libumem/envvar.c
Wez Furlong 1028ce923e Sync with the current sources from onnv-gate.
The solaris sources use a non-portable create-thread-suspended flag when
spawning the update thread; I've thrown together a pthreads portable
equivalent.  This has not had any real level of testing.

These changes include a lock around the underlying brk() call; the lack of lock
in earlier revisions of this repo may be the reason that
UMEM_OPTIONS=backend=sbrk was flaky.
2010-06-26 16:02:39 +00:00

780 lines
18 KiB
C

/*
* 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 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Portions Copyright 2006-2008 Message Systems, Inc.
*/
/* #pragma ident "@(#)envvar.c 1.5 05/06/08 SMI" */
#include "config.h"
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#if HAVE_DLFCN_H
#include <dlfcn.h>
#endif
#include "umem_base.h"
#include "vmem_base.h"
/*
* A umem environment variable, like UMEM_DEBUG, is set to a series
* of items, seperated by ',':
*
* UMEM_DEBUG="audit=10,guards,firewall=512"
*
* This structure describes items. Each item has a name, type, and
* description. During processing, an item read from the user may
* be either "valid" or "invalid".
*
* A valid item has an argument, if required, and it is of the right
* form (doesn't overflow, doesn't contain any unexpected characters).
*
* If the item is valid, item_flag_target != NULL, and:
* type is not CLEARFLAG, then (*item_flag_target) |= item_flag_value
* type is CLEARFLAG, then (*item_flag_target) &= ~item_flag_value
*/
#define UMEM_ENV_ITEM_MAX 512
struct umem_env_item;
typedef int arg_process_t(const struct umem_env_item *item, const char *value);
#define ARG_SUCCESS 0 /* processing successful */
#define ARG_BAD 1 /* argument had a bad value */
typedef struct umem_env_item {
const char *item_name; /* tag in environment variable */
const char *item_interface_stability;
enum {
ITEM_INVALID,
ITEM_FLAG, /* only a flag. No argument allowed */
ITEM_CLEARFLAG, /* only a flag, but clear instead of set */
ITEM_OPTUINT, /* optional integer argument */
ITEM_UINT, /* required integer argument */
ITEM_OPTSIZE, /* optional size_t argument */
ITEM_SIZE, /* required size_t argument */
ITEM_SPECIAL /* special argument processing */
} item_type;
const char *item_description;
uint_t *item_flag_target; /* the variable containing the flag */
uint_t item_flag_value; /* the value to OR in */
uint_t *item_uint_target; /* the variable to hold the integer */
size_t *item_size_target;
arg_process_t *item_special; /* callback for special handling */
} umem_env_item_t;
#ifndef UMEM_STANDALONE
static arg_process_t umem_backend_process;
#endif
#ifdef __GLIBC__
/* replace getenv() with a specialized version that doesn't
* need to allocate memory. We can't use strlen or strcmp
* here. */
#include <unistd.h>
static char *safe_getenv(const char *name)
{
int i, l;
for (l = 0; name[l]; l++)
;
for (i = 0; __environ[i]; i++) {
if (!memcmp(__environ[i], name, l) && __environ[i][l] == '=') {
return &__environ[i][l+1];
}
}
return NULL;
}
#define getenv(x) safe_getenv(x)
#endif
static arg_process_t umem_log_process;
static size_t umem_size_tempval;
static arg_process_t umem_size_process;
const char *____umem_environ_msg_options = "-- UMEM_OPTIONS --";
static umem_env_item_t umem_options_items[] = {
#ifndef UMEM_STANDALONE
{ "backend", "Evolving", ITEM_SPECIAL,
"=sbrk for sbrk(2), =mmap for mmap(2)",
NULL, 0, NULL, NULL,
&umem_backend_process
},
#endif
{ "concurrency", "Private", ITEM_UINT,
"Max concurrency",
NULL, 0, &umem_max_ncpus
},
{ "max_contention", "Private", ITEM_UINT,
"Maximum contention in a reap interval before the depot is "
"resized.",
NULL, 0, &umem_depot_contention
},
{ "nomagazines", "Private", ITEM_FLAG,
"no caches will be multithreaded, and no caching will occur.",
&umem_flags, UMF_NOMAGAZINE
},
{ "reap_interval", "Private", ITEM_UINT,
"Minimum time between reaps and updates, in seconds.",
NULL, 0, &umem_reap_interval
},
{ "size_add", "Private", ITEM_SPECIAL,
"add a size to the cache size table",
NULL, 0, NULL,
&umem_size_tempval, &umem_size_process
},
{ "size_clear", "Private", ITEM_SPECIAL,
"clear all but the largest size from the cache size table",
NULL, 0, NULL,
&umem_size_tempval, &umem_size_process
},
{ "size_remove", "Private", ITEM_SPECIAL,
"remove a size from the cache size table",
NULL, 0, NULL,
&umem_size_tempval, &umem_size_process
},
#ifndef _WIN32
#ifndef UMEM_STANDALONE
{ "sbrk_minalloc", "Private", ITEM_SIZE,
"The minimum allocation chunk for the sbrk(2) heap.",
NULL, 0, NULL, &vmem_sbrk_minalloc
},
{ "sbrk_pagesize", "Private", ITEM_SIZE,
"The preferred page size for the sbrk(2) heap.",
NULL, 0, NULL, &vmem_sbrk_pagesize
},
#endif
#endif
{ NULL, "-- end of UMEM_OPTIONS --", ITEM_INVALID }
};
const char *____umem_environ_msg_debug = "-- UMEM_DEBUG --";
static umem_env_item_t umem_debug_items[] = {
{ "default", "Unstable", ITEM_FLAG,
"audit,contents,guards",
&umem_flags,
UMF_AUDIT | UMF_CONTENTS | UMF_DEADBEEF | UMF_REDZONE
},
{ "audit", "Unstable", ITEM_OPTUINT,
"Enable auditing. optionally =frames to set the number of "
"stored stack frames",
&umem_flags, UMF_AUDIT, &umem_stack_depth
},
{ "contents", "Unstable", ITEM_OPTSIZE,
"Enable contents storing. UMEM_LOGGING=contents also "
"required. optionally =bytes to set the number of stored "
"bytes",
&umem_flags, UMF_CONTENTS, NULL, &umem_content_maxsave
},
{ "guards", "Unstable", ITEM_FLAG,
"Enables guards and special patterns",
&umem_flags, UMF_DEADBEEF | UMF_REDZONE
},
{ "verbose", "Unstable", ITEM_FLAG,
"Enables writing error messages to stderr",
&umem_output, 1
},
{ "nosignal", "Private", ITEM_FLAG,
"Abort if called from a signal handler. Turns on 'audit'. "
"Note that this is not always a bug.",
&umem_flags, UMF_AUDIT | UMF_CHECKSIGNAL
},
{ "firewall", "Private", ITEM_SIZE,
"=minbytes. Every object >= minbytes in size will have its "
"end against an unmapped page",
&umem_flags, UMF_FIREWALL, NULL, &umem_minfirewall
},
{ "lite", "Private", ITEM_FLAG,
"debugging-lite",
&umem_flags, UMF_LITE
},
{ "maxverify", "Private", ITEM_SIZE,
"=maxbytes, Maximum bytes to check when 'guards' is active. "
"Normally all bytes are checked.",
NULL, 0, NULL, &umem_maxverify
},
{ "noabort", "Private", ITEM_CLEARFLAG,
"umem will not abort when a recoverable error occurs "
"(i.e. double frees, certain kinds of corruption)",
&umem_abort, 1
},
{ "mtbf", "Private", ITEM_UINT,
"=mtbf, the mean time between injected failures. Works best "
"if prime.\n",
NULL, 0, &umem_mtbf
},
{ "random", "Private", ITEM_FLAG,
"randomize flags on a per-cache basis",
&umem_flags, UMF_RANDOMIZE
},
{ "allverbose", "Private", ITEM_FLAG,
"Enables writing all logged messages to stderr",
&umem_output, 2
},
{ NULL, "-- end of UMEM_DEBUG --", ITEM_INVALID }
};
const char *____umem_environ_msg_logging = "-- UMEM_LOGGING --";
static umem_env_item_t umem_logging_items[] = {
{ "transaction", "Unstable", ITEM_SPECIAL,
"If 'audit' is set in UMEM_DEBUG, the audit structures "
"from previous transactions are entered into this log.",
NULL, 0, NULL,
&umem_transaction_log_size, &umem_log_process
},
{ "contents", "Unstable", ITEM_SPECIAL,
"If 'audit' is set in UMEM_DEBUG, the contents of objects "
"are recorded in this log as they are freed. If the "
"'contents' option is not set in UMEM_DEBUG, the first "
"256 bytes of each freed buffer will be saved.",
&umem_flags, UMF_CONTENTS, NULL,
&umem_content_log_size, &umem_log_process
},
{ "fail", "Unstable", ITEM_SPECIAL,
"Records are entered into this log for every failed "
"allocation.",
NULL, 0, NULL,
&umem_failure_log_size, &umem_log_process
},
{ "slab", "Private", ITEM_SPECIAL,
"Every slab created will be entered into this log.",
NULL, 0, NULL,
&umem_slab_log_size, &umem_log_process
},
{ NULL, "-- end of UMEM_LOGGING --", ITEM_INVALID }
};
typedef struct umem_envvar {
const char *env_name;
const char *env_func;
umem_env_item_t *env_item_list;
const char *env_getenv_result;
const char *env_func_result;
} umem_envvar_t;
static umem_envvar_t umem_envvars[] = {
{ "UMEM_DEBUG", "_umem_debug_init", umem_debug_items },
{ "UMEM_OPTIONS", "_umem_options_init", umem_options_items },
{ "UMEM_LOGGING", "_umem_logging_init", umem_logging_items },
{ NULL, NULL, NULL }
};
static umem_envvar_t *env_current;
#define CURRENT (env_current->env_name)
static int
empty(const char *str)
{
char c;
while ((c = *str) != '\0' && isspace(c))
str++;
return (*str == '\0');
}
static int
item_uint_process(const umem_env_item_t *item, const char *item_arg)
{
ulong_t result;
char *endptr = "";
int olderrno;
olderrno = errno;
errno = 0;
if (empty(item_arg)) {
goto badnumber;
}
result = strtoul(item_arg, &endptr, 10);
if (result == ULONG_MAX && errno == ERANGE) {
errno = olderrno;
goto overflow;
}
errno = olderrno;
if (*endptr != '\0')
goto badnumber;
if ((uint_t)result != result)
goto overflow;
(*item->item_uint_target) = (uint_t)result;
return (ARG_SUCCESS);
badnumber:
log_message("%s: %s: not a number\n", CURRENT, item->item_name);
return (ARG_BAD);
overflow:
log_message("%s: %s: overflowed\n", CURRENT, item->item_name);
return (ARG_BAD);
}
static int
item_size_process(const umem_env_item_t *item, const char *item_arg)
{
ulong_t result;
ulong_t result_arg;
char *endptr = "";
int olderrno;
if (empty(item_arg))
goto badnumber;
olderrno = errno;
errno = 0;
result_arg = strtoul(item_arg, &endptr, 10);
if (result_arg == ULONG_MAX && errno == ERANGE) {
errno = olderrno;
goto overflow;
}
errno = olderrno;
result = result_arg;
switch (*endptr) {
case 't':
case 'T':
result *= 1024;
if (result < result_arg)
goto overflow;
/*FALLTHRU*/
case 'g':
case 'G':
result *= 1024;
if (result < result_arg)
goto overflow;
/*FALLTHRU*/
case 'm':
case 'M':
result *= 1024;
if (result < result_arg)
goto overflow;
/*FALLTHRU*/
case 'k':
case 'K':
result *= 1024;
if (result < result_arg)
goto overflow;
endptr++; /* skip over the size character */
break;
default:
break; /* handled later */
}
if (*endptr != '\0')
goto badnumber;
(*item->item_size_target) = result;
return (ARG_SUCCESS);
badnumber:
log_message("%s: %s: not a number\n", CURRENT, item->item_name);
return (ARG_BAD);
overflow:
log_message("%s: %s: overflowed\n", CURRENT, item->item_name);
return (ARG_BAD);
}
static int
umem_log_process(const umem_env_item_t *item, const char *item_arg)
{
if (item_arg != NULL) {
int ret;
ret = item_size_process(item, item_arg);
if (ret != ARG_SUCCESS)
return (ret);
if (*item->item_size_target == 0)
return (ARG_SUCCESS);
} else
*item->item_size_target = 64*1024;
umem_logging = 1;
return (ARG_SUCCESS);
}
static int
umem_size_process(const umem_env_item_t *item, const char *item_arg)
{
const char *name = item->item_name;
void (*action_func)(size_t);
size_t result;
int ret;
if (strcmp(name, "size_clear") == 0) {
if (item_arg != NULL) {
log_message("%s: %s: does not take a value. ignored\n",
CURRENT, name);
return (ARG_BAD);
}
umem_alloc_sizes_clear();
return (ARG_SUCCESS);
} else if (strcmp(name, "size_add") == 0) {
action_func = umem_alloc_sizes_add;
} else if (strcmp(name, "size_remove") == 0) {
action_func = umem_alloc_sizes_remove;
} else {
log_message("%s: %s: internally unrecognized\n",
CURRENT, name, name, name);
return (ARG_BAD);
}
if (item_arg == NULL) {
log_message("%s: %s: requires a value. ignored\n",
CURRENT, name);
return (ARG_BAD);
}
ret = item_size_process(item, item_arg);
if (ret != ARG_SUCCESS)
return (ret);
result = *item->item_size_target;
action_func(result);
return (ARG_SUCCESS);
}
#ifndef UMEM_STANDALONE
static int
umem_backend_process(const umem_env_item_t *item, const char *item_arg)
{
const char *name = item->item_name;
if (item_arg == NULL)
goto fail;
if (strcmp(item_arg, "sbrk") == 0)
vmem_backend |= VMEM_BACKEND_SBRK;
else if (strcmp(item_arg, "mmap") == 0)
vmem_backend |= VMEM_BACKEND_MMAP;
else
goto fail;
return (ARG_SUCCESS);
fail:
log_message("%s: %s: must be %s=sbrk or %s=mmap\n",
CURRENT, name, name, name);
return (ARG_BAD);
}
#endif
static int
process_item(const umem_env_item_t *item, const char *item_arg)
{
int arg_required = 0;
arg_process_t *processor;
switch (item->item_type) {
case ITEM_FLAG:
case ITEM_CLEARFLAG:
case ITEM_OPTUINT:
case ITEM_OPTSIZE:
case ITEM_SPECIAL:
arg_required = 0;
break;
case ITEM_UINT:
case ITEM_SIZE:
arg_required = 1;
break;
}
switch (item->item_type) {
case ITEM_FLAG:
case ITEM_CLEARFLAG:
if (item_arg != NULL) {
log_message("%s: %s: does not take a value. ignored\n",
CURRENT, item->item_name);
return (1);
}
processor = NULL;
break;
case ITEM_UINT:
case ITEM_OPTUINT:
processor = item_uint_process;
break;
case ITEM_SIZE:
case ITEM_OPTSIZE:
processor = item_size_process;
break;
case ITEM_SPECIAL:
processor = item->item_special;
break;
default:
log_message("%s: %s: Invalid type. Ignored\n",
CURRENT, item->item_name);
return (1);
}
if (arg_required && item_arg == NULL) {
log_message("%s: %s: Required value missing\n",
CURRENT, item->item_name);
goto invalid;
}
if (item_arg != NULL || item->item_type == ITEM_SPECIAL) {
if (processor(item, item_arg) != ARG_SUCCESS)
goto invalid;
}
if (item->item_flag_target) {
if (item->item_type == ITEM_CLEARFLAG)
(*item->item_flag_target) &= ~item->item_flag_value;
else
(*item->item_flag_target) |= item->item_flag_value;
}
return (0);
invalid:
return (1);
}
#define ENV_SHORT_BYTES 10 /* bytes to print on error */
void
umem_process_value(umem_env_item_t *item_list, const char *beg, const char *end)
{
char buf[UMEM_ENV_ITEM_MAX];
char *argptr;
size_t count;
while (beg < end && isspace(*beg))
beg++;
while (beg < end && isspace(*(end - 1)))
end--;
if (beg >= end) {
log_message("%s: empty option\n", CURRENT);
return;
}
count = end - beg;
if (count + 1 > sizeof (buf)) {
char outbuf[ENV_SHORT_BYTES + 1];
/*
* Have to do this, since sprintf("%10s",...) calls malloc()
*/
(void) strncpy(outbuf, beg, ENV_SHORT_BYTES);
outbuf[ENV_SHORT_BYTES] = 0;
log_message("%s: argument \"%s...\" too long\n", CURRENT,
outbuf);
return;
}
(void) strncpy(buf, beg, count);
buf[count] = 0;
argptr = strchr(buf, '=');
if (argptr != NULL)
*argptr++ = 0;
for (; item_list->item_name != NULL; item_list++) {
if (strcmp(buf, item_list->item_name) == 0) {
(void) process_item(item_list, argptr);
return;
}
}
log_message("%s: '%s' not recognized\n", CURRENT, buf);
}
/*ARGSUSED*/
void
umem_setup_envvars(int invalid)
{
umem_envvar_t *cur_env;
static volatile enum {
STATE_START,
STATE_GETENV,
STATE_DLOPEN,
STATE_DLSYM,
STATE_FUNC,
STATE_DONE
} state = STATE_START;
#ifndef UMEM_STANDALONE
void *h;
#endif
if (invalid) {
const char *where;
/*
* One of the calls below invoked malloc() recursively. We
* remove any partial results and return.
*/
switch (state) {
case STATE_START:
where = "before getenv(3C) calls -- "
"getenv(3C) results ignored.";
break;
case STATE_GETENV:
where = "during getenv(3C) calls -- "
"getenv(3C) results ignored.";
break;
case STATE_DLOPEN:
where = "during dlopen(3C) call -- "
"_umem_*() results ignored.";
break;
case STATE_DLSYM:
where = "during dlsym(3C) call -- "
"_umem_*() results ignored.";
break;
case STATE_FUNC:
where = "during _umem_*() call -- "
"_umem_*() results ignored.";
break;
case STATE_DONE:
where = "after dlsym() or _umem_*() calls.";
break;
default:
where = "at unknown point -- "
"_umem_*() results ignored.";
break;
}
log_message("recursive allocation %s\n", where);
for (cur_env = umem_envvars; cur_env->env_name != NULL;
cur_env++) {
if (state == STATE_GETENV)
cur_env->env_getenv_result = NULL;
if (state != STATE_DONE)
cur_env->env_func_result = NULL;
}
state = STATE_DONE;
return;
}
state = STATE_GETENV;
for (cur_env = umem_envvars; cur_env->env_name != NULL; cur_env++) {
cur_env->env_getenv_result = getenv(cur_env->env_name);
if (state == STATE_DONE)
return; /* recursed */
}
#ifndef UMEM_STANDALONE
#ifdef _WIN32
# define dlopen(a, b) GetModuleHandle(NULL)
# define dlsym(a, b) GetProcAddress((HANDLE)a, b)
# define dlclose(a) 0
# define dlerror() 0
#endif
state = STATE_DLOPEN;
/* get a handle to the "a.out" object */
if ((h = dlopen(0, RTLD_FIRST | RTLD_LAZY)) != NULL) {
for (cur_env = umem_envvars; cur_env->env_name != NULL;
cur_env++) {
const char *(*func)(void);
const char *value;
state = STATE_DLSYM;
func = (const char *(*)(void))dlsym(h,
cur_env->env_func);
if (state == STATE_DONE)
break; /* recursed */
state = STATE_FUNC;
if (func != NULL) {
value = func();
if (state == STATE_DONE)
break; /* recursed */
cur_env->env_func_result = value;
}
}
(void) dlclose(h);
} else {
(void) dlerror(); /* snarf dlerror() */
}
#endif /* UMEM_STANDALONE */
state = STATE_DONE;
}
/*
* Process the environment variables.
*/
void
umem_process_envvars(void)
{
const char *value;
const char *end, *next;
umem_envvar_t *cur_env;
for (cur_env = umem_envvars; cur_env->env_name != NULL; cur_env++) {
env_current = cur_env;
value = cur_env->env_getenv_result;
if (value == NULL)
value = cur_env->env_func_result;
/* ignore if missing or empty */
if (value == NULL)
continue;
for (end = value; *end != '\0'; value = next) {
end = strchr(value, ',');
if (end != NULL)
next = end + 1; /* skip the comma */
else
next = end = value + strlen(value);
umem_process_value(cur_env->env_item_list, value, end);
}
}
}