2 files changed, 142 insertions, 0 deletions
diff --git a/system_cmds/mslutil/mslutil.1 b/system_cmds/mslutil/mslutil.1
new file mode 100644
index 0000000..ea4f068
--- /dev/null
+++ b/system_cmds/mslutil/mslutil.1
@@ -0,0 +1,46 @@
+.\" Copyright (c) 2017, Apple Computer, Inc.  All rights reserved.
+.\"
+.Dd March 31, 2017
+.Dt MSLUTIL 1
+.Os "Mac OS X"
+.Sh NAME
+.Nm mslutil
+.Nd Tool to enable / disable malloc stack logging on a specific proces
+.Sh SYNOPSIS
+.Nm mslutil pid [--enable flavor] | [--disable] 
+.Sh DESCRIPTION
+The
+.Nm mslutil
+utility enables/disables malloc stack logging on the process specified by 
+.Nm pid.
+It requires root privileges.
+.Pp
+The options are as follows:
+.Bl -tag -width Ds
+.\" ==========
+.It Fl -enable
+Specifying the
+.Fl -enable
+option enables malloc stack logging, using the 
+.Pa flavor
+provided.
+The supported flavors are:
+.Pp
+.Pa full		
+Standard malloc stack logging that records both vm and malloc calls
+.Pp
+.Pa malloc	
+Standard malloc stack logging that records only malloc calls
+.Pp
+.Pa vm		
+Standard malloc stack logging that records only vm calls
+.Pp
+.Pa lite		
+Lite mode of malloc stack logging.
+.\" ==========
+.It Fl -disable
+Specifying the
+.Fl -disable
+option disables any current mode of malloc stack logging.
+.\" ==========
+.El
diff --git a/system_cmds/mslutil/mslutil.c b/system_cmds/mslutil/mslutil.c
new file mode 100644
index 0000000..5738d4a
--- /dev/null
+++ b/system_cmds/mslutil/mslutil.c
@@ -0,0 +1,96 @@
+//
+//  mslutil.c
+//  mslutil
+//
+//  Created by Christopher Deppe on 3/31/17.
+//
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/sysctl.h>
+#include <stack_logging.h>
+
+#define    BSD_PID_MAX    99999        /* Copy of PID_MAX from sys/proc_internal.h. */
+
+static void print_usage()
+{
+    printf("usage: mslutil pid [--disable] | [--enable malloc | vm | full | lite | vmlite]\n");
+}
+
+static int send_msl_command(uint64_t pid, uint64_t flavor)
+{
+    uint64_t flags = flavor;
+    flags <<= 32;
+    
+    flags |= (pid & 0xFFFFFFFF);
+    
+    int ret = sysctlbyname("kern.memorystatus_vm_pressure_send", 0, 0, &flags, sizeof(flags));
+    
+    if (ret) {
+        printf("send_msl_command - sysctl: kern.memorystatus_vm_pressure_send failed %s\n", strerror(errno));
+    } else {
+        printf("send_msl_command - success!\n");
+    }
+    
+    return ret;
+}
+
+int main(int argc, const char * argv[])
+{
+    if (argc < 3) {
+        print_usage();
+        exit(1);
+    }
+    
+    int ret = -1;
+    
+    pid_t pid = atoi(argv[1]);
+    
+    if (pid <= 0 || pid > BSD_PID_MAX) {
+        printf("Invalid pid\n");
+        exit(1);
+    }
+    
+    if (strcmp(argv[2], "--enable") == 0) {
+        if (argc < 4) {
+            print_usage();
+            exit(1);
+        }
+        
+        uint64_t flavor = 0;
+        
+        if (strcmp(argv[3], "full") == 0) {
+            flavor = MEMORYSTATUS_ENABLE_MSL_MALLOC | MEMORYSTATUS_ENABLE_MSL_VM;
+        } else if (strcmp(argv[3], "malloc") == 0) {
+            flavor = MEMORYSTATUS_ENABLE_MSL_MALLOC;
+        } else if (strcmp(argv[3], "vm") == 0) {
+            flavor = MEMORYSTATUS_ENABLE_MSL_VM;
+        } else if (strcmp(argv[3], "lite") == 0) {
+            flavor = MEMORYSTATUS_ENABLE_MSL_LITE_FULL;
+        } else if (strcmp(argv[3], "vmlite") == 0) {
+            flavor = MEMORYSTATUS_ENABLE_MSL_LITE_VM;
+        }
+        
+        if (flavor == 0) {
+            print_usage();
+            exit(1);
+        }
+        
+        ret = send_msl_command(pid, flavor);
+    } else if (strcmp(argv[2], "--disable") == 0) {
+        ret = send_msl_command(pid, MEMORYSTATUS_DISABLE_MSL);
+    } else {
+        print_usage();
+        exit(1);
+    }
+    
+    if (ret != 0) {
+        exit(1);
+    } else {
+        exit(0);
+    }
+}
+
+