db/storage/mmap_v1/dur_stats.h
+++ b/src/mongo/db/storage/mmap_v1/dur_stats.h
@@ -51,10 +51,10 @@ namespace mongo {
                 unsigned long long _uncompressedBytes;
                 unsigned long long _writeToDataFilesBytes;
 
-                unsigned long long _prepLogBufferMicros;
-                unsigned long long _writeToJournalMicros;
-                unsigned long long _writeToDataFilesMicros;
-                unsigned long long _remapPrivateViewMicros;
+                long long _prepLogBufferMicros;
+                long long _writeToJournalMicros;
+                long long _writeToDataFilesMicros;
+                long long _remapPrivateViewMicros;
 
                 // undesirable to be in write lock for the group commit (it can be done in a read lock), so good if we
                 // have visibility when this happens.  can happen for a couple reasons
@@ -63,7 +63,7 @@ namespace mongo {
                 // - data being written faster than the normal group commit interval
                 unsigned _commitsInWriteLock;
 
-                unsigned _dtMillis;
+                int _dtMillis;
             };
             S *curr;
         private:
diff --git a/src/mongo/db/storage/mmap_v1/dur_writetodatafiles.cpp b/src/mongo/db/storage/mmap_v1/dur_writetodatafiles.cpp
index 02b2bf5bb44..1fbb80c2253 100644
--- a/src/mongo/db/storage/mmap_v1/dur_writetodatafiles.cpp
+++ b/src/mongo/db/storage/mmap_v1/dur_writetodatafiles.cpp
@@ -104,7 +104,7 @@ namespace mongo {
 #endif
             Timer t;
             WRITETODATAFILES_Impl1(h, uncompressed);
-            unsigned long long m = t.micros();
+            long long m = t.micros();
             stats.curr->_writeToDataFilesMicros += m;
             LOG(2) << "journal WRITETODATAFILES " << m / 1000.0 << "ms" << endl;
         }
diff --git a/src/mongo/dbtests/perftests.cpp b/src/mongo/dbtests/perftests.cpp
index 749d40b39f5..b88269aff90 100644
--- a/src/mongo/dbtests/perftests.cpp
+++ b/src/mongo/dbtests/perftests.cpp
@@ -196,7 +196,7 @@ namespace PerfTests {
     public:
         virtual unsigned batchSize() { return 50; }
 
-        void say(unsigned long long n, int us, string s) {
+        void say(unsigned long long n, long long us, string s) {
             unsigned long long rps = (n*1000*1000)/(us > 0 ? us : 1);
             cout << "stats " << setw(42) << left << s << ' ' << right << setw(9) << rps << ' ' << right << setw(5) << us/1000 << "ms ";
             if( showDurStats() )
@@ -316,7 +316,7 @@ namespace PerfTests {
                     for( i = 0; i < Batch; i++ )
                         timed();
                     n += i;
-                } while( t.micros() < (unsigned) hlm * 1000 );
+                } while( t.micros() < (hlm * 1000) );
             }
 
             client().getLastError(); // block until all ops are finished
diff --git a/src/mongo/dbtests/querytests.cpp b/src/mongo/dbtests/querytests.cpp
index ff062057250..0f834d1d50c 100644
--- a/src/mongo/dbtests/querytests.cpp
+++ b/src/mongo/dbtests/querytests.cpp
@@ -1242,7 +1242,8 @@ namespace QueryTests {
 
             ASSERT( ! Helpers::findById( ctx.ctx().db(), ns() , BSON( "_id" << 200 ) , res ) );
 
-            unsigned long long slow , fast;
+            long long slow;
+            long long fast;
 
             int n = 10000;
             DEV n = 1000;
diff --git a/src/mongo/scripting/bench.h b/src/mongo/scripting/bench.h
index fb78380dcd6..83f674896bb 100644
--- a/src/mongo/scripting/bench.h
+++ b/src/mongo/scripting/bench.h
@@ -151,7 +151,7 @@ namespace mongo {
         /**
          * Count one instance of the event, which took "timeMicros" microseconds.
          */
-        void countOne(unsigned long long timeMicros) {
+        void countOne(long long timeMicros) {
             ++_numEvents;
             _totalTimeMicros += timeMicros;
         }
@@ -168,7 +168,7 @@ namespace mongo {
 
     private:
         unsigned long long _numEvents;
-        unsigned long long _totalTimeMicros;
+        long long _totalTimeMicros;
     };
 
     /**
diff --git a/src/mongo/util/timer-generic-inl.h b/src/mongo/util/timer-generic-inl.h
index 67672d206e2..c0b07c563d7 100644
--- a/src/mongo/util/timer-generic-inl.h
+++ b/src/mongo/util/timer-generic-inl.h
@@ -44,6 +44,6 @@
 
 namespace mongo {
 
-    unsigned long long Timer::now() const { return curTimeMicros64(); }
+    long long Timer::now() const { return curTimeMicros64(); }
 
 }  // namespace mongo
diff --git a/src/mongo/util/timer-posixclock-inl.h b/src/mongo/util/timer-posixclock-inl.h
index b0aeddedf01..a171c25ab0d 100644
--- a/src/mongo/util/timer-posixclock-inl.h
+++ b/src/mongo/util/timer-posixclock-inl.h
@@ -41,17 +41,17 @@
 
 namespace mongo {
 
-    unsigned long long Timer::now() const {
+    long long Timer::now() const {
         timespec the_time;
-        unsigned long long result;
+        long long result;
 
         fassert(16160, !clock_gettime(CLOCK_MONOTONIC, &the_time));
 
         // Safe for 292 years after the clock epoch, even if we switch to a signed time value.  On
         // Linux, the monotonic clock's epoch is the UNIX epoch.
-        result = static_cast<unsigned long long>(the_time.tv_sec);
+        result = static_cast<long long>(the_time.tv_sec);
         result *= nanosPerSecond;
-        result += static_cast<unsigned long long>(the_time.tv_nsec);
+        result += static_cast<long long>(the_time.tv_nsec);
         return result;
     }
 
diff --git a/src/mongo/util/timer-win32-inl.h b/src/mongo/util/timer-win32-inl.h
index b78f6389be0..dedf77ca385 100644
--- a/src/mongo/util/timer-win32-inl.h
+++ b/src/mongo/util/timer-win32-inl.h
@@ -45,7 +45,7 @@
 
 namespace mongo {
 
-    unsigned long long Timer::now() const {
+    long long Timer::now() const {
         LARGE_INTEGER i;
         fassert(16161, QueryPerformanceCounter(&i));
         return i.QuadPart;
diff --git a/src/mongo/util/timer.cpp b/src/mongo/util/timer.cpp
index c5cddc96cd7..597c4e15aa5 100644
--- a/src/mongo/util/timer.cpp
+++ b/src/mongo/util/timer.cpp
@@ -34,7 +34,7 @@
 namespace mongo {
 
     // default value of 1 so that during startup initialization if referenced no division by zero
-    unsigned long long Timer::_countsPerSecond = 1;
+    long long Timer::_countsPerSecond = 1;
 
     namespace {
 
@@ -59,11 +59,11 @@ namespace mongo {
 
             // Make sure that the current time relative to the (unspecified) epoch isn't already too
             // big to represent as a 64-bit count of nanoseconds.
-            unsigned long long maxSecs = std::numeric_limits<unsigned long long>::max() /
+            long long maxSecs = std::numeric_limits<long long>::max() /
                 Timer::nanosPerSecond;
             timespec the_time;
             fassert(16162, !clock_gettime(CLOCK_MONOTONIC, &the_time));
-            fassert(16163, static_cast<unsigned long long>(the_time.tv_sec) < maxSecs);
+            fassert(16163, static_cast<long long>(the_time.tv_sec) < maxSecs);
         }
 
 #elif defined(MONGO_TIMER_IMPL_GENERIC)
diff --git a/src/mongo/util/timer.h b/src/mongo/util/timer.h
index 161bc98ecb9..0d5a5e97ebc 100644
--- a/src/mongo/util/timer.h
+++ b/src/mongo/util/timer.h
@@ -46,9 +46,9 @@ namespace mongo {
      */
     class MONGO_CLIENT_API Timer /*copyable*/ {
     public:
-        static const unsigned long long millisPerSecond = 1000;
-        static const unsigned long long microsPerSecond = 1000 * millisPerSecond;
-        static const unsigned long long nanosPerSecond = 1000 * microsPerSecond;
+        static const long long millisPerSecond = 1000;
+        static const long long microsPerSecond = 1000 * millisPerSecond;
+        static const long long nanosPerSecond = 1000 * microsPerSecond;
 
         Timer() { reset(); }
         int seconds() const { return (int)(micros() / 1000000); }
@@ -60,15 +60,15 @@ namespace mongo {
          *  @return time in milliseconds.
          */
         inline int millisReset() {
-            unsigned long long nextNow = now();
-            unsigned long long deltaMicros =
+            const long long nextNow = now();
+            const long long deltaMicros =
                 ((nextNow - _old) * microsPerSecond) / _countsPerSecond;
 
             _old = nextNow;
             return static_cast<int>(deltaMicros / 1000);
         }
 
-        inline unsigned long long micros() const {
+        inline long long micros() const {
             return ((now() - _old) * microsPerSecond) / _countsPerSecond;
         }
 
@@ -82,12 +82,12 @@ namespace mongo {
          * This value is initialized at program startup, and never changed after.
          * It should be treated as private.
          */
-        static unsigned long long _countsPerSecond;
+        static long long _countsPerSecond;
 
     private:
-        inline unsigned long long now() const;
+        inline long long now() const;
 
-        unsigned long long _old;
+        long long _old;
     };
 }  // namespace mongo