freebsd-skq/lib/libpmcstat/libpmcstat_logging.c
Ruslan Bukin d27927f731 Extract a set of pmcstat functions and interfaces to the new internal
library -- libpmcstat.

This includes PMC logging module, symbols lookup functions,
ELF parsing, process management, PMC attachment, etc.

This allows to reuse code while building new hwpmc(4)-based applications.

Also add pmcstat_symbol_search_by_name() function that allows to find
mapped IP range for a given function name.

Reviewed by:	kib
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D12718
2017-10-24 16:28:00 +00:00

719 lines
19 KiB
C

/*-
* Copyright (c) 2003-2008 Joseph Koshy
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/cpuset.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/pmc.h>
#include <assert.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <netdb.h>
#include <pmc.h>
#include <pmclog.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <sysexits.h>
#include <unistd.h>
#include "libpmcstat.h"
/*
* Get PMC record by id, apply merge policy.
*/
static struct pmcstat_pmcrecord *
pmcstat_lookup_pmcid(pmc_id_t pmcid, int pmcstat_mergepmc)
{
struct pmcstat_pmcrecord *pr;
LIST_FOREACH(pr, &pmcstat_pmcs, pr_next) {
if (pr->pr_pmcid == pmcid) {
if (pmcstat_mergepmc)
return pr->pr_merge;
return pr;
}
}
return NULL;
}
/*
* Add a {pmcid,name} mapping.
*/
static void
pmcstat_pmcid_add(pmc_id_t pmcid, pmcstat_interned_string ps,
struct pmcstat_args *args, struct pmc_plugins *plugins,
int *pmcstat_npmcs)
{
struct pmcstat_pmcrecord *pr, *prm;
/* Replace an existing name for the PMC. */
prm = NULL;
LIST_FOREACH(pr, &pmcstat_pmcs, pr_next)
if (pr->pr_pmcid == pmcid) {
pr->pr_pmcname = ps;
return;
} else if (pr->pr_pmcname == ps)
prm = pr;
/*
* Otherwise, allocate a new descriptor and call the
* plugins hook.
*/
if ((pr = malloc(sizeof(*pr))) == NULL)
err(EX_OSERR, "ERROR: Cannot allocate pmc record");
pr->pr_pmcid = pmcid;
pr->pr_pmcname = ps;
pr->pr_pmcin = *pmcstat_npmcs++;
pr->pr_samples = 0;
pr->pr_dubious_frames = 0;
pr->pr_merge = prm == NULL ? pr : prm;
LIST_INSERT_HEAD(&pmcstat_pmcs, pr, pr_next);
if (plugins[args->pa_pplugin].pl_newpmc != NULL)
plugins[args->pa_pplugin].pl_newpmc(ps, pr);
if (plugins[args->pa_plugin].pl_newpmc != NULL)
plugins[args->pa_plugin].pl_newpmc(ps, pr);
}
/*
* Unmap images in the range [start..end) associated with process
* 'pp'.
*/
static void
pmcstat_image_unmap(struct pmcstat_process *pp, uintfptr_t start,
uintfptr_t end)
{
struct pmcstat_pcmap *pcm, *pcmtmp, *pcmnew;
assert(pp != NULL);
assert(start < end);
/*
* Cases:
* - we could have the range completely in the middle of an
* existing pcmap; in this case we have to split the pcmap
* structure into two (i.e., generate a 'hole').
* - we could have the range covering multiple pcmaps; these
* will have to be removed.
* - we could have either 'start' or 'end' falling in the
* middle of a pcmap; in this case shorten the entry.
*/
TAILQ_FOREACH_SAFE(pcm, &pp->pp_map, ppm_next, pcmtmp) {
assert(pcm->ppm_lowpc < pcm->ppm_highpc);
if (pcm->ppm_highpc <= start)
continue;
if (pcm->ppm_lowpc >= end)
return;
if (pcm->ppm_lowpc >= start && pcm->ppm_highpc <= end) {
/*
* The current pcmap is completely inside the
* unmapped range: remove it entirely.
*/
TAILQ_REMOVE(&pp->pp_map, pcm, ppm_next);
free(pcm);
} else if (pcm->ppm_lowpc < start && pcm->ppm_highpc > end) {
/*
* Split this pcmap into two; curtail the
* current map to end at [start-1], and start
* the new one at [end].
*/
if ((pcmnew = malloc(sizeof(*pcmnew))) == NULL)
err(EX_OSERR,
"ERROR: Cannot split a map entry");
pcmnew->ppm_image = pcm->ppm_image;
pcmnew->ppm_lowpc = end;
pcmnew->ppm_highpc = pcm->ppm_highpc;
pcm->ppm_highpc = start;
TAILQ_INSERT_AFTER(&pp->pp_map, pcm, pcmnew, ppm_next);
return;
} else if (pcm->ppm_lowpc < start && pcm->ppm_highpc <= end)
pcm->ppm_highpc = start;
else if (pcm->ppm_lowpc >= start && pcm->ppm_highpc > end)
pcm->ppm_lowpc = end;
else
assert(0);
}
}
/*
* Convert a hwpmc(4) log to profile information. A system-wide
* callgraph is generated if FLAG_DO_CALLGRAPHS is set. gmon.out
* files usable by gprof(1) are created if FLAG_DO_GPROF is set.
*/
int
pmcstat_analyze_log(struct pmcstat_args *args,
struct pmc_plugins *plugins,
struct pmcstat_stats *pmcstat_stats,
struct pmcstat_process *pmcstat_kernproc,
int pmcstat_mergepmc,
int *pmcstat_npmcs,
int *ps_samples_period)
{
uint32_t cpu, cpuflags;
uintfptr_t pc;
pid_t pid;
struct pmcstat_image *image;
struct pmcstat_process *pp, *ppnew;
struct pmcstat_pcmap *ppm, *ppmtmp;
struct pmclog_ev ev;
struct pmcstat_pmcrecord *pmcr;
pmcstat_interned_string image_path;
assert(args->pa_flags & FLAG_DO_ANALYSIS);
if (elf_version(EV_CURRENT) == EV_NONE)
err(EX_UNAVAILABLE, "Elf library initialization failed");
while (pmclog_read(args->pa_logparser, &ev) == 0) {
assert(ev.pl_state == PMCLOG_OK);
switch (ev.pl_type) {
case PMCLOG_TYPE_INITIALIZE:
if ((ev.pl_u.pl_i.pl_version & 0xFF000000) !=
PMC_VERSION_MAJOR << 24 && args->pa_verbosity > 0)
warnx(
"WARNING: Log version 0x%x does not match compiled version 0x%x.",
ev.pl_u.pl_i.pl_version, PMC_VERSION_MAJOR);
break;
case PMCLOG_TYPE_MAP_IN:
/*
* Introduce an address range mapping for a
* userland process or the kernel (pid == -1).
*
* We always allocate a process descriptor so
* that subsequent samples seen for this
* address range are mapped to the current
* object being mapped in.
*/
pid = ev.pl_u.pl_mi.pl_pid;
if (pid == -1)
pp = pmcstat_kernproc;
else
pp = pmcstat_process_lookup(pid,
PMCSTAT_ALLOCATE);
assert(pp != NULL);
image_path = pmcstat_string_intern(ev.pl_u.pl_mi.
pl_pathname);
image = pmcstat_image_from_path(image_path, pid == -1,
args, plugins);
if (image->pi_type == PMCSTAT_IMAGE_UNKNOWN)
pmcstat_image_determine_type(image, args);
if (image->pi_type != PMCSTAT_IMAGE_INDETERMINABLE)
pmcstat_image_link(pp, image,
ev.pl_u.pl_mi.pl_start);
break;
case PMCLOG_TYPE_MAP_OUT:
/*
* Remove an address map.
*/
pid = ev.pl_u.pl_mo.pl_pid;
if (pid == -1)
pp = pmcstat_kernproc;
else
pp = pmcstat_process_lookup(pid, 0);
if (pp == NULL) /* unknown process */
break;
pmcstat_image_unmap(pp, ev.pl_u.pl_mo.pl_start,
ev.pl_u.pl_mo.pl_end);
break;
case PMCLOG_TYPE_PCSAMPLE:
/*
* Note: the `PCSAMPLE' log entry is not
* generated by hpwmc(4) after version 2.
*/
/*
* We bring in the gmon file for the image
* currently associated with the PMC & pid
* pair and increment the appropriate entry
* bin inside this.
*/
pmcstat_stats->ps_samples_total++;
*ps_samples_period += 1;
pc = ev.pl_u.pl_s.pl_pc;
pp = pmcstat_process_lookup(ev.pl_u.pl_s.pl_pid,
PMCSTAT_ALLOCATE);
/* Get PMC record. */
pmcr = pmcstat_lookup_pmcid(ev.pl_u.pl_s.pl_pmcid, pmcstat_mergepmc);
assert(pmcr != NULL);
pmcr->pr_samples++;
/*
* Call the plugins processing
* TODO: move pmcstat_process_find_map inside plugins
*/
if (plugins[args->pa_pplugin].pl_process != NULL)
plugins[args->pa_pplugin].pl_process(
pp, pmcr, 1, &pc,
pmcstat_process_find_map(pp, pc) != NULL, 0);
plugins[args->pa_plugin].pl_process(
pp, pmcr, 1, &pc,
pmcstat_process_find_map(pp, pc) != NULL, 0);
break;
case PMCLOG_TYPE_CALLCHAIN:
pmcstat_stats->ps_samples_total++;
*ps_samples_period += 1;
cpuflags = ev.pl_u.pl_cc.pl_cpuflags;
cpu = PMC_CALLCHAIN_CPUFLAGS_TO_CPU(cpuflags);
/* Filter on the CPU id. */
if (!CPU_ISSET(cpu, &(args->pa_cpumask))) {
pmcstat_stats->ps_samples_skipped++;
break;
}
pp = pmcstat_process_lookup(ev.pl_u.pl_cc.pl_pid,
PMCSTAT_ALLOCATE);
/* Get PMC record. */
pmcr = pmcstat_lookup_pmcid(ev.pl_u.pl_cc.pl_pmcid, pmcstat_mergepmc);
assert(pmcr != NULL);
pmcr->pr_samples++;
/*
* Call the plugins processing
*/
if (plugins[args->pa_pplugin].pl_process != NULL)
plugins[args->pa_pplugin].pl_process(
pp, pmcr,
ev.pl_u.pl_cc.pl_npc,
ev.pl_u.pl_cc.pl_pc,
PMC_CALLCHAIN_CPUFLAGS_TO_USERMODE(cpuflags),
cpu);
plugins[args->pa_plugin].pl_process(
pp, pmcr,
ev.pl_u.pl_cc.pl_npc,
ev.pl_u.pl_cc.pl_pc,
PMC_CALLCHAIN_CPUFLAGS_TO_USERMODE(cpuflags),
cpu);
break;
case PMCLOG_TYPE_PMCALLOCATE:
/*
* Record the association pmc id between this
* PMC and its name.
*/
pmcstat_pmcid_add(ev.pl_u.pl_a.pl_pmcid,
pmcstat_string_intern(ev.pl_u.pl_a.pl_evname),
args, plugins, pmcstat_npmcs);
break;
case PMCLOG_TYPE_PMCALLOCATEDYN:
/*
* Record the association pmc id between this
* PMC and its name.
*/
pmcstat_pmcid_add(ev.pl_u.pl_ad.pl_pmcid,
pmcstat_string_intern(ev.pl_u.pl_ad.pl_evname),
args, plugins, pmcstat_npmcs);
break;
case PMCLOG_TYPE_PROCEXEC:
/*
* Change the executable image associated with
* a process.
*/
pp = pmcstat_process_lookup(ev.pl_u.pl_x.pl_pid,
PMCSTAT_ALLOCATE);
/* delete the current process map */
TAILQ_FOREACH_SAFE(ppm, &pp->pp_map, ppm_next, ppmtmp) {
TAILQ_REMOVE(&pp->pp_map, ppm, ppm_next);
free(ppm);
}
/*
* Associate this process image.
*/
image_path = pmcstat_string_intern(
ev.pl_u.pl_x.pl_pathname);
assert(image_path != NULL);
pmcstat_process_exec(pp, image_path,
ev.pl_u.pl_x.pl_entryaddr, args,
plugins, pmcstat_stats);
break;
case PMCLOG_TYPE_PROCEXIT:
/*
* Due to the way the log is generated, the
* last few samples corresponding to a process
* may appear in the log after the process
* exit event is recorded. Thus we keep the
* process' descriptor and associated data
* structures around, but mark the process as
* having exited.
*/
pp = pmcstat_process_lookup(ev.pl_u.pl_e.pl_pid, 0);
if (pp == NULL)
break;
pp->pp_isactive = 0; /* mark as a zombie */
break;
case PMCLOG_TYPE_SYSEXIT:
pp = pmcstat_process_lookup(ev.pl_u.pl_se.pl_pid, 0);
if (pp == NULL)
break;
pp->pp_isactive = 0; /* make a zombie */
break;
case PMCLOG_TYPE_PROCFORK:
/*
* Allocate a process descriptor for the new
* (child) process.
*/
ppnew =
pmcstat_process_lookup(ev.pl_u.pl_f.pl_newpid,
PMCSTAT_ALLOCATE);
/*
* If we had been tracking the parent, clone
* its address maps.
*/
pp = pmcstat_process_lookup(ev.pl_u.pl_f.pl_oldpid, 0);
if (pp == NULL)
break;
TAILQ_FOREACH(ppm, &pp->pp_map, ppm_next)
pmcstat_image_link(ppnew, ppm->ppm_image,
ppm->ppm_lowpc);
break;
default: /* other types of entries are not relevant */
break;
}
}
if (ev.pl_state == PMCLOG_EOF)
return (PMCSTAT_FINISHED);
else if (ev.pl_state == PMCLOG_REQUIRE_DATA)
return (PMCSTAT_RUNNING);
err(EX_DATAERR,
"ERROR: event parsing failed (record %jd, offset 0x%jx)",
(uintmax_t) ev.pl_count + 1, ev.pl_offset);
}
/*
* Open a log file, for reading or writing.
*
* The function returns the fd of a successfully opened log or -1 in
* case of failure.
*/
int
pmcstat_open_log(const char *path, int mode)
{
int error, fd, cfd;
size_t hlen;
const char *p, *errstr;
struct addrinfo hints, *res, *res0;
char hostname[MAXHOSTNAMELEN];
errstr = NULL;
fd = -1;
/*
* If 'path' is "-" then open one of stdin or stdout depending
* on the value of 'mode'.
*
* If 'path' contains a ':' and does not start with a '/' or '.',
* and is being opened for writing, treat it as a "host:port"
* specification and open a network socket.
*
* Otherwise, treat 'path' as a file name and open that.
*/
if (path[0] == '-' && path[1] == '\0')
fd = (mode == PMCSTAT_OPEN_FOR_READ) ? 0 : 1;
else if (path[0] != '/' &&
path[0] != '.' && strchr(path, ':') != NULL) {
p = strrchr(path, ':');
hlen = p - path;
if (p == path || hlen >= sizeof(hostname)) {
errstr = strerror(EINVAL);
goto done;
}
assert(hlen < sizeof(hostname));
(void) strncpy(hostname, path, hlen);
hostname[hlen] = '\0';
(void) memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
if ((error = getaddrinfo(hostname, p+1, &hints, &res0)) != 0) {
errstr = gai_strerror(error);
goto done;
}
fd = -1;
for (res = res0; res; res = res->ai_next) {
if ((fd = socket(res->ai_family, res->ai_socktype,
res->ai_protocol)) < 0) {
errstr = strerror(errno);
continue;
}
if (mode == PMCSTAT_OPEN_FOR_READ) {
if (bind(fd, res->ai_addr, res->ai_addrlen) < 0) {
errstr = strerror(errno);
(void) close(fd);
fd = -1;
continue;
}
listen(fd, 1);
cfd = accept(fd, NULL, NULL);
(void) close(fd);
if (cfd < 0) {
errstr = strerror(errno);
fd = -1;
break;
}
fd = cfd;
} else {
if (connect(fd, res->ai_addr, res->ai_addrlen) < 0) {
errstr = strerror(errno);
(void) close(fd);
fd = -1;
continue;
}
}
errstr = NULL;
break;
}
freeaddrinfo(res0);
} else if ((fd = open(path, mode == PMCSTAT_OPEN_FOR_READ ?
O_RDONLY : (O_WRONLY|O_CREAT|O_TRUNC),
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)) < 0)
errstr = strerror(errno);
done:
if (errstr)
errx(EX_OSERR, "ERROR: Cannot open \"%s\" for %s: %s.", path,
(mode == PMCSTAT_OPEN_FOR_READ ? "reading" : "writing"),
errstr);
return (fd);
}
/*
* Close a logfile, after first flushing all in-module queued data.
*/
int
pmcstat_close_log(struct pmcstat_args *args)
{
/* If a local logfile is configured ask the kernel to stop
* and flush data. Kernel will close the file when data is flushed
* so keep the status to EXITING.
*/
if (args->pa_logfd != -1) {
if (pmc_close_logfile() < 0)
err(EX_OSERR, "ERROR: logging failed");
}
return (args->pa_flags & FLAG_HAS_PIPE ? PMCSTAT_EXITING :
PMCSTAT_FINISHED);
}
/*
* Initialize module.
*/
void
pmcstat_initialize_logging(struct pmcstat_process **pmcstat_kernproc,
struct pmcstat_args *args, struct pmc_plugins *plugins,
int *pmcstat_npmcs, int *pmcstat_mergepmc)
{
struct pmcstat_process *pmcstat_kp;
int i;
/* use a convenient format for 'ldd' output */
if (setenv("LD_TRACE_LOADED_OBJECTS_FMT1","%o \"%p\" %x\n",1) != 0)
err(EX_OSERR, "ERROR: Cannot setenv");
/* Initialize hash tables */
pmcstat_string_initialize();
for (i = 0; i < PMCSTAT_NHASH; i++) {
LIST_INIT(&pmcstat_image_hash[i]);
LIST_INIT(&pmcstat_process_hash[i]);
}
/*
* Create a fake 'process' entry for the kernel with pid -1.
* hwpmc(4) will subsequently inform us about where the kernel
* and any loaded kernel modules are mapped.
*/
if ((pmcstat_kp = pmcstat_process_lookup((pid_t) -1,
PMCSTAT_ALLOCATE)) == NULL)
err(EX_OSERR, "ERROR: Cannot initialize logging");
*pmcstat_kernproc = pmcstat_kp;
/* PMC count. */
*pmcstat_npmcs = 0;
/* Merge PMC with same name. */
*pmcstat_mergepmc = args->pa_mergepmc;
/*
* Initialize plugins
*/
if (plugins[args->pa_pplugin].pl_init != NULL)
plugins[args->pa_pplugin].pl_init();
if (plugins[args->pa_plugin].pl_init != NULL)
plugins[args->pa_plugin].pl_init();
}
/*
* Shutdown module.
*/
void
pmcstat_shutdown_logging(struct pmcstat_args *args,
struct pmc_plugins *plugins,
struct pmcstat_stats *pmcstat_stats)
{
struct pmcstat_image *pi, *pitmp;
struct pmcstat_process *pp, *pptmp;
struct pmcstat_pcmap *ppm, *ppmtmp;
FILE *mf;
int i;
/* determine where to send the map file */
mf = NULL;
if (args->pa_mapfilename != NULL)
mf = (strcmp(args->pa_mapfilename, "-") == 0) ?
args->pa_printfile : fopen(args->pa_mapfilename, "w");
if (mf == NULL && args->pa_flags & FLAG_DO_GPROF &&
args->pa_verbosity >= 2)
mf = args->pa_printfile;
if (mf)
(void) fprintf(mf, "MAP:\n");
/*
* Shutdown the plugins
*/
if (plugins[args->pa_plugin].pl_shutdown != NULL)
plugins[args->pa_plugin].pl_shutdown(mf);
if (plugins[args->pa_pplugin].pl_shutdown != NULL)
plugins[args->pa_pplugin].pl_shutdown(mf);
for (i = 0; i < PMCSTAT_NHASH; i++) {
LIST_FOREACH_SAFE(pi, &pmcstat_image_hash[i], pi_next,
pitmp) {
if (plugins[args->pa_plugin].pl_shutdownimage != NULL)
plugins[args->pa_plugin].pl_shutdownimage(pi);
if (plugins[args->pa_pplugin].pl_shutdownimage != NULL)
plugins[args->pa_pplugin].pl_shutdownimage(pi);
free(pi->pi_symbols);
if (pi->pi_addr2line != NULL)
pclose(pi->pi_addr2line);
LIST_REMOVE(pi, pi_next);
free(pi);
}
LIST_FOREACH_SAFE(pp, &pmcstat_process_hash[i], pp_next,
pptmp) {
TAILQ_FOREACH_SAFE(ppm, &pp->pp_map, ppm_next, ppmtmp) {
TAILQ_REMOVE(&pp->pp_map, ppm, ppm_next);
free(ppm);
}
LIST_REMOVE(pp, pp_next);
free(pp);
}
}
pmcstat_string_shutdown();
/*
* Print errors unless -q was specified. Print all statistics
* if verbosity > 1.
*/
#define PRINT(N,V) do { \
if (pmcstat_stats->ps_##V || args->pa_verbosity >= 2) \
(void) fprintf(args->pa_printfile, " %-40s %d\n",\
N, pmcstat_stats->ps_##V); \
} while (0)
if (args->pa_verbosity >= 1 && (args->pa_flags & FLAG_DO_ANALYSIS)) {
(void) fprintf(args->pa_printfile, "CONVERSION STATISTICS:\n");
PRINT("#exec/a.out", exec_aout);
PRINT("#exec/elf", exec_elf);
PRINT("#exec/unknown", exec_indeterminable);
PRINT("#exec handling errors", exec_errors);
PRINT("#samples/total", samples_total);
PRINT("#samples/unclaimed", samples_unknown_offset);
PRINT("#samples/unknown-object", samples_indeterminable);
PRINT("#samples/unknown-function", samples_unknown_function);
PRINT("#callchain/dubious-frames", callchain_dubious_frames);
}
if (mf)
(void) fclose(mf);
}