Merge branch 'smalinux-CtrTime'

25 files changed, 220 insertions, 87 deletions

diff --git a/ClockMeter.c b/ClockMeter.c
index 410c7e8a..f8a447e9 100644
--- a/ClockMeter.c
+++ b/ClockMeter.c
@@ -20,9 +20,10 @@ static const int ClockMeter_attributes[] = {
 };
 
 static void ClockMeter_updateValues(Meter* this) {
-   time_t t = time(NULL);
+   const ProcessList* pl = this->pl;
+
    struct tm result;
-   const struct tm* lt = localtime_r(&t, &result);
+   const struct tm* lt = localtime_r(&pl->realtime.tv_sec, &result);
    this->values[0] = lt->tm_hour * 60 + lt->tm_min;
    strftime(this->txtBuffer, sizeof(this->txtBuffer), "%H:%M:%S", lt);
 }
diff --git a/Compat.c b/Compat.c
index 55be1b1d..43d02ec7 100644
--- a/Compat.c
+++ b/Compat.c
@@ -11,18 +11,12 @@ in the source distribution for its full text.
 
 #include <errno.h>
 #include <fcntl.h> // IWYU pragma: keep
-#include <time.h>
 #include <unistd.h>
 #include <sys/stat.h>
 #include <sys/types.h> // IWYU pragma: keep
 
 #include "XUtils.h" // IWYU pragma: keep
 
-#ifdef HAVE_HOST_GET_CLOCK_SERVICE
-#include <mach/clock.h>
-#include <mach/mach.h>
-#endif
-
 
 int Compat_faccessat(int dirfd,
                      const char* pathname,
@@ -123,31 +117,3 @@ ssize_t Compat_readlinkat(int dirfd,
 
 #endif
 }
-
-int Compat_clock_monotonic_gettime(struct timespec *tp) {
-
-#if defined(HAVE_CLOCK_GETTIME)
-
-   return clock_gettime(CLOCK_MONOTONIC, tp);
-
-#elif defined(HAVE_HOST_GET_CLOCK_SERVICE)
-
-   clock_serv_t cclock;
-   mach_timespec_t mts;
-
-   host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
-   clock_get_time(cclock, &mts);
-   mach_port_deallocate(mach_task_self(), cclock);
-
-   tp->tv_sec = mts.tv_sec;
-   tp->tv_nsec = mts.tv_nsec;
-
-   return 0;
-
-#else
-
-#error No Compat_clock_monotonic_gettime() implementation!
-
-#endif
-
-}
diff --git a/Compat.h b/Compat.h
index 95947351..94c2ee2f 100644
--- a/Compat.h
+++ b/Compat.h
@@ -56,6 +56,4 @@ ssize_t Compat_readlinkat(int dirfd,
                           char* buf,
                           size_t bufsize);
 
-int Compat_clock_monotonic_gettime(struct timespec *tp);
-
 #endif /* HEADER_Compat */
diff --git a/DateMeter.c b/DateMeter.c
index ac653b62..520e516a 100644
--- a/DateMeter.c
+++ b/DateMeter.c
@@ -20,9 +20,10 @@ static const int DateMeter_attributes[] = {
 };
 
 static void DateMeter_updateValues(Meter* this) {
-   time_t t = time(NULL);
+   const ProcessList* pl = this->pl;
+
    struct tm result;
-   const struct tm* lt = localtime_r(&t, &result);
+   const struct tm* lt = localtime_r(&pl->realtime.tv_sec, &result);
    this->values[0] = lt->tm_yday;
    int year = lt->tm_year + 1900;
    if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) {
diff --git a/DateTimeMeter.c b/DateTimeMeter.c
index 3fb515b5..588b9fbe 100644
--- a/DateTimeMeter.c
+++ b/DateTimeMeter.c
@@ -20,9 +20,10 @@ static const int DateTimeMeter_attributes[] = {
 };
 
 static void DateTimeMeter_updateValues(Meter* this) {
-   time_t t = time(NULL);
+   const ProcessList* pl = this->pl;
+
    struct tm result;
-   const struct tm* lt = localtime_r(&t, &result);
+   const struct tm* lt = localtime_r(&pl->realtime.tv_sec, &result);
    int year = lt->tm_year + 1900;
    if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) {
       this->total = 366;
diff --git a/DiskIOMeter.c b/DiskIOMeter.c
index dde007ed..dd2e3c46 100644
--- a/DiskIOMeter.c
+++ b/DiskIOMeter.c
@@ -31,12 +31,10 @@ static uint32_t cached_write_diff;
 static double cached_utilisation_diff;
 
 static void DiskIOMeter_updateValues(Meter* this) {
-   static uint64_t cached_last_update;
+   const ProcessList* pl = this->pl;
 
-   struct timeval tv;
-   gettimeofday(&tv, NULL);
-   uint64_t timeInMilliSeconds = (uint64_t)tv.tv_sec * 1000 + (uint64_t)tv.tv_usec / 1000;
-   uint64_t passedTimeInMs = timeInMilliSeconds - cached_last_update;
+   static uint64_t cached_last_update;
+   uint64_t passedTimeInMs = pl->realtimeMs - cached_last_update;
 
    /* update only every 500ms */
    if (passedTimeInMs > 500) {
@@ -45,7 +43,7 @@ static void DiskIOMeter_updateValues(Meter* this) {
       static uint64_t cached_msTimeSpend_total;
       uint64_t diff;
 
-      cached_last_update = timeInMilliSeconds;
+      cached_last_update = pl->realtimeMs;
 
       DiskIOData data;
 
diff --git a/Makefile.am b/Makefile.am
index f587eeb0..f9b9a7d4 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -134,6 +134,7 @@ myhtopheaders = \
 # -----
 
 linux_platform_headers = \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/uname.h \
 	linux/HugePageMeter.h \
@@ -154,6 +155,7 @@ linux_platform_headers = \
 	zfs/ZfsCompressedArcMeter.h
 
 linux_platform_sources = \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/uname.c \
 	linux/HugePageMeter.c \
@@ -184,6 +186,7 @@ freebsd_platform_headers = \
 	freebsd/FreeBSDProcess.h \
 	freebsd/Platform.h \
 	freebsd/ProcessField.h \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/openzfs_sysctl.h \
 	generic/uname.h \
@@ -195,6 +198,7 @@ freebsd_platform_sources = \
 	freebsd/Platform.c \
 	freebsd/FreeBSDProcessList.c \
 	freebsd/FreeBSDProcess.c \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/openzfs_sysctl.c \
 	generic/uname.c \
@@ -215,6 +219,7 @@ dragonflybsd_platform_headers = \
 	dragonflybsd/DragonFlyBSDProcess.h \
 	dragonflybsd/Platform.h \
 	dragonflybsd/ProcessField.h \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/uname.h
 
@@ -222,6 +227,7 @@ dragonflybsd_platform_sources = \
 	dragonflybsd/DragonFlyBSDProcessList.c \
 	dragonflybsd/DragonFlyBSDProcess.c \
 	dragonflybsd/Platform.c \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/uname.c
 
@@ -235,6 +241,7 @@ endif
 # -------
 
 openbsd_platform_headers = \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/uname.h \
 	openbsd/OpenBSDProcessList.h \
@@ -243,6 +250,7 @@ openbsd_platform_headers = \
 	openbsd/ProcessField.h
 
 openbsd_platform_sources = \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/uname.c \
 	openbsd/OpenBSDProcessList.c \
@@ -263,6 +271,7 @@ darwin_platform_headers = \
 	darwin/DarwinProcessList.h \
 	darwin/Platform.h \
 	darwin/ProcessField.h \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/openzfs_sysctl.h \
 	generic/uname.h \
@@ -274,6 +283,7 @@ darwin_platform_sources = \
 	darwin/Platform.c \
 	darwin/DarwinProcess.c \
 	darwin/DarwinProcessList.c \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/openzfs_sysctl.c \
 	generic/uname.c \
@@ -291,6 +301,7 @@ endif
 # -------
 
 solaris_platform_headers = \
+	generic/gettime.h \
 	generic/hostname.h \
 	generic/uname.h \
 	solaris/ProcessField.h \
@@ -302,6 +313,7 @@ solaris_platform_headers = \
 	zfs/ZfsCompressedArcMeter.h
 
 solaris_platform_sources = \
+	generic/gettime.c \
 	generic/hostname.c \
 	generic/uname.c \
 	solaris/Platform.c \
@@ -320,12 +332,14 @@ endif
 # -----------
 
 unsupported_platform_headers = \
+	generic/gettime.h \
 	unsupported/Platform.h \
 	unsupported/ProcessField.h \
 	unsupported/UnsupportedProcess.h \
 	unsupported/UnsupportedProcessList.h
 
 unsupported_platform_sources = \
+	generic/gettime.c \
 	unsupported/Platform.c \
 	unsupported/UnsupportedProcess.c \
 	unsupported/UnsupportedProcessList.c
diff --git a/Meter.c b/Meter.c
index 6aa9f08e..13df763a 100644
--- a/Meter.c
+++ b/Meter.c
@@ -18,6 +18,7 @@ in the source distribution for its full text.
 #include "CRT.h"
 #include "Macros.h"
 #include "Object.h"
+#include "Platform.h"
 #include "ProvideCurses.h"
 #include "RichString.h"
 #include "Settings.h"
@@ -286,6 +287,7 @@ static const char* const GraphMeterMode_dotsAscii[] = {
 };
 
 static void GraphMeterMode_draw(Meter* this, int x, int y, int w) {
+   const ProcessList* pl = this->pl;
 
    if (!this->drawData) {
       this->drawData = xCalloc(1, sizeof(GraphData));
@@ -312,12 +314,10 @@ static void GraphMeterMode_draw(Meter* this, int x, int y, int w) {
    x += captionLen;
    w -= captionLen;
 
-   struct timeval now;
-   gettimeofday(&now, NULL);
-   if (!timercmp(&now, &(data->time), <)) {
+   if (!timercmp(&pl->realtime, &(data->time), <)) {
       int globalDelay = this->pl->settings->delay;
       struct timeval delay = { .tv_sec = globalDelay / 10, .tv_usec = (globalDelay - ((globalDelay / 10) * 10)) * 100000 };
-      timeradd(&now, &delay, &(data->time));
+      timeradd(&pl->realtime, &delay, &(data->time));
 
       for (int i = 0; i < nValues - 1; i++)
          data->values[i] = data->values[i + 1];
diff --git a/NetworkIOMeter.c b/NetworkIOMeter.c
index c0e1b06f..84fc12db 100644
--- a/NetworkIOMeter.c
+++ b/NetworkIOMeter.c
@@ -25,12 +25,10 @@ static uint32_t cached_txb_diff;
 static uint32_t cached_txp_diff;
 
 static void NetworkIOMeter_updateValues(Meter* this) {
+   const ProcessList* pl = this->pl;
    static uint64_t cached_last_update = 0;
 
-   struct timeval tv;
-   gettimeofday(&tv, NULL);
-   uint64_t timeInMilliSeconds = (uint64_t)tv.tv_sec * 1000 + (uint64_t)tv.tv_usec / 1000;
-   uint64_t passedTimeInMs = timeInMilliSeconds - cached_last_update;
+   uint64_t passedTimeInMs = pl->realtimeMs - cached_last_update;
 
    /* update only every 500ms */
    if (passedTimeInMs > 500) {
@@ -40,7 +38,7 @@ static void NetworkIOMeter_updateValues(Meter* this) {
       static uint64_t cached_txp_total;
       uint64_t diff;
 
-      cached_last_update = timeInMilliSeconds;
+      cached_last_update = pl->realtimeMs;
 
       NetworkIOData data;
       hasData = Platform_getNetworkIO(&data);
diff --git a/Process.c b/Process.c
index b67ad445..6eecddfc 100644
--- a/Process.c
+++ b/Process.c
@@ -467,14 +467,14 @@ void Process_toggleTag(Process* this) {
 
 bool Process_isNew(const Process* this) {
    assert(this->processList);
-   if (this->processList->scanTs >= this->seenTs) {
-      return this->processList->scanTs - this->seenTs <= 1000 * this->processList->settings->highlightDelaySecs;
+   if (this->processList->monotonicMs >= this->seenStampMs) {
+      return this->processList->monotonicMs - this->seenStampMs <= 1000 * (uint64_t)this->processList->settings->highlightDelaySecs;
    }
    return false;
 }
 
 bool Process_isTomb(const Process* this) {
-    return this->tombTs > 0;
+    return this->tombStampMs > 0;
 }
 
 bool Process_setPriority(Process* this, int priority) {
diff --git a/Process.h b/Process.h
index e9c42622..72197963 100644
--- a/Process.h
+++ b/Process.h
@@ -174,8 +174,8 @@ typedef struct Process_ {
    /*
     * Internal time counts for showing new and exited processes.
     */
-   time_t seenTs;
-   time_t tombTs;
+   uint64_t seenStampMs;
+   uint64_t tombStampMs;
 
    /*
     * Internal state for tree-mode.
diff --git a/ProcessList.c b/ProcessList.c
index cd8ebd8a..6bc15611 100644
--- a/ProcessList.c
+++ b/ProcessList.c
@@ -10,11 +10,12 @@ in the source distribution for its full text.
 #include <assert.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/time.h>
 
-#include "Compat.h"
 #include "CRT.h"
 #include "Hashtable.h"
 #include "Macros.h"
+#include "Platform.h"
 #include "Vector.h"
 #include "XUtils.h"
 
@@ -35,7 +36,7 @@ ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, Users
    // set later by platform-specific code
    this->cpuCount = 0;
 
-   this->scanTs = 0;
+   this->monotonicMs = 0;
 
 #ifdef HAVE_LIBHWLOC
    this->topologyOk = false;
@@ -131,7 +132,7 @@ void ProcessList_add(ProcessList* this, Process* p) {
    p->processList = this;
 
    // highlighting processes found in first scan by first scan marked "far in the past"
-   p->seenTs = this->scanTs;
+   p->seenStampMs = this->monotonicMs;
 
    Vector_add(this->processes, p);
    Hashtable_put(this->processTable, p->pid, p);
@@ -582,8 +583,6 @@ Process* ProcessList_getProcess(ProcessList* this, pid_t pid, bool* preExisting,
 }
 
 void ProcessList_scan(ProcessList* this, bool pauseProcessUpdate) {
-   struct timespec now;
-
    // in pause mode only gather global data for meters (CPU/memory/...)
    if (pauseProcessUpdate) {
       ProcessList_goThroughEntries(this, true);
@@ -604,31 +603,29 @@ void ProcessList_scan(ProcessList* this, bool pauseProcessUpdate) {
    this->runningTasks = 0;
 
 
-   // set scanTs
+   // set scan timestamp
    static bool firstScanDone = false;
-   if (!firstScanDone) {
-      this->scanTs = 0;
+   if (firstScanDone) {
+      Platform_gettime_monotonic(&this->monotonicMs);
+   } else {
+      this->monotonicMs = 0;
       firstScanDone = true;
-   } else if (Compat_clock_monotonic_gettime(&now) == 0) {
-      // save time in millisecond, so with a delay in deciseconds
-      // there are no irregularities
-      this->scanTs = 1000 * now.tv_sec + now.tv_nsec / 1000000;
    }
 
    ProcessList_goThroughEntries(this, false);
 
    for (int i = Vector_size(this->processes) - 1; i >= 0; i--) {
       Process* p = (Process*) Vector_get(this->processes, i);
-      if (p->tombTs > 0) {
+      if (p->tombStampMs > 0) {
          // remove tombed process
-         if (this->scanTs >= p->tombTs) {
+         if (this->monotonicMs >= p->tombStampMs) {
             ProcessList_remove(this, p);
          }
       } else if (p->updated == false) {
          // process no longer exists
          if (this->settings->highlightChanges && p->wasShown) {
             // mark tombed
-            p->tombTs = this->scanTs + 1000 * this->settings->highlightDelaySecs;
+            p->tombStampMs = this->monotonicMs + 1000 * this->settings->highlightDelaySecs;
          } else {
             // immediately remove
             ProcessList_remove(this, p);
diff --git a/ProcessList.h b/ProcessList.h
index 3d9b8ff2..7d98197d 100644
--- a/ProcessList.h
+++ b/ProcessList.h
@@ -48,6 +48,10 @@ typedef struct ProcessList_ {
    Hashtable* displayTreeSet;
    Hashtable* draftingTreeSet;
 
+   struct timeval realtime;   /* time of the current sample */
+   uint64_t realtimeMs;       /* current time in milliseconds */
+   uint64_t monotonicMs;      /* same, but from monotonic clock */
+
    Panel* panel;
    int following;
    uid_t userId;
@@ -76,8 +80,6 @@ typedef struct ProcessList_ {
    memory_t cachedSwap;
 
    unsigned int cpuCount;
-
-   time_t scanTs;
 } ProcessList;
 
 ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId);
diff --git a/ScreenManager.c b/ScreenManager.c
index 17a76bf3..6e7551fe 100644
--- a/ScreenManager.c
+++ b/ScreenManager.c
@@ -15,6 +15,7 @@ in the source distribution for its full text.
 #include "CRT.h"
 #include "FunctionBar.h"
 #include "Object.h"
+#include "Platform.h"
 #include "ProcessList.h"
 #include "ProvideCurses.h"
 #include "XUtils.h"
@@ -92,9 +93,8 @@ void ScreenManager_resize(ScreenManager* this, int x1, int y1, int x2, int y2) {
 static void checkRecalculation(ScreenManager* this, double* oldTime, int* sortTimeout, bool* redraw, bool* rescan, bool* timedOut) {
    ProcessList* pl = this->header->pl;
 
-   struct timeval tv;
-   gettimeofday(&tv, NULL);
-   double newTime = ((double)tv.tv_sec * 10) + ((double)tv.tv_usec / 100000);
+   Platform_gettime_realtime(&pl->realtime, &pl->realtimeMs);
+   double newTime = ((double)pl->realtime.tv_sec * 10) + ((double)pl->realtime.tv_usec / 100000);
 
    *timedOut = (newTime - *oldTime > this->settings->delay);
    *rescan |= *timedOut;
diff --git a/darwin/Platform.c b/darwin/Platform.c
index 3842fddc..ca8df611 100644
--- a/darwin/Platform.c
+++ b/darwin/Platform.c
@@ -37,6 +37,10 @@ in the source distribution for its full text.
 #include "zfs/ZfsArcMeter.h"
 #include "zfs/ZfsCompressedArcMeter.h"
 
+#ifdef HAVE_HOST_GET_CLOCK_SERVICE
+#include <mach/clock.h>
+#include <mach/mach.h>
+#endif
 #ifdef HAVE_MACH_MACH_TIME_H
 #include <mach/mach_time.h>
 #endif
@@ -405,3 +409,23 @@ void Platform_getBattery(double* percent, ACPresence* isOnAC) {
    CFRelease(list);
    CFRelease(power_sources);
 }
+
+void Platform_gettime_monotonic(uint64_t* msec) {
+
+#ifdef HAVE_HOST_GET_CLOCK_SERVICE
+
+   clock_serv_t cclock;
+   mach_timespec_t mts;
+
+   host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
+   clock_get_time(cclock, &mts);
+   mach_port_deallocate(mach_task_self(), cclock);
+
+   *msec = ((uint64_t)mts.tv_sec * 1000) + ((uint64_t)mts.tv_nsec / 1000000);
+
+#else
+
+   Generic_gettime_monotomic(msec);
+
+#endif
+}
diff --git a/darwin/Platform.h b/darwin/Platform.h
index 7bce9b35..902d27ef 100644
--- a/darwin/Platform.h
+++ b/darwin/Platform.h
@@ -19,6 +19,7 @@ in the source distribution for its full text.
 #include "NetworkIOMeter.h"
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -85,4 +86,10 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+void Platform_gettime_monotonic(uint64_t* msec);
+
 #endif
diff --git a/dragonflybsd/Platform.h b/dragonflybsd/Platform.h
index 993768be..87c124d9 100644
--- a/dragonflybsd/Platform.h
+++ b/dragonflybsd/Platform.h
@@ -17,6 +17,7 @@ in the source distribution for its full text.
 #include "NetworkIOMeter.h"
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -75,4 +76,12 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif
diff --git a/freebsd/Platform.h b/freebsd/Platform.h
index 884b7634..a0ec6abe 100644
--- a/freebsd/Platform.h
+++ b/freebsd/Platform.h
@@ -18,6 +18,7 @@ in the source distribution for its full text.
 #include "Process.h"
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -80,4 +81,12 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif
diff --git a/generic/gettime.c b/generic/gettime.c
new file mode 100644
index 00000000..ef7d2290
--- /dev/null
+++ b/generic/gettime.c
@@ -0,0 +1,57 @@
+/*
+htop - generic/gettime.c
+(C) 2021 htop dev team
+Released under the GNU GPLv2, see the COPYING file
+in the source distribution for its full text.
+*/
+#include "config.h"  // IWYU pragma: keep
+
+#include <string.h>
+#include <time.h>
+
+#include "generic/gettime.h"
+
+
+void Generic_gettime_realtime(struct timeval* tvp, uint64_t* msec) {
+
+#if defined(HAVE_CLOCK_GETTIME)
+
+   struct timespec ts;
+   if (clock_gettime(CLOCK_REALTIME, &ts) == 0) {
+      tvp->tv_sec = ts.tv_sec;
+      tvp->tv_usec = ts.tv_nsec / 1000;
+      *msec = ((uint64_t)ts.tv_sec * 1000) + ((uint64_t)ts.tv_nsec / 1000000);
+   } else {
+      memset(tvp, 0, sizeof(struct timeval));
+      *msec = 0;
+   }
+
+#else	/* lower resolution gettimeofday(2) is always available */
+
+   struct timeval tv;
+   if (gettimeofday(&tv, NULL) == 0) {
+      *tsp = tv; /* struct copy */
+      *msec = ((uint64_t)tv.tv_sec * 1000) + ((uint64_t)tv.tv_usec / 1000);
+   } else {
+      memset(tvp, 0, sizeof(struct timeval));
+      *msec = 0;
+   }
+
+#endif
+}
+
+void Generic_gettime_monotonic(uint64_t* msec) {
+#if defined(HAVE_CLOCK_GETTIME)
+
+   struct timespec ts;
+   if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
+      *msec = ((uint64_t)ts.tv_sec * 1000) + ((uint64_t)ts.tv_nsec / 1000000);
+   else
+      *msec = 0;
+
+#else
+
+# error "No monotonic clock available"
+
+#endif
+}
diff --git a/generic/gettime.h b/generic/gettime.h
new file mode 100644
index 00000000..fab33da1
--- /dev/null
+++ b/generic/gettime.h
@@ -0,0 +1,19 @@
+#ifndef HEADER_gettime
+#define HEADER_gettime
+/*
+htop - generic/gettime.h
+(C) 2021 htop dev team
+Released under the GNU GPLv2, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include <stdint.h>
+#include <sys/time.h>
+#include <sys/types.h>
+
+
+void Generic_gettime_realtime(struct timeval* ts, uint64_t* msec);
+
+void Generic_gettime_monotonic(uint64_t* msec);
+
+#endif
diff --git a/linux/LinuxProcessList.c b/linux/LinuxProcessList.c
index b12a415b..0c0fd16c 100644
--- a/linux/LinuxProcessList.c
+++ b/linux/LinuxProcessList.c
@@ -1989,10 +1989,6 @@ void ProcessList_goThroughEntries(ProcessList* super, bool pauseProcessUpdate) {
       return;
    }
 
-   struct timeval tv;
-   gettimeofday(&tv, NULL);
-   unsigned long long now = tv.tv_sec * 1000ULL + tv.tv_usec / 1000ULL;
-
    /* PROCDIR is an absolute path */
    assert(PROCDIR[0] == '/');
 #ifdef HAVE_OPENAT
@@ -2001,5 +1997,5 @@ void ProcessList_goThroughEntries(ProcessList* super, bool pauseProcessUpdate) {
    openat_arg_t rootFd = "";
 #endif
 
-   LinuxProcessList_recurseProcTree(this, rootFd, PROCDIR, NULL, period, now);
+   LinuxProcessList_recurseProcTree(this, rootFd, PROCDIR, NULL, period, super->realtimeMs);
 }
diff --git a/linux/Platform.h b/linux/Platform.h
index 18d303d1..78a44275 100644
--- a/linux/Platform.h
+++ b/linux/Platform.h
@@ -19,6 +19,7 @@ in the source distribution for its full text.
 #include "Process.h"
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -93,4 +94,12 @@ void Platform_longOptionsUsage(const char* name);
 
 bool Platform_getLongOption(int opt, int argc, char** argv);
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif
diff --git a/openbsd/Platform.h b/openbsd/Platform.h
index f54b0509..18e1a1c0 100644
--- a/openbsd/Platform.h
+++ b/openbsd/Platform.h
@@ -19,6 +19,7 @@ in the source distribution for its full text.
 #include "Process.h"
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -78,4 +79,12 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif
diff --git a/solaris/Platform.h b/solaris/Platform.h
index cca857bc..47fa3727 100644
--- a/solaris/Platform.h
+++ b/solaris/Platform.h
@@ -26,6 +26,7 @@ in the source distribution for its full text.
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
 
+#include "generic/gettime.h"
 #include "generic/hostname.h"
 #include "generic/uname.h"
 
@@ -101,4 +102,12 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif
diff --git a/unsupported/Platform.h b/unsupported/Platform.h
index 2331e278..849a6861 100644
--- a/unsupported/Platform.h
+++ b/unsupported/Platform.h
@@ -15,6 +15,7 @@ in the source distribution for its full text.
 #include "ProcessLocksScreen.h"
 #include "SignalsPanel.h"
 #include "UnsupportedProcess.h"
+#include "generic/gettime.h"
 
 
 extern const SignalItem Platform_signals[];
@@ -69,4 +70,12 @@ static inline bool Platform_getLongOption(ATTR_UNUSED int opt, ATTR_UNUSED int a
    return false;
 }
 
+static inline void Platform_gettime_realtime(struct timeval* tv, uint64_t* msec) {
+    Generic_gettime_realtime(tv, msec);
+}
+
+static inline void Platform_gettime_monotonic(uint64_t* msec) {
+    Generic_gettime_monotonic(msec);
+}
+
 #endif