Imported Sun-Solaris-Kstat-1.3 from illumos Wed Apr 18 22:20:23 2012 +0000upstream/1.3upstream

1 files changed, 1690 insertions, 0 deletions

diff --git a/Kstat.xs b/Kstat.xs
new file mode 100644
index 0000000..403c95f
--- /dev/null
+++ b/Kstat.xs
@@ -0,0 +1,1690 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
+ */
+
+/*
+ * Kstat.xs is a Perl XS (eXStension module) that makes the Solaris
+ * kstat(3KSTAT) facility available to Perl scripts.  Kstat is a general-purpose
+ * mechanism  for  providing kernel statistics to users.  The Solaris API is
+ * function-based (see the manpage for details), but for ease of use in Perl
+ * scripts this module presents the information as a nested hash data structure.
+ * It would be too inefficient to read every kstat in the system, so this module
+ * uses the Perl TIEHASH mechanism to implement a read-on-demand semantic, which
+ * only reads and updates kstats as and when they are actually accessed.
+ */
+
+/*
+ * Ignored raw kstats.
+ *
+ * Some raw kstats are ignored by this module, these are listed below.  The
+ * most common reason is that the kstats are stored as arrays and the ks_ndata
+ * and/or ks_data_size fields are invalid.  In this case it is impossible to
+ * know how many records are in the array, so they can't be read.
+ *
+ * unix:*:sfmmu_percpu_stat
+ * This is stored as an array with one entry per cpu.  Each element is of type
+ * struct sfmmu_percpu_stat.  The ks_ndata and ks_data_size fields are bogus.
+ *
+ * ufs directio:*:UFS DirectIO Stats
+ * The structure definition used for these kstats (ufs_directio_kstats) is in a
+ * C file (uts/common/fs/ufs/ufs_directio.c) rather than a header file, so it
+ * isn't accessible.
+ *
+ * qlc:*:statistics
+ * This is a third-party driver for which we don't have source.
+ *
+ * mm:*:phys_installed
+ * This is stored as an array of uint64_t, with each pair of values being the
+ * (address, size) of a memory segment.  The ks_ndata and ks_data_size fields
+ * are both zero.
+ *
+ * sockfs:*:sock_unix_list
+ * This is stored as an array with one entry per active socket.  Each element
+ * is of type struct k_sockinfo.  The ks_ndata and ks_data_size fields are both
+ * zero.
+ *
+ * Note that the ks_ndata and ks_data_size of many non-array raw kstats are
+ * also incorrect.  The relevant assertions are therefore commented out in the
+ * appropriate raw kstat read routines.
+ */
+
+/* Kstat related includes */
+#include <libgen.h>
+#include <kstat.h>
+#include <sys/var.h>
+#include <sys/utsname.h>
+#include <sys/sysinfo.h>
+#include <sys/flock.h>
+#include <sys/dnlc.h>
+#include <nfs/nfs.h>
+#include <nfs/nfs_clnt.h>
+
+/* Ultra-specific kstat includes */
+#ifdef __sparc
+#include <vm/hat_sfmmu.h>	/* from /usr/platform/sun4u/include */
+#include <sys/simmstat.h>	/* from /usr/platform/sun4u/include */
+#include <sys/sysctrl.h>	/* from /usr/platform/sun4u/include */
+#include <sys/fhc.h>		/* from /usr/include */
+#endif
+
+/*
+ * Solaris #defines SP, which conflicts with the perl definition of SP
+ * We don't need the Solaris one, so get rid of it to avoid warnings
+ */
+#undef SP
+
+/* Perl XS includes */
+#include "EXTERN.h"
+#include "perl.h"
+#include "XSUB.h"
+
+/* Debug macros */
+#define	DEBUG_ID "Sun::Solaris::Kstat"
+#ifdef KSTAT_DEBUG
+#define	PERL_ASSERT(EXP) \
+    ((void)((EXP) || (croak("%s: assertion failed at %s:%d: %s", \
+    DEBUG_ID, __FILE__, __LINE__, #EXP), 0), 0))
+#define	PERL_ASSERTMSG(EXP, MSG) \
+    ((void)((EXP) || (croak(DEBUG_ID ": " MSG), 0), 0))
+#else
+#define	PERL_ASSERT(EXP)		((void)0)
+#define	PERL_ASSERTMSG(EXP, MSG)	((void)0)
+#endif
+
+/* Macros for saving the contents of KSTAT_RAW structures */
+#if defined(HAS_QUAD) && defined(USE_64_BIT_INT)
+#define NEW_IV(V) \
+    (newSViv((IVTYPE) V))
+#define NEW_UV(V) \
+    (newSVuv((UVTYPE) V))
+#else
+#define NEW_IV(V) \
+    (V >= IV_MIN && V <= IV_MAX ? newSViv((IVTYPE) V) : newSVnv((NVTYPE) V))
+#if defined(UVTYPE)
+#define NEW_UV(V) \
+    (V <= UV_MAX ? newSVuv((UVTYPE) V) : newSVnv((NVTYPE) V))
+# else
+#define NEW_UV(V) \
+    (V <= IV_MAX ? newSViv((IVTYPE) V) : newSVnv((NVTYPE) V))
+#endif
+#endif
+#define	NEW_HRTIME(V) \
+    newSVnv((NVTYPE) (V / 1000000000.0))
+
+#define	SAVE_FNP(H, F, K) \
+    hv_store(H, K, sizeof (K) - 1, newSViv((IVTYPE)(uintptr_t)&F), 0)
+#define	SAVE_STRING(H, S, K, SS) \
+    hv_store(H, #K, sizeof (#K) - 1, \
+    newSVpvn(S->K, SS ? strlen(S->K) : sizeof(S->K)), 0)
+#define	SAVE_INT32(H, S, K) \
+    hv_store(H, #K, sizeof (#K) - 1, NEW_IV(S->K), 0)
+#define	SAVE_UINT32(H, S, K) \
+    hv_store(H, #K, sizeof (#K) - 1, NEW_UV(S->K), 0)
+#define	SAVE_INT64(H, S, K) \
+    hv_store(H, #K, sizeof (#K) - 1, NEW_IV(S->K), 0)
+#define	SAVE_UINT64(H, S, K) \
+    hv_store(H, #K, sizeof (#K) - 1, NEW_UV(S->K), 0)
+#define	SAVE_HRTIME(H, S, K) \
+    hv_store(H, #K, sizeof (#K) - 1, NEW_HRTIME(S->K), 0)
+
+/* Private structure used for saving kstat info in the tied hashes */
+typedef struct {
+	char		read;		/* Kstat block has been read before */
+	char		valid;		/* Kstat still exists in kstat chain */
+	char		strip_str;	/* Strip KSTAT_DATA_CHAR fields */
+	kstat_ctl_t	*kstat_ctl;	/* Handle returned by kstat_open */
+	kstat_t		*kstat;		/* Handle used by kstat_read */
+} KstatInfo_t;
+
+/* typedef for apply_to_ties callback functions */
+typedef int (*ATTCb_t)(HV *, void *);
+
+/* typedef for raw kstat reader functions */
+typedef void (*kstat_raw_reader_t)(HV *, kstat_t *, int);
+
+/* Hash of "module:name" to KSTAT_RAW read functions */
+static HV *raw_kstat_lookup;
+
+/*
+ * Kstats come in two flavours, named and raw.  Raw kstats are just C structs,
+ * so we need a function per raw kstat to convert the C struct into the
+ * corresponding perl hash.  All such conversion functions are in the following
+ * section.
+ */
+
+/*
+ * Definitions in /usr/include/sys/cpuvar.h and /usr/include/sys/sysinfo.h
+ */
+
+static void
+save_cpu_stat(HV *self, kstat_t *kp, int strip_str)
+{
+	cpu_stat_t    *statp;
+	cpu_sysinfo_t *sysinfop;
+	cpu_syswait_t *syswaitp;
+	cpu_vminfo_t  *vminfop;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (cpu_stat_t));
+	statp = (cpu_stat_t *)(kp->ks_data);
+	sysinfop = &statp->cpu_sysinfo;
+	syswaitp = &statp->cpu_syswait;
+	vminfop  = &statp->cpu_vminfo;
+
+	hv_store(self, "idle", 4, NEW_UV(sysinfop->cpu[CPU_IDLE]), 0);
+	hv_store(self, "user", 4, NEW_UV(sysinfop->cpu[CPU_USER]), 0);
+	hv_store(self, "kernel", 6, NEW_UV(sysinfop->cpu[CPU_KERNEL]), 0);
+	hv_store(self, "wait", 4, NEW_UV(sysinfop->cpu[CPU_WAIT]), 0);
+	hv_store(self, "wait_io", 7, NEW_UV(sysinfop->wait[W_IO]), 0);
+	hv_store(self, "wait_swap", 9, NEW_UV(sysinfop->wait[W_SWAP]), 0);
+	hv_store(self, "wait_pio",  8, NEW_UV(sysinfop->wait[W_PIO]), 0);
+	SAVE_UINT32(self, sysinfop, bread);
+	SAVE_UINT32(self, sysinfop, bwrite);
+	SAVE_UINT32(self, sysinfop, lread);
+	SAVE_UINT32(self, sysinfop, lwrite);
+	SAVE_UINT32(self, sysinfop, phread);
+	SAVE_UINT32(self, sysinfop, phwrite);
+	SAVE_UINT32(self, sysinfop, pswitch);
+	SAVE_UINT32(self, sysinfop, trap);
+	SAVE_UINT32(self, sysinfop, intr);
+	SAVE_UINT32(self, sysinfop, syscall);
+	SAVE_UINT32(self, sysinfop, sysread);
+	SAVE_UINT32(self, sysinfop, syswrite);
+	SAVE_UINT32(self, sysinfop, sysfork);
+	SAVE_UINT32(self, sysinfop, sysvfork);
+	SAVE_UINT32(self, sysinfop, sysexec);
+	SAVE_UINT32(self, sysinfop, readch);
+	SAVE_UINT32(self, sysinfop, writech);
+	SAVE_UINT32(self, sysinfop, rcvint);
+	SAVE_UINT32(self, sysinfop, xmtint);
+	SAVE_UINT32(self, sysinfop, mdmint);
+	SAVE_UINT32(self, sysinfop, rawch);
+	SAVE_UINT32(self, sysinfop, canch);
+	SAVE_UINT32(self, sysinfop, outch);
+	SAVE_UINT32(self, sysinfop, msg);
+	SAVE_UINT32(self, sysinfop, sema);
+	SAVE_UINT32(self, sysinfop, namei);
+	SAVE_UINT32(self, sysinfop, ufsiget);
+	SAVE_UINT32(self, sysinfop, ufsdirblk);
+	SAVE_UINT32(self, sysinfop, ufsipage);
+	SAVE_UINT32(self, sysinfop, ufsinopage);
+	SAVE_UINT32(self, sysinfop, inodeovf);
+	SAVE_UINT32(self, sysinfop, fileovf);
+	SAVE_UINT32(self, sysinfop, procovf);
+	SAVE_UINT32(self, sysinfop, intrthread);
+	SAVE_UINT32(self, sysinfop, intrblk);
+	SAVE_UINT32(self, sysinfop, idlethread);
+	SAVE_UINT32(self, sysinfop, inv_swtch);
+	SAVE_UINT32(self, sysinfop, nthreads);
+	SAVE_UINT32(self, sysinfop, cpumigrate);
+	SAVE_UINT32(self, sysinfop, xcalls);
+	SAVE_UINT32(self, sysinfop, mutex_adenters);
+	SAVE_UINT32(self, sysinfop, rw_rdfails);
+	SAVE_UINT32(self, sysinfop, rw_wrfails);
+	SAVE_UINT32(self, sysinfop, modload);
+	SAVE_UINT32(self, sysinfop, modunload);
+	SAVE_UINT32(self, sysinfop, bawrite);
+#ifdef STATISTICS	/* see header file */
+	SAVE_UINT32(self, sysinfop, rw_enters);
+	SAVE_UINT32(self, sysinfop, win_uo_cnt);
+	SAVE_UINT32(self, sysinfop, win_uu_cnt);
+	SAVE_UINT32(self, sysinfop, win_so_cnt);
+	SAVE_UINT32(self, sysinfop, win_su_cnt);
+	SAVE_UINT32(self, sysinfop, win_suo_cnt);
+#endif
+
+	SAVE_INT32(self, syswaitp, iowait);
+	SAVE_INT32(self, syswaitp, swap);
+	SAVE_INT32(self, syswaitp, physio);
+
+	SAVE_UINT32(self, vminfop, pgrec);
+	SAVE_UINT32(self, vminfop, pgfrec);
+	SAVE_UINT32(self, vminfop, pgin);
+	SAVE_UINT32(self, vminfop, pgpgin);
+	SAVE_UINT32(self, vminfop, pgout);
+	SAVE_UINT32(self, vminfop, pgpgout);
+	SAVE_UINT32(self, vminfop, swapin);
+	SAVE_UINT32(self, vminfop, pgswapin);
+	SAVE_UINT32(self, vminfop, swapout);
+	SAVE_UINT32(self, vminfop, pgswapout);
+	SAVE_UINT32(self, vminfop, zfod);
+	SAVE_UINT32(self, vminfop, dfree);
+	SAVE_UINT32(self, vminfop, scan);
+	SAVE_UINT32(self, vminfop, rev);
+	SAVE_UINT32(self, vminfop, hat_fault);
+	SAVE_UINT32(self, vminfop, as_fault);
+	SAVE_UINT32(self, vminfop, maj_fault);
+	SAVE_UINT32(self, vminfop, cow_fault);
+	SAVE_UINT32(self, vminfop, prot_fault);
+	SAVE_UINT32(self, vminfop, softlock);
+	SAVE_UINT32(self, vminfop, kernel_asflt);
+	SAVE_UINT32(self, vminfop, pgrrun);
+	SAVE_UINT32(self, vminfop, execpgin);
+	SAVE_UINT32(self, vminfop, execpgout);
+	SAVE_UINT32(self, vminfop, execfree);
+	SAVE_UINT32(self, vminfop, anonpgin);
+	SAVE_UINT32(self, vminfop, anonpgout);
+	SAVE_UINT32(self, vminfop, anonfree);
+	SAVE_UINT32(self, vminfop, fspgin);
+	SAVE_UINT32(self, vminfop, fspgout);
+	SAVE_UINT32(self, vminfop, fsfree);
+}
+
+/*
+ * Definitions in /usr/include/sys/var.h
+ */
+
+static void
+save_var(HV *self, kstat_t *kp, int strip_str)
+{
+	struct var *varp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct var));
+	varp = (struct var *)(kp->ks_data);
+
+	SAVE_INT32(self, varp, v_buf);
+	SAVE_INT32(self, varp, v_call);
+	SAVE_INT32(self, varp, v_proc);
+	SAVE_INT32(self, varp, v_maxupttl);
+	SAVE_INT32(self, varp, v_nglobpris);
+	SAVE_INT32(self, varp, v_maxsyspri);
+	SAVE_INT32(self, varp, v_clist);
+	SAVE_INT32(self, varp, v_maxup);
+	SAVE_INT32(self, varp, v_hbuf);
+	SAVE_INT32(self, varp, v_hmask);
+	SAVE_INT32(self, varp, v_pbuf);
+	SAVE_INT32(self, varp, v_sptmap);
+	SAVE_INT32(self, varp, v_maxpmem);
+	SAVE_INT32(self, varp, v_autoup);
+	SAVE_INT32(self, varp, v_bufhwm);
+}
+
+/*
+ * Definition in /usr/include/sys/dnlc.h
+ */
+
+static void
+save_ncstats(HV *self, kstat_t *kp, int strip_str)
+{
+	struct ncstats *ncstatsp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct ncstats));
+	ncstatsp = (struct ncstats *)(kp->ks_data);
+
+	SAVE_INT32(self, ncstatsp, hits);
+	SAVE_INT32(self, ncstatsp, misses);
+	SAVE_INT32(self, ncstatsp, enters);
+	SAVE_INT32(self, ncstatsp, dbl_enters);
+	SAVE_INT32(self, ncstatsp, long_enter);
+	SAVE_INT32(self, ncstatsp, long_look);
+	SAVE_INT32(self, ncstatsp, move_to_front);
+	SAVE_INT32(self, ncstatsp, purges);
+}
+
+/*
+ * Definition in  /usr/include/sys/sysinfo.h
+ */
+
+static void
+save_sysinfo(HV *self, kstat_t *kp, int strip_str)
+{
+	sysinfo_t *sysinfop;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (sysinfo_t));
+	sysinfop = (sysinfo_t *)(kp->ks_data);
+
+	SAVE_UINT32(self, sysinfop, updates);
+	SAVE_UINT32(self, sysinfop, runque);
+	SAVE_UINT32(self, sysinfop, runocc);
+	SAVE_UINT32(self, sysinfop, swpque);
+	SAVE_UINT32(self, sysinfop, swpocc);
+	SAVE_UINT32(self, sysinfop, waiting);
+}
+
+/*
+ * Definition in  /usr/include/sys/sysinfo.h
+ */
+
+static void
+save_vminfo(HV *self, kstat_t *kp, int strip_str)
+{
+	vminfo_t *vminfop;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (vminfo_t));
+	vminfop = (vminfo_t *)(kp->ks_data);
+
+	SAVE_UINT64(self, vminfop, freemem);
+	SAVE_UINT64(self, vminfop, swap_resv);
+	SAVE_UINT64(self, vminfop, swap_alloc);
+	SAVE_UINT64(self, vminfop, swap_avail);
+	SAVE_UINT64(self, vminfop, swap_free);
+	SAVE_UINT64(self, vminfop, updates);
+}
+
+/*
+ * Definition in /usr/include/nfs/nfs_clnt.h
+ */
+
+static void
+save_nfs(HV *self, kstat_t *kp, int strip_str)
+{
+	struct mntinfo_kstat *mntinfop;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct mntinfo_kstat));
+	mntinfop = (struct mntinfo_kstat *)(kp->ks_data);
+
+	SAVE_STRING(self, mntinfop, mik_proto, strip_str);
+	SAVE_UINT32(self, mntinfop, mik_vers);
+	SAVE_UINT32(self, mntinfop, mik_flags);
+	SAVE_UINT32(self, mntinfop, mik_secmod);
+	SAVE_UINT32(self, mntinfop, mik_curread);
+	SAVE_UINT32(self, mntinfop, mik_curwrite);
+	SAVE_INT32(self, mntinfop, mik_timeo);
+	SAVE_INT32(self, mntinfop, mik_retrans);
+	SAVE_UINT32(self, mntinfop, mik_acregmin);
+	SAVE_UINT32(self, mntinfop, mik_acregmax);
+	SAVE_UINT32(self, mntinfop, mik_acdirmin);
+	SAVE_UINT32(self, mntinfop, mik_acdirmax);
+	hv_store(self, "lookup_srtt", 11,
+	    NEW_UV(mntinfop->mik_timers[0].srtt), 0);
+	hv_store(self, "lookup_deviate", 14,
+	    NEW_UV(mntinfop->mik_timers[0].deviate), 0);
+	hv_store(self, "lookup_rtxcur", 13,
+	    NEW_UV(mntinfop->mik_timers[0].rtxcur), 0);
+	hv_store(self, "read_srtt", 9,
+	    NEW_UV(mntinfop->mik_timers[1].srtt), 0);
+	hv_store(self, "read_deviate", 12,
+	    NEW_UV(mntinfop->mik_timers[1].deviate), 0);
+	hv_store(self, "read_rtxcur", 11,
+	    NEW_UV(mntinfop->mik_timers[1].rtxcur), 0);
+	hv_store(self, "write_srtt", 10,
+	    NEW_UV(mntinfop->mik_timers[2].srtt), 0);
+	hv_store(self, "write_deviate", 13,
+	    NEW_UV(mntinfop->mik_timers[2].deviate), 0);
+	hv_store(self, "write_rtxcur", 12,
+	    NEW_UV(mntinfop->mik_timers[2].rtxcur), 0);
+	SAVE_UINT32(self, mntinfop, mik_noresponse);
+	SAVE_UINT32(self, mntinfop, mik_failover);
+	SAVE_UINT32(self, mntinfop, mik_remap);
+	SAVE_STRING(self, mntinfop, mik_curserver, strip_str);
+}
+
+/*
+ * The following struct => hash functions are all only present on the sparc
+ * platform, so they are all conditionally compiled depending on __sparc
+ */
+
+/*
+ * Definition in /usr/platform/sun4u/include/vm/hat_sfmmu.h
+ */
+
+#ifdef __sparc
+static void
+save_sfmmu_global_stat(HV *self, kstat_t *kp, int strip_str)
+{
+	struct sfmmu_global_stat *sfmmugp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct sfmmu_global_stat));
+	sfmmugp = (struct sfmmu_global_stat *)(kp->ks_data);
+
+	SAVE_INT32(self, sfmmugp, sf_tsb_exceptions);
+	SAVE_INT32(self, sfmmugp, sf_tsb_raise_exception);
+	SAVE_INT32(self, sfmmugp, sf_pagefaults);
+	SAVE_INT32(self, sfmmugp, sf_uhash_searches);
+	SAVE_INT32(self, sfmmugp, sf_uhash_links);
+	SAVE_INT32(self, sfmmugp, sf_khash_searches);
+	SAVE_INT32(self, sfmmugp, sf_khash_links);
+	SAVE_INT32(self, sfmmugp, sf_swapout);
+	SAVE_INT32(self, sfmmugp, sf_tsb_alloc);
+	SAVE_INT32(self, sfmmugp, sf_tsb_allocfail);
+	SAVE_INT32(self, sfmmugp, sf_tsb_sectsb_create);
+	SAVE_INT32(self, sfmmugp, sf_scd_1sttsb_alloc);
+	SAVE_INT32(self, sfmmugp, sf_scd_2ndtsb_alloc);
+	SAVE_INT32(self, sfmmugp, sf_scd_1sttsb_allocfail);
+	SAVE_INT32(self, sfmmugp, sf_scd_2ndtsb_allocfail);
+	SAVE_INT32(self, sfmmugp, sf_tteload8k);
+	SAVE_INT32(self, sfmmugp, sf_tteload64k);
+	SAVE_INT32(self, sfmmugp, sf_tteload512k);
+	SAVE_INT32(self, sfmmugp, sf_tteload4m);
+	SAVE_INT32(self, sfmmugp, sf_tteload32m);
+	SAVE_INT32(self, sfmmugp, sf_tteload256m);
+	SAVE_INT32(self, sfmmugp, sf_tsb_load8k);
+	SAVE_INT32(self, sfmmugp, sf_tsb_load4m);
+	SAVE_INT32(self, sfmmugp, sf_hblk_hit);
+	SAVE_INT32(self, sfmmugp, sf_hblk8_ncreate);
+	SAVE_INT32(self, sfmmugp, sf_hblk8_nalloc);
+	SAVE_INT32(self, sfmmugp, sf_hblk1_ncreate);
+	SAVE_INT32(self, sfmmugp, sf_hblk1_nalloc);
+	SAVE_INT32(self, sfmmugp, sf_hblk_slab_cnt);
+	SAVE_INT32(self, sfmmugp, sf_hblk_reserve_cnt);
+	SAVE_INT32(self, sfmmugp, sf_hblk_recurse_cnt);
+	SAVE_INT32(self, sfmmugp, sf_hblk_reserve_hit);
+	SAVE_INT32(self, sfmmugp, sf_get_free_success);
+	SAVE_INT32(self, sfmmugp, sf_get_free_throttle);
+	SAVE_INT32(self, sfmmugp, sf_get_free_fail);
+	SAVE_INT32(self, sfmmugp, sf_put_free_success);
+	SAVE_INT32(self, sfmmugp, sf_put_free_fail);
+	SAVE_INT32(self, sfmmugp, sf_pgcolor_conflict);
+	SAVE_INT32(self, sfmmugp, sf_uncache_conflict);
+	SAVE_INT32(self, sfmmugp, sf_unload_conflict);
+	SAVE_INT32(self, sfmmugp, sf_ism_uncache);
+	SAVE_INT32(self, sfmmugp, sf_ism_recache);
+	SAVE_INT32(self, sfmmugp, sf_recache);
+	SAVE_INT32(self, sfmmugp, sf_steal_count);
+	SAVE_INT32(self, sfmmugp, sf_pagesync);
+	SAVE_INT32(self, sfmmugp, sf_clrwrt);
+	SAVE_INT32(self, sfmmugp, sf_pagesync_invalid);
+	SAVE_INT32(self, sfmmugp, sf_kernel_xcalls);
+	SAVE_INT32(self, sfmmugp, sf_user_xcalls);
+	SAVE_INT32(self, sfmmugp, sf_tsb_grow);
+	SAVE_INT32(self, sfmmugp, sf_tsb_shrink);
+	SAVE_INT32(self, sfmmugp, sf_tsb_resize_failures);
+	SAVE_INT32(self, sfmmugp, sf_tsb_reloc);
+	SAVE_INT32(self, sfmmugp, sf_user_vtop);
+	SAVE_INT32(self, sfmmugp, sf_ctx_inv);
+	SAVE_INT32(self, sfmmugp, sf_tlb_reprog_pgsz);
+	SAVE_INT32(self, sfmmugp, sf_region_remap_demap);
+	SAVE_INT32(self, sfmmugp, sf_create_scd);
+	SAVE_INT32(self, sfmmugp, sf_join_scd);
+	SAVE_INT32(self, sfmmugp, sf_leave_scd);
+	SAVE_INT32(self, sfmmugp, sf_destroy_scd);
+}
+#endif
+
+/*
+ * Definition in /usr/platform/sun4u/include/vm/hat_sfmmu.h
+ */
+
+#ifdef __sparc
+static void
+save_sfmmu_tsbsize_stat(HV *self, kstat_t *kp, int strip_str)
+{
+	struct sfmmu_tsbsize_stat *sfmmutp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct sfmmu_tsbsize_stat));
+	sfmmutp = (struct sfmmu_tsbsize_stat *)(kp->ks_data);
+
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_8k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_16k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_32k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_64k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_128k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_256k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_512k);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_1m);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_2m);
+	SAVE_INT32(self, sfmmutp, sf_tsbsz_4m);
+}
+#endif
+
+/*
+ * Definition in /usr/platform/sun4u/include/sys/simmstat.h
+ */
+
+#ifdef __sparc
+static void
+save_simmstat(HV *self, kstat_t *kp, int strip_str)
+{
+	uchar_t	*simmstatp;
+	SV	*list;
+	int	i;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (uchar_t) * SIMM_COUNT);
+
+	list = newSVpv("", 0);
+	for (i = 0, simmstatp = (uchar_t *)(kp->ks_data);
+	i < SIMM_COUNT - 1; i++, simmstatp++) {
+		sv_catpvf(list, "%d,", *simmstatp);
+	}
+	sv_catpvf(list, "%d", *simmstatp);
+	hv_store(self, "status", 6, list, 0);
+}
+#endif
+
+/*
+ * Used by save_temperature to make CSV lists from arrays of
+ * short temperature values
+ */
+
+#ifdef __sparc
+static SV *
+short_array_to_SV(short *shortp, int len)
+{
+	SV  *list;
+
+	list = newSVpv("", 0);
+	for (; len > 1; len--, shortp++) {
+		sv_catpvf(list, "%d,", *shortp);
+	}
+	sv_catpvf(list, "%d", *shortp);
+	return (list);
+}
+
+/*
+ * Definition in /usr/platform/sun4u/include/sys/fhc.h
+ */
+
+static void
+save_temperature(HV *self, kstat_t *kp, int strip_str)
+{
+	struct temp_stats *tempsp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (struct temp_stats));
+	tempsp = (struct temp_stats *)(kp->ks_data);
+
+	SAVE_UINT32(self, tempsp, index);
+	hv_store(self, "l1", 2, short_array_to_SV(tempsp->l1, L1_SZ), 0);
+	hv_store(self, "l2", 2, short_array_to_SV(tempsp->l2, L2_SZ), 0);
+	hv_store(self, "l3", 2, short_array_to_SV(tempsp->l3, L3_SZ), 0);
+	hv_store(self, "l4", 2, short_array_to_SV(tempsp->l4, L4_SZ), 0);
+	hv_store(self, "l5", 2, short_array_to_SV(tempsp->l5, L5_SZ), 0);
+	SAVE_INT32(self, tempsp, max);
+	SAVE_INT32(self, tempsp, min);
+	SAVE_INT32(self, tempsp, state);
+	SAVE_INT32(self, tempsp, temp_cnt);
+	SAVE_INT32(self, tempsp, shutdown_cnt);
+	SAVE_INT32(self, tempsp, version);
+	SAVE_INT32(self, tempsp, trend);
+	SAVE_INT32(self, tempsp, override);
+}
+#endif
+
+/*
+ * Not actually defined anywhere - just a short.  Yuck.
+ */
+
+#ifdef __sparc
+static void
+save_temp_over(HV *self, kstat_t *kp, int strip_str)
+{
+	short *shortp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == sizeof (short));
+
+	shortp = (short *)(kp->ks_data);
+	hv_store(self, "override", 8, newSViv(*shortp), 0);
+}
+#endif
+
+/*
+ * Defined in /usr/platform/sun4u/include/sys/sysctrl.h
+ * (Well, sort of.  Actually there's no structure, just a list of #defines
+ * enumerating *some* of the array indexes.)
+ */
+
+#ifdef __sparc
+static void
+save_ps_shadow(HV *self, kstat_t *kp, int strip_str)
+{
+	uchar_t *ucharp;
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	PERL_ASSERT(kp->ks_data_size == SYS_PS_COUNT);
+
+	ucharp = (uchar_t *)(kp->ks_data);
+	hv_store(self, "core_0", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_1", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_2", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_3", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_4", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_5", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_6", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "core_7", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "pps_0", 5, newSViv(*ucharp++), 0);
+	hv_store(self, "clk_33", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "clk_50", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "v5_p", 4, newSViv(*ucharp++), 0);
+	hv_store(self, "v12_p", 5, newSViv(*ucharp++), 0);
+	hv_store(self, "v5_aux", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "v5_p_pch", 8, newSViv(*ucharp++), 0);
+	hv_store(self, "v12_p_pch", 9, newSViv(*ucharp++), 0);
+	hv_store(self, "v3_pch", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "v5_pch", 6, newSViv(*ucharp++), 0);
+	hv_store(self, "p_fan", 5, newSViv(*ucharp++), 0);
+}
+#endif
+
+/*
+ * Definition in /usr/platform/sun4u/include/sys/fhc.h
+ */
+
+#ifdef __sparc
+static void
+save_fault_list(HV *self, kstat_t *kp, int strip_str)
+{
+	struct ft_list	*faultp;
+	int		i;
+	char		name[KSTAT_STRLEN + 7];	/* room for 999999 faults */
+
+	/* PERL_ASSERT(kp->ks_ndata == 1); */
+	/* PERL_ASSERT(kp->ks_data_size == sizeof (struct ft_list)); */
+
+	for (i = 1, faultp = (struct ft_list *)(kp->ks_data);
+	    i <= 999999 && i <= kp->ks_data_size / sizeof (struct ft_list);
+	    i++, faultp++) {
+		(void) snprintf(name, sizeof (name), "unit_%d", i);
+		hv_store(self, name, strlen(name), newSViv(faultp->unit), 0);
+		(void) snprintf(name, sizeof (name), "type_%d", i);
+		hv_store(self, name, strlen(name), newSViv(faultp->type), 0);
+		(void) snprintf(name, sizeof (name), "fclass_%d", i);
+		hv_store(self, name, strlen(name), newSViv(faultp->fclass), 0);
+		(void) snprintf(name, sizeof (name), "create_time_%d", i);
+		hv_store(self, name, strlen(name),
+		    NEW_UV(faultp->create_time), 0);
+		(void) snprintf(name, sizeof (name), "msg_%d", i);
+		hv_store(self, name, strlen(name), newSVpv(faultp->msg, 0), 0);
+	}
+}
+#endif
+
+/*
+ * We need to be able to find the function corresponding to a particular raw
+ * kstat.  To do this we ignore the instance and glue the module and name
+ * together to form a composite key.  We can then use the data in the kstat
+ * structure to find the appropriate function.  We use a perl hash to manage the
+ * lookup, where the key is "module:name" and the value is a pointer to the
+ * appropriate C function.
+ *
+ * Note that some kstats include the instance number as part of the module
+ * and/or name.  This could be construed as a bug.  However, to work around this
+ * we omit any digits from the module and name as we build the table in
+ * build_raw_kstat_loopup(), and we remove any digits from the module and name
+ * when we look up the functions in lookup_raw_kstat_fn()
+ */
+
+/*
+ * This function is called when the XS is first dlopen()ed, and builds the
+ * lookup table as described above.
+ */
+
+static void
+build_raw_kstat_lookup()
+	{
+	/* Create new hash */
+	raw_kstat_lookup = newHV();
+
+	SAVE_FNP(raw_kstat_lookup, save_cpu_stat, "cpu_stat:cpu_stat");
+	SAVE_FNP(raw_kstat_lookup, save_var, "unix:var");
+	SAVE_FNP(raw_kstat_lookup, save_ncstats, "unix:ncstats");
+	SAVE_FNP(raw_kstat_lookup, save_sysinfo, "unix:sysinfo");
+	SAVE_FNP(raw_kstat_lookup, save_vminfo, "unix:vminfo");
+	SAVE_FNP(raw_kstat_lookup, save_nfs, "nfs:mntinfo");
+#ifdef __sparc
+	SAVE_FNP(raw_kstat_lookup, save_sfmmu_global_stat,
+	    "unix:sfmmu_global_stat");
+	SAVE_FNP(raw_kstat_lookup, save_sfmmu_tsbsize_stat,
+	    "unix:sfmmu_tsbsize_stat");
+	SAVE_FNP(raw_kstat_lookup, save_simmstat, "unix:simm-status");
+	SAVE_FNP(raw_kstat_lookup, save_temperature, "unix:temperature");
+	SAVE_FNP(raw_kstat_lookup, save_temp_over, "unix:temperature override");
+	SAVE_FNP(raw_kstat_lookup, save_ps_shadow, "unix:ps_shadow");
+	SAVE_FNP(raw_kstat_lookup, save_fault_list, "unix:fault_list");
+#endif
+}
+
+/*
+ * This finds and returns the raw kstat reader function corresponding to the
+ * supplied module and name.  If no matching function exists, 0 is returned.
+ */
+
+static kstat_raw_reader_t lookup_raw_kstat_fn(char *module, char *name)
+	{
+	char			key[KSTAT_STRLEN * 2];
+	register char		*f, *t;
+	SV			**entry;
+	kstat_raw_reader_t	fnp;
+
+	/* Copy across module & name, removing any digits - see comment above */
+	for (f = module, t = key; *f != '\0'; f++, t++) {
+		while (*f != '\0' && isdigit(*f)) { f++; }
+		*t = *f;
+	}
+	*t++ = ':';
+	for (f = name; *f != '\0'; f++, t++) {
+		while (*f != '\0' && isdigit(*f)) {
+			f++;
+		}
+	*t = *f;
+	}
+	*t = '\0';
+
+	/* look up & return the function, or teturn 0 if not found */
+	if ((entry = hv_fetch(raw_kstat_lookup, key, strlen(key), FALSE)) == 0)
+	{
+		fnp = 0;
+	} else {
+		fnp = (kstat_raw_reader_t)(uintptr_t)SvIV(*entry);
+	}
+	return (fnp);
+}
+
+/*
+ * This module converts the flat list returned by kstat_read() into a perl hash
+ * tree keyed on module, instance, name and statistic.  The following functions
+ * provide code to create the nested hashes, and to iterate over them.
+ */
+
+/*
+ * Given module, instance and name keys return a pointer to the hash tied to
+ * the bottommost hash.  If the hash already exists, we just return a pointer
+ * to it, otherwise we create the hash and any others also required above it in
+ * the hierarchy.  The returned tiehash is blessed into the
+ * Sun::Solaris::Kstat::_Stat class, so that the appropriate TIEHASH methods are
+ * called when the bottommost hash is accessed.  If the is_new parameter is
+ * non-null it will be set to TRUE if a new tie has been created, and FALSE if
+ * the tie already existed.
+ */
+
+static HV *
+get_tie(SV *self, char *module, int instance, char *name, int *is_new)
+{
+	char str_inst[11];	/* big enough for up to 10^10 instances */
+	char *key[3];		/* 3 part key: module, instance, name */
+	int  k;
+	int  new;
+	HV   *hash;
+	HV   *tie;
+
+	/* Create the keys */
+	(void) snprintf(str_inst, sizeof (str_inst), "%d", instance);
+	key[0] = module;
+	key[1] = str_inst;
+	key[2] = name;
+
+	/* Iteratively descend the tree, creating new hashes as required */
+	hash = (HV *)SvRV(self);
+	for (k = 0; k < 3; k++) {
+		SV **entry;
+
+		SvREADONLY_off(hash);
+		entry = hv_fetch(hash, key[k], strlen(key[k]), TRUE);
+
+		/* If the entry doesn't exist, create it */
+		if (! SvOK(*entry)) {
+			HV *newhash;
+			SV *rv;
+
+			newhash = newHV();
+			rv = newRV_noinc((SV *)newhash);
+			sv_setsv(*entry, rv);
+			SvREFCNT_dec(rv);
+			if (k < 2) {
+				SvREADONLY_on(newhash);
+			}
+			SvREADONLY_on(*entry);
+			SvREADONLY_on(hash);
+			hash = newhash;
+			new = 1;
+
+		/* Otherwise it already existed */
+		} else {
+			SvREADONLY_on(hash);
+			hash = (HV *)SvRV(*entry);
+			new = 0;
+		}
+	}
+
+	/* Create and bless a hash for the tie, if necessary */
+	if (new) {
+		SV *tieref;
+		HV *stash;
+
+		tie = newHV();
+		tieref = newRV_noinc((SV *)tie);
+		stash = gv_stashpv("Sun::Solaris::Kstat::_Stat", TRUE);
+		sv_bless(tieref, stash);
+
+		/* Add TIEHASH magic */
+		hv_magic(hash, (GV *)tieref, 'P');
+		SvREADONLY_on(hash);
+
+	/* Otherwise, just find the existing tied hash */
+	} else {
+		MAGIC *mg;
+
+		mg = mg_find((SV *)hash, 'P');
+		PERL_ASSERTMSG(mg != 0, "get_tie: lost P magic");
+		tie = (HV *)SvRV(mg->mg_obj);
+	}
+	if (is_new) {
+		*is_new = new;
+	}
+	return (tie);
+}
+
+/*
+ * This is an iterator function used to traverse the hash hierarchy and apply
+ * the passed function to the tied hashes at the bottom of the hierarchy.  If
+ * any of the callback functions return 0, 0 is returned, otherwise 1
+ */
+
+static int
+apply_to_ties(SV *self, ATTCb_t cb, void *arg)
+{
+	HV	*hash1;
+	HE	*entry1;
+	long	s;
+	int	ret;
+
+	hash1 = (HV *)SvRV(self);
+	hv_iterinit(hash1);
+	ret = 1;
+
+	/* Iterate over each module */
+	while (entry1 = hv_iternext(hash1)) {
+		HV *hash2;
+		HE *entry2;
+
+		hash2 = (HV *)SvRV(hv_iterval(hash1, entry1));
+		hv_iterinit(hash2);
+
+		/* Iterate over each module:instance */
+		while (entry2 = hv_iternext(hash2)) {
+			HV *hash3;
+			HE *entry3;
+
+			hash3 = (HV *)SvRV(hv_iterval(hash2, entry2));
+			hv_iterinit(hash3);
+
+			/* Iterate over each module:instance:name */
+			while (entry3 = hv_iternext(hash3)) {
+				HV    *hash4;
+				MAGIC *mg;
+				HV    *tie;
+
+				/* Get the tie */
+				hash4 = (HV *)SvRV(hv_iterval(hash3, entry3));
+				mg = mg_find((SV *)hash4, 'P');
+				PERL_ASSERTMSG(mg != 0,
+				    "apply_to_ties: lost P magic");
+
+				/* Apply the callback */
+				if (! cb((HV *)SvRV(mg->mg_obj), arg)) {
+					ret = 0;
+				}
+			}
+		}
+	}
+	return (ret);
+}
+
+/*
+ * Mark this HV as valid - used by update() when pruning deleted kstat nodes
+ */
+
+static int
+set_valid(HV *self, void *arg)
+{
+	MAGIC *mg;
+
+	mg = mg_find((SV *)self, '~');
+	PERL_ASSERTMSG(mg != 0, "set_valid: lost ~ magic");
+	((KstatInfo_t *)SvPVX(mg->mg_obj))->valid = (int)(intptr_t)arg;
+	return (1);
+}
+
+/*
+ * Prune invalid kstat nodes. This is called when kstat_chain_update() detects
+ * that the kstat chain has been updated.  This removes any hash tree entries
+ * that no longer have a corresponding kstat.  If del is non-null it will be
+ * set to the keys of the deleted kstat nodes, if any.  If any entries are
+ * deleted 1 will be retured, otherwise 0
+ */
+
+static int
+prune_invalid(SV *self, AV *del)
+{
+	HV	*hash1;
+	HE	*entry1;
+	STRLEN	klen;
+	char	*module, *instance, *name, *key;
+	int	ret;
+
+	hash1 = (HV *)SvRV(self);
+	hv_iterinit(hash1);
+	ret = 0;
+
+	/* Iterate over each module */
+	while (entry1 = hv_iternext(hash1)) {
+		HV *hash2;
+		HE *entry2;
+
+		module = HePV(entry1, PL_na);
+		hash2 = (HV *)SvRV(hv_iterval(hash1, entry1));
+		hv_iterinit(hash2);
+
+		/* Iterate over each module:instance */
+		while (entry2 = hv_iternext(hash2)) {
+			HV *hash3;
+			HE *entry3;
+
+			instance = HePV(entry2, PL_na);
+			hash3 = (HV *)SvRV(hv_iterval(hash2, entry2));
+			hv_iterinit(hash3);
+
+			/* Iterate over each module:instance:name */
+			while (entry3 = hv_iternext(hash3)) {
+				HV    *hash4;
+				MAGIC *mg;
+				HV    *tie;
+
+				name = HePV(entry3, PL_na);
+				hash4 = (HV *)SvRV(hv_iterval(hash3, entry3));
+				mg = mg_find((SV *)hash4, 'P');
+				PERL_ASSERTMSG(mg != 0,
+				    "prune_invalid: lost P magic");
+				tie = (HV *)SvRV(mg->mg_obj);
+				mg = mg_find((SV *)tie, '~');
+				PERL_ASSERTMSG(mg != 0,
+				    "prune_invalid: lost ~ magic");
+
+				/* If this is marked as invalid, prune it */
+				if (((KstatInfo_t *)SvPVX(
+				    (SV *)mg->mg_obj))->valid == FALSE) {
+					SvREADONLY_off(hash3);
+					key = HePV(entry3, klen);
+					hv_delete(hash3, key, klen, G_DISCARD);
+					SvREADONLY_on(hash3);
+					if (del) {
+						av_push(del,
+						    newSVpvf("%s:%s:%s",
+						    module, instance, name));
+					}
+					ret = 1;
+				}
+			}
+
+			/* If the module:instance:name hash is empty prune it */
+			if (HvKEYS(hash3) == 0) {
+				SvREADONLY_off(hash2);
+				key = HePV(entry2, klen);
+				hv_delete(hash2, key, klen, G_DISCARD);
+				SvREADONLY_on(hash2);
+			}
+		}
+		/* If the module:instance hash is empty prune it */
+		if (HvKEYS(hash2) == 0) {
+			SvREADONLY_off(hash1);
+			key = HePV(entry1, klen);
+			hv_delete(hash1, key, klen, G_DISCARD);
+			SvREADONLY_on(hash1);
+		}
+	}
+	return (ret);
+}
+
+/*
+ * Named kstats are returned as a list of key/values.  This function converts
+ * such a list into the equivalent perl datatypes, and stores them in the passed
+ * hash.
+ */
+
+static void
+save_named(HV *self, kstat_t *kp, int strip_str)
+{
+	kstat_named_t	*knp;
+	int		n;
+	SV*		value;
+
+	for (n = kp->ks_ndata, knp = KSTAT_NAMED_PTR(kp); n > 0; n--, knp++) {
+		switch (knp->data_type) {
+		case KSTAT_DATA_CHAR:
+			value = newSVpv(knp->value.c, strip_str ?
+			    strlen(knp->value.c) : sizeof (knp->value.c));
+			break;
+		case KSTAT_DATA_INT32:
+			value = newSViv(knp->value.i32);
+			break;
+		case KSTAT_DATA_UINT32:
+			value = NEW_UV(knp->value.ui32);
+			break;
+		case KSTAT_DATA_INT64:
+			value = NEW_UV(knp->value.i64);
+			break;
+		case KSTAT_DATA_UINT64:
+			value = NEW_UV(knp->value.ui64);
+			break;
+		case KSTAT_DATA_STRING:
+			if (KSTAT_NAMED_STR_PTR(knp) == NULL)
+				value = newSVpv("null", sizeof ("null") - 1);
+			else
+				value = newSVpv(KSTAT_NAMED_STR_PTR(knp),
+						KSTAT_NAMED_STR_BUFLEN(knp) -1);
+			break;
+		default:
+			PERL_ASSERTMSG(0, "kstat_read: invalid data type");
+			break;
+		}
+		hv_store(self, knp->name, strlen(knp->name), value, 0);
+	}
+}
+
+/*
+ * Save kstat interrupt statistics
+ */
+
+static void
+save_intr(HV *self, kstat_t *kp, int strip_str)
+{
+	kstat_intr_t	*kintrp;
+	int		i;
+	static char	*intr_names[] =
+	    { "hard", "soft", "watchdog", "spurious", "multiple_service" };
+
+	PERL_ASSERT(kp->ks_ndata == 1);
+	PERL_ASSERT(kp->ks_data_size == sizeof (kstat_intr_t));
+	kintrp = KSTAT_INTR_PTR(kp);
+
+	for (i = 0; i < KSTAT_NUM_INTRS; i++) {
+		hv_store(self, intr_names[i], strlen(intr_names[i]),
+		    NEW_UV(kintrp->intrs[i]), 0);
+	}
+}
+
+/*
+ * Save IO statistics
+ */
+
+static void
+save_io(HV *self, kstat_t *kp, int strip_str)
+{
+	kstat_io_t *kiop;
+
+	PERL_ASSERT(kp->ks_ndata == 1);
+	PERL_ASSERT(kp->ks_data_size == sizeof (kstat_io_t));
+	kiop = KSTAT_IO_PTR(kp);
+	SAVE_UINT64(self, kiop, nread);
+	SAVE_UINT64(self, kiop, nwritten);
+	SAVE_UINT32(self, kiop, reads);
+	SAVE_UINT32(self, kiop, writes);
+	SAVE_HRTIME(self, kiop, wtime);
+	SAVE_HRTIME(self, kiop, wlentime);
+	SAVE_HRTIME(self, kiop, wlastupdate);
+	SAVE_HRTIME(self, kiop, rtime);
+	SAVE_HRTIME(self, kiop, rlentime);
+	SAVE_HRTIME(self, kiop, rlastupdate);
+	SAVE_UINT32(self, kiop, wcnt);
+	SAVE_UINT32(self, kiop, rcnt);
+}
+
+/*
+ * Save timer statistics
+ */
+
+static void
+save_timer(HV *self, kstat_t *kp, int strip_str)
+{
+	kstat_timer_t *ktimerp;
+
+	PERL_ASSERT(kp->ks_ndata == 1);
+	PERL_ASSERT(kp->ks_data_size == sizeof (kstat_timer_t));
+	ktimerp = KSTAT_TIMER_PTR(kp);
+	SAVE_STRING(self, ktimerp, name, strip_str);
+	SAVE_UINT64(self, ktimerp, num_events);
+	SAVE_HRTIME(self, ktimerp, elapsed_time);
+	SAVE_HRTIME(self, ktimerp, min_time);
+	SAVE_HRTIME(self, ktimerp, max_time);
+	SAVE_HRTIME(self, ktimerp, start_time);
+	SAVE_HRTIME(self, ktimerp, stop_time);
+}
+
+/*
+ * Read kstats and copy into the supplied perl hash structure.  If refresh is
+ * true, this function is being called as part of the update() method.  In this
+ * case it is only necessary to read the kstats if they have previously been
+ * accessed (kip->read == TRUE).  If refresh is false, this function is being
+ * called prior to returning a value to the caller. In this case, it is only
+ * necessary to read the kstats if they have not previously been read.  If the
+ * kstat_read() fails, 0 is returned, otherwise 1
+ */
+
+static int
+read_kstats(HV *self, int refresh)
+{
+	MAGIC			*mg;
+	KstatInfo_t		*kip;
+	kstat_raw_reader_t	fnp;
+
+	/* Find the MAGIC KstatInfo_t data structure */
+	mg = mg_find((SV *)self, '~');
+	PERL_ASSERTMSG(mg != 0, "read_kstats: lost ~ magic");
+	kip = (KstatInfo_t *)SvPVX(mg->mg_obj);
+
+	/* Return early if we don't need to actually read the kstats */
+	if ((refresh && ! kip->read) || (! refresh && kip->read)) {
+		return (1);
+	}
+
+	/* Read the kstats and return 0 if this fails */
+	if (kstat_read(kip->kstat_ctl, kip->kstat, NULL) < 0) {
+		return (0);
+	}
+
+	/* Save the read data */
+	hv_store(self, "snaptime", 8, NEW_HRTIME(kip->kstat->ks_snaptime), 0);
+	switch (kip->kstat->ks_type) {
+		case KSTAT_TYPE_RAW:
+			if ((fnp = lookup_raw_kstat_fn(kip->kstat->ks_module,
+			    kip->kstat->ks_name)) != 0) {
+				fnp(self, kip->kstat, kip->strip_str);
+			}
+			break;
+		case KSTAT_TYPE_NAMED:
+			save_named(self, kip->kstat, kip->strip_str);
+			break;
+		case KSTAT_TYPE_INTR:
+			save_intr(self, kip->kstat, kip->strip_str);
+			break;
+		case KSTAT_TYPE_IO:
+			save_io(self, kip->kstat, kip->strip_str);
+			break;
+		case KSTAT_TYPE_TIMER:
+			save_timer(self, kip->kstat, kip->strip_str);
+			break;
+		default:
+			PERL_ASSERTMSG(0, "read_kstats: illegal kstat type");
+			break;
+	}
+	kip->read = TRUE;
+	return (1);
+}
+
+/*
+ * The XS code exported to perl is below here.  Note that the XS preprocessor
+ * has its own commenting syntax, so all comments from this point on are in
+ * that form.
+ */
+
+/* The following XS methods are the ABI of the Sun::Solaris::Kstat package */
+
+MODULE = Sun::Solaris::Kstat PACKAGE = Sun::Solaris::Kstat
+PROTOTYPES: ENABLE
+
+ # Create the raw kstat to store function lookup table on load
+BOOT:
+	build_raw_kstat_lookup();
+
+ #
+ # The Sun::Solaris::Kstat constructor.  This builds the nested
+ # name::instance::module hash structure, but doesn't actually read the
+ # underlying kstats.  This is done on demand by the TIEHASH methods in
+ # Sun::Solaris::Kstat::_Stat
+ #
+
+SV*
+new(class, ...)
+	char *class;
+PREINIT:
+	HV		*stash;
+	kstat_ctl_t	*kc;
+	SV		*kcsv;
+	kstat_t		*kp;
+	KstatInfo_t	kstatinfo;
+	int		sp, strip_str;
+CODE:
+	/* Check we have an even number of arguments, excluding the class */
+	sp = 1;
+	if (((items - sp) % 2) != 0) {
+		croak(DEBUG_ID ": new: invalid number of arguments");
+	}
+
+	/* Process any (name => value) arguments */
+	strip_str = 0;
+	while (sp < items) {
+		SV *name, *value;
+
+		name = ST(sp);
+		sp++;
+		value = ST(sp);
+		sp++;
+		if (strcmp(SvPVX(name), "strip_strings") == 0) {
+			strip_str = SvTRUE(value);
+		} else {
+			croak(DEBUG_ID ": new: invalid parameter name '%s'",
+			    SvPVX(name));
+		}
+	}
+
+	/* Open the kstats handle */
+	if ((kc = kstat_open()) == 0) {
+		XSRETURN_UNDEF;
+	}
+
+	/* Create a blessed hash ref */
+	RETVAL = (SV *)newRV_noinc((SV *)newHV());
+	stash = gv_stashpv(class, TRUE);
+	sv_bless(RETVAL, stash);
+
+	/* Create a place to save the KstatInfo_t structure */
+	kcsv = newSVpv((char *)&kc, sizeof (kc));
+	sv_magic(SvRV(RETVAL), kcsv, '~', 0, 0);
+	SvREFCNT_dec(kcsv);
+
+	/* Initialise the KstatsInfo_t structure */
+	kstatinfo.read = FALSE;
+	kstatinfo.valid = TRUE;
+	kstatinfo.strip_str = strip_str;
+	kstatinfo.kstat_ctl = kc;
+
+	/* Scan the kstat chain, building hash entries for the kstats */
+	for (kp = kc->kc_chain; kp != 0; kp = kp->ks_next) {
+		HV *tie;
+		SV *kstatsv;
+
+		/* Don't bother storing the kstat headers */
+		if (strncmp(kp->ks_name, "kstat_", 6) == 0) {
+			continue;
+		}
+
+		/* Don't bother storing raw stats we don't understand */
+		if (kp->ks_type == KSTAT_TYPE_RAW &&
+		    lookup_raw_kstat_fn(kp->ks_module, kp->ks_name) == 0) {
+#ifdef REPORT_UNKNOWN
+			(void) fprintf(stderr,
+			    "Unknown kstat type %s:%d:%s - %d of size %d\n",
+			    kp->ks_module, kp->ks_instance, kp->ks_name,
+			    kp->ks_ndata, kp->ks_data_size);
+#endif
+			continue;
+		}
+
+		/* Create a 3-layer hash hierarchy - module.instance.name */
+		tie = get_tie(RETVAL, kp->ks_module, kp->ks_instance,
+		    kp->ks_name, 0);
+
+		/* Save the data necessary to read the kstat info on demand */
+		hv_store(tie, "class", 5, newSVpv(kp->ks_class, 0), 0);
+		hv_store(tie, "crtime", 6, NEW_HRTIME(kp->ks_crtime), 0);
+		kstatinfo.kstat = kp;
+		kstatsv = newSVpv((char *)&kstatinfo, sizeof (kstatinfo));
+		sv_magic((SV *)tie, kstatsv, '~', 0, 0);
+		SvREFCNT_dec(kstatsv);
+	}
+	SvREADONLY_on(SvRV(RETVAL));
+	/* SvREADONLY_on(RETVAL); */
+OUTPUT:
+	RETVAL
+
+ #
+ # Update the perl hash structure so that it is in line with the kernel kstats
+ # data.  Only kstats athat have previously been accessed are read,
+ #
+
+ # Scalar context: true/false
+ # Array context: (\@added, \@deleted)
+void
+update(self)
+	SV* self;
+PREINIT:
+	MAGIC		*mg;
+	kstat_ctl_t	*kc;
+	kstat_t		*kp;
+	int		ret;
+	AV		*add, *del;
+PPCODE:
+	/* Find the hidden KstatInfo_t structure */
+	mg = mg_find(SvRV(self), '~');
+	PERL_ASSERTMSG(mg != 0, "update: lost ~ magic");
+	kc = *(kstat_ctl_t **)SvPVX(mg->mg_obj);
+
+	/* Update the kstat chain, and return immediately on error. */
+	if ((ret = kstat_chain_update(kc)) == -1) {
+		if (GIMME_V == G_ARRAY) {
+			EXTEND(SP, 2);
+			PUSHs(sv_newmortal());
+			PUSHs(sv_newmortal());
+		} else {
+			EXTEND(SP, 1);
+			PUSHs(sv_2mortal(newSViv(ret)));
+		}
+	}
+
+	/* Create the arrays to be returned if in an array context */
+	if (GIMME_V == G_ARRAY) {
+		add = newAV();
+		del = newAV();
+	} else {
+		add = 0;
+		del = 0;
+	}
+
+	/*
+	 * If the kstat chain hasn't changed we can just reread any stats
+	 * that have already been read
+	 */
+	if (ret == 0) {
+		if (! apply_to_ties(self, (ATTCb_t)read_kstats, (void *)TRUE)) {
+			if (GIMME_V == G_ARRAY) {
+				EXTEND(SP, 2);
+				PUSHs(sv_2mortal(newRV_noinc((SV *)add)));
+				PUSHs(sv_2mortal(newRV_noinc((SV *)del)));
+			} else {
+				EXTEND(SP, 1);
+				PUSHs(sv_2mortal(newSViv(-1)));
+			}
+		}
+
+	/*
+	 * Otherwise we have to update the Perl structure so that it is in
+	 * agreement with the new kstat chain.  We do this in such a way as to
+	 * retain all the existing structures, just adding or deleting the
+	 * bare minimum.
+	 */
+	} else {
+		KstatInfo_t	kstatinfo;
+
+		/*
+		 * Step 1: set the 'invalid' flag on each entry
+		 */
+		apply_to_ties(self, &set_valid, (void *)FALSE);
+
+		/*
+		 * Step 2: Set the 'valid' flag on all entries still in the
+		 * kernel kstat chain
+		 */
+		kstatinfo.read		= FALSE;
+		kstatinfo.valid		= TRUE;
+		kstatinfo.kstat_ctl	= kc;
+		for (kp = kc->kc_chain; kp != 0; kp = kp->ks_next) {
+			int	new;
+			HV	*tie;
+
+			/* Don't bother storing the kstat headers or types */
+			if (strncmp(kp->ks_name, "kstat_", 6) == 0) {
+				continue;
+			}
+
+			/* Don't bother storing raw stats we don't understand */
+			if (kp->ks_type == KSTAT_TYPE_RAW &&
+			    lookup_raw_kstat_fn(kp->ks_module, kp->ks_name)
+			    == 0) {
+#ifdef REPORT_UNKNOWN
+				(void) printf("Unknown kstat type %s:%d:%s "
+				    "- %d of size %d\n", kp->ks_module,
+				    kp->ks_instance, kp->ks_name,
+				    kp->ks_ndata, kp->ks_data_size);
+#endif
+				continue;
+			}
+
+			/* Find the tied hash associated with the kstat entry */
+			tie = get_tie(self, kp->ks_module, kp->ks_instance,
+			    kp->ks_name, &new);
+
+			/* If newly created store the associated kstat info */
+			if (new) {
+				SV *kstatsv;
+
+				/*
+				 * Save the data necessary to read the kstat
+				 * info on demand
+				 */
+				hv_store(tie, "class", 5,
+				    newSVpv(kp->ks_class, 0), 0);
+				hv_store(tie, "crtime", 6,
+				    NEW_HRTIME(kp->ks_crtime), 0);
+				kstatinfo.kstat = kp;
+				kstatsv = newSVpv((char *)&kstatinfo,
+				    sizeof (kstatinfo));
+				sv_magic((SV *)tie, kstatsv, '~', 0, 0);
+				SvREFCNT_dec(kstatsv);
+
+				/* Save the key on the add list, if required */
+				if (GIMME_V == G_ARRAY) {
+					av_push(add, newSVpvf("%s:%d:%s",
+					    kp->ks_module, kp->ks_instance,
+					    kp->ks_name));
+				}
+
+			/* If the stats already exist, just update them */
+			} else {
+				MAGIC *mg;
+				KstatInfo_t *kip;
+
+				/* Find the hidden KstatInfo_t */
+				mg = mg_find((SV *)tie, '~');
+				PERL_ASSERTMSG(mg != 0, "update: lost ~ magic");
+				kip = (KstatInfo_t *)SvPVX(mg->mg_obj);
+
+				/* Mark the tie as valid */
+				kip->valid = TRUE;
+
+				/* Re-save the kstat_t pointer.  If the kstat
+				 * has been deleted and re-added since the last
+				 * update, the address of the kstat structure
+				 * will have changed, even though the kstat will
+				 * still live at the same place in the perl
+				 * hash tree structure.
+				 */
+				kip->kstat = kp;
+
+				/* Reread the stats, if read previously */
+				read_kstats(tie, TRUE);
+			}
+		}
+
+		/*
+		 *Step 3: Delete any entries still marked as 'invalid'
+		 */
+		ret = prune_invalid(self, del);
+
+	}
+	if (GIMME_V == G_ARRAY) {
+		EXTEND(SP, 2);
+		PUSHs(sv_2mortal(newRV_noinc((SV *)add)));
+		PUSHs(sv_2mortal(newRV_noinc((SV *)del)));
+	} else {
+		EXTEND(SP, 1);
+		PUSHs(sv_2mortal(newSViv(ret)));
+	}
+
+
+ #
+ # Destructor.  Closes the kstat connection
+ #
+
+void
+DESTROY(self)
+	SV *self;
+PREINIT:
+	MAGIC		*mg;
+	kstat_ctl_t	*kc;
+CODE:
+	mg = mg_find(SvRV(self), '~');
+	PERL_ASSERTMSG(mg != 0, "DESTROY: lost ~ magic");
+	kc = *(kstat_ctl_t **)SvPVX(mg->mg_obj);
+	if (kstat_close(kc) != 0) {
+		croak(DEBUG_ID ": kstat_close: failed");
+	}
+
+ #
+ # The following XS methods implement the TIEHASH mechanism used to update the
+ # kstats hash structure.  These are blessed into a package that isn't
+ # visible to callers of the Sun::Solaris::Kstat module
+ #
+
+MODULE = Sun::Solaris::Kstat PACKAGE = Sun::Solaris::Kstat::_Stat
+PROTOTYPES: ENABLE
+
+ #
+ # If a value has already been read, return it.  Otherwise read the appropriate
+ # kstat and then return the value
+ #
+
+SV*
+FETCH(self, key)
+	SV* self;
+	SV* key;
+PREINIT:
+	char	*k;
+	STRLEN	klen;
+	SV	**value;
+CODE:
+	self = SvRV(self);
+	k = SvPV(key, klen);
+	if (strNE(k, "class") && strNE(k, "crtime")) {
+		read_kstats((HV *)self, FALSE);
+	}
+	value = hv_fetch((HV *)self, k, klen, FALSE);
+	if (value) {
+		RETVAL = *value; SvREFCNT_inc(RETVAL);
+	} else {
+		RETVAL = &PL_sv_undef;
+	}
+OUTPUT:
+	RETVAL
+
+ #
+ # Save the passed value into the kstat hash.  Read the appropriate kstat first,
+ # if necessary.  Note that this DOES NOT update the underlying kernel kstat
+ # structure.
+ #
+
+SV*
+STORE(self, key, value)
+	SV* self;
+	SV* key;
+	SV* value;
+PREINIT:
+	char	*k;
+	STRLEN	klen;
+CODE:
+	self = SvRV(self);
+	k = SvPV(key, klen);
+	if (strNE(k, "class") && strNE(k, "crtime")) {
+		read_kstats((HV *)self, FALSE);
+	}
+	SvREFCNT_inc(value);
+	RETVAL = *(hv_store((HV *)self, k, klen, value, 0));
+	SvREFCNT_inc(RETVAL);
+OUTPUT:
+	RETVAL
+
+ #
+ # Check for the existence of the passed key.  Read the kstat first if necessary
+ #
+
+bool
+EXISTS(self, key)
+	SV* self;
+	SV* key;
+PREINIT:
+	char *k;
+CODE:
+	self = SvRV(self);
+	k = SvPV(key, PL_na);
+	if (strNE(k, "class") && strNE(k, "crtime")) {
+		read_kstats((HV *)self, FALSE);
+	}
+	RETVAL = hv_exists_ent((HV *)self, key, 0);
+OUTPUT:
+	RETVAL
+
+
+ #
+ # Hash iterator initialisation.  Read the kstats if necessary.
+ #
+
+SV*
+FIRSTKEY(self)
+	SV* self;
+PREINIT:
+	HE *he;
+PPCODE:
+	self = SvRV(self);
+	read_kstats((HV *)self, FALSE);
+	hv_iterinit((HV *)self);
+	if (he = hv_iternext((HV *)self)) {
+		EXTEND(SP, 1);
+		PUSHs(hv_iterkeysv(he));
+	}
+
+ #
+ # Return hash iterator next value.  Read the kstats if necessary.
+ #
+
+SV*
+NEXTKEY(self, lastkey)
+	SV* self;
+	SV* lastkey;
+PREINIT:
+	HE *he;
+PPCODE:
+	self = SvRV(self);
+	if (he = hv_iternext((HV *)self)) {
+		EXTEND(SP, 1);
+		PUSHs(hv_iterkeysv(he));
+	}
+
+
+ #
+ # Delete the specified hash entry.
+ #
+
+SV*
+DELETE(self, key)
+	SV *self;
+	SV *key;
+CODE:
+	self = SvRV(self);
+	RETVAL = hv_delete_ent((HV *)self, key, 0, 0);
+	if (RETVAL) {
+		SvREFCNT_inc(RETVAL);
+	} else {
+		RETVAL = &PL_sv_undef;
+	}
+OUTPUT:
+	RETVAL
+
+ #
+ # Clear the entire hash.  This will stop any update() calls rereading this
+ # kstat until it is accessed again.
+ #
+
+void
+CLEAR(self)
+	SV* self;
+PREINIT:
+	MAGIC   *mg;
+	KstatInfo_t *kip;
+CODE:
+	self = SvRV(self);
+	hv_clear((HV *)self);
+	mg = mg_find(self, '~');
+	PERL_ASSERTMSG(mg != 0, "CLEAR: lost ~ magic");
+	kip = (KstatInfo_t *)SvPVX(mg->mg_obj);
+	kip->read  = FALSE;
+	kip->valid = TRUE;
+	hv_store((HV *)self, "class", 5, newSVpv(kip->kstat->ks_class, 0), 0);
+	hv_store((HV *)self, "crtime", 6, NEW_HRTIME(kip->kstat->ks_crtime), 0);