tvl-depot/users/multi/pkgs/htop/zfs-arc-stats/0005-Refactor-common-OpenZFS-sysctl-access.patch

From a88d2e313df7f5f2b781d5b14ffe0e7710018c10 Mon Sep 17 00:00:00 2001
From: Ross Williams <ross@ross-williams.net>
Date: Sun, 7 Jul 2019 23:27:00 +0000
Subject: [PATCH 5/9] Refactor common OpenZFS sysctl access

Darwin and FreeBSD export zfs kstats through the
same APIs, so moving functions into a common file.
---
 Makefile.am                  | 21 ++++-----
 darwin/DarwinProcessList.c   | 82 +++---------------------------------
 darwin/DarwinProcessList.h   | 11 +----
 darwin/Platform.c            | 14 +++---
 darwin/Platform.h            |  2 +-
 freebsd/FreeBSDProcessList.c | 77 +++++----------------------------
 freebsd/FreeBSDProcessList.h | 14 ++----
 freebsd/Platform.c           | 14 +++---
 linux/LinuxProcessList.c     | 40 ++++++++----------
 linux/LinuxProcessList.h     | 10 +----
 linux/Platform.c             | 14 +++---
 zfs/ZfsArcStats.c            | 19 +++++++++
 zfs/ZfsArcStats.h            | 23 ++++++++++
 zfs/openzfs_sysctl.c         | 81 +++++++++++++++++++++++++++++++++++
 zfs/openzfs_sysctl.h         | 18 ++++++++
 15 files changed, 216 insertions(+), 224 deletions(-)
 create mode 100644 zfs/ZfsArcStats.c
 create mode 100644 zfs/ZfsArcStats.h
 create mode 100644 zfs/openzfs_sysctl.c
 create mode 100644 zfs/openzfs_sysctl.h

diff --git a/Makefile.am b/Makefile.am
index b6d2117..5eee631 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -36,10 +36,6 @@ TasksMeter.h UptimeMeter.h TraceScreen.h UsersTable.h Vector.h Process.h \
 AffinityPanel.h HostnameMeter.h OpenFilesScreen.h Affinity.h IncSet.h Action.h \
 EnvScreen.h InfoScreen.h XAlloc.h
 
-zfs_platform_sources = zfs/ZfsArcMeter.c
-
-zfs_platform_headers = zfs/ZfsArcMeter.h
-
 all_platform_headers =
 
 # Linux
@@ -53,7 +49,8 @@ linux_platform_headers = \
 	linux/LinuxProcessList.h \
 	linux/LinuxCRT.h \
 	linux/Battery.h \
-	$(zfs_platform_headers)
+	zfs/ZfsArcMeter.h \
+	zfs/ZfsArcStats.h
 
 all_platform_headers += $(linux_platform_headers)
 
@@ -61,7 +58,7 @@ if HTOP_LINUX
 AM_CFLAGS += -rdynamic
 myhtopplatsources = linux/Platform.c linux/IOPriorityPanel.c linux/IOPriority.c \
 linux/LinuxProcess.c linux/LinuxProcessList.c linux/LinuxCRT.c linux/Battery.c \
-$(zfs_platform_sources)
+zfs/ZfsArcMeter.c zfs/ZfsArcStats.c
 
 myhtopplatheaders = $(linux_platform_headers)
 endif
@@ -75,14 +72,16 @@ freebsd_platform_headers = \
 	freebsd/FreeBSDProcess.h \
 	freebsd/FreeBSDCRT.h \
 	freebsd/Battery.h \
-	$(zfs_platform_headers)
+	zfs/ZfsArcMeter.h \
+	zfs/ZfsArcStats.h \
+	zfs/openzfs_sysctl.h
 
 all_platform_headers += $(freebsd_platform_headers)
 
 if HTOP_FREEBSD
 myhtopplatsources = freebsd/Platform.c freebsd/FreeBSDProcessList.c \
 freebsd/FreeBSDProcess.c freebsd/FreeBSDCRT.c freebsd/Battery.c \
-$(zfs_platform_sources)
+zfs/ZfsArcMeter.c zfs/ZfsArcStats.c zfs/openzfs_sysctl.c
 
 myhtopplatheaders = $(freebsd_platform_headers)
 endif
@@ -135,7 +134,9 @@ darwin_platform_headers = \
 	darwin/DarwinProcessList.h \
 	darwin/DarwinCRT.h \
 	darwin/Battery.h \
-	$(zfs_platform_headers)
+	zfs/ZfsArcMeter.h \
+	zfs/ZfsArcStats.h \
+	zfs/openzfs_sysctl.h
 
 all_platform_headers += $(darwin_platform_headers)
 
@@ -143,7 +144,7 @@ if HTOP_DARWIN
 AM_LDFLAGS += -framework IOKit -framework CoreFoundation
 myhtopplatsources = darwin/Platform.c darwin/DarwinProcess.c \
 darwin/DarwinProcessList.c darwin/DarwinCRT.c darwin/Battery.c \
-$(zfs_platform_sources)
+zfs/ZfsArcMeter.c zfs/ZfsArcStats.c zfs/openzfs_sysctl.c
 
 myhtopplatheaders = $(darwin_platform_headers)
 endif
diff --git a/darwin/DarwinProcessList.c b/darwin/DarwinProcessList.c
index 267e8e9..122e018 100644
--- a/darwin/DarwinProcessList.c
+++ b/darwin/DarwinProcessList.c
@@ -9,6 +9,8 @@ in the source distribution for its full text.
 #include "DarwinProcess.h"
 #include "DarwinProcessList.h"
 #include "CRT.h"
+#include "zfs/ZfsArcStats.h"
+#include "zfs/openzfs_sysctl.h"
 
 #include <stdlib.h>
 #include <string.h>
@@ -69,27 +71,11 @@ typedef struct DarwinProcessList_ {
    uint64_t user_threads;
    uint64_t global_diff;
 
-   int zfsArcEnabled;
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcSize;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zfsArcAnon;
-   unsigned long long int zfsArcHeader;
-   unsigned long long int zfsArcOther;
-
+   ZfsArcStats zfs;
 } DarwinProcessList;
 
 }*/
 
-static int MIB_kstat_zfs_misc_arcstats_c_max[5];
-static int MIB_kstat_zfs_misc_arcstats_size[5];
-static int MIB_kstat_zfs_misc_arcstats_mfu_size[5];
-static int MIB_kstat_zfs_misc_arcstats_mru_size[5];
-static int MIB_kstat_zfs_misc_arcstats_anon_size[5];
-static int MIB_kstat_zfs_misc_arcstats_hdr_size[5];
-static int MIB_kstat_zfs_misc_arcstats_other_size[5];
-
 void ProcessList_getHostInfo(host_basic_info_data_t *p) {
    mach_msg_type_number_t info_size = HOST_BASIC_INFO_COUNT;
 
@@ -150,48 +136,6 @@ struct kinfo_proc *ProcessList_getKInfoProcs(size_t *count) {
    return processes;
 }
 
-static inline void DarwinProcessList_scanZfsArcstats(DarwinProcessList* dpl) {
-   size_t len;
-
-   if (dpl->zfsArcEnabled) {
-      len = sizeof(dpl->zfsArcSize);
-      sysctl(MIB_kstat_zfs_misc_arcstats_size, 5, &(dpl->zfsArcSize), &len , NULL, 0);
-      /* TODO: adjust reported memory in use to move ARC from wired to inactive
-         Like:
-         // In bytes
-         dpl->vm_stats.wire_count -= dpl->zfsArcSize / vm_page_size;
-         dpl->vm_stats.inactive_count += dpl->zfsArcSize / vm_page_size;
-         // Would purgable_count be more true?
-         // Then convert to KB:
-      */
-      dpl->zfsArcSize /= 1024;
-
-      len = sizeof(dpl->zfsArcMax);
-      sysctl(MIB_kstat_zfs_misc_arcstats_c_max, 5, &(dpl->zfsArcMax), &len , NULL, 0);
-      dpl->zfsArcMax /= 1024;
-
-      len = sizeof(dpl->zfsArcMFU);
-      sysctl(MIB_kstat_zfs_misc_arcstats_mfu_size, 5, &(dpl->zfsArcMFU), &len , NULL, 0);
-      dpl->zfsArcMFU /= 1024;
-
-      len = sizeof(dpl->zfsArcMRU);
-      sysctl(MIB_kstat_zfs_misc_arcstats_mru_size, 5, &(dpl->zfsArcMRU), &len , NULL, 0);
-      dpl->zfsArcMRU /= 1024;
-
-      len = sizeof(dpl->zfsArcAnon);
-      sysctl(MIB_kstat_zfs_misc_arcstats_anon_size, 5, &(dpl->zfsArcAnon), &len , NULL, 0);
-      dpl->zfsArcAnon /= 1024;
-
-      len = sizeof(dpl->zfsArcHeader);
-      sysctl(MIB_kstat_zfs_misc_arcstats_hdr_size, 5, &(dpl->zfsArcHeader), &len , NULL, 0);
-      dpl->zfsArcHeader /= 1024;
-
-      len = sizeof(dpl->zfsArcOther);
-      sysctl(MIB_kstat_zfs_misc_arcstats_other_size, 5, &(dpl->zfsArcOther), &len , NULL, 0);
-      dpl->zfsArcOther /= 1024;
-   }
-}
-
 ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList, uid_t userId) {
    size_t len;
    DarwinProcessList* this = xCalloc(1, sizeof(DarwinProcessList));
@@ -207,22 +151,8 @@ ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList, ui
    ProcessList_getVMStats(&this->vm_stats);
 
    /* Initialize the ZFS kstats, if zfs.kext loaded */
-   len = sizeof(this->zfsArcSize);
-   if (sysctlbyname("kstat.zfs.misc.arcstats.size", &this->zfsArcSize, &len,
-	    NULL, 0) == 0 && this->zfsArcSize != 0) {
-		  this->zfsArcEnabled = 1;
-
-                  len = 5;
-                  sysctlnametomib("kstat.zfs.misc.arcstats.size", MIB_kstat_zfs_misc_arcstats_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.c_max", MIB_kstat_zfs_misc_arcstats_c_max, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.mfu_size", MIB_kstat_zfs_misc_arcstats_mfu_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.mru_size", MIB_kstat_zfs_misc_arcstats_mru_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.anon_size", MIB_kstat_zfs_misc_arcstats_anon_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.hdr_size", MIB_kstat_zfs_misc_arcstats_hdr_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.other_size", MIB_kstat_zfs_misc_arcstats_other_size, &len);
-   } else {
-		  this->zfsArcEnabled = 0;
-   }
+   this->zfs.enabled = openzfs_sysctl_init();
+   openzfs_sysctl_updateArcStats(&this->zfs);
 
    this->super.kernelThreads = 0;
    this->super.userlandThreads = 0;
@@ -252,7 +182,7 @@ void ProcessList_goThroughEntries(ProcessList* super) {
     dpl->prev_load = dpl->curr_load;
     ProcessList_allocateCPULoadInfo(&dpl->curr_load);
     ProcessList_getVMStats(&dpl->vm_stats);
-    DarwinProcessList_scanZfsArcstats(dpl);
+    openzfs_sysctl_updateArcStats(&dpl->zfs);
 
     /* Get the time difference */
     dpl->global_diff = 0;
diff --git a/darwin/DarwinProcessList.h b/darwin/DarwinProcessList.h
index 6686d05..73fbd34 100644
--- a/darwin/DarwinProcessList.h
+++ b/darwin/DarwinProcessList.h
@@ -21,6 +21,7 @@ negative value if more than the installed version
 int CompareKernelVersion(short int major, short int minor, short int component);
 
 #include "ProcessList.h"
+#include "zfs/ZfsArcStats.h"
 #include <mach/mach_host.h>
 #include <sys/sysctl.h>
 
@@ -35,15 +36,7 @@ typedef struct DarwinProcessList_ {
    uint64_t user_threads;
    uint64_t global_diff;
 
-   int zfsArcEnabled;
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcSize;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zfsArcAnon;
-   unsigned long long int zfsArcHeader;
-   unsigned long long int zfsArcOther;
-
+   ZfsArcStats zfs;
 } DarwinProcessList;
 
 
diff --git a/darwin/Platform.c b/darwin/Platform.c
index 52d60a9..8fbb9c9 100644
--- a/darwin/Platform.c
+++ b/darwin/Platform.c
@@ -246,18 +246,18 @@ void Platform_setSwapValues(Meter* mtr) {
 void Platform_setZfsArcValues(Meter* this) {
    DarwinProcessList* dpl = (DarwinProcessList*) this->pl;
 
-   this->total = dpl->zfsArcMax;
-   this->values[0] = dpl->zfsArcMFU;
-   this->values[1] = dpl->zfsArcMRU;
-   this->values[2] = dpl->zfsArcAnon;
-   this->values[3] = dpl->zfsArcHeader;
-   this->values[4] = dpl->zfsArcOther;
+   this->total = dpl->zfs.max;
+   this->values[0] = dpl->zfs.MFU;
+   this->values[1] = dpl->zfs.MRU;
+   this->values[2] = dpl->zfs.anon;
+   this->values[3] = dpl->zfs.header;
+   this->values[4] = dpl->zfs.other;
 
    // "Hide" the last value so it can
    // only be accessed by index and is not
    // displayed by the Bar or Graph style
    Meter_setItems(this, 5);
-   this->values[5] = dpl->zfsArcSize;
+   this->values[5] = dpl->zfs.size;
 }
 
 char* Platform_getProcessEnv(pid_t pid) {
diff --git a/darwin/Platform.h b/darwin/Platform.h
index 4acda2c..f836077 100644
--- a/darwin/Platform.h
+++ b/darwin/Platform.h
@@ -48,7 +48,7 @@ void Platform_setMemoryValues(Meter* mtr);
 
 void Platform_setSwapValues(Meter* mtr);
 
-void Platform_setZfsArcValues(Meter* mtr);
+void Platform_setZfsArcValues(Meter* this);
 
 char* Platform_getProcessEnv(pid_t pid);
 
diff --git a/freebsd/FreeBSDProcessList.c b/freebsd/FreeBSDProcessList.c
index 94cbaa1..1cbfdaa 100644
--- a/freebsd/FreeBSDProcessList.c
+++ b/freebsd/FreeBSDProcessList.c
@@ -8,6 +8,8 @@ in the source distribution for its full text.
 #include "ProcessList.h"
 #include "FreeBSDProcessList.h"
 #include "FreeBSDProcess.h"
+#include "zfs/ZfsArcStats.h"
+#include "zfs/openzfs_sysctl.h"
 
 #include <unistd.h>
 #include <stdlib.h>
@@ -21,6 +23,8 @@ in the source distribution for its full text.
 
 /*{
 
+#include "zfs/ZfsArcStats.h"
+
 #include <kvm.h>
 #include <sys/param.h>
 #include <sys/jail.h>
@@ -45,20 +49,12 @@ typedef struct FreeBSDProcessList_ {
    ProcessList super;
    kvm_t* kd;
 
-   int zfsArcEnabled;
-
    unsigned long long int memWire;
    unsigned long long int memActive;
    unsigned long long int memInactive;
    unsigned long long int memFree;
-   unsigned long long int memZfsArc;
 
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zFsArcAnon;
-   unsigned long long int zFsArcHeader;
-   unsigned long long int zFsArcOther;
+   ZfsArcStats zfs;
 
    CPUData* cpus;
 
@@ -86,14 +82,6 @@ static int MIB_vm_stats_vm_v_free_count[4];
 
 static int MIB_vfs_bufspace[2];
 
-static int MIB_kstat_zfs_misc_arcstats_size[5];
-static int MIB_vfs_zfs_arc_max[3];
-static int MIB_kstat_zfs_misc_arcstats_mfu_size[5];
-static int MIB_kstat_zfs_misc_arcstats_mru_size[5];
-static int MIB_kstat_zfs_misc_arcstats_anon_size[5];
-static int MIB_kstat_zfs_misc_arcstats_hdr_size[5];
-static int MIB_kstat_zfs_misc_arcstats_other_size[5];
-
 static int MIB_kern_cp_time[2];
 static int MIB_kern_cp_times[2];
 static int kernelFScale;
@@ -130,25 +118,8 @@ ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList, ui
 
    len = 2; sysctlnametomib("vfs.bufspace", MIB_vfs_bufspace, &len);
 
-   len = sizeof(fpl->memZfsArc);
-   if (sysctlbyname("kstat.zfs.misc.arcstats.size", &fpl->memZfsArc, &len,
-	    NULL, 0) == 0 && fpl->memZfsArc != 0) {
-                  len = 5; sysctlnametomib("kstat.zfs.misc.arcstats.size", MIB_kstat_zfs_misc_arcstats_size, &len);
-		  fpl->zfsArcEnabled = 1;
-
-                  len = 3;
-                  sysctlnametomib("vfs.zfs.arc_max", MIB_vfs_zfs_arc_max, &len);
-
-                  len = 5;
-                  sysctlnametomib("kstat.zfs.misc.arcstats.mfu_size", MIB_kstat_zfs_misc_arcstats_mfu_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.mru_size", MIB_kstat_zfs_misc_arcstats_mru_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.anon_size", MIB_kstat_zfs_misc_arcstats_anon_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.hdr_size", MIB_kstat_zfs_misc_arcstats_hdr_size, &len);
-                  sysctlnametomib("kstat.zfs.misc.arcstats.other_size", MIB_kstat_zfs_misc_arcstats_other_size, &len);
-   } else {
-		  fpl->zfsArcEnabled = 0;
-   }
-
+   fpl->zfs.enabled = openzfs_sysctl_init();
+   openzfs_sysctl_updateArcStats(&fpl->zfs);
 
    int smp = 0;
    len = sizeof(smp);
@@ -339,36 +310,9 @@ static inline void FreeBSDProcessList_scanMemoryInfo(ProcessList* pl) {
    sysctl(MIB_vm_stats_vm_v_cache_count, 4, &(pl->cachedMem), &len, NULL, 0);
    pl->cachedMem *= pageSizeKb;
 
-   if (fpl->zfsArcEnabled) {
-      len = sizeof(fpl->memZfsArc);
-      sysctl(MIB_kstat_zfs_misc_arcstats_size, 5, &(fpl->memZfsArc), &len , NULL, 0);
-      fpl->memZfsArc /= 1024;
-      fpl->memWire -= fpl->memZfsArc;
-      pl->cachedMem += fpl->memZfsArc;
-
-      len = sizeof(fpl->zfsArcMax);
-      sysctl(MIB_vfs_zfs_arc_max, 3, &(fpl->zfsArcMax), &len , NULL, 0);
-      fpl->zfsArcMax /= 1024;
-
-      len = sizeof(fpl->zfsArcMFU);
-      sysctl(MIB_kstat_zfs_misc_arcstats_mfu_size, 5, &(fpl->zfsArcMFU), &len , NULL, 0);
-      fpl->zfsArcMFU /= 1024;
-
-      len = sizeof(fpl->zfsArcMRU);
-      sysctl(MIB_kstat_zfs_misc_arcstats_mru_size, 5, &(fpl->zfsArcMRU), &len , NULL, 0);
-      fpl->zfsArcMRU /= 1024;
-
-      len = sizeof(fpl->zfsArcAnon);
-      sysctl(MIB_kstat_zfs_misc_arcstats_anon_size, 5, &(fpl->zfsArcAnon), &len , NULL, 0);
-      fpl->zfsArcAnon /= 1024;
-
-      len = sizeof(fpl->zfsArcHeader);
-      sysctl(MIB_kstat_zfs_misc_arcstats_hdr_size, 5, &(fpl->zfsArcHeader), &len , NULL, 0);
-      fpl->zfsArcHeader /= 1024;
-
-      len = sizeof(fpl->zfsArcOther);
-      sysctl(MIB_kstat_zfs_misc_arcstats_other_size, 5, &(fpl->zfsArcOther), &len , NULL, 0);
-      fpl->zfsArcOther /= 1024;
+   if (fpl->zfs.enabled) {
+      fpl->memWire -= fpl->zfs.size;
+      pl->cachedMem += fpl->zfs.size;
    }
 
    pl->usedMem = fpl->memActive + fpl->memWire;
@@ -466,6 +410,7 @@ void ProcessList_goThroughEntries(ProcessList* this) {
    bool hideKernelThreads = settings->hideKernelThreads;
    bool hideUserlandThreads = settings->hideUserlandThreads;
 
+   openzfs_sysctl_updateArcStats(&fpl->zfs);
    FreeBSDProcessList_scanMemoryInfo(this);
    FreeBSDProcessList_scanCPUTime(this);
 
diff --git a/freebsd/FreeBSDProcessList.h b/freebsd/FreeBSDProcessList.h
index cf96a70..7c1b7ad 100644
--- a/freebsd/FreeBSDProcessList.h
+++ b/freebsd/FreeBSDProcessList.h
@@ -10,6 +10,8 @@ in the source distribution for its full text.
 */
 
 
+#include "zfs/ZfsArcStats.h"
+
 #include <kvm.h>
 #include <sys/param.h>
 #include <sys/jail.h>
@@ -34,20 +36,12 @@ typedef struct FreeBSDProcessList_ {
    ProcessList super;
    kvm_t* kd;
 
-   int zfsArcEnabled;
-
    unsigned long long int memWire;
    unsigned long long int memActive;
    unsigned long long int memInactive;
    unsigned long long int memFree;
-   unsigned long long int memZfsArc;
-
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zfsArcAnon;
-   unsigned long long int zfsArcHeader;
-   unsigned long long int zfsArcOther;
+
+   ZfsArcStats zfs;
 
    CPUData* cpus;
 
diff --git a/freebsd/Platform.c b/freebsd/Platform.c
index d8d2ed0..05c0e92 100644
--- a/freebsd/Platform.c
+++ b/freebsd/Platform.c
@@ -202,18 +202,18 @@ void Platform_setSwapValues(Meter* this) {
 void Platform_setZfsArcValues(Meter* this) {
    FreeBSDProcessList* fpl = (FreeBSDProcessList*) this->pl;
 
-   this->total = fpl->zfsArcMax;
-   this->values[0] = fpl->zfsArcMFU;
-   this->values[1] = fpl->zfsArcMRU;
-   this->values[2] = fpl->zfsArcAnon;
-   this->values[3] = fpl->zfsArcHeader;
-   this->values[4] = fpl->zfsArcOther;
+   this->total = fpl->zfs.max;
+   this->values[0] = fpl->zfs.MFU;
+   this->values[1] = fpl->zfs.MRU;
+   this->values[2] = fpl->zfs.anon;
+   this->values[3] = fpl->zfs.header;
+   this->values[4] = fpl->zfs.other;
 
    // "Hide" the last value so it can
    // only be accessed by index and is not
    // displayed by the Bar or Graph style
    Meter_setItems(this, 5);
-   this->values[5] = fpl->memZfsArc;
+   this->values[5] = fpl->zfs.size;
 }
 
 void Platform_setTasksValues(Meter* this) {
diff --git a/linux/LinuxProcessList.c b/linux/LinuxProcessList.c
index 4d19185..3e88910 100644
--- a/linux/LinuxProcessList.c
+++ b/linux/LinuxProcessList.c
@@ -46,6 +46,7 @@ in the source distribution for its full text.
 /*{
 
 #include "ProcessList.h"
+#include "zfs/ZfsArcStats.h"
 
 extern long long btime;
 
@@ -95,14 +96,7 @@ typedef struct LinuxProcessList_ {
    int netlink_family;
    #endif
 
-   int zfsArcEnabled;
-   unsigned long long int memZfsArc;
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zfsArcAnon;
-   unsigned long long int zfsArcHeader;
-   unsigned long long int zfsArcOther;
+   ZfsArcStats zfs;
 } LinuxProcessList;
 
 #ifndef PROCDIR
@@ -984,7 +978,7 @@ static inline void LinuxProcessList_scanZfsArcstats(LinuxProcessList* lpl) {
 
    FILE* file = fopen(PROCARCSTATSFILE, "r");
    if (file == NULL) {
-      lpl->zfsArcEnabled = 0;
+      lpl->zfs.enabled = 0;
       return;
    }
    char buffer[128];
@@ -992,13 +986,13 @@ static inline void LinuxProcessList_scanZfsArcstats(LinuxProcessList* lpl) {
       #define tryRead(label, variable) do { if (String_startsWith(buffer, label) && sscanf(buffer + strlen(label), " %*2u %32llu", variable)) { break; } } while(0)
       switch (buffer[0]) {
       case 'c':
-         tryRead("c_max", &lpl->zfsArcMax);
+         tryRead("c_max", &lpl->zfs.max);
          break;
       case 's':
-         tryRead("size", &lpl->memZfsArc);
+         tryRead("size", &lpl->zfs.size);
          break;
       case 'h':
-         tryRead("hdr_size", &lpl->zfsArcHeader);
+         tryRead("hdr_size", &lpl->zfs.header);
          break;
       case 'd':
          tryRead("dbuf_size", &dbufSize);
@@ -1008,25 +1002,25 @@ static inline void LinuxProcessList_scanZfsArcstats(LinuxProcessList* lpl) {
          tryRead("bonus_size", &bonusSize);
          break;
       case 'a':
-         tryRead("anon_size", &lpl->zfsArcAnon);
+         tryRead("anon_size", &lpl->zfs.anon);
          break;
       case 'm':
-         tryRead("mfu_size", &lpl->zfsArcMFU);
-         tryRead("mru_size", &lpl->zfsArcMRU);
+         tryRead("mfu_size", &lpl->zfs.MFU);
+         tryRead("mru_size", &lpl->zfs.MRU);
          break;
       }
       #undef tryRead
    }
    fclose(file);
 
-   lpl->zfsArcEnabled = (lpl->memZfsArc > 0 ? 1 : 0);
-   lpl->memZfsArc    /= 1024;
-   lpl->zfsArcMax    /= 1024;
-   lpl->zfsArcMFU    /= 1024;
-   lpl->zfsArcMRU    /= 1024;
-   lpl->zfsArcAnon   /= 1024;
-   lpl->zfsArcHeader /= 1024;
-   lpl->zfsArcOther   = (dbufSize + dnodeSize + bonusSize) / 1024;
+   lpl->zfs.enabled = (lpl->zfs.size > 0 ? 1 : 0);
+   lpl->zfs.size    /= 1024;
+   lpl->zfs.max    /= 1024;
+   lpl->zfs.MFU    /= 1024;
+   lpl->zfs.MRU    /= 1024;
+   lpl->zfs.anon   /= 1024;
+   lpl->zfs.header /= 1024;
+   lpl->zfs.other   = (dbufSize + dnodeSize + bonusSize) / 1024;
 }
 
 static inline double LinuxProcessList_scanCPUTime(LinuxProcessList* this) {
diff --git a/linux/LinuxProcessList.h b/linux/LinuxProcessList.h
index 749231e..353fe60 100644
--- a/linux/LinuxProcessList.h
+++ b/linux/LinuxProcessList.h
@@ -19,6 +19,7 @@ in the source distribution for its full text.
 
 
 #include "ProcessList.h"
+#include "zfs/ZfsArcStats.h"
 
 extern long long btime;
 
@@ -68,14 +69,7 @@ typedef struct LinuxProcessList_ {
    int netlink_family;
    #endif
 
-   int zfsArcEnabled;
-   unsigned long long int memZfsArc;
-   unsigned long long int zfsArcMax;
-   unsigned long long int zfsArcMFU;
-   unsigned long long int zfsArcMRU;
-   unsigned long long int zfsArcAnon;
-   unsigned long long int zfsArcHeader;
-   unsigned long long int zfsArcOther;
+   ZfsArcStats zfs;
 } LinuxProcessList;
 
 #ifndef PROCDIR
diff --git a/linux/Platform.c b/linux/Platform.c
index 4e73c61..e2a3c6d 100644
--- a/linux/Platform.c
+++ b/linux/Platform.c
@@ -218,18 +218,18 @@ void Platform_setSwapValues(Meter* this) {
 void Platform_setZfsArcValues(Meter* this) {
    LinuxProcessList* lpl = (LinuxProcessList*) this->pl;
 
-   this->total = lpl->zfsArcMax;
-   this->values[0] = lpl->zfsArcMFU;
-   this->values[1] = lpl->zfsArcMRU;
-   this->values[2] = lpl->zfsArcAnon;
-   this->values[3] = lpl->zfsArcHeader;
-   this->values[4] = lpl->zfsArcOther;
+   this->total = lpl->zfs.max;
+   this->values[0] = lpl->zfs.MFU;
+   this->values[1] = lpl->zfs.MRU;
+   this->values[2] = lpl->zfs.anon;
+   this->values[3] = lpl->zfs.header;
+   this->values[4] = lpl->zfs.other;
 
    // "Hide" the last value so it can
    // only be accessed by index and is not
    // displayed by the Bar or Graph style
    Meter_setItems(this, 5);
-   this->values[5] = lpl->memZfsArc;
+   this->values[5] = lpl->zfs.size;
 }
 
 char* Platform_getProcessEnv(pid_t pid) {
diff --git a/zfs/ZfsArcStats.c b/zfs/ZfsArcStats.c
new file mode 100644
index 0000000..c33076a
--- /dev/null
+++ b/zfs/ZfsArcStats.c
@@ -0,0 +1,19 @@
+/*
+htop - ZfsArcStats.c
+(C) 2014 Hisham H. Muhammad
+Released under the GNU GPL, see the COPYING file
+in the source distribution for its full text.
+*/
+
+/*{
+typedef struct ZfsArcStats_ {
+   int enabled;
+   unsigned long long int max;
+   unsigned long long int size;
+   unsigned long long int MFU;
+   unsigned long long int MRU;
+   unsigned long long int anon;
+   unsigned long long int header;
+   unsigned long long int other;
+} ZfsArcStats;
+}*/
diff --git a/zfs/ZfsArcStats.h b/zfs/ZfsArcStats.h
new file mode 100644
index 0000000..3697af2
--- /dev/null
+++ b/zfs/ZfsArcStats.h
@@ -0,0 +1,23 @@
+/* Do not edit this file. It was automatically generated. */
+
+#ifndef HEADER_ZfsArcStats
+#define HEADER_ZfsArcStats
+/*
+htop - ZfsArcStats.h
+(C) 2014 Hisham H. Muhammad
+Released under the GNU GPL, see the COPYING file
+in the source distribution for its full text.
+*/
+
+typedef struct ZfsArcStats_ {
+   int enabled;
+   unsigned long long int max;
+   unsigned long long int size;
+   unsigned long long int MFU;
+   unsigned long long int MRU;
+   unsigned long long int anon;
+   unsigned long long int header;
+   unsigned long long int other;
+} ZfsArcStats;
+
+#endif
diff --git a/zfs/openzfs_sysctl.c b/zfs/openzfs_sysctl.c
new file mode 100644
index 0000000..ce48f23
--- /dev/null
+++ b/zfs/openzfs_sysctl.c
@@ -0,0 +1,81 @@
+/*
+htop - zfs/openzfs_sysctl.c
+(C) 2014 Hisham H. Muhammad
+Released under the GNU GPL, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include "zfs/openzfs_sysctl.h"
+#include "zfs/ZfsArcStats.h"
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+static int MIB_kstat_zfs_misc_arcstats_size[5];
+static int MIB_kstat_zfs_misc_arcstats_c_max[5];
+static int MIB_kstat_zfs_misc_arcstats_mfu_size[5];
+static int MIB_kstat_zfs_misc_arcstats_mru_size[5];
+static int MIB_kstat_zfs_misc_arcstats_anon_size[5];
+static int MIB_kstat_zfs_misc_arcstats_hdr_size[5];
+static int MIB_kstat_zfs_misc_arcstats_other_size[5];
+
+/*{
+#include "zfs/ZfsArcStats.h"
+}*/
+
+int openzfs_sysctl_init() {
+   size_t len;
+   unsigned long long int arcSize;
+
+   len = sizeof(arcSize);
+   if (sysctlbyname("kstat.zfs.misc.arcstats.size", &arcSize, &len,
+	    NULL, 0) == 0 && arcSize != 0) {
+                  len = 5; sysctlnametomib("kstat.zfs.misc.arcstats.size", MIB_kstat_zfs_misc_arcstats_size, &len);
+
+                  sysctlnametomib("kstat.zfs.misc.arcstats.c_max", MIB_kstat_zfs_misc_arcstats_c_max, &len);
+                  sysctlnametomib("kstat.zfs.misc.arcstats.mfu_size", MIB_kstat_zfs_misc_arcstats_mfu_size, &len);
+                  sysctlnametomib("kstat.zfs.misc.arcstats.mru_size", MIB_kstat_zfs_misc_arcstats_mru_size, &len);
+                  sysctlnametomib("kstat.zfs.misc.arcstats.anon_size", MIB_kstat_zfs_misc_arcstats_anon_size, &len);
+                  sysctlnametomib("kstat.zfs.misc.arcstats.hdr_size", MIB_kstat_zfs_misc_arcstats_hdr_size, &len);
+                  sysctlnametomib("kstat.zfs.misc.arcstats.other_size", MIB_kstat_zfs_misc_arcstats_other_size, &len);
+                  return 1;
+   } else {
+		  return 0;
+   }
+}
+
+void openzfs_sysctl_updateArcStats(ZfsArcStats *stats) {
+   size_t len;
+
+   if (stats->enabled) {
+      len = sizeof(stats->size);
+      sysctl(MIB_kstat_zfs_misc_arcstats_size, 5, &(stats->size), &len , NULL, 0);
+      stats->size /= 1024;
+
+      len = sizeof(stats->max);
+      sysctl(MIB_kstat_zfs_misc_arcstats_c_max, 5, &(stats->max), &len , NULL, 0);
+      stats->max /= 1024;
+
+      len = sizeof(stats->MFU);
+      sysctl(MIB_kstat_zfs_misc_arcstats_mfu_size, 5, &(stats->MFU), &len , NULL, 0);
+      stats->MFU /= 1024;
+
+      len = sizeof(stats->MRU);
+      sysctl(MIB_kstat_zfs_misc_arcstats_mru_size, 5, &(stats->MRU), &len , NULL, 0);
+      stats->MRU /= 1024;
+
+      len = sizeof(stats->anon);
+      sysctl(MIB_kstat_zfs_misc_arcstats_anon_size, 5, &(stats->anon), &len , NULL, 0);
+      stats->anon /= 1024;
+
+      len = sizeof(stats->header);
+      sysctl(MIB_kstat_zfs_misc_arcstats_hdr_size, 5, &(stats->header), &len , NULL, 0);
+      stats->header /= 1024;
+
+      len = sizeof(stats->other);
+      sysctl(MIB_kstat_zfs_misc_arcstats_other_size, 5, &(stats->other), &len , NULL, 0);
+      stats->other /= 1024;
+   }
+}
diff --git a/zfs/openzfs_sysctl.h b/zfs/openzfs_sysctl.h
new file mode 100644
index 0000000..7c04bd7
--- /dev/null
+++ b/zfs/openzfs_sysctl.h
@@ -0,0 +1,18 @@
+/* Do not edit this file. It was automatically generated. */
+
+#ifndef HEADER_openzfs
+#define HEADER_openzfs
+/*
+htop - zfs/openzfs_sysctl.h
+(C) 2014 Hisham H. Muhammad
+Released under the GNU GPL, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include "zfs/ZfsArcStats.h"
+
+int openzfs_sysctl_init();
+
+void openzfs_sysctl_updateArcStats(ZfsArcStats *stats);
+
+#endif
-- 
2.20.1