/*-
* Copyright (c) 2005-2007 Joseph Koshy
* Copyright (c) 2007 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by A. Joseph Koshy under
* sponsorship from the FreeBSD Foundation and Google, Inc.
*
* 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/param.h>
#include <sys/pmc.h>
#include <sys/pmclog.h>
#include <assert.h>
#include <errno.h>
#include <pmc.h>
#include <pmclog.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <machine/pmc_mdep.h>
#include "libpmcinternal.h"
#define PMCLOG_BUFFER_SIZE 4096
/*
* API NOTES
*
* The pmclog(3) API is oriented towards parsing an event stream in
* "realtime", i.e., from an data source that may or may not preserve
* record boundaries -- for example when the data source is elsewhere
* on a network. The API allows data to be fed into the parser zero
* or more bytes at a time.
*
* The state for a log file parser is maintained in a 'struct
* pmclog_parse_state'. Parser invocations are done by calling
* 'pmclog_read()'; this function will inform the caller when a
* complete event is parsed.
*
* The parser first assembles a complete log file event in an internal
* work area (see "ps_saved" below). Once a complete log file event
* is read, the parser then parses it and converts it to an event
* descriptor usable by the client. We could possibly avoid this two
* step process by directly parsing the input log to set fields in the
* event record. However the parser's state machine would get
* insanely complicated, and this code is unlikely to be used in
* performance critical paths.
*/
enum pmclog_parser_state {
PL_STATE_NEW_RECORD, /* in-between records */
PL_STATE_EXPECTING_HEADER, /* header being read */
PL_STATE_PARTIAL_RECORD, /* header present but not the record */
PL_STATE_ERROR /* parsing error encountered */
};
struct pmclog_parse_state {
enum pmclog_parser_state ps_state;
enum pmc_cputype ps_arch; /* log file architecture */
uint32_t ps_version; /* hwpmc version */
int ps_initialized; /* whether initialized */
int ps_count; /* count of records processed */
off_t ps_offset; /* stream byte offset */
union pmclog_entry ps_saved; /* saved partial log entry */
int ps_svcount; /* #bytes saved */
int ps_fd; /* active fd or -1 */
char *ps_buffer; /* scratch buffer if fd != -1 */
char *ps_data; /* current parse pointer */
size_t ps_len; /* length of buffered data */
};
#define PMCLOG_HEADER_FROM_SAVED_STATE(PS) \
(* ((uint32_t *) &(PS)->ps_saved))
#define PMCLOG_INITIALIZE_READER(LE,A) LE = (uint32_t *) &(A)
#define PMCLOG_READ32(LE,V) do { \
(V) = *(LE)++; \
} while (0)
#define PMCLOG_READ64(LE,V) do { \
uint64_t _v; \
_v = (uint64_t) *(LE)++; \
_v |= ((uint64_t) *(LE)++) << 32; \
(V) = _v; \
} while (0)
#define PMCLOG_READSTRING(LE,DST,LEN) strlcpy((DST), (char *) (LE), (LEN))
/*
* Assemble a log record from '*len' octets starting from address '*data'.
* Update 'data' and 'len' to reflect the number of bytes consumed.
*
* '*data' is potentially an unaligned address and '*len' octets may
* not be enough to complete a event record.
*/
static enum pmclog_parser_state
pmclog_get_record(struct pmclog_parse_state *ps, char **data, ssize_t *len)
{
int avail, copylen, recordsize, used;
uint32_t h;
const int HEADERSIZE = sizeof(uint32_t);
char *src, *dst;
if ((avail = *len) <= 0)
return (ps->ps_state = PL_STATE_ERROR);
src = *data;
h = used = 0;
if (ps->ps_state == PL_STATE_NEW_RECORD)
ps->ps_svcount = 0;
dst = (char *) &ps->ps_saved + ps->ps_svcount;
switch (ps->ps_state) {
case PL_STATE_NEW_RECORD:
/*
* Transitions:
*
* Case A: avail < headersize
* -> 'expecting header'
*
* Case B: avail >= headersize
* B.1: avail < recordsize
* -> 'partial record'
* B.2: avail >= recordsize
* -> 'new record'
*/
copylen = avail < HEADERSIZE ? avail : HEADERSIZE;
bcopy(src, dst, copylen);
ps->ps_svcount = used = copylen;
if (copylen < HEADERSIZE) {
ps->ps_state = PL_STATE_EXPECTING_HEADER;
goto done;
}
src += copylen;
dst += copylen;
h = PMCLOG_HEADER_FROM_SAVED_STATE(ps);
recordsize = PMCLOG_HEADER_TO_LENGTH(h);
if (recordsize <= 0)
goto error;
if (recordsize <= avail) { /* full record available */
bcopy(src, dst, recordsize - copylen);
ps->ps_svcount = used = recordsize;
goto done;
}
/* header + a partial record is available */
bcopy(src, dst, avail - copylen);
ps->ps_svcount = used = avail;
ps->ps_state = PL_STATE_PARTIAL_RECORD;
break;
case PL_STATE_EXPECTING_HEADER:
/*
* Transitions:
*
* Case C: avail+saved < headersize
* -> 'expecting header'
*
* Case D: avail+saved >= headersize
* D.1: avail+saved < recordsize
* -> 'partial record'
* D.2: avail+saved >= recordsize
* -> 'new record'
* (see PARTIAL_RECORD handling below)
*/
if (avail + ps->ps_svcount < HEADERSIZE) {
bcopy(src, dst, avail);
ps->ps_svcount += avail;
used = avail;
break;
}
used = copylen = HEADERSIZE - ps->ps_svcount;
bcopy(src, dst, copylen);
src += copylen;
dst += copylen;
avail -= copylen;
ps->ps_svcount += copylen;
/*FALLTHROUGH*/
case PL_STATE_PARTIAL_RECORD:
/*
* Transitions:
*
* Case E: avail+saved < recordsize
* -> 'partial record'
*
* Case F: avail+saved >= recordsize
* -> 'new record'
*/
h = PMCLOG_HEADER_FROM_SAVED_STATE(ps);
recordsize = PMCLOG_HEADER_TO_LENGTH(h);
if (recordsize <= 0)
goto error;
if (avail + ps->ps_svcount < recordsize) {
copylen = avail;
ps->ps_state = PL_STATE_PARTIAL_RECORD;
} else {
copylen = recordsize - ps->ps_svcount;
ps->ps_state = PL_STATE_NEW_RECORD;
}
bcopy(src, dst, copylen);
ps->ps_svcount += copylen;
used += copylen;
break;
default:
goto error;
}
done:
*data += used;
*len -= used;
return ps->ps_state;
error:
ps->ps_state = PL_STATE_ERROR;
return ps->ps_state;
}
/*
* Get an event from the stream pointed to by '*data'. '*len'
* indicates the number of bytes available to parse. Arguments
* '*data' and '*len' are updated to indicate the number of bytes
* consumed.
*/
static int
pmclog_get_event(void *cookie, char **data, ssize_t *len,
struct pmclog_ev *ev)
{
int evlen, pathlen;
uint32_t h, *le, npc;
enum pmclog_parser_state e;
struct pmclog_parse_state *ps;
ps = (struct pmclog_parse_state *) cookie;
assert(ps->ps_state != PL_STATE_ERROR);
if ((e = pmclog_get_record(ps,data,len)) == PL_STATE_ERROR) {
ev->pl_state = PMCLOG_ERROR;
return -1;
}
if (e != PL_STATE_NEW_RECORD) {
ev->pl_state = PMCLOG_REQUIRE_DATA;
return -1;
}
PMCLOG_INITIALIZE_READER(le, ps->ps_saved);
PMCLOG_READ32(le,h);
if (!PMCLOG_HEADER_CHECK_MAGIC(h)) {
ps->ps_state = PL_STATE_ERROR;
ev->pl_state = PMCLOG_ERROR;
return -1;
}
/* copy out the time stamp */
PMCLOG_READ32(le,ev->pl_ts.tv_sec);
PMCLOG_READ32(le,ev->pl_ts.tv_nsec);
evlen = PMCLOG_HEADER_TO_LENGTH(h);
#define PMCLOG_GET_PATHLEN(P,E,TYPE) do { \
(P) = (E) - offsetof(struct TYPE, pl_pathname); \
if ((P) > PATH_MAX || (P) < 0) \
goto error; \
} while (0)
#define PMCLOG_GET_CALLCHAIN_SIZE(SZ,E) do { \
(SZ) = ((E) - offsetof(struct pmclog_callchain, pl_pc)) \
/ sizeof(uintfptr_t); \
} while (0);
switch (ev->pl_type = PMCLOG_HEADER_TO_TYPE(h)) {
case PMCLOG_TYPE_CALLCHAIN:
PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pid);
PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_cc.pl_cpuflags);
PMCLOG_GET_CALLCHAIN_SIZE(ev->pl_u.pl_cc.pl_npc,evlen);
for (npc = 0; npc < ev->pl_u.pl_cc.pl_npc; npc++)
PMCLOG_READADDR(le,ev->pl_u.pl_cc.pl_pc[npc]);
for (;npc < PMC_CALLCHAIN_DEPTH_MAX; npc++)
ev->pl_u.pl_cc.pl_pc[npc] = (uintfptr_t) 0;
break;
case PMCLOG_TYPE_CLOSELOG:
case PMCLOG_TYPE_DROPNOTIFY:
/* nothing to do */
break;
case PMCLOG_TYPE_INITIALIZE:
PMCLOG_READ32(le,ev->pl_u.pl_i.pl_version);
PMCLOG_READ32(le,ev->pl_u.pl_i.pl_arch);
ps->ps_version = ev->pl_u.pl_i.pl_version;
ps->ps_arch = ev->pl_u.pl_i.pl_arch;
ps->ps_initialized = 1;
break;
case PMCLOG_TYPE_MAP_IN:
PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_map_in);
PMCLOG_READ32(le,ev->pl_u.pl_mi.pl_pid);
PMCLOG_READADDR(le,ev->pl_u.pl_mi.pl_start);
PMCLOG_READSTRING(le, ev->pl_u.pl_mi.pl_pathname, pathlen);
break;
case PMCLOG_TYPE_MAP_OUT:
PMCLOG_READ32(le,ev->pl_u.pl_mo.pl_pid);
PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_start);
PMCLOG_READADDR(le,ev->pl_u.pl_mo.pl_end);
break;
case PMCLOG_TYPE_PCSAMPLE:
PMCLOG_READ32(le,ev->pl_u.pl_s.pl_pid);
PMCLOG_READADDR(le,ev->pl_u.pl_s.pl_pc);
PMCLOG_READ32(le,ev->pl_u.pl_s.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_s.pl_usermode);
break;
case PMCLOG_TYPE_PMCALLOCATE:
PMCLOG_READ32(le,ev->pl_u.pl_a.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_a.pl_event);
PMCLOG_READ32(le,ev->pl_u.pl_a.pl_flags);
if ((ev->pl_u.pl_a.pl_evname =
_pmc_name_of_event(ev->pl_u.pl_a.pl_event, ps->ps_arch))
== NULL)
goto error;
break;
case PMCLOG_TYPE_PMCALLOCATEDYN:
PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_event);
PMCLOG_READ32(le,ev->pl_u.pl_ad.pl_flags);
PMCLOG_READSTRING(le,ev->pl_u.pl_ad.pl_evname,PMC_NAME_MAX);
break;
case PMCLOG_TYPE_PMCATTACH:
PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_pmcattach);
PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_t.pl_pid);
PMCLOG_READSTRING(le,ev->pl_u.pl_t.pl_pathname,pathlen);
break;
case PMCLOG_TYPE_PMCDETACH:
PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pmcid);
PMCLOG_READ32(le,ev->pl_u.pl_d.pl_pid);
break;
case PMCLOG_TYPE_PROCCSW:
PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pmcid);
PMCLOG_READ64(le,ev->pl_u.pl_c.pl_value);
PMCLOG_READ32(le,ev->pl_u.pl_c.pl_pid);
break;
case PMCLOG_TYPE_PROCEXEC:
PMCLOG_GET_PATHLEN(pathlen,evlen,pmclog_procexec);
PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pid);
PMCLOG_READADDR(le,ev->pl_u.pl_x.pl_entryaddr);
PMCLOG_READ32(le,ev->pl_u.pl_x.pl_pmcid);
PMCLOG_READSTRING(le,ev->pl_u.pl_x.pl_pathname,pathlen);
break;
case PMCLOG_TYPE_PROCEXIT:
PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pmcid);
PMCLOG_READ64(le,ev->pl_u.pl_e.pl_value);
PMCLOG_READ32(le,ev->pl_u.pl_e.pl_pid);
break;
case PMCLOG_TYPE_PROCFORK:
PMCLOG_READ32(le,ev->pl_u.pl_f.pl_oldpid);
PMCLOG_READ32(le,ev->pl_u.pl_f.pl_newpid);
break;
case PMCLOG_TYPE_SYSEXIT:
PMCLOG_READ32(le,ev->pl_u.pl_se.pl_pid);
break;
case PMCLOG_TYPE_USERDATA:
PMCLOG_READ32(le,ev->pl_u.pl_u.pl_userdata);
break;
default: /* unknown record type */
ps->ps_state = PL_STATE_ERROR;
ev->pl_state = PMCLOG_ERROR;
return (-1);
}
ev->pl_offset = (ps->ps_offset += evlen);
ev->pl_count = (ps->ps_count += 1);
ev->pl_state = PMCLOG_OK;
return 0;
error:
ev->pl_state = PMCLOG_ERROR;
ps->ps_state = PL_STATE_ERROR;
return -1;
}
/*
* Extract and return the next event from the byte stream.
*
* Returns 0 and sets the event's state to PMCLOG_OK in case an event
* was successfully parsed. Otherwise this function returns -1 and
* sets the event's state to one of PMCLOG_REQUIRE_DATA (if more data
* is needed) or PMCLOG_EOF (if an EOF was seen) or PMCLOG_ERROR if
* a parse error was encountered.
*/
int
pmclog_read(void *cookie, struct pmclog_ev *ev)
{
int retval;
ssize_t nread;
struct pmclog_parse_state *ps;
ps = (struct pmclog_parse_state *) cookie;
if (ps->ps_state == PL_STATE_ERROR) {
ev->pl_state = PMCLOG_ERROR;
return -1;
}
/*
* If there isn't enough data left for a new event try and get
* more data.
*/
if (ps->ps_len == 0) {
ev->pl_state = PMCLOG_REQUIRE_DATA;
/*
* If we have a valid file descriptor to read from, attempt
* to read from that. This read may return with an error,
* (which may be EAGAIN or other recoverable error), or
* can return EOF.
*/
if (ps->ps_fd != PMCLOG_FD_NONE) {
refill:
nread = read(ps->ps_fd, ps->ps_buffer,
PMCLOG_BUFFER_SIZE);
if (nread <= 0) {
if (nread == 0)
ev->pl_state = PMCLOG_EOF;
else if (errno != EAGAIN) /* not restartable */
ev->pl_state = PMCLOG_ERROR;
return -1;
}
ps->ps_len = nread;
ps->ps_data = ps->ps_buffer;
} else
return -1;
}
assert(ps->ps_len > 0);
/* Retrieve one event from the byte stream. */
retval = pmclog_get_event(ps, &ps->ps_data, &ps->ps_len, ev);
/*
* If we need more data and we have a configured fd, try read
* from it.
*/
if (retval < 0 && ev->pl_state == PMCLOG_REQUIRE_DATA &&
ps->ps_fd != -1) {
assert(ps->ps_len == 0);
goto refill;
}
return retval;
}
/*
* Feed data to a memory based parser.
*
* The memory area pointed to by 'data' needs to be valid till the
* next error return from pmclog_next_event().
*/
int
pmclog_feed(void *cookie, char *data, int len)
{
struct pmclog_parse_state *ps;
ps = (struct pmclog_parse_state *) cookie;
if (len < 0 || /* invalid length */
ps->ps_buffer || /* called for a file parser */
ps->ps_len != 0) /* unnecessary call */
return -1;
ps->ps_data = data;
ps->ps_len = len;
return 0;
}
/*
* Allocate and initialize parser state.
*/
void *
pmclog_open(int fd)
{
struct pmclog_parse_state *ps;
if ((ps = (struct pmclog_parse_state *) malloc(sizeof(*ps))) == NULL)
return NULL;
ps->ps_state = PL_STATE_NEW_RECORD;
ps->ps_arch = -1;
ps->ps_initialized = 0;
ps->ps_count = 0;
ps->ps_offset = (off_t) 0;
bzero(&ps->ps_saved, sizeof(ps->ps_saved));
ps->ps_svcount = 0;
ps->ps_fd = fd;
ps->ps_data = NULL;
ps->ps_buffer = NULL;
ps->ps_len = 0;
/* allocate space for a work area */
if (ps->ps_fd != PMCLOG_FD_NONE) {
if ((ps->ps_buffer = malloc(PMCLOG_BUFFER_SIZE)) == NULL) {
free(ps);
return NULL;
}
}
return ps;
}
/*
* Free up parser state.
*/
void
pmclog_close(void *cookie)
{
struct pmclog_parse_state *ps;
ps = (struct pmclog_parse_state *) cookie;
if (ps->ps_buffer)
free(ps->ps_buffer);
free(ps);
}
