freebsd-skq/usr.sbin/pmcstat/pmcpl_calltree.c

/*-
 * Copyright (c) 2009, Fabien Thomas
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Process hwpmc(4) samples as calltree.
 *
 * Output file format compatible with Kcachegrind (kdesdk).
 * Handle top mode with a sorted tree display.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/endian.h>
#include <sys/queue.h>

#include <assert.h>
#include <curses.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <pmc.h>
#include <pmclog.h>
#include <sysexits.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sysexits.h>

#include "pmcstat.h"
#include "pmcstat_log.h"
#include "pmcstat_top.h"
#include "pmcpl_calltree.h"

#define PMCPL_CT_GROWSIZE	4

static pmcstat_interned_string pmcpl_ct_prevfn;

static int pmcstat_skiplink = 0;

struct pmcpl_ct_node;

/* Get the sample value for PMC a. */
#define PMCPL_CT_SAMPLE(a, b) \
	((a) < (b)->npmcs ? (b)->sb[a] : 0)

/* Get the sample value in percent related to rsamples. */
#define PMCPL_CT_SAMPLEP(a, b) \
	(PMCPL_CT_SAMPLE(a, b) * 100.0 / rsamples->sb[a])

struct pmcpl_ct_sample {
	int		npmcs;		/* Max pmc index available. */
	unsigned	*sb;		/* Sample buffer for 0..npmcs. */
};

struct pmcpl_ct_arc {
	struct pmcpl_ct_sample	pcta_samples;
	struct pmcpl_ct_sample	pcta_callid;
	unsigned		pcta_call;
	struct pmcpl_ct_node	*pcta_child;
};

struct pmcpl_ct_instr {
	uintfptr_t		pctf_func;
	struct pmcpl_ct_sample	pctf_samples;
};

/*
 * Each calltree node is tracked by a pmcpl_ct_node struct.
 */
struct pmcpl_ct_node {
#define PMCPL_PCT_TAG	0x00000001	/* Loop detection. */
	uint32_t		pct_flags;
	struct pmcstat_image	*pct_image;
	uintfptr_t		pct_func;
	struct pmcpl_ct_sample	pct_samples;

	int			pct_narc;
	int			pct_arc_c;
	struct pmcpl_ct_arc 	*pct_arc;

	/* TODO: optimize for large number of items. */
	int			pct_ninstr;
	int			pct_instr_c;
	struct pmcpl_ct_instr	*pct_instr;
};

struct pmcpl_ct_node_hash {
	struct pmcpl_ct_node  *pch_ctnode;
	LIST_ENTRY(pmcpl_ct_node_hash) pch_next;
};

struct pmcpl_ct_sample pmcpl_ct_callid;

#define PMCPL_CT_MAXCOL		PMC_CALLCHAIN_DEPTH_MAX	
#define PMCPL_CT_MAXLINE	1024	/* TODO: dynamic. */

struct pmcpl_ct_line {
	unsigned	ln_sum;
	unsigned	ln_index;
};

struct pmcpl_ct_line	pmcpl_ct_topmax[PMCPL_CT_MAXLINE+1];
struct pmcpl_ct_node	*pmcpl_ct_topscreen[PMCPL_CT_MAXCOL+1][PMCPL_CT_MAXLINE+1];

/*
 * All nodes indexed by function/image name are placed in a hash table.
 */
static LIST_HEAD(,pmcpl_ct_node_hash) pmcpl_ct_node_hash[PMCSTAT_NHASH];

/*
 * Root node for the graph.
 */
static struct pmcpl_ct_node *pmcpl_ct_root;

/*
 * Prototypes
 */

/*
 * Initialize a samples.
 */

static void
pmcpl_ct_samples_init(struct pmcpl_ct_sample *samples)
{

	samples->npmcs = 0;
	samples->sb = NULL;
}

/*
 * Free a samples.
 */

static void
pmcpl_ct_samples_free(struct pmcpl_ct_sample *samples)
{

	samples->npmcs = 0;
	free(samples->sb);
	samples->sb = NULL;
}

/*
 * Grow a sample block to store pmcstat_npmcs PMCs.
 */

static void
pmcpl_ct_samples_grow(struct pmcpl_ct_sample *samples)
{
	int npmcs;

	/* Enough storage. */
	if (pmcstat_npmcs <= samples->npmcs)
                return;

	npmcs = samples->npmcs +
	    max(pmcstat_npmcs - samples->npmcs, PMCPL_CT_GROWSIZE);
	samples->sb = realloc(samples->sb, npmcs * sizeof(unsigned));
	if (samples->sb == NULL)
		errx(EX_SOFTWARE, "ERROR: out of memory");
	bzero((char *)samples->sb + samples->npmcs * sizeof(unsigned),
	    (npmcs - samples->npmcs) * sizeof(unsigned));
	samples->npmcs = npmcs;
}

/*
 * Compute the sum of all root arcs.
 */

static void
pmcpl_ct_samples_root(struct pmcpl_ct_sample *samples)
{
	int i, pmcin;

	pmcpl_ct_samples_init(samples);
	pmcpl_ct_samples_grow(samples);

	for (i = 0; i < pmcpl_ct_root->pct_narc; i++)
		for (pmcin = 0; pmcin < pmcstat_npmcs; pmcin++)
			samples->sb[pmcin] += PMCPL_CT_SAMPLE(pmcin,
			    &pmcpl_ct_root->pct_arc[i].pcta_samples);
}

/*
 * Grow the arc table.
 */

static void
pmcpl_ct_arc_grow(int cursize, int *maxsize, struct pmcpl_ct_arc **items)
{
	int nmaxsize;

	if (cursize < *maxsize)
		return;

	nmaxsize = *maxsize + max(cursize + 1 - *maxsize, PMCPL_CT_GROWSIZE);
	*items = realloc(*items, nmaxsize * sizeof(struct pmcpl_ct_arc));
	if (*items == NULL)
		errx(EX_SOFTWARE, "ERROR: out of memory");
	bzero((char *)*items + *maxsize * sizeof(struct pmcpl_ct_arc),
	    (nmaxsize - *maxsize) * sizeof(struct pmcpl_ct_arc));
	*maxsize = nmaxsize;
}

/*
 * Grow the instr table.
 */

static void
pmcpl_ct_instr_grow(int cursize, int *maxsize, struct pmcpl_ct_instr **items)
{
	int nmaxsize;

	if (cursize < *maxsize)
		return;

	nmaxsize = *maxsize + max(cursize + 1 - *maxsize, PMCPL_CT_GROWSIZE);
	*items = realloc(*items, nmaxsize * sizeof(struct pmcpl_ct_instr));
	if (*items == NULL)
		errx(EX_SOFTWARE, "ERROR: out of memory");
	bzero((char *)*items + *maxsize * sizeof(struct pmcpl_ct_instr),
	    (nmaxsize - *maxsize) * sizeof(struct pmcpl_ct_instr));
	*maxsize = nmaxsize;
}

/*
 * Add a new instruction sample to given node.
 */

static void
pmcpl_ct_instr_add(struct pmcpl_ct_node *ct, int pmcin, uintfptr_t pc)
{
	int i;
	struct pmcpl_ct_instr *in;

	for (i = 0; i<ct->pct_ninstr; i++) {
		if (ct->pct_instr[i].pctf_func == pc) {
			in = &ct->pct_instr[i];
			pmcpl_ct_samples_grow(&in->pctf_samples);
			in->pctf_samples.sb[pmcin]++;
			return;
		}
	}

	pmcpl_ct_instr_grow(ct->pct_ninstr, &ct->pct_instr_c, &ct->pct_instr);
	in = &ct->pct_instr[ct->pct_ninstr];
	in->pctf_func = pc;
	pmcpl_ct_samples_init(&in->pctf_samples);
	pmcpl_ct_samples_grow(&in->pctf_samples);
	in->pctf_samples.sb[pmcin] = 1;
	ct->pct_ninstr++;
}

/*
 * Allocate a new node.
 */

static struct pmcpl_ct_node *
pmcpl_ct_node_allocate(struct pmcstat_image *image, uintfptr_t pc)
{
	struct pmcpl_ct_node *ct;

	if ((ct = malloc(sizeof(*ct))) == NULL)
		err(EX_OSERR, "ERROR: Cannot allocate callgraph node");

	ct->pct_flags	= 0;
	ct->pct_image 	= image;
	ct->pct_func	= pc;

	pmcpl_ct_samples_init(&ct->pct_samples);

	ct->pct_narc	= 0;
	ct->pct_arc_c	= 0;
	ct->pct_arc	= NULL;

	ct->pct_ninstr	= 0;
	ct->pct_instr_c	= 0;
	ct->pct_instr	= NULL;

	return (ct);
}

/*
 * Free a node.
 */

static void
pmcpl_ct_node_free(struct pmcpl_ct_node *ct)
{
	int i;

	for (i = 0; i < ct->pct_narc; i++) {
		pmcpl_ct_samples_free(&ct->pct_arc[i].pcta_samples);
		pmcpl_ct_samples_free(&ct->pct_arc[i].pcta_callid);
	}

	pmcpl_ct_samples_free(&ct->pct_samples);
	free(ct->pct_arc);
	free(ct->pct_instr);
	free(ct);
}

/*
 * Clear the graph tag on each node.
 */
static void
pmcpl_ct_node_cleartag(void)
{
	int i;
	struct pmcpl_ct_node_hash *pch;

	for (i = 0; i < PMCSTAT_NHASH; i++)
		LIST_FOREACH(pch, &pmcpl_ct_node_hash[i], pch_next)
			pch->pch_ctnode->pct_flags &= ~PMCPL_PCT_TAG;

	pmcpl_ct_root->pct_flags &= ~PMCPL_PCT_TAG;
}

/*
 * Print the callchain line by line with maximum cost at top.
 */ 

static int
pmcpl_ct_node_dumptop(int pmcin, struct pmcpl_ct_node *ct,
    struct pmcpl_ct_sample *rsamples, int x, int *y)
{
	int i, terminal;
	struct pmcpl_ct_arc *arc;

	if (ct->pct_flags & PMCPL_PCT_TAG)
		return 0;

	ct->pct_flags |= PMCPL_PCT_TAG;

	if (x >= PMCPL_CT_MAXCOL) {
		pmcpl_ct_topscreen[x][*y] = NULL;
		return 1;
	}
	pmcpl_ct_topscreen[x][*y] = ct;

	/*
	 * Check if this is a terminal node.
	 * We need to check that some samples exist
	 * for at least one arc for that PMC.
	 */
	terminal = 1;
	for (i = 0; i < ct->pct_narc; i++) {
		arc = &ct->pct_arc[i];
		if (PMCPL_CT_SAMPLE(pmcin,
		    &arc->pcta_samples) != 0 &&
		    PMCPL_CT_SAMPLEP(pmcin,
		    &arc->pcta_samples) > pmcstat_threshold &&
		    (arc->pcta_child->pct_flags & PMCPL_PCT_TAG) == 0) {
			terminal = 0;
			break;
		}
	}

	if (ct->pct_narc == 0 || terminal) {
		pmcpl_ct_topscreen[x+1][*y] = NULL;
		if (*y >= PMCPL_CT_MAXLINE)
			return 1;
		*y = *y + 1;
		for (i=0; i < x; i++)
			pmcpl_ct_topscreen[i][*y] =
			    pmcpl_ct_topscreen[i][*y - 1];
		return 0;
	}

	for (i = 0; i < ct->pct_narc; i++) {
		if (PMCPL_CT_SAMPLE(pmcin,
		    &ct->pct_arc[i].pcta_samples) == 0)
			continue;
		if (PMCPL_CT_SAMPLEP(pmcin,
		    &ct->pct_arc[i].pcta_samples) > pmcstat_threshold) {
			if (pmcpl_ct_node_dumptop(pmcin,
			        ct->pct_arc[i].pcta_child,
			        rsamples, x+1, y))
				return 1;
		}
	}

	return 0;
}

/*
 * Compare two top line by sum.
 */
static int
pmcpl_ct_line_compare(const void *a, const void *b)
{
	const struct pmcpl_ct_line *ct1, *ct2;

	ct1 = (const struct pmcpl_ct_line *) a;
	ct2 = (const struct pmcpl_ct_line *) b;

	/* Sort in reverse order */
	if (ct1->ln_sum < ct2->ln_sum)
		return (1);
	if (ct1->ln_sum > ct2->ln_sum)
		return (-1);
	return (0);
}

/*
 * Format and display given PMC index.
 */

static void
pmcpl_ct_node_printtop(struct pmcpl_ct_sample *rsamples, int pmcin, int maxy)
{
#undef	TS
#undef	TSI
#define	TS(x, y)	(pmcpl_ct_topscreen[x][y])
#define	TSI(x, y)	(pmcpl_ct_topscreen[x][pmcpl_ct_topmax[y].ln_index])

	int v_attrs, ns_len, vs_len, is_len, width, indentwidth, x, y;
	float v;
	char ns[30], vs[10], is[20];
	struct pmcpl_ct_node *ct;
	struct pmcstat_symbol *sym;
	const char *space = " ";

	/*
	 * Sort by line cost.
	 */
	for (y = 0; ; y++) {
		ct = TS(1, y);
		if (ct == NULL)
			break;

		pmcpl_ct_topmax[y].ln_sum = 0;
		pmcpl_ct_topmax[y].ln_index = y;
		for (x = 1; TS(x, y) != NULL; x++) {
			pmcpl_ct_topmax[y].ln_sum +=
			    PMCPL_CT_SAMPLE(pmcin, &TS(x, y)->pct_samples);
		}
	}
	qsort(pmcpl_ct_topmax, y, sizeof(pmcpl_ct_topmax[0]),
	    pmcpl_ct_line_compare);
	pmcpl_ct_topmax[y].ln_index = y;

	for (y = 0; y < maxy; y++) {
		ct = TSI(1, y);
		if (ct == NULL)
			break;

		if (y > 0)
			PMCSTAT_PRINTW("\n");

		/* Output sum. */
		v = pmcpl_ct_topmax[y].ln_sum * 100.0 /
		    rsamples->sb[pmcin];
		snprintf(vs, sizeof(vs), "%.1f", v);
		v_attrs = PMCSTAT_ATTRPERCENT(v);
		PMCSTAT_ATTRON(v_attrs);
		PMCSTAT_PRINTW("%5.5s ", vs);
		PMCSTAT_ATTROFF(v_attrs);

		width = indentwidth = 5 + 1;

		for (x = 1; (ct = TSI(x, y)) != NULL; x++) {

			vs[0] = '\0'; vs_len = 0;
			is[0] = '\0'; is_len = 0;

			/* Format value. */
			v = PMCPL_CT_SAMPLEP(pmcin, &ct->pct_samples);
			if (v > pmcstat_threshold)
				vs_len  = snprintf(vs, sizeof(vs),
				    "(%.1f%%)", v);
			v_attrs = PMCSTAT_ATTRPERCENT(v);

			if (pmcstat_skiplink && v <= pmcstat_threshold) {
				strlcpy(ns, ".", sizeof(ns));
				ns_len = 1;
			} else {
			sym = pmcstat_symbol_search(ct->pct_image, ct->pct_func);
			if (sym != NULL) {
				ns_len = snprintf(ns, sizeof(ns), "%s",
				    pmcstat_string_unintern(sym->ps_name));
			} else
				ns_len = snprintf(ns, sizeof(ns), "%p",
				    (void *)ct->pct_func);

			/* Format image. */
			if (x == 1 ||
			    TSI(x-1, y)->pct_image != ct->pct_image)
				is_len = snprintf(is, sizeof(is), "@%s",
				    pmcstat_string_unintern(ct->pct_image->pi_name));

			/* Check for line wrap. */
			width += ns_len + is_len + vs_len + 1;
			}
			if (width >= pmcstat_displaywidth) {
				maxy--;
				if (y >= maxy)
					break;
				PMCSTAT_PRINTW("\n%*s", indentwidth, space);
				width = indentwidth + ns_len + is_len + vs_len;
			}

			PMCSTAT_ATTRON(v_attrs);
			PMCSTAT_PRINTW("%s%s%s ", ns, is, vs);
			PMCSTAT_ATTROFF(v_attrs);
		}
	}
}

/*
 * Output top mode snapshot.
 */

void
pmcpl_ct_topdisplay(void)
{
	int y;
	struct pmcpl_ct_sample r, *rsamples;

	rsamples = &r;
	pmcpl_ct_samples_root(rsamples);

	pmcpl_ct_node_cleartag();

	PMCSTAT_PRINTW("%5.5s %s\n", "%SAMP", "CALLTREE");

	y = 0;
	if (pmcpl_ct_node_dumptop(pmcstat_pmcinfilter,
	    pmcpl_ct_root, rsamples, 0, &y))
		PMCSTAT_PRINTW("...\n");
	pmcpl_ct_topscreen[1][y] = NULL;

	pmcpl_ct_node_printtop(rsamples,
	    pmcstat_pmcinfilter, pmcstat_displayheight - 2);

	pmcpl_ct_samples_free(rsamples);
}

/*
 * Handle top mode keypress.
 */

int
pmcpl_ct_topkeypress(int c, WINDOW *w)
{

	switch (c) {
	case 'f':
		pmcstat_skiplink = !pmcstat_skiplink;
		wprintw(w, "skip empty link %s", pmcstat_skiplink ? "on" : "off");
		break;
	}

	return 0;
}

/*
 * Look for a callgraph node associated with pmc `pmcid' in the global
 * hash table that corresponds to the given `pc' value in the process map
 * `ppm'.
 */

static struct pmcpl_ct_node *
pmcpl_ct_node_hash_lookup_pc(struct pmcpl_ct_node *parent,
    struct pmcstat_pcmap *ppm, uintfptr_t pc, int pmcin)
{
	struct pmcstat_symbol *sym;
	struct pmcstat_image *image;
	struct pmcpl_ct_node *ct;
	struct pmcpl_ct_node_hash *h;
	struct pmcpl_ct_arc *arc;
	uintfptr_t loadaddress;
	int i;
	unsigned int hash;

	assert(parent != NULL);

	image = ppm->ppm_image;

	loadaddress = ppm->ppm_lowpc + image->pi_vaddr - image->pi_start;
	pc -= loadaddress;	/* Convert to an offset in the image. */

	/*
	 * Try determine the function at this offset.  If we can't
	 * find a function round leave the `pc' value alone.
	 */
	if ((sym = pmcstat_symbol_search(image, pc)) != NULL)
		pc = sym->ps_start;
	else
		pmcstat_stats.ps_samples_unknown_function++;

	for (hash = i = 0; i < (int)sizeof(uintfptr_t); i++)
		hash += (pc >> i) & 0xFF;

	hash &= PMCSTAT_HASH_MASK;

	ct = NULL;
	LIST_FOREACH(h, &pmcpl_ct_node_hash[hash], pch_next) {
		ct = h->pch_ctnode;

		assert(ct != NULL);

		if (ct->pct_image == image && ct->pct_func == pc) {
			/*
			 * Find related arc in parent node and
			 * increment the sample count.
			 */
			for (i = 0; i < parent->pct_narc; i++) {
				if (parent->pct_arc[i].pcta_child == ct) {
					arc = &parent->pct_arc[i];
					pmcpl_ct_samples_grow(&arc->pcta_samples);
					arc->pcta_samples.sb[pmcin]++;
					/* Estimate call count. */
					pmcpl_ct_samples_grow(&arc->pcta_callid);
					if (pmcpl_ct_callid.sb[pmcin] -
					    arc->pcta_callid.sb[pmcin] > 1)
						arc->pcta_call++;
					arc->pcta_callid.sb[pmcin] =
					    pmcpl_ct_callid.sb[pmcin];
					return (ct);
				}
			}

			/*
			 * No arc found for us, add ourself to the parent.
			 */
			pmcpl_ct_arc_grow(parent->pct_narc,
			    &parent->pct_arc_c, &parent->pct_arc);
			arc = &parent->pct_arc[parent->pct_narc];
			pmcpl_ct_samples_grow(&arc->pcta_samples);
			arc->pcta_samples.sb[pmcin] = 1;
			arc->pcta_call = 1;
			pmcpl_ct_samples_grow(&arc->pcta_callid);
			arc->pcta_callid.sb[pmcin] = pmcpl_ct_callid.sb[pmcin];
			arc->pcta_child = ct;
			parent->pct_narc++;
			return (ct);
		}
	}

	/*
	 * We haven't seen this (pmcid, pc) tuple yet, so allocate a
	 * new callgraph node and a new hash table entry for it.
	 */
	ct = pmcpl_ct_node_allocate(image, pc);
	if ((h = malloc(sizeof(*h))) == NULL)
		err(EX_OSERR, "ERROR: Could not allocate callgraph node");

	h->pch_ctnode = ct;
	LIST_INSERT_HEAD(&pmcpl_ct_node_hash[hash], h, pch_next);

	pmcpl_ct_arc_grow(parent->pct_narc,
	    &parent->pct_arc_c, &parent->pct_arc);
	arc = &parent->pct_arc[parent->pct_narc];
	pmcpl_ct_samples_grow(&arc->pcta_samples);
	arc->pcta_samples.sb[pmcin] = 1;
	arc->pcta_call = 1;
	pmcpl_ct_samples_grow(&arc->pcta_callid);
	arc->pcta_callid.sb[pmcin] = pmcpl_ct_callid.sb[pmcin];
	arc->pcta_child = ct;
	parent->pct_narc++;
	return (ct);
}

/*
 * Record a callchain.
 */

void
pmcpl_ct_process(struct pmcstat_process *pp, struct pmcstat_pmcrecord *pmcr,
    uint32_t nsamples, uintfptr_t *cc, int usermode, uint32_t cpu)
{
	int n, pmcin;
	struct pmcstat_pcmap *ppm[PMC_CALLCHAIN_DEPTH_MAX];
	struct pmcstat_process *km;
	struct pmcpl_ct_node *parent, *child;

	(void) cpu;

	assert(nsamples>0 && nsamples<=PMC_CALLCHAIN_DEPTH_MAX);

	/* Get the PMC index. */
	pmcin = pmcr->pr_pmcin;

	/*
	 * Validate mapping for the callchain.
	 * Go from bottom to first invalid entry.
	 */
	km = pmcstat_kernproc;
	for (n = 0; n < (int)nsamples; n++) {
		ppm[n] = pmcstat_process_find_map(usermode ?
		    pp : km, cc[n]);
		if (ppm[n] == NULL) {
			/* Detect full frame capture (kernel + user). */
			if (!usermode) {
				ppm[n] = pmcstat_process_find_map(pp, cc[n]);
				if (ppm[n] != NULL)
					km = pp;
			}
		}
		if (ppm[n] == NULL)
			break;
	}
	if (n-- == 0) {
		pmcstat_stats.ps_callchain_dubious_frames++;
		pmcr->pr_dubious_frames++;
		return;
	}

	/* Increase the call generation counter. */
	pmcpl_ct_samples_grow(&pmcpl_ct_callid);
	pmcpl_ct_callid.sb[pmcin]++;

	/*
	 * Iterate remaining addresses.
	 */
	for (parent = pmcpl_ct_root, child = NULL; n >= 0; n--) {
		child = pmcpl_ct_node_hash_lookup_pc(parent, ppm[n], cc[n],
		    pmcin);
		if (child == NULL) {
			pmcstat_stats.ps_callchain_dubious_frames++;
			continue;
		}
		parent = child;
	}

	/*
	 * Increment the sample count for this PMC.
	 */
	if (child != NULL) {
		pmcpl_ct_samples_grow(&child->pct_samples);
		child->pct_samples.sb[pmcin]++;

		/* Update per instruction sample if required. */
		if (args.pa_ctdumpinstr)
			pmcpl_ct_instr_add(child, pmcin, cc[0] -
			    (ppm[0]->ppm_lowpc + ppm[0]->ppm_image->pi_vaddr -
			     ppm[0]->ppm_image->pi_start));
	}
}

/*
 * Print node self cost.
 */

static void
pmcpl_ct_node_printself(struct pmcpl_ct_node *ct)
{
	int i, j, line;
	uintptr_t addr;
	struct pmcstat_symbol *sym;
	char sourcefile[PATH_MAX];
	char funcname[PATH_MAX];

	/*
	 * Object binary.
	 */
#ifdef PMCPL_CT_OPTIMIZEFN
	if (pmcpl_ct_prevfn != ct->pct_image->pi_fullpath) {
#endif
		pmcpl_ct_prevfn = ct->pct_image->pi_fullpath;
		fprintf(args.pa_graphfile, "ob=%s\n",
		    pmcstat_string_unintern(pmcpl_ct_prevfn));
#ifdef PMCPL_CT_OPTIMIZEFN
	}
#endif

	/*
	 * Function name.
	 */
	if (pmcstat_image_addr2line(ct->pct_image, ct->pct_func,
	    sourcefile, sizeof(sourcefile), &line,
	    funcname, sizeof(funcname))) {
		fprintf(args.pa_graphfile, "fn=%s\n",
		    funcname);
	} else {
		sym = pmcstat_symbol_search(ct->pct_image, ct->pct_func);
		if (sym != NULL)
			fprintf(args.pa_graphfile, "fn=%s\n",
			    pmcstat_string_unintern(sym->ps_name));
		else
			fprintf(args.pa_graphfile, "fn=%p\n",
			    (void *)(ct->pct_image->pi_vaddr + ct->pct_func));
	}

	/*
	 * Self cost.
	 */
	if (ct->pct_ninstr > 0) {
		for (i = 0; i < ct->pct_ninstr; i++) {
			addr = ct->pct_image->pi_vaddr +
			    ct->pct_instr[i].pctf_func;
			line = 0;
			if (pmcstat_image_addr2line(ct->pct_image, addr,
			    sourcefile, sizeof(sourcefile), &line,
			    funcname, sizeof(funcname)))
				fprintf(args.pa_graphfile, "fl=%s\n", sourcefile);
			fprintf(args.pa_graphfile, "%p %u", (void *)addr, line);
			for (j = 0; j<pmcstat_npmcs; j++)
				fprintf(args.pa_graphfile, " %u",
				    PMCPL_CT_SAMPLE(j,
				    &ct->pct_instr[i].pctf_samples));
			fprintf(args.pa_graphfile, "\n");
		}
	} else {
		addr = ct->pct_image->pi_vaddr + ct->pct_func;
		line = 0;
		if (pmcstat_image_addr2line(ct->pct_image, addr,
		    sourcefile, sizeof(sourcefile), &line,
		    funcname, sizeof(funcname)))
			fprintf(args.pa_graphfile, "fl=%s\n", sourcefile);
		fprintf(args.pa_graphfile, "* *");
		for (i = 0; i<pmcstat_npmcs ; i++)
			fprintf(args.pa_graphfile, " %u",
			    PMCPL_CT_SAMPLE(i, &ct->pct_samples));
		fprintf(args.pa_graphfile, "\n");
	}
}

/*
 * Print node child cost.
 */

static void
pmcpl_ct_node_printchild(struct pmcpl_ct_node *ct)
{
	int i, j, line;
	uintptr_t addr;
	struct pmcstat_symbol *sym;
	struct pmcpl_ct_node *child;
	char sourcefile[PATH_MAX];
	char funcname[PATH_MAX];

	/*
	 * Child cost.
	 * TODO: attach child cost to the real position in the funtion.
	 * TODO: cfn=<fn> / call <ncall> addr(<fn>) / addr(call <fn>) <arccost>
	 */
	for (i=0 ; i<ct->pct_narc; i++) {
		child = ct->pct_arc[i].pcta_child;

		/* Object binary. */
#ifdef PMCPL_CT_OPTIMIZEFN
		if (pmcpl_ct_prevfn != child->pct_image->pi_fullpath) {
#endif
			pmcpl_ct_prevfn = child->pct_image->pi_fullpath;
			fprintf(args.pa_graphfile, "cob=%s\n",
			    pmcstat_string_unintern(pmcpl_ct_prevfn));
#if PMCPL_CT_OPTIMIZEFN
		}
#endif
		/* Child function name. */
		addr = child->pct_image->pi_vaddr + child->pct_func;
		/* Child function source file. */
		if (pmcstat_image_addr2line(child->pct_image, addr,
		    sourcefile, sizeof(sourcefile), &line,
		    funcname, sizeof(funcname))) {
			fprintf(args.pa_graphfile, "cfn=%s\n", funcname);
			fprintf(args.pa_graphfile, "cfl=%s\n", sourcefile);
		} else {
			sym = pmcstat_symbol_search(child->pct_image,
			    child->pct_func);
			if (sym != NULL)
				fprintf(args.pa_graphfile, "cfn=%s\n",
				    pmcstat_string_unintern(sym->ps_name));
			else
				fprintf(args.pa_graphfile, "cfn=%p\n", (void *)addr);
		}

		/* Child function address, line and call count. */
		fprintf(args.pa_graphfile, "calls=%u %p %u\n",
		    ct->pct_arc[i].pcta_call, (void *)addr, line);

		if (ct->pct_image != NULL) {
			/* Call address, line, sample. */
			addr = ct->pct_image->pi_vaddr + ct->pct_func;
			line = 0;
			if (pmcstat_image_addr2line(ct->pct_image, addr, sourcefile,
			    sizeof(sourcefile), &line,
			    funcname, sizeof(funcname)))
				fprintf(args.pa_graphfile, "%p %u", (void *)addr, line);
			else
				fprintf(args.pa_graphfile, "* *");
		}
		else
			fprintf(args.pa_graphfile, "* *");
		for (j = 0; j<pmcstat_npmcs; j++)
			fprintf(args.pa_graphfile, " %u",
			    PMCPL_CT_SAMPLE(j, &ct->pct_arc[i].pcta_samples));
		fprintf(args.pa_graphfile, "\n");
	}
}

/*
 * Clean the PMC name for Kcachegrind formula
 */

static void
pmcpl_ct_fixup_pmcname(char *s)
{
	char *p;

	for (p = s; *p; p++)
		if (!isalnum(*p))
			*p = '_';
}

/*
 * Print a calltree (KCachegrind) for all PMCs.
 */

static void
pmcpl_ct_print(void)
{
	int n, i;
	struct pmcpl_ct_node_hash *pch;
	struct pmcpl_ct_sample rsamples;
	char name[40];

	pmcpl_ct_samples_root(&rsamples);
	pmcpl_ct_prevfn = NULL;

	fprintf(args.pa_graphfile,
		"version: 1\n"
		"creator: pmcstat\n"
		"positions: instr line\n"
		"events:");
	for (i=0; i<pmcstat_npmcs; i++) {
		snprintf(name, sizeof(name), "%s_%d",
		    pmcstat_pmcindex_to_name(i), i);
		pmcpl_ct_fixup_pmcname(name);
		fprintf(args.pa_graphfile, " %s", name);
	}
	fprintf(args.pa_graphfile, "\nsummary:");
	for (i=0; i<pmcstat_npmcs ; i++)
		fprintf(args.pa_graphfile, " %u",
		    PMCPL_CT_SAMPLE(i, &rsamples));
	fprintf(args.pa_graphfile, "\n\n");

	/*
	 * Fake root node
	 */
	fprintf(args.pa_graphfile, "ob=FreeBSD\n");
	fprintf(args.pa_graphfile, "fn=ROOT\n");
	fprintf(args.pa_graphfile, "* *");
	for (i = 0; i<pmcstat_npmcs ; i++)
		fprintf(args.pa_graphfile, " 0");
	fprintf(args.pa_graphfile, "\n");
	pmcpl_ct_node_printchild(pmcpl_ct_root);

	for (n = 0; n < PMCSTAT_NHASH; n++)
		LIST_FOREACH(pch, &pmcpl_ct_node_hash[n], pch_next) {
			pmcpl_ct_node_printself(pch->pch_ctnode);
			pmcpl_ct_node_printchild(pch->pch_ctnode);
	}

	pmcpl_ct_samples_free(&rsamples);
}

int
pmcpl_ct_configure(char *opt)
{

	if (strncmp(opt, "skiplink=", 9) == 0) {
		pmcstat_skiplink = atoi(opt+9);
	} else
		return (0);

	return (1);
}

int
pmcpl_ct_init(void)
{
	int i;

	pmcpl_ct_prevfn = NULL;
	pmcpl_ct_root = pmcpl_ct_node_allocate(NULL, 0);

	for (i = 0; i < PMCSTAT_NHASH; i++)
		LIST_INIT(&pmcpl_ct_node_hash[i]);

	pmcpl_ct_samples_init(&pmcpl_ct_callid);

	return (0);
}

void
pmcpl_ct_shutdown(FILE *mf)
{
	int i;
	struct pmcpl_ct_node_hash *pch, *pchtmp;

	(void) mf;

	if (args.pa_flags & FLAG_DO_CALLGRAPHS)
		pmcpl_ct_print();

	/*
	 * Free memory.
	 */

	for (i = 0; i < PMCSTAT_NHASH; i++) {
		LIST_FOREACH_SAFE(pch, &pmcpl_ct_node_hash[i], pch_next,
		    pchtmp) {
			pmcpl_ct_node_free(pch->pch_ctnode);
			free(pch);
		}
	}

	pmcpl_ct_node_free(pmcpl_ct_root);
	pmcpl_ct_root = NULL;

	pmcpl_ct_samples_free(&pmcpl_ct_callid);
}