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xnu-2050.48.11.tar.gz
[apple/xnu.git] / bsd / kern / kern_memorystatus.c
index f5e141455921d02845e6ec2b974a49d3dc47977f..1bf8dd616c128713e27601a50046bec5ba7e5916 100644 (file)
  *
  */
 
-#include <sys/kern_event.h>
-#include <sys/kern_memorystatus.h>
-
 #include <kern/sched_prim.h>
+#include <kern/kalloc.h>
+#include <kern/assert.h>
+#include <kern/debug.h>
 #include <kern/lock.h>
 #include <kern/task.h>
 #include <kern/thread.h>
+#include <kern/host.h>
 #include <libkern/libkern.h>
+#include <mach/mach_time.h>
 #include <mach/task.h>
 #include <mach/task_info.h>
+#include <mach/host_priv.h>
+#include <sys/kern_event.h>
 #include <sys/proc.h>
 #include <sys/signal.h>
 #include <sys/signalvar.h>
 #include <sys/sysctl.h>
+#include <sys/sysproto.h>
 #include <sys/wait.h>
+#include <sys/tree.h>
+#include <sys/priv.h>
+#include <pexpert/pexpert.h>
+
+#if CONFIG_FREEZE
+#include <vm/vm_protos.h>
+#include <vm/vm_map.h>
+#endif
+
+#include <sys/kern_memorystatus.h> 
+
+/* These are very verbose printfs(), enable with
+ * MEMORYSTATUS_DEBUG_LOG
+ */
+#if MEMORYSTATUS_DEBUG_LOG
+#define MEMORYSTATUS_DEBUG(cond, format, ...)      \
+do {                                              \
+       if (cond) { printf(format, ##__VA_ARGS__); } \
+} while(0)
+#else
+#define MEMORYSTATUS_DEBUG(cond, format, ...)
+#endif
+
+/* General memorystatus stuff */
+
+static void memorystatus_add_node(memorystatus_node *node);
+static void memorystatus_remove_node(memorystatus_node *node);
+static memorystatus_node *memorystatus_get_node(pid_t pid);
+static void memorystatus_release_node(memorystatus_node *node);
+
+int memorystatus_wakeup = 0;
+
+static void memorystatus_thread(void *param __unused, wait_result_t wr __unused);
+
+static memorystatus_node *next_memorystatus_node = NULL;
+
+static int memorystatus_list_count = 0;
+
+static lck_mtx_t * memorystatus_list_mlock;
+static lck_attr_t * memorystatus_lck_attr;
+static lck_grp_t * memorystatus_lck_grp;
+static lck_grp_attr_t * memorystatus_lck_grp_attr;
+
+static TAILQ_HEAD(memorystatus_list_head, memorystatus_node) memorystatus_list;
+
+static uint64_t memorystatus_idle_delay_time = 0;
+
+static unsigned int memorystatus_dirty_count = 0;
+
+extern void proc_dirty_start(struct proc *p);
+extern void proc_dirty_end(struct proc *p);
+
+/* Jetsam */
+
+#if CONFIG_JETSAM
+
+extern unsigned int    vm_page_free_count;
+extern unsigned int    vm_page_active_count;
+extern unsigned int    vm_page_inactive_count;
+extern unsigned int    vm_page_throttled_count;
+extern unsigned int    vm_page_purgeable_count;
+extern unsigned int    vm_page_wire_count;
+
+static lck_mtx_t * exit_list_mlock;
+
+static TAILQ_HEAD(exit_list_head, memorystatus_node) exit_list;
+
+static unsigned int memorystatus_kev_failure_count = 0;
+
+/* Counted in pages... */
+unsigned int memorystatus_delta = 0;
+
+unsigned int memorystatus_available_pages = (unsigned int)-1;
+unsigned int memorystatus_available_pages_critical = 0;
+unsigned int memorystatus_available_pages_highwater = 0;
+
+/* ...with the exception of the legacy level in percent. */
+unsigned int memorystatus_level = 0;
+
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_kev_failure_count, CTLFLAG_RD, &memorystatus_kev_failure_count, 0, "");
+SYSCTL_INT(_kern, OID_AUTO, memorystatus_level, CTLFLAG_RD, &memorystatus_level, 0, "");
+
+unsigned int memorystatus_jetsam_policy = kPolicyDefault;
+
+unsigned int memorystatus_jetsam_policy_offset_pages_more_free = 0;
+#if DEVELOPMENT || DEBUG
+unsigned int memorystatus_jetsam_policy_offset_pages_diagnostic = 0;
+#endif
+
+static memorystatus_jetsam_snapshot_t memorystatus_jetsam_snapshot;
+#define memorystatus_jetsam_snapshot_list memorystatus_jetsam_snapshot.entries
+
+static int memorystatus_jetsam_snapshot_list_count = 0;
+
+int memorystatus_jetsam_wakeup = 0;
+unsigned int memorystatus_jetsam_running = 1;
+
+static uint32_t memorystatus_task_page_count(task_t task);
+
+static void memorystatus_move_node_to_exit_list(memorystatus_node *node);
+
+static void memorystatus_update_levels_locked(void);
+
+static void memorystatus_jetsam_thread_block(void);
+static void memorystatus_jetsam_thread(void *param __unused, wait_result_t wr __unused);
+
+static int memorystatus_send_note(int event_code, void *data, size_t data_length);
+
+static uint32_t memorystatus_build_flags_from_state(uint32_t state);
+
+/* VM pressure */
+
+#if VM_PRESSURE_EVENTS
+
+typedef enum vm_pressure_level {
+        kVMPressureNormal   = 0,
+        kVMPressureWarning  = 1,
+        kVMPressureUrgent   = 2,
+        kVMPressureCritical = 3,
+} vm_pressure_level_t;
+
+static vm_pressure_level_t memorystatus_vm_pressure_level = kVMPressureNormal;
+
+unsigned int memorystatus_available_pages_pressure = 0;
+
+static inline boolean_t memorystatus_get_pressure_locked(void);
+static void memorystatus_check_pressure_reset(void);
+
+#endif /* VM_PRESSURE_EVENTS */
+
+#endif /* CONFIG_JETSAM */
+
+/* Freeze */
+
+#if CONFIG_FREEZE
+
+static unsigned int memorystatus_suspended_resident_count = 0;
+static unsigned int memorystatus_suspended_count = 0;
+
+boolean_t memorystatus_freeze_enabled = FALSE;
+int memorystatus_freeze_wakeup = 0;
+
+static inline boolean_t memorystatus_can_freeze_processes(void);
+static boolean_t memorystatus_can_freeze(boolean_t *memorystatus_freeze_swap_low);
+
+static void memorystatus_freeze_thread(void *param __unused, wait_result_t wr __unused);
+
+/* Thresholds */
+static unsigned int memorystatus_freeze_threshold = 0;
+
+static unsigned int memorystatus_freeze_pages_min = FREEZE_PAGES_MIN;
+static unsigned int memorystatus_freeze_pages_max = FREEZE_PAGES_MAX;
+
+static unsigned int memorystatus_frozen_count = 0;
+
+static unsigned int memorystatus_freeze_suspended_threshold = FREEZE_SUSPENDED_THRESHOLD_DEFAULT;
+
+/* Stats */
+static uint64_t memorystatus_freeze_count = 0;
+static uint64_t memorystatus_freeze_pageouts = 0;
+
+/* Throttling */
+static throttle_interval_t throttle_intervals[] = {
+       {      60,  8, 0, 0, { 0, 0 }, FALSE }, /* 1 hour intermediate interval, 8x burst */
+       { 24 * 60,  1, 0, 0, { 0, 0 }, FALSE }, /* 24 hour long interval, no burst */
+};
+
+static uint64_t memorystatus_freeze_throttle_count = 0;
+
+#endif /* CONFIG_FREEZE */
+
+#if CONFIG_JETSAM
+
+/* Debug */
+
+#if DEVELOPMENT || DEBUG
+
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_available_pages, CTLFLAG_RD, &memorystatus_available_pages, 0, "");
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_available_pages_critical, CTLFLAG_RW, &memorystatus_available_pages_critical, 0, "");
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_available_pages_highwater, CTLFLAG_RW, &memorystatus_available_pages_highwater, 0, "");
+#if VM_PRESSURE_EVENTS
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_available_pages_pressure, CTLFLAG_RW, &memorystatus_available_pages_pressure, 0, "");
+#endif /* VM_PRESSURE_EVENTS */
+
+/* Diagnostic code */
+enum {
+       kJetsamDiagnosticModeNone =              0, 
+       kJetsamDiagnosticModeAll  =              1,
+       kJetsamDiagnosticModeStopAtFirstActive = 2,
+       kJetsamDiagnosticModeCount
+} jetsam_diagnostic_mode = kJetsamDiagnosticModeNone;
+
+static int jetsam_diagnostic_suspended_one_active_proc = 0;
+
+static int
+sysctl_jetsam_diagnostic_mode SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+
+       const char *diagnosticStrings[] = {
+               "jetsam: diagnostic mode: resetting critical level.",
+               "jetsam: diagnostic mode: will examine all processes",
+               "jetsam: diagnostic mode: will stop at first active process"                
+       };
+        
+       int error, val = jetsam_diagnostic_mode;
+       boolean_t changed = FALSE;
+
+       error = sysctl_handle_int(oidp, &val, 0, req);
+       if (error || !req->newptr)
+               return (error);
+       if ((val < 0) || (val >= kJetsamDiagnosticModeCount)) {
+               printf("jetsam: diagnostic mode: invalid value - %d\n", val);
+               return EINVAL;
+       }
+       
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if ((unsigned int) val != jetsam_diagnostic_mode) {
+               jetsam_diagnostic_mode = val;
+
+               memorystatus_jetsam_policy &= ~kPolicyDiagnoseActive;
+                
+               switch (jetsam_diagnostic_mode) {
+               case kJetsamDiagnosticModeNone:
+                       /* Already cleared */
+                       break;
+               case kJetsamDiagnosticModeAll:
+                       memorystatus_jetsam_policy |= kPolicyDiagnoseAll;
+                       break;
+               case kJetsamDiagnosticModeStopAtFirstActive:
+                       memorystatus_jetsam_policy |= kPolicyDiagnoseFirst;
+                       break;
+               default:
+                       /* Already validated */
+                       break;
+               }
+               
+               memorystatus_update_levels_locked();
+               changed = TRUE;
+       }
+        
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       if (changed) {
+               printf("%s\n", diagnosticStrings[val]);
+       }
+       
+       return (0);
+}
+
+SYSCTL_PROC(_debug, OID_AUTO, jetsam_diagnostic_mode, CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_ANYBODY,
+               &jetsam_diagnostic_mode, 0, sysctl_jetsam_diagnostic_mode, "I", "Jetsam Diagnostic Mode");
+
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_jetsam_policy_offset_pages_more_free, CTLFLAG_RW, &memorystatus_jetsam_policy_offset_pages_more_free, 0, "");
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_jetsam_policy_offset_pages_diagnostic, CTLFLAG_RW, &memorystatus_jetsam_policy_offset_pages_diagnostic, 0, "");
+
+#if VM_PRESSURE_EVENTS
+
+#include "vm_pressure.h"
+
+static int
+sysctl_memorystatus_vm_pressure_level SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2, oidp)
+       int error = 0;
+
+       error = priv_check_cred(kauth_cred_get(), PRIV_VM_PRESSURE, 0);
+       if (error)
+               return (error);
+
+       return SYSCTL_OUT(req, &memorystatus_vm_pressure_level, sizeof(memorystatus_vm_pressure_level));
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_vm_pressure_level, CTLTYPE_INT|CTLFLAG_RD|CTLFLAG_LOCKED|CTLFLAG_MASKED,
+    0, 0, &sysctl_memorystatus_vm_pressure_level, "I", "");
+
+static int
+sysctl_memorystatus_vm_pressure_send SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+
+       int error, pid = 0;
+
+       error = sysctl_handle_int(oidp, &pid, 0, req);
+       if (error || !req->newptr)
+               return (error);
+
+       if (vm_dispatch_pressure_note_to_pid(pid)) {
+               return 0;
+       }
+
+       return EINVAL;
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_vm_pressure_send, CTLTYPE_INT|CTLFLAG_WR|CTLFLAG_LOCKED|CTLFLAG_MASKED,
+    0, 0, &sysctl_memorystatus_vm_pressure_send, "I", "");
+
+#endif /* VM_PRESSURE_EVENTS */
+
+#endif /* CONFIG_JETSAM */
+
+#if CONFIG_FREEZE
+
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_freeze_threshold, CTLFLAG_RW, &memorystatus_freeze_threshold, 0, "");
+
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_freeze_pages_min, CTLFLAG_RW, &memorystatus_freeze_pages_min, 0, "");
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_freeze_pages_max, CTLFLAG_RW, &memorystatus_freeze_pages_max, 0, "");
+
+SYSCTL_QUAD(_kern, OID_AUTO, memorystatus_freeze_count, CTLFLAG_RD, &memorystatus_freeze_count, "");
+SYSCTL_QUAD(_kern, OID_AUTO, memorystatus_freeze_pageouts, CTLFLAG_RD, &memorystatus_freeze_pageouts, "");
+SYSCTL_QUAD(_kern, OID_AUTO, memorystatus_freeze_throttle_count, CTLFLAG_RD, &memorystatus_freeze_throttle_count, "");
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_freeze_min_processes, CTLFLAG_RW, &memorystatus_freeze_suspended_threshold, 0, "");
+
+boolean_t memorystatus_freeze_throttle_enabled = TRUE;
+SYSCTL_UINT(_kern, OID_AUTO, memorystatus_freeze_throttle_enabled, CTLFLAG_RW, &memorystatus_freeze_throttle_enabled, 0, "");
+
+/* 
+ * Manual trigger of freeze and thaw for dev / debug kernels only.
+ */
+static int
+sysctl_memorystatus_freeze SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+
+       int error, pid = 0;
+       proc_t p;
+
+       error = sysctl_handle_int(oidp, &pid, 0, req);
+       if (error || !req->newptr)
+               return (error);
+
+       p = proc_find(pid);
+       if (p != NULL) {
+               uint32_t purgeable, wired, clean, dirty;
+               boolean_t shared;
+               uint32_t max_pages = MIN(default_pager_swap_pages_free(), memorystatus_freeze_pages_max);
+               task_freeze(p->task, &purgeable, &wired, &clean, &dirty, max_pages, &shared, FALSE);
+               proc_rele(p);
+        return 0;
+       }
+
+       return EINVAL;
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_freeze, CTLTYPE_INT|CTLFLAG_WR|CTLFLAG_LOCKED|CTLFLAG_MASKED,
+    0, 0, &sysctl_memorystatus_freeze, "I", "");
+
+static int
+sysctl_memorystatus_available_pages_thaw SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2)
+
+       int error, pid = 0;
+       proc_t p;
+
+       error = sysctl_handle_int(oidp, &pid, 0, req);
+       if (error || !req->newptr)
+               return (error);
+
+       p = proc_find(pid);
+       if (p != NULL) {
+               task_thaw(p->task);
+               proc_rele(p);
+               return 0;
+       }
+
+       return EINVAL;
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_thaw, CTLTYPE_INT|CTLFLAG_WR|CTLFLAG_LOCKED|CTLFLAG_MASKED,
+    0, 0, &sysctl_memorystatus_available_pages_thaw, "I", "");
+
+#endif /* CONFIG_FREEZE */
+
+#endif /* DEVELOPMENT || DEBUG */
+
+__private_extern__ void
+memorystatus_init(void)
+{
+       thread_t thread = THREAD_NULL;
+       kern_return_t result;
+       
+       memorystatus_lck_attr = lck_attr_alloc_init();
+       memorystatus_lck_grp_attr = lck_grp_attr_alloc_init();
+       memorystatus_lck_grp = lck_grp_alloc_init("memorystatus",  memorystatus_lck_grp_attr);
+       memorystatus_list_mlock = lck_mtx_alloc_init(memorystatus_lck_grp, memorystatus_lck_attr);
+       TAILQ_INIT(&memorystatus_list);
+
+#if CONFIG_JETSAM
+       exit_list_mlock = lck_mtx_alloc_init(memorystatus_lck_grp, memorystatus_lck_attr);
+       TAILQ_INIT(&exit_list);
+       
+       memorystatus_delta = DELTA_PERCENT * atop_64(max_mem) / 100;
+#endif
+
+#if CONFIG_FREEZE
+       memorystatus_freeze_threshold = (FREEZE_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+#endif
+
+       nanoseconds_to_absolutetime((uint64_t)IDLE_EXIT_TIME_SECS * NSEC_PER_SEC, &memorystatus_idle_delay_time);
+
+       result = kernel_thread_start(memorystatus_thread, NULL, &thread);
+       if (result == KERN_SUCCESS) {
+               thread_deallocate(thread);
+       } else {
+               panic("Could not create memorystatus_thread");
+       }
+
+#if CONFIG_JETSAM
+       memorystatus_jetsam_policy_offset_pages_more_free = (POLICY_MORE_FREE_OFFSET_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+#if DEVELOPMENT || DEBUG
+       memorystatus_jetsam_policy_offset_pages_diagnostic = (POLICY_DIAGNOSTIC_OFFSET_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+#endif
+
+       /* No contention at this point */
+       memorystatus_update_levels_locked();
+       
+       result = kernel_thread_start(memorystatus_jetsam_thread, NULL, &thread);
+       if (result == KERN_SUCCESS) {
+               thread_deallocate(thread);
+       } else {
+               panic("Could not create memorystatus_jetsam_thread");
+       }
+#endif
+}
+
+/*
+ * Node manipulation
+ */
+
+static void
+memorystatus_add_node(memorystatus_node *new_node)
+{
+       memorystatus_node *node;
+
+       /* Make sure we're called with the list lock held */
+       lck_mtx_assert(memorystatus_list_mlock, LCK_MTX_ASSERT_OWNED);
+
+       TAILQ_FOREACH(node, &memorystatus_list, link) {
+               if (node->priority <= new_node->priority) {
+                       break;
+               }
+       }
+
+       if (node) {
+               TAILQ_INSERT_BEFORE(node, new_node, link);
+       } else {
+               TAILQ_INSERT_TAIL(&memorystatus_list, new_node, link);
+       }
+
+       next_memorystatus_node = TAILQ_FIRST(&memorystatus_list);
+
+       memorystatus_list_count++;
+}
+
+static void
+memorystatus_remove_node(memorystatus_node *node) 
+{
+       /* Make sure we're called with the list lock held */
+       lck_mtx_assert(memorystatus_list_mlock, LCK_MTX_ASSERT_OWNED);
+
+       TAILQ_REMOVE(&memorystatus_list, node, link);
+       next_memorystatus_node = TAILQ_FIRST(&memorystatus_list);
+
+#if CONFIG_FREEZE    
+       if (node->state & (kProcessFrozen)) {
+               memorystatus_frozen_count--;
+       }
+
+       if (node->state & kProcessSuspended) {
+               memorystatus_suspended_resident_count -= node->resident_pages;
+               memorystatus_suspended_count--;
+       }
+#endif
+
+       memorystatus_list_count--;
+}
+
+/* Returns with the lock taken if found */
+static memorystatus_node *
+memorystatus_get_node(pid_t pid) 
+{
+       memorystatus_node *node;
+
+       lck_mtx_lock(memorystatus_list_mlock);
+
+       TAILQ_FOREACH(node, &memorystatus_list, link) {
+               if (node->pid == pid) {
+                       break;
+               }
+       }
+
+       if (!node) {
+               lck_mtx_unlock(memorystatus_list_mlock);                
+       }
+
+       return node;
+}
+
+static void
+memorystatus_release_node(memorystatus_node *node) 
+{
+#pragma unused(node)
+       lck_mtx_unlock(memorystatus_list_mlock);        
+}
+
+/* 
+ * List manipulation
+ */
+kern_return_t 
+memorystatus_list_add(pid_t pid, int priority, int high_water_mark)
+{
+
+#if !CONFIG_JETSAM
+#pragma unused(high_water_mark)
+#endif
+
+       memorystatus_node *new_node;
+
+       new_node = (memorystatus_node*)kalloc(sizeof(memorystatus_node));
+       if (!new_node) {
+               assert(FALSE);
+       }
+       memset(new_node, 0, sizeof(memorystatus_node));
+    
+       MEMORYSTATUS_DEBUG(1, "memorystatus_list_add: adding process %d with priority %d, high water mark %d.\n", pid, priority, high_water_mark);
+    
+       new_node->pid = pid;
+       new_node->priority = priority;
+#if CONFIG_JETSAM
+       new_node->hiwat_pages = high_water_mark;
+#endif    
+
+       lck_mtx_lock(memorystatus_list_mlock);
+    
+       memorystatus_add_node(new_node);
+        
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       return KERN_SUCCESS;
+}
+
+kern_return_t
+memorystatus_list_change(boolean_t effective, pid_t pid, int priority, int state_flags, int high_water_mark)
+{
+
+#if !CONFIG_JETSAM
+#pragma unused(high_water_mark)
+#endif
+       
+       kern_return_t ret;
+       memorystatus_node *node, *search;
+
+       MEMORYSTATUS_DEBUG(1, "memorystatus_list_change: changing process %d to priority %d with flags %d\n", pid, priority, state_flags);
+
+       lck_mtx_lock(memorystatus_list_mlock);
+
+       TAILQ_FOREACH(node, &memorystatus_list, link) {
+               if (node->pid == pid) {
+                       break;
+               }
+       }
+    
+       if (!node) {
+               ret = KERN_FAILURE;
+               goto out;             
+       }
+
+       if (effective && (node->state & kProcessPriorityUpdated)) {
+               MEMORYSTATUS_DEBUG(1, "memorystatus_list_change: effective change specified for pid %d, but change already occurred.\n", pid);
+               ret = KERN_FAILURE;
+               goto out;             
+       }
+
+       node->state |= kProcessPriorityUpdated;
+       if (state_flags != -1) {
+               node->state &= ~(kProcessActive|kProcessForeground);
+               if (state_flags & kMemorystatusFlagsFrontmost) {
+                       node->state |= kProcessForeground;
+               }
+               if (state_flags & kMemorystatusFlagsActive) {
+                       node->state |= kProcessActive;
+               }
+       }
+
+#if CONFIG_JETSAM        
+       if (high_water_mark != -1) {
+               node->hiwat_pages = high_water_mark;
+       }
+#endif
+
+       if (node->priority == priority) {
+               /* Priority unchanged */
+               MEMORYSTATUS_DEBUG(1, "memorystatus_list_change: same priority set for pid %d\n", pid);
+               ret = KERN_SUCCESS;
+               goto out;
+       }
+
+       if (node->priority < priority) {
+               /* Higher priority value (ie less important) - search backwards */
+               search = TAILQ_PREV(node, memorystatus_list_head, link);
+               TAILQ_REMOVE(&memorystatus_list, node, link);
+
+               node->priority = priority;
+               while (search && (search->priority <= node->priority)) {
+                       search = TAILQ_PREV(search, memorystatus_list_head, link);
+               }
+               if (search) {
+                       TAILQ_INSERT_AFTER(&memorystatus_list, search, node, link);
+               } else {
+                       TAILQ_INSERT_HEAD(&memorystatus_list, node, link);
+               }
+       } else {
+               /* Lower priority value (ie more important) - search forwards */
+               search = TAILQ_NEXT(node, link);
+               TAILQ_REMOVE(&memorystatus_list, node, link);
+
+               node->priority = priority;
+               while (search && (search->priority >= node->priority)) {
+                       search = TAILQ_NEXT(search, link);
+               }
+               if (search) {
+                       TAILQ_INSERT_BEFORE(search, node, link);
+               } else {
+                       TAILQ_INSERT_TAIL(&memorystatus_list, node, link);
+               }
+       }
+
+       next_memorystatus_node = TAILQ_FIRST(&memorystatus_list);
+       ret = KERN_SUCCESS;
+
+out:
+       lck_mtx_unlock(memorystatus_list_mlock);
+       return ret;
+}
+
+kern_return_t memorystatus_list_remove(pid_t pid)
+{
+       kern_return_t ret;
+       memorystatus_node *node = NULL;
+
+       MEMORYSTATUS_DEBUG(1, "memorystatus_list_remove: removing process %d\n", pid);
+
+#if CONFIG_JETSAM
+       /* Did we mark this as a exited process? */
+       lck_mtx_lock(exit_list_mlock);
+
+       TAILQ_FOREACH(node, &exit_list, link) {
+               if (node->pid == pid) {
+                       /* We did, so remove it from the list. The stats were updated when the queues were shifted. */
+                       TAILQ_REMOVE(&exit_list, node, link);
+                       break;
+               }
+       }
+
+       lck_mtx_unlock(exit_list_mlock);
+#endif
+
+       /* If not, search the main list */
+       if (!node) {
+               lck_mtx_lock(memorystatus_list_mlock);
+
+               TAILQ_FOREACH(node, &memorystatus_list, link) {
+                       if (node->pid == pid) {
+                               /* Remove from the list, and update accounting accordingly */
+                               memorystatus_remove_node(node);
+                               break;
+                       }
+               }
+
+               lck_mtx_unlock(memorystatus_list_mlock);
+       }
+
+       if (node) {
+               kfree(node, sizeof(memorystatus_node));
+               ret = KERN_SUCCESS; 
+       } else {
+               ret = KERN_FAILURE;
+       }
+
+       return ret;
+}
+
+kern_return_t 
+memorystatus_on_track_dirty(int pid, boolean_t track)
+{
+       kern_return_t ret = KERN_FAILURE;
+       memorystatus_node *node;
+       
+       node = memorystatus_get_node((pid_t)pid);
+       if (!node) {
+               return KERN_FAILURE;
+       }
+       
+       if (track & !(node->state & kProcessSupportsIdleExit)) {
+               node->state |= kProcessSupportsIdleExit;
+               node->clean_time = mach_absolute_time() + memorystatus_idle_delay_time;
+               ret = KERN_SUCCESS;
+       } else  if (!track & (node->state & kProcessSupportsIdleExit)) {
+               node->state &= ~kProcessSupportsIdleExit;
+               node->clean_time = 0;
+               ret = KERN_SUCCESS;             
+       }
+       
+       memorystatus_release_node(node);
+               
+       return ret;     
+}
+
+kern_return_t 
+memorystatus_on_dirty(int pid, boolean_t dirty)
+{
+       kern_return_t ret = KERN_FAILURE;
+       memorystatus_node *node;
+       
+       node = memorystatus_get_node((pid_t)pid);
+       if (!node) {
+               return KERN_FAILURE;
+       }
+       
+       if (dirty) {
+               if (!(node->state & kProcessDirty)) {
+                       node->state |= kProcessDirty;
+                       node->clean_time = 0;
+                       memorystatus_dirty_count++;
+                       ret = KERN_SUCCESS;
+               }
+       } else {
+               if (node->state & kProcessDirty) {
+                       node->state &= ~kProcessDirty;
+                       node->clean_time = mach_absolute_time() + memorystatus_idle_delay_time;
+                       memorystatus_dirty_count--;
+                       ret = KERN_SUCCESS;
+               }
+       }
+       
+       memorystatus_release_node(node);
+       
+       return ret;
+}
+
+void 
+memorystatus_on_suspend(int pid)
+{      
+       memorystatus_node *node = memorystatus_get_node((pid_t)pid);
+
+       if (node) {
+#if CONFIG_FREEZE
+               proc_t p;
+
+               p = proc_find(pid);
+               if (p != NULL) {
+                       uint32_t pages = memorystatus_task_page_count(p->task);
+                       proc_rele(p);
+                       node->resident_pages = pages;
+                       memorystatus_suspended_resident_count += pages;
+               }
+               memorystatus_suspended_count++;
+#endif
 
-extern unsigned int    vm_page_free_count;
-extern unsigned int    vm_page_active_count;
-extern unsigned int    vm_page_inactive_count;
-extern unsigned int    vm_page_purgeable_count;
-extern unsigned int    vm_page_wire_count;
+               node->state |= kProcessSuspended;
 
-static void kern_memorystatus_thread(void);
+               memorystatus_release_node(node);
+       }
+}
 
-int kern_memorystatus_wakeup = 0;
-int kern_memorystatus_level = 0;
-int kern_memorystatus_last_level = 0;
-unsigned int kern_memorystatus_kev_failure_count = 0;
-int kern_memorystatus_level_critical = 5;
+void
+memorystatus_on_resume(int pid)
+{      
+       memorystatus_node *node = memorystatus_get_node((pid_t)pid);
 
-static struct {
-       jetsam_kernel_stats_t stats;
-       size_t entry_count;
-       jetsam_snapshot_entry_t entries[kMaxSnapshotEntries];
-} jetsam_snapshot;
+       if (node) {
+#if CONFIG_FREEZE
+               boolean_t frozen = (node->state & kProcessFrozen);
+               if (node->state & (kProcessFrozen)) {
+                       memorystatus_frozen_count--;
+               }
+               memorystatus_suspended_resident_count -= node->resident_pages;
+               memorystatus_suspended_count--;
+#endif
 
-static jetsam_priority_entry_t jetsam_priority_list[kMaxPriorityEntries];
-#define jetsam_snapshot_list jetsam_snapshot.entries
+               node->state &= ~(kProcessSuspended | kProcessFrozen | kProcessIgnored);
 
-static int jetsam_priority_list_index = 0;
-static int jetsam_priority_list_count = 0;
-static int jetsam_snapshot_list_count = 0;
+               memorystatus_release_node(node);
 
-static lck_mtx_t * jetsam_list_mlock;
-static lck_attr_t * jetsam_lck_attr;
-static lck_grp_t * jetsam_lck_grp;
-static lck_grp_attr_t * jetsam_lck_grp_attr;
+#if CONFIG_FREEZE
+               if (frozen) {
+                       memorystatus_freeze_entry_t data = { pid, kMemorystatusFlagsThawed, 0 };
+                       memorystatus_send_note(kMemorystatusFreezeNote, &data, sizeof(data));
+               }
+#endif
+       }
+}
 
-SYSCTL_INT(_kern, OID_AUTO, memorystatus_level, CTLFLAG_RD, &kern_memorystatus_level, 0, "");
-SYSCTL_UINT(_kern, OID_AUTO, memorystatus_kev_failure_count, CTLFLAG_RD, &kern_memorystatus_kev_failure_count, 0, "");
+void
+memorystatus_on_inactivity(int pid)
+{
+#pragma unused(pid)
+#if CONFIG_FREEZE
+       /* Wake the freeze thread */
+       thread_wakeup((event_t)&memorystatus_freeze_wakeup);
+#endif 
+}
 
-__private_extern__ void
-kern_memorystatus_init(void)
+static void
+memorystatus_thread(void *param __unused, wait_result_t wr __unused)
 {
-    jetsam_lck_attr = lck_attr_alloc_init();
-    jetsam_lck_grp_attr= lck_grp_attr_alloc_init();
-    jetsam_lck_grp = lck_grp_alloc_init("jetsam",  jetsam_lck_grp_attr);
-    jetsam_list_mlock = lck_mtx_alloc_init(jetsam_lck_grp, jetsam_lck_attr);
+       static boolean_t initialized = FALSE;
+       memorystatus_node *node;
+       uint64_t current_time;
+       pid_t victim_pid = -1;
+
+       if (initialized == FALSE) {
+               initialized = TRUE;
+               assert_wait(&memorystatus_wakeup, THREAD_UNINT);
+               (void)thread_block((thread_continue_t)memorystatus_thread);
+       }
+
+       /*  Pick next idle exit victim. For now, just iterate through; ideally, this would be be more intelligent. */
+       current_time = mach_absolute_time();
+       
+       /* Set a cutoff so that we don't idle exit processes that went recently clean */
+       
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if (memorystatus_dirty_count) {
+               TAILQ_FOREACH(node, &memorystatus_list, link) {
+                       if ((node->state & kProcessSupportsIdleExit) && !(node->state & (kProcessDirty|kProcessIgnoreIdleExit))) {                              
+                               if (current_time >= node->clean_time) {
+                                       victim_pid = node->pid;
+                                       break;
+                               }
+                       }
+               }
+       }
+
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       if (-1 != victim_pid) {         
+               proc_t p = proc_find(victim_pid);
+               if (p != NULL) {
+                       boolean_t kill = FALSE;
+                       proc_dirty_start(p);
+                       /* Ensure process is still marked for idle exit and is clean */
+                       if ((p->p_dirty & (P_DIRTY_ALLOW_IDLE_EXIT|P_DIRTY_IS_DIRTY|P_DIRTY_TERMINATED)) == (P_DIRTY_ALLOW_IDLE_EXIT)) {
+                               /* Clean; issue SIGKILL */
+                               p->p_dirty |= P_DIRTY_TERMINATED;
+                               kill = TRUE;
+                       }
+                       proc_dirty_end(p);
+                       if (TRUE == kill) {
+                               printf("memorystatus_thread: idle exiting pid %d [%s]\n", victim_pid, (p->p_comm ? p->p_comm : "(unknown)"));
+                               psignal(p, SIGKILL);
+                       }
+                       proc_rele(p);
+               }
+       }
 
-       (void)kernel_thread(kernel_task, kern_memorystatus_thread);
+       assert_wait(&memorystatus_wakeup, THREAD_UNINT);
+       (void)thread_block((thread_continue_t)memorystatus_thread);
 }
 
+#if CONFIG_JETSAM
+
 static uint32_t
-jetsam_task_page_count(task_t task)
+memorystatus_task_page_count(task_t task)
 {
        kern_return_t ret;
        static task_info_data_t data;
@@ -104,267 +929,964 @@ jetsam_task_page_count(task_t task)
        return 0;
 }
 
+static int
+memorystatus_send_note(int event_code, void *data, size_t data_length) {
+       int ret;
+       struct kev_msg ev_msg;
+       
+       ev_msg.vendor_code    = KEV_VENDOR_APPLE;
+       ev_msg.kev_class      = KEV_SYSTEM_CLASS;
+       ev_msg.kev_subclass   = KEV_MEMORYSTATUS_SUBCLASS;
+
+       ev_msg.event_code     = event_code;
+
+       ev_msg.dv[0].data_length = data_length;
+       ev_msg.dv[0].data_ptr = data;
+       ev_msg.dv[1].data_length = 0;
+
+       ret = kev_post_msg(&ev_msg);
+       if (ret) {
+               memorystatus_kev_failure_count++;
+               printf("%s: kev_post_msg() failed, err %d\n", __func__, ret);
+       }
+       
+    return ret;
+}
+
 static uint32_t
-jetsam_flags_for_pid(pid_t pid)
+memorystatus_build_flags_from_state(uint32_t state) {
+    uint32_t flags = 0;
+    
+    if (state & kProcessForeground) {
+        flags |= kMemorystatusFlagsFrontmost;
+    }
+    if (state & kProcessActive) {
+        flags |= kMemorystatusFlagsActive;
+    }
+    if (state & kProcessSupportsIdleExit) {
+        flags |= kMemorystatusFlagsSupportsIdleExit;
+    }
+    if (state & kProcessDirty) {
+        flags |= kMemorystatusFlagsDirty;
+    }
+    
+    return flags;
+}
+
+static void 
+memorystatus_move_node_to_exit_list(memorystatus_node *node) 
 {
-       int i;
+       /* Make sure we're called with the list lock held */
+       lck_mtx_assert(memorystatus_list_mlock, LCK_MTX_ASSERT_OWNED);
+    
+       /* Now, acquire the exit list lock... */
+       lck_mtx_lock(exit_list_mlock);
+       
+       /* Remove from list + update accounting... */
+       memorystatus_remove_node(node);
+       
+       /* ...then insert at the end of the exit queue */
+       TAILQ_INSERT_TAIL(&exit_list, node, link);
+       
+       /* And relax */
+       lck_mtx_unlock(exit_list_mlock);
+}
 
-       for (i = 0; i < jetsam_priority_list_count; i++) {
-               if (pid == jetsam_priority_list[i].pid) {
-                       return jetsam_priority_list[i].flags;
+void memorystatus_update(unsigned int pages_avail)
+{        
+       if (!memorystatus_delta) {
+           return;
+       }
+                     
+       if ((pages_avail < memorystatus_available_pages_critical) ||
+            (pages_avail >= (memorystatus_available_pages + memorystatus_delta)) ||
+            (memorystatus_available_pages >= (pages_avail + memorystatus_delta))) {
+               memorystatus_available_pages = pages_avail;
+               memorystatus_level = memorystatus_available_pages * 100 / atop_64(max_mem);
+               /* Only wake the thread if currently blocked */
+               if (OSCompareAndSwap(0, 1, &memorystatus_jetsam_running)) {
+                       thread_wakeup((event_t)&memorystatus_jetsam_wakeup);
                }
        }
-       return 0;
+}
+
+static boolean_t
+memorystatus_get_snapshot_properties_for_proc_locked(proc_t p, memorystatus_jetsam_snapshot_entry_t *entry)
+{      
+       memorystatus_node *node;
+    
+       TAILQ_FOREACH(node, &memorystatus_list, link) {
+               if (node->pid == p->p_pid) {
+                       break;
+               }
+       }
+       
+       if (!node) {
+               return FALSE;
+       }
+       
+       entry->pid = p->p_pid;
+       strlcpy(&entry->name[0], p->p_comm, MAXCOMLEN+1);
+       entry->priority = node->priority;
+       entry->pages = memorystatus_task_page_count(p->task);
+       entry->flags = memorystatus_build_flags_from_state(node->state);
+       memcpy(&entry->uuid[0], &p->p_uuid[0], sizeof(p->p_uuid));
+
+       return TRUE;    
 }
 
 static void
-jetsam_snapshot_procs(void)
+memorystatus_jetsam_snapshot_procs_locked(void)
 {
        proc_t p;
        int i = 0;
 
-       jetsam_snapshot.stats.free_pages = vm_page_free_count;
-       jetsam_snapshot.stats.active_pages = vm_page_active_count;
-       jetsam_snapshot.stats.inactive_pages = vm_page_inactive_count;
-       jetsam_snapshot.stats.purgeable_pages = vm_page_purgeable_count;
-       jetsam_snapshot.stats.wired_pages = vm_page_wire_count;
+       memorystatus_jetsam_snapshot.stats.free_pages = vm_page_free_count;
+       memorystatus_jetsam_snapshot.stats.active_pages = vm_page_active_count;
+       memorystatus_jetsam_snapshot.stats.inactive_pages = vm_page_inactive_count;
+       memorystatus_jetsam_snapshot.stats.throttled_pages = vm_page_throttled_count;
+       memorystatus_jetsam_snapshot.stats.purgeable_pages = vm_page_purgeable_count;
+       memorystatus_jetsam_snapshot.stats.wired_pages = vm_page_wire_count;
        proc_list_lock();
        LIST_FOREACH(p, &allproc, p_list) {
-               task_t task = p->task;
-               jetsam_snapshot_list[i].pid = p->p_pid;
-               jetsam_snapshot_list[i].pages = jetsam_task_page_count(task);
-               jetsam_snapshot_list[i].flags = jetsam_flags_for_pid(p->p_pid);
-               strlcpy(&jetsam_snapshot_list[i].name[0], p->p_comm, MAXCOMLEN+1);
-#ifdef DEBUG
-               printf("jetsam snapshot pid = %d, uuid = %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+               if (FALSE == memorystatus_get_snapshot_properties_for_proc_locked(p, &memorystatus_jetsam_snapshot_list[i])) {
+                       continue;
+               }
+               
+               MEMORYSTATUS_DEBUG(0, "jetsam snapshot pid = %d, uuid = %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
                        p->p_pid, 
                        p->p_uuid[0], p->p_uuid[1], p->p_uuid[2], p->p_uuid[3], p->p_uuid[4], p->p_uuid[5], p->p_uuid[6], p->p_uuid[7],
                        p->p_uuid[8], p->p_uuid[9], p->p_uuid[10], p->p_uuid[11], p->p_uuid[12], p->p_uuid[13], p->p_uuid[14], p->p_uuid[15]);
-#endif
-               memcpy(&jetsam_snapshot_list[i].uuid[0], &p->p_uuid[0], sizeof(p->p_uuid));
-               i++;
-               if (i == kMaxSnapshotEntries) {
+
+               if (++i == kMaxSnapshotEntries) {
                        break;
                }       
        }
        proc_list_unlock();     
-       jetsam_snapshot.entry_count = jetsam_snapshot_list_count = i - 1;
+       memorystatus_jetsam_snapshot.snapshot_time = mach_absolute_time();
+       memorystatus_jetsam_snapshot.entry_count = memorystatus_jetsam_snapshot_list_count = i - 1;
 }
 
 static void
-jetsam_mark_pid_in_snapshot(pid_t pid)
+memorystatus_mark_pid_in_snapshot(pid_t pid, int flags)
 {
-
        int i = 0;
 
-       for (i = 0; i < jetsam_snapshot_list_count; i++) {
-               if (jetsam_snapshot_list[i].pid == pid) {
-                       jetsam_snapshot_list[i].flags |= kJetsamFlagsKilled;
+       for (i = 0; i < memorystatus_jetsam_snapshot_list_count; i++) {
+               if (memorystatus_jetsam_snapshot_list[i].pid == pid) {
+                       memorystatus_jetsam_snapshot_list[i].flags |= flags;
                        return;
                }
        }
 }
 
-static int
-jetsam_kill_top_proc(void)
+int
+memorystatus_kill_top_proc(boolean_t any, uint32_t cause)
 {
        proc_t p;
+       int pending_snapshot = 0;
 
-       if (jetsam_snapshot_list_count == 0) {
-               jetsam_snapshot_procs();
+#ifndef CONFIG_FREEZE
+#pragma unused(any)
+#endif
+       
+       lck_mtx_lock(memorystatus_list_mlock);
+
+       if (memorystatus_jetsam_snapshot_list_count == 0) {
+               memorystatus_jetsam_snapshot_procs_locked();
+       } else {
+               pending_snapshot = 1;
        }
-       lck_mtx_lock(jetsam_list_mlock);
-       while (jetsam_priority_list_index < jetsam_priority_list_count) {
+
+       while (next_memorystatus_node) {
+               memorystatus_node *node;
                pid_t aPid;
-               aPid = jetsam_priority_list[jetsam_priority_list_index].pid;
-               jetsam_priority_list_index++;
+#if DEVELOPMENT || DEBUG
+               int activeProcess;
+               int procSuspendedForDiagnosis;
+#endif /* DEVELOPMENT || DEBUG */
+
+               node = next_memorystatus_node;
+               next_memorystatus_node = TAILQ_NEXT(next_memorystatus_node, link);
+
+#if DEVELOPMENT || DEBUG
+               activeProcess = node->state & kProcessForeground;
+               procSuspendedForDiagnosis = node->state & kProcessSuspendedForDiag;
+#endif /* DEVELOPMENT || DEBUG */
+               
+               aPid = node->pid;
+
                /* skip empty slots in the list */
-               if (aPid == 0) {
+               if (aPid == 0  || (node->state & kProcessKilled)) {
                        continue; // with lock held
                }
-               lck_mtx_unlock(jetsam_list_mlock);
-               jetsam_mark_pid_in_snapshot(aPid);
+
                p = proc_find(aPid);
                if (p != NULL) {
-#if DEBUG
-                       printf("jetsam: killing pid %d [%s] - memory_status_level: %d - ", aPid, p->p_comm, kern_memorystatus_level);
-#endif /* DEBUG */
-                       exit1(p, W_EXITCODE(0, SIGKILL), (int *)NULL);
-                       proc_rele(p);
-#if DEBUG
-                       printf("jetsam: pid %d killed - memory_status_level: %d\n", aPid, kern_memorystatus_level);
-#endif /* DEBUG */
-                       return 0;
+                       int flags = cause;
+                       
+#if DEVELOPMENT || DEBUG
+                       if ((memorystatus_jetsam_policy & kPolicyDiagnoseActive) && procSuspendedForDiagnosis) {
+                               printf("jetsam: continuing after ignoring proc suspended already for diagnosis - %d\n", aPid);
+                               proc_rele(p);
+                               continue;
+                       }
+#endif /* DEVELOPMENT || DEBUG */
+
+#if CONFIG_FREEZE
+                       boolean_t skip;
+                       boolean_t reclaim_proc = !(node->state & (kProcessLocked | kProcessNoReclaimWorth));
+                       if (any || reclaim_proc) {
+                               if (node->state & kProcessFrozen) {
+                                       flags |= kMemorystatusFlagsFrozen;
+                               }
+                               skip = FALSE;
+                       } else {
+                               skip = TRUE;
+                       }
+                       
+                       if (skip) {
+                               proc_rele(p);                   
+                       } else
+#endif
+                       {
+#if DEVELOPMENT || DEBUG
+                               if ((memorystatus_jetsam_policy & kPolicyDiagnoseActive) && activeProcess) {
+                                       MEMORYSTATUS_DEBUG(1, "jetsam: suspending pid %d [%s] (active) for diagnosis - memory_status_level: %d\n",
+                                               aPid, (p->p_comm ? p->p_comm: "(unknown)"), memorystatus_level);
+                                       memorystatus_mark_pid_in_snapshot(aPid, kMemorystatusFlagsSuspForDiagnosis);
+                                       node->state |= kProcessSuspendedForDiag;
+                                       if (memorystatus_jetsam_policy & kPolicyDiagnoseFirst) {
+                                               jetsam_diagnostic_suspended_one_active_proc = 1;
+                                               printf("jetsam: returning after suspending first active proc - %d\n", aPid);
+                                       }
+                                       lck_mtx_unlock(memorystatus_list_mlock);
+                                       task_suspend(p->task);
+                                       proc_rele(p);
+                                       return 0;
+                               } else
+#endif /* DEVELOPMENT || DEBUG */
+                               {
+                                       printf("memorystatus: jetsam killing pid %d [%s] - memorystatus_available_pages: %d\n", 
+                                               aPid, (p->p_comm ? p->p_comm : "(unknown)"), memorystatus_available_pages);
+                                       /* Shift queue, update stats */
+                                       memorystatus_move_node_to_exit_list(node);
+                                       memorystatus_mark_pid_in_snapshot(aPid, flags);
+                                       lck_mtx_unlock(memorystatus_list_mlock);
+                                       exit1_internal(p, W_EXITCODE(0, SIGKILL), (int *)NULL, FALSE, FALSE);
+                                       proc_rele(p);
+                                       return 0;
+                               }
+                       }
+               }
+       }
+       
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       // If we didn't kill anything, toss any newly-created snapshot
+       if (!pending_snapshot) {
+           memorystatus_jetsam_snapshot.entry_count = memorystatus_jetsam_snapshot_list_count = 0;
+       }
+       
+       return -1;
+}
+
+int memorystatus_kill_top_proc_from_VM(void) {
+       return memorystatus_kill_top_proc(TRUE, kMemorystatusFlagsKilledVM);
+}
+
+static int
+memorystatus_kill_hiwat_proc(void)
+{
+       proc_t p;
+       int pending_snapshot = 0;
+       memorystatus_node *next_hiwat_node;
+       
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if (memorystatus_jetsam_snapshot_list_count == 0) {
+               memorystatus_jetsam_snapshot_procs_locked();
+       } else {
+               pending_snapshot = 1;
+       }
+       
+       next_hiwat_node = next_memorystatus_node;
+       
+       while (next_hiwat_node) {
+               pid_t aPid;
+               int32_t hiwat;
+               memorystatus_node *node;
+        
+               node = next_hiwat_node;
+               next_hiwat_node = TAILQ_NEXT(next_hiwat_node, link);
+               
+               aPid = node->pid;
+               hiwat = node->hiwat_pages;
+               
+               /* skip empty or non-hiwat slots in the list */
+               if (aPid == 0 || (hiwat < 0) || (node->state & kProcessKilled)) {
+                       continue; // with lock held
+               }
+               
+               p = proc_find(aPid);
+               if (p != NULL) {
+                       int32_t pages = (int32_t)memorystatus_task_page_count(p->task);
+                       boolean_t skip = (pages <= hiwat);
+#if DEVELOPMENT || DEBUG
+                       if (!skip && (memorystatus_jetsam_policy & kPolicyDiagnoseActive)) {
+                               if (node->state & kProcessSuspendedForDiag) {
+                                       proc_rele(p);
+                                       continue;
+                               }
+                       }
+#endif /* DEVELOPMENT || DEBUG */
+
+#if CONFIG_FREEZE
+                       if (!skip) {
+                               if (node->state & kProcessLocked) {
+                                       skip = TRUE;
+                               } else {
+                                       skip = FALSE;
+                               }                               
+                       }
+#endif
+
+                       if (!skip) {
+                               MEMORYSTATUS_DEBUG(1, "jetsam: %s pid %d [%s] - %d pages > 1 (%d)\n",
+                                       (memorystatus_jetsam_policy & kPolicyDiagnoseActive) ? "suspending": "killing", aPid, p->p_comm, pages, hiwat);
+#if DEVELOPMENT || DEBUG
+                               if (memorystatus_jetsam_policy & kPolicyDiagnoseActive) {
+                                   memorystatus_mark_pid_in_snapshot(aPid, kMemorystatusFlagsSuspForDiagnosis);
+                                       node->state |= kProcessSuspendedForDiag;
+                                       lck_mtx_unlock(memorystatus_list_mlock);
+                                       task_suspend(p->task);
+                                       proc_rele(p);
+                                       MEMORYSTATUS_DEBUG(1, "jetsam: pid %d suspended for diagnosis - memorystatus_available_pages: %d\n", aPid, memorystatus_available_pages);
+                               } else
+#endif /* DEVELOPMENT || DEBUG */
+                               {       
+                                       printf("memorystatus: jetsam killing pid %d [%s] (highwater) - memorystatus_available_pages: %d\n", 
+                                               aPid, (p->p_comm ? p->p_comm : "(unknown)"), memorystatus_available_pages);
+                                       /* Shift queue, update stats */
+                                       memorystatus_move_node_to_exit_list(node);
+                                       memorystatus_mark_pid_in_snapshot(aPid, kMemorystatusFlagsKilledHiwat);
+                                       lck_mtx_unlock(memorystatus_list_mlock);                    
+                                       exit1(p, W_EXITCODE(0, SIGKILL), (int *)NULL);
+                                       proc_rele(p);
+                               }
+                               return 0;
+                       } else {
+                               proc_rele(p);
+                       }
+
                }
-           lck_mtx_lock(jetsam_list_mlock);
        }
-       lck_mtx_unlock(jetsam_list_mlock);
+       
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       // If we didn't kill anything, toss any newly-created snapshot
+       if (!pending_snapshot) {
+               memorystatus_jetsam_snapshot.entry_count = memorystatus_jetsam_snapshot_list_count = 0;
+       }
+       
        return -1;
 }
 
 static void
-kern_memorystatus_thread(void)
+memorystatus_jetsam_thread_block(void)
 {
-       struct kev_msg ev_msg;
-       jetsam_kernel_stats_t data;
-       int ret;
+       assert_wait(&memorystatus_jetsam_wakeup, THREAD_UNINT);
+       assert(memorystatus_jetsam_running == 1);
+       OSDecrementAtomic(&memorystatus_jetsam_running);
+       (void)thread_block((thread_continue_t)memorystatus_jetsam_thread);   
+}
 
+static void
+memorystatus_jetsam_thread(void *param __unused, wait_result_t wr __unused)
+{
+       boolean_t post_snapshot = FALSE; 
+       static boolean_t is_vm_privileged = FALSE;
+
+       if (is_vm_privileged == FALSE) {
+               /* 
+                * It's the first time the thread has run, so just mark the thread as privileged and block.
+                * This avoids a spurious pass with unset variables, as set out in <rdar://problem/9609402>.
+                */
+               thread_wire(host_priv_self(), current_thread(), TRUE);
+               is_vm_privileged = TRUE;
+               memorystatus_jetsam_thread_block();
+       }
+       
+       assert(memorystatus_available_pages != (unsigned)-1);
+       
        while(1) {
+               unsigned int last_available_pages;
 
-               while (kern_memorystatus_level <= kern_memorystatus_level_critical) {
-                       if (jetsam_kill_top_proc() < 0) {
+#if DEVELOPMENT || DEBUG
+               jetsam_diagnostic_suspended_one_active_proc = 0;
+#endif /* DEVELOPMENT || DEBUG */
+           
+               while (memorystatus_available_pages <= memorystatus_available_pages_highwater) {
+                       if (memorystatus_kill_hiwat_proc() < 0) {
                                break;
                        }
+                       post_snapshot = TRUE;
+               }
+
+               while (memorystatus_available_pages <= memorystatus_available_pages_critical) {
+                       if (memorystatus_kill_top_proc(FALSE, kMemorystatusFlagsKilled) < 0) {
+                               /* No victim was found - panic */
+                               panic("memorystatus_jetsam_thread: no victim! available pages:%d, critical page level: %d\n",
+                                        memorystatus_available_pages, memorystatus_available_pages_critical);
+                       }
+                       post_snapshot = TRUE;
+#if DEVELOPMENT || DEBUG
+                       if ((memorystatus_jetsam_policy & kPolicyDiagnoseFirst) && jetsam_diagnostic_suspended_one_active_proc) {
+                               printf("jetsam: stopping killing since 1 active proc suspended already for diagnosis\n");
+                               break; // we found first active proc, let's not kill any more
+                       }
+#endif /* DEVELOPMENT || DEBUG */
                }
+               
+               last_available_pages = memorystatus_available_pages;
 
-               kern_memorystatus_last_level = kern_memorystatus_level;
+               if (post_snapshot) {
+                       size_t snapshot_size = sizeof(memorystatus_jetsam_snapshot_t) + sizeof(memorystatus_jetsam_snapshot_entry_t) * (memorystatus_jetsam_snapshot_list_count - 1);
+                       memorystatus_jetsam_snapshot.notification_time = mach_absolute_time();
+                       memorystatus_send_note(kMemorystatusSnapshotNote, &snapshot_size, sizeof(snapshot_size));
+               }
+
+               if (memorystatus_available_pages >= (last_available_pages + memorystatus_delta) ||
+                   last_available_pages >= (memorystatus_available_pages + memorystatus_delta)) {
+                       continue;
+               }
+
+#if VM_PRESSURE_EVENTS
+               memorystatus_check_pressure_reset();
+#endif
+
+               memorystatus_jetsam_thread_block();
+       }
+}
+
+#endif /* CONFIG_JETSAM */
+
+#if CONFIG_FREEZE
+
+__private_extern__ void
+memorystatus_freeze_init(void)
+{
+       kern_return_t result;
+       thread_t thread;
+       
+       result = kernel_thread_start(memorystatus_freeze_thread, NULL, &thread);
+       if (result == KERN_SUCCESS) {
+               thread_deallocate(thread);
+       } else {
+               panic("Could not create memorystatus_freeze_thread");
+       }
+}
 
-               ev_msg.vendor_code    = KEV_VENDOR_APPLE;
-               ev_msg.kev_class      = KEV_SYSTEM_CLASS;
-               ev_msg.kev_subclass   = KEV_MEMORYSTATUS_SUBCLASS;
+static int
+memorystatus_freeze_top_proc(boolean_t *memorystatus_freeze_swap_low)
+{
+       proc_t p;
+       uint32_t i;
+       memorystatus_node *next_freeze_node;
 
-               /* pass the memory status level (percent free) */
-               ev_msg.event_code     = kMemoryStatusLevelNote;
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       next_freeze_node = next_memorystatus_node;
+       
+       while (next_freeze_node) {
+               memorystatus_node *node;
+               pid_t aPid;
+               uint32_t state;
+               
+               node = next_freeze_node;
+               next_freeze_node = TAILQ_NEXT(next_freeze_node, link);
 
-               ev_msg.dv[0].data_length = sizeof kern_memorystatus_last_level;
-               ev_msg.dv[0].data_ptr = &kern_memorystatus_last_level;
-               ev_msg.dv[1].data_length = sizeof data;
-               ev_msg.dv[1].data_ptr = &data;
-               ev_msg.dv[2].data_length = 0;
+               aPid = node->pid;
+               state = node->state;
 
-               data.free_pages = vm_page_free_count;
-               data.active_pages = vm_page_active_count;
-               data.inactive_pages = vm_page_inactive_count;
-               data.purgeable_pages = vm_page_purgeable_count;
-               data.wired_pages = vm_page_wire_count;
+               /* skip empty slots in the list */
+               if (aPid == 0) {
+                       continue; // with lock held
+               }
 
-               ret = kev_post_msg(&ev_msg);
-               if (ret) {
-                       kern_memorystatus_kev_failure_count++;
-                       printf("%s: kev_post_msg() failed, err %d\n", __func__, ret);
+               /* Ensure the process is eligible for freezing */
+               if ((state & (kProcessKilled | kProcessLocked | kProcessFrozen)) || !(state & kProcessSuspended)) {
+                       continue; // with lock held
                }
 
-               if (jetsam_snapshot_list_count) {
-                       size_t snapshot_size =  sizeof(jetsam_kernel_stats_t) + sizeof(size_t) + sizeof(jetsam_snapshot_entry_t) * jetsam_snapshot_list_count;
-                       ev_msg.event_code = kMemoryStatusSnapshotNote;
-                       ev_msg.dv[0].data_length = sizeof snapshot_size;
-                       ev_msg.dv[0].data_ptr = &snapshot_size;
-                       ev_msg.dv[1].data_length = 0;
+               p = proc_find(aPid);
+               if (p != NULL) {
+                       kern_return_t kr;
+                       uint32_t purgeable, wired, clean, dirty;
+                       boolean_t shared;
+                       uint32_t max_pages = 0;
+                                       
+                       /* Only freeze processes meeting our minimum resident page criteria */
+                       if (memorystatus_task_page_count(p->task) < memorystatus_freeze_pages_min) {
+                               proc_rele(p);
+                               continue;
+                       } 
 
-                       ret = kev_post_msg(&ev_msg);
-                       if (ret) {
-                               kern_memorystatus_kev_failure_count++;
-                               printf("%s: kev_post_msg() failed, err %d\n", __func__, ret);
+                       /* Ensure there's enough free space to freeze this process. */                  
+                       max_pages = MIN(default_pager_swap_pages_free(), memorystatus_freeze_pages_max);
+                       if (max_pages < memorystatus_freeze_pages_min) {
+                               *memorystatus_freeze_swap_low = TRUE;
+                               proc_rele(p);
+                               lck_mtx_unlock(memorystatus_list_mlock);
+                               return 0;
                        }
-               }
+                       
+                       /* Mark as locked temporarily to avoid kill */
+                       node->state |= kProcessLocked;
+                       
+                       kr = task_freeze(p->task, &purgeable, &wired, &clean, &dirty, max_pages, &shared, FALSE);
+                       
+                       MEMORYSTATUS_DEBUG(1, "memorystatus_freeze_top_proc: task_freeze %s for pid %d [%s] - "
+                       "memorystatus_pages: %d, purgeable: %d, wired: %d, clean: %d, dirty: %d, shared %d, free swap: %d\n", 
+                       (kr == KERN_SUCCESS) ? "SUCCEEDED" : "FAILED", aPid, (p->p_comm ? p->p_comm : "(unknown)"), 
+                       memorystatus_available_pages, purgeable, wired, clean, dirty, shared, default_pager_swap_pages_free());
+                       
+                       proc_rele(p);
+               
+                       node->state &= ~kProcessLocked;
+                       
+                       if (KERN_SUCCESS == kr) {
+                               memorystatus_freeze_entry_t data = { aPid, kMemorystatusFlagsFrozen, dirty };
+                               
+                               memorystatus_frozen_count++;
+                               
+                               node->state |= (kProcessFrozen | (shared ? 0: kProcessNoReclaimWorth));
+                       
+                               /* Update stats */
+                               for (i = 0; i < sizeof(throttle_intervals) / sizeof(struct throttle_interval_t); i++) {
+                               throttle_intervals[i].pageouts += dirty;
+                               }
+                       
+                               memorystatus_freeze_pageouts += dirty;
+                               memorystatus_freeze_count++;
 
-               if (kern_memorystatus_level >= kern_memorystatus_last_level + 5 ||
-                   kern_memorystatus_level <= kern_memorystatus_last_level - 5)
-                       continue;
+                               lck_mtx_unlock(memorystatus_list_mlock);
+
+                               memorystatus_send_note(kMemorystatusFreezeNote, &data, sizeof(data));
 
-               assert_wait(&kern_memorystatus_wakeup, THREAD_UNINT);
-               (void)thread_block((thread_continue_t)kern_memorystatus_thread);
+                               return dirty;
+                       }
+                       
+                       /* Failed; go round again */
+               }
        }
+       
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       return -1;
 }
 
-static int
-sysctl_io_variable(struct sysctl_req *req, void *pValue, size_t currentsize, size_t maxsize, size_t *newsize)
+static inline boolean_t 
+memorystatus_can_freeze_processes(void) 
 {
-    int error;
+       boolean_t ret;
+       
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if (memorystatus_suspended_count) {
+               uint32_t average_resident_pages, estimated_processes;
+        
+               /* Estimate the number of suspended processes we can fit */
+               average_resident_pages = memorystatus_suspended_resident_count / memorystatus_suspended_count;
+               estimated_processes = memorystatus_suspended_count +
+                       ((memorystatus_available_pages - memorystatus_available_pages_critical) / average_resident_pages);
 
-    /* Copy blob out */
-    error = SYSCTL_OUT(req, pValue, currentsize);
+               /* If it's predicted that no freeze will occur, lower the threshold temporarily */
+               if (estimated_processes <= FREEZE_SUSPENDED_THRESHOLD_DEFAULT) {
+                       memorystatus_freeze_suspended_threshold = FREEZE_SUSPENDED_THRESHOLD_LOW;
+               } else {
+                       memorystatus_freeze_suspended_threshold = FREEZE_SUSPENDED_THRESHOLD_DEFAULT;        
+               }
 
-    /* error or nothing to set */
-    if (error || !req->newptr)
-        return(error);
+               MEMORYSTATUS_DEBUG(1, "memorystatus_can_freeze_processes: %d suspended processes, %d average resident pages / process, %d suspended processes estimated\n", 
+                       memorystatus_suspended_count, average_resident_pages, estimated_processes);
+       
+               if ((memorystatus_suspended_count - memorystatus_frozen_count) > memorystatus_freeze_suspended_threshold) {
+                       ret = TRUE;
+               } else {
+                       ret = FALSE;
+               }
+       } else {
+               ret = FALSE;
+       }
+                               
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       return ret;
+}
 
-    if (req->newlen > maxsize) {
-               return EINVAL;
+static boolean_t 
+memorystatus_can_freeze(boolean_t *memorystatus_freeze_swap_low)
+{
+       /* Only freeze if we're sufficiently low on memory; this holds off freeze right
+          after boot,  and is generally is a no-op once we've reached steady state. */
+       if (memorystatus_available_pages > memorystatus_freeze_threshold) {
+               return FALSE;
+       }
+       
+       /* Check minimum suspended process threshold. */
+       if (!memorystatus_can_freeze_processes()) {
+               return FALSE;
        }
-       error = SYSCTL_IN(req, pValue, req->newlen);
 
-       if (!error) {
-               *newsize = req->newlen;
+       /* Is swap running low? */
+       if (*memorystatus_freeze_swap_low) {
+               /* If there's been no movement in free swap pages since we last attempted freeze, return. */
+               if (default_pager_swap_pages_free() < memorystatus_freeze_pages_min) {
+                       return FALSE;
+               }
+               
+               /* Pages have been freed - we can retry. */
+               *memorystatus_freeze_swap_low = FALSE;  
        }
+       
+       /* OK */
+       return TRUE;
+}
+
+static void
+memorystatus_freeze_update_throttle_interval(mach_timespec_t *ts, struct throttle_interval_t *interval)
+{
+       if (CMP_MACH_TIMESPEC(ts, &interval->ts) >= 0) {
+               if (!interval->max_pageouts) {
+                       interval->max_pageouts = (interval->burst_multiple * (((uint64_t)interval->mins * FREEZE_DAILY_PAGEOUTS_MAX) / (24 * 60)));
+               } else {
+                       printf("memorystatus_freeze_update_throttle_interval: %d minute throttle timeout, resetting\n", interval->mins);
+               }
+               interval->ts.tv_sec = interval->mins * 60;
+               interval->ts.tv_nsec = 0;
+               ADD_MACH_TIMESPEC(&interval->ts, ts);
+               /* Since we update the throttle stats pre-freeze, adjust for overshoot here */
+               if (interval->pageouts > interval->max_pageouts) {
+                       interval->pageouts -= interval->max_pageouts;
+               } else {
+                       interval->pageouts = 0;
+               }
+               interval->throttle = FALSE;
+       } else if (!interval->throttle && interval->pageouts >= interval->max_pageouts) {
+               printf("memorystatus_freeze_update_throttle_interval: %d minute pageout limit exceeded; enabling throttle\n", interval->mins);
+               interval->throttle = TRUE;
+       }       
 
-    return(error);
+       MEMORYSTATUS_DEBUG(1, "memorystatus_freeze_update_throttle_interval: throttle updated - %d frozen (%d max) within %dm; %dm remaining; throttle %s\n", 
+               interval->pageouts, interval->max_pageouts, interval->mins, (interval->ts.tv_sec - ts->tv_sec) / 60, 
+               interval->throttle ? "on" : "off");
 }
 
-static int
-sysctl_handle_kern_memorystatus_priority_list(__unused struct sysctl_oid *oid, __unused void *arg1, __unused int arg2, struct sysctl_req *req)
+static boolean_t
+memorystatus_freeze_update_throttle(void) 
+{
+       clock_sec_t sec;
+       clock_nsec_t nsec;
+       mach_timespec_t ts;
+       uint32_t i;
+       boolean_t throttled = FALSE;
+
+#if DEVELOPMENT || DEBUG
+       if (!memorystatus_freeze_throttle_enabled)
+               return FALSE;
+#endif
+
+       clock_get_system_nanotime(&sec, &nsec);
+       ts.tv_sec = sec;
+       ts.tv_nsec = nsec;
+       
+       /* Check freeze pageouts over multiple intervals and throttle if we've exceeded our budget.
+        *
+        * This ensures that periods of inactivity can't be used as 'credit' towards freeze if the device has
+        * remained dormant for a long period. We do, however, allow increased thresholds for shorter intervals in
+        * order to allow for bursts of activity.
+        */
+       for (i = 0; i < sizeof(throttle_intervals) / sizeof(struct throttle_interval_t); i++) {
+               memorystatus_freeze_update_throttle_interval(&ts, &throttle_intervals[i]);
+               if (throttle_intervals[i].throttle == TRUE)
+                       throttled = TRUE;
+       }                                                               
+
+       return throttled;
+}
+
+static void
+memorystatus_freeze_thread(void *param __unused, wait_result_t wr __unused)
 {
-       int i, ret;
-       jetsam_priority_entry_t temp_list[kMaxPriorityEntries];
-       size_t newsize, currentsize;
+       static boolean_t memorystatus_freeze_swap_low = FALSE;
+       
+       if (memorystatus_freeze_enabled) {
+               if (memorystatus_can_freeze(&memorystatus_freeze_swap_low)) {
+                       /* Only freeze if we've not exceeded our pageout budgets */
+                       if (!memorystatus_freeze_update_throttle()) {
+                               memorystatus_freeze_top_proc(&memorystatus_freeze_swap_low);
+                       } else {
+                               printf("memorystatus_freeze_thread: in throttle, ignoring freeze\n");
+                               memorystatus_freeze_throttle_count++; /* Throttled, update stats */
+                       }
+               }
+       }
+
+       assert_wait((event_t) &memorystatus_freeze_wakeup, THREAD_UNINT);
+       thread_block((thread_continue_t) memorystatus_freeze_thread);   
+}
+
+#endif /* CONFIG_FREEZE */
+
+#if CONFIG_JETSAM
+
+#if VM_PRESSURE_EVENTS
+
+static inline boolean_t
+memorystatus_get_pressure_locked(void) {
+       if (memorystatus_available_pages > memorystatus_available_pages_pressure) {
+                /* Too many free pages */
+                return kVMPressureNormal;
+       }
+       
+#if CONFIG_FREEZE
+       if (memorystatus_frozen_count > 0) {
+                /* Frozen processes exist */
+                return kVMPressureNormal;              
+       }
+#endif
+
+       if (memorystatus_suspended_count > MEMORYSTATUS_SUSPENDED_THRESHOLD) {
+               /* Too many supended processes */
+               return kVMPressureNormal;
+       }
+       
+       if (memorystatus_suspended_count > 0) {
+               /* Some suspended processes - warn */
+               return kVMPressureWarning;
+       }
+    
+       /* Otherwise, pressure level is urgent */
+       return kVMPressureUrgent;
+}
+
+pid_t
+memorystatus_request_vm_pressure_candidate(void) {
+       memorystatus_node *node;
+       pid_t pid = -1;
+
+       lck_mtx_lock(memorystatus_list_mlock);
 
-       if (req->oldptr) {
-               lck_mtx_lock(jetsam_list_mlock);
-               for (i = 0; i < jetsam_priority_list_count; i++) {
-                       temp_list[i] = jetsam_priority_list[i];
+       /* Are we in a low memory state? */
+       memorystatus_vm_pressure_level = memorystatus_get_pressure_locked();
+       if (kVMPressureNormal != memorystatus_vm_pressure_level) {
+               TAILQ_FOREACH(node, &memorystatus_list, link) {
+                       /* Skip ineligible processes */
+                       if (node->state & (kProcessKilled | kProcessLocked | kProcessSuspended | kProcessFrozen | kProcessNotifiedForPressure)) {
+                               continue;
+                       }
+                       node->state |= kProcessNotifiedForPressure;
+                       pid = node->pid;
+                       break;
                }
-               lck_mtx_unlock(jetsam_list_mlock);
        }
+    
+       lck_mtx_unlock(memorystatus_list_mlock);
 
-       currentsize = sizeof(jetsam_priority_list[0]) * jetsam_priority_list_count;
+       return pid;
+}
 
-       ret = sysctl_io_variable(req, &temp_list[0], currentsize, sizeof(temp_list), &newsize);
+void
+memorystatus_send_pressure_note(pid_t pid) {
+    memorystatus_send_note(kMemorystatusPressureNote, &pid, sizeof(pid));
+}
 
-       if (!ret && req->newptr) {
-               jetsam_priority_list_count = newsize / sizeof(jetsam_priority_list[0]);
-#if DEBUG 
-               printf("set jetsam priority pids = { ");
-               for (i = 0; i < jetsam_priority_list_count; i++) {
-                       printf("%d ", temp_list[i].pid);
+static void
+memorystatus_check_pressure_reset() {        
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if (kVMPressureNormal != memorystatus_vm_pressure_level) {
+               memorystatus_vm_pressure_level = memorystatus_get_pressure_locked();
+               if (kVMPressureNormal == memorystatus_vm_pressure_level) {
+                       memorystatus_node *node;
+                       TAILQ_FOREACH(node, &memorystatus_list, link) {
+                               node->state &= ~kProcessNotifiedForPressure;
+                       }
                }
-               printf("}\n");
-#endif /* DEBUG */
-               lck_mtx_lock(jetsam_list_mlock);
-               for (i = 0; i < jetsam_priority_list_count; i++) {
-                       jetsam_priority_list[i] = temp_list[i];
+       }
+    
+       lck_mtx_unlock(memorystatus_list_mlock);
+}
+
+#endif /* VM_PRESSURE_EVENTS */
+
+/* Sysctls... */
+
+static int
+sysctl_memorystatus_list_change SYSCTL_HANDLER_ARGS
+{
+       int ret;
+       memorystatus_priority_entry_t entry;
+
+#pragma unused(oidp, arg1, arg2)
+
+       if (!req->newptr || req->newlen > sizeof(entry)) {
+               return EINVAL;
+       }
+
+       ret = SYSCTL_IN(req, &entry, req->newlen);
+       if (ret) {
+               return ret;
+       }
+
+       memorystatus_list_change(FALSE, entry.pid, entry.priority, entry.flags, -1);
+
+       return ret;
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_jetsam_change, CTLTYPE_INT|CTLFLAG_WR|CTLFLAG_LOCKED|CTLFLAG_MASKED,
+    0, 0, &sysctl_memorystatus_list_change, "I", "");
+    
+static int
+sysctl_memorystatus_priority_list(__unused struct sysctl_oid *oid, __unused void *arg1, __unused int arg2, struct sysctl_req *req)
+{
+       int ret;
+       size_t allocated_size, list_size = 0;
+       memorystatus_priority_entry_t *list;
+       uint32_t list_count, i = 0;
+       memorystatus_node *node;
+        
+       /* Races, but this is only for diagnostic purposes */
+       list_count = memorystatus_list_count;
+       allocated_size = sizeof(memorystatus_priority_entry_t) * list_count;
+       list = kalloc(allocated_size);
+       if (!list) {
+               return ENOMEM;
+       }
+
+       memset(list, 0, allocated_size);
+        
+       lck_mtx_lock(memorystatus_list_mlock);
+
+       TAILQ_FOREACH(node, &memorystatus_list, link) {
+               list[i].pid = node->pid;
+               list[i].priority = node->priority; 
+               list[i].flags = memorystatus_build_flags_from_state(node->state);
+               list[i].hiwat_pages = node->hiwat_pages;
+               list_size += sizeof(memorystatus_priority_entry_t);
+               if (++i >= list_count) {
+                       break;
+               }       
+       }
+       
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       if (!list_size) {
+               if (req->oldptr) {
+                       MEMORYSTATUS_DEBUG(1, "kern.memorystatus_priority_list returning EINVAL\n");
+                       return EINVAL;
                }
-               for (i = jetsam_priority_list_count; i < kMaxPriorityEntries; i++) {
-                       jetsam_priority_list[i].pid = 0;
-                       jetsam_priority_list[i].flags = 0;
+               else {
+                       MEMORYSTATUS_DEBUG(1, "kern.memorystatus_priority_list returning 0 for size\n");
                }
-               jetsam_priority_list_index = 0;
-               lck_mtx_unlock(jetsam_list_mlock);
-       }       
+       } else {
+               MEMORYSTATUS_DEBUG(1, "kern.memorystatus_priority_list returning %ld for size\n", (long)list_size);
+       }
+       
+       ret = SYSCTL_OUT(req, list, list_size);
+
+       kfree(list, allocated_size);
+       
        return ret;
 }
 
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_priority_list, CTLTYPE_OPAQUE|CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, sysctl_memorystatus_priority_list, "S,jetsam_priorities", "");
+
+static void
+memorystatus_update_levels_locked(void) {
+       /* Set the baseline levels in pages */
+       memorystatus_available_pages_critical = (CRITICAL_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+       memorystatus_available_pages_highwater = (HIGHWATER_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+#if VM_PRESSURE_EVENTS
+       memorystatus_available_pages_pressure = (PRESSURE_PERCENT / DELTA_PERCENT) * memorystatus_delta;
+#endif
+       
+#if DEBUG || DEVELOPMENT
+       if (memorystatus_jetsam_policy & kPolicyDiagnoseActive) {
+               memorystatus_available_pages_critical += memorystatus_jetsam_policy_offset_pages_diagnostic;
+               memorystatus_available_pages_highwater += memorystatus_jetsam_policy_offset_pages_diagnostic;
+#if VM_PRESSURE_EVENTS
+               memorystatus_available_pages_pressure += memorystatus_jetsam_policy_offset_pages_diagnostic;
+#endif
+       }
+#endif
+       
+       /* Only boost the critical level - it's more important to kill right away than issue warnings */
+       if (memorystatus_jetsam_policy & kPolicyMoreFree) {
+               memorystatus_available_pages_critical += memorystatus_jetsam_policy_offset_pages_more_free;
+       }
+}
+
+static int
+sysctl_memorystatus_jetsam_policy_more_free SYSCTL_HANDLER_ARGS
+{
+#pragma unused(arg1, arg2, oidp)
+       int error, more_free = 0;
+
+       error = priv_check_cred(kauth_cred_get(), PRIV_VM_JETSAM, 0);
+       if (error)
+               return (error);
+
+       error = sysctl_handle_int(oidp, &more_free, 0, req);
+       if (error || !req->newptr)
+               return (error);
+
+       lck_mtx_lock(memorystatus_list_mlock);
+       
+       if (more_free) {
+               memorystatus_jetsam_policy |= kPolicyMoreFree;
+       } else {
+               memorystatus_jetsam_policy &= ~kPolicyMoreFree;               
+       }
+        
+       memorystatus_update_levels_locked();
+               
+       lck_mtx_unlock(memorystatus_list_mlock);
+       
+       return 0;
+}
+
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_jetsam_policy_more_free, CTLTYPE_INT|CTLFLAG_WR|CTLFLAG_LOCKED|CTLFLAG_MASKED|CTLFLAG_ANYBODY,
+    0, 0, &sysctl_memorystatus_jetsam_policy_more_free, "I", "");
+
 static int
-sysctl_handle_kern_memorystatus_snapshot(__unused struct sysctl_oid *oid, __unused void *arg1, __unused int arg2, struct sysctl_req *req)
+sysctl_handle_memorystatus_snapshot(__unused struct sysctl_oid *oid, __unused void *arg1, __unused int arg2, struct sysctl_req *req)
 {
        int ret;
        size_t currentsize = 0;
 
-       if (jetsam_snapshot_list_count > 0) {
-               currentsize = sizeof(jetsam_kernel_stats_t) + sizeof(size_t) + sizeof(jetsam_snapshot_entry_t) * jetsam_snapshot_list_count;
+       if (memorystatus_jetsam_snapshot_list_count > 0) {
+               currentsize = sizeof(memorystatus_jetsam_snapshot_t) + sizeof(memorystatus_jetsam_snapshot_entry_t) * (memorystatus_jetsam_snapshot_list_count - 1);
        }
        if (!currentsize) {
                if (req->oldptr) {
-#ifdef DEBUG
-                       printf("kern.memorystatus_snapshot returning EINVAL\n");
-#endif
+                       MEMORYSTATUS_DEBUG(1, "kern.memorystatus_snapshot returning EINVAL\n");
                        return EINVAL;
                }
                else {
-#ifdef DEBUG
-                       printf("kern.memorystatus_snapshot returning 0 for size\n");
-#endif
+                       MEMORYSTATUS_DEBUG(1, "kern.memorystatus_snapshot returning 0 for size\n");
                }
        } else {
-#ifdef DEBUG
-                       printf("kern.memorystatus_snapshot returning %ld for size\n", (long)currentsize);
-#endif
+               MEMORYSTATUS_DEBUG(1, "kern.memorystatus_snapshot returning %ld for size\n", (long)currentsize);
        }       
-       ret = sysctl_io_variable(req, &jetsam_snapshot, currentsize, 0, NULL);
+       ret = SYSCTL_OUT(req, &memorystatus_jetsam_snapshot, currentsize);
        if (!ret && req->oldptr) {
-               jetsam_snapshot.entry_count = jetsam_snapshot_list_count = 0;
+               memorystatus_jetsam_snapshot.entry_count = memorystatus_jetsam_snapshot_list_count = 0;
        }
        return ret;
 }
 
-SYSCTL_PROC(_kern, OID_AUTO, memorystatus_priority_list, CTLTYPE_OPAQUE|CTLFLAG_RW, 0, 0, sysctl_handle_kern_memorystatus_priority_list, "S,jetsam_priorities", "");
-SYSCTL_PROC(_kern, OID_AUTO, memorystatus_snapshot, CTLTYPE_OPAQUE|CTLFLAG_RD, 0, 0, sysctl_handle_kern_memorystatus_snapshot, "S,jetsam_snapshot", "");
+SYSCTL_PROC(_kern, OID_AUTO, memorystatus_snapshot, CTLTYPE_OPAQUE|CTLFLAG_RD, 0, 0, sysctl_handle_memorystatus_snapshot, "S,memorystatus_snapshot", "");
+
+#endif /* CONFIG_JETSAM */