Commit aa57fa70 authored by Witold Krecicki's avatar Witold Krecicki Committed by Evan Hunt

implement hazard pointer data structure

this is a mechanism to allow safe lock-free data structures.
parent ae202e0e
......@@ -50,8 +50,8 @@ OBJS = pk11.@O@ pk11_result.@O@ \
backtrace.@O@ base32.@O@ base64.@O@ \
bind9.@O@ buffer.@O@ bufferlist.@O@ \
commandline.@O@ counter.@O@ crc64.@O@ error.@O@ entropy.@O@ \
event.@O@ hash.@O@ ht.@O@ heap.@O@ hex.@O@ hmac.@O@ \
httpd.@O@ iterated_hash.@O@ \
event.@O@ hash.@O@ ht.@O@ heap.@O@ hex.@O@ \
hmac.@O@ hp.@O@ httpd.@O@ iterated_hash.@O@ \
lex.@O@ lfsr.@O@ lib.@O@ log.@O@ \
md.@O@ mem.@O@ mutexblock.@O@ \
netaddr.@O@ netscope.@O@ nonce.@O@ openssl_shim.@O@ pool.@O@ \
......@@ -69,8 +69,8 @@ SRCS = pk11.c pk11_result.c \
aes.c app.c assertions.c \
backtrace.c base32.c base64.c bind9.c \
buffer.c bufferlist.c commandline.c counter.c crc64.c \
entropy.c error.c event.c hash.c ht.c heap.c hex.c hmac.c \
httpd.c iterated_hash.c \
entropy.c error.c event.c hash.c ht.c heap.c \
hex.c hmac.c hp.c httpd.c iterated_hash.c \
lex.c lfsr.c lib.c log.c \
md.c mem.c mutexblock.c \
netaddr.c netscope.c nonce.c openssl_shim.c pool.c \
......
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*
* Hazard Pointer implementation.
*
* This work is based on C++ code available from:
* https://github.com/pramalhe/ConcurrencyFreaks/
*
* Copyright (c) 2014-2016, Pedro Ramalhete, Andreia Correia
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Concurrency Freaks nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER>
* 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 <inttypes.h>
#include <isc/atomic.h>
#include <isc/hp.h>
#include <isc/string.h>
#include <isc/mem.h>
#include <isc/util.h>
#define HP_MAX_THREADS 128
#define HP_MAX_HPS 4 /* This is named 'K' in the HP paper */
#define CLPAD (128 / sizeof(uintptr_t))
#define HP_THRESHOLD_R 0 /* This is named 'R' in the HP paper */
/* Maximum number of retired objects per thread */
#define MAX_RETIRED (HP_MAX_THREADS * HP_MAX_HPS)
#define TID_UNKNOWN -1
static atomic_int_fast32_t tid_v_base;
static bool tid_v_initialized;
#if defined(HAVE_TLS)
#if defined(HAVE_THREAD_LOCAL)
#include <threads.h>
static thread_local int tid_v = TID_UNKNOWN;
#elif defined(HAVE___THREAD)
static __thread int tid_v = TID_UNKNOWN;
#elif defined(HAVE___DECLSPEC_THREAD)
static __declspec( thread ) int tid_v = TID_UNKNOWN;
#else /* if defined(HAVE_THREAD_LOCAL) */
#error "Unknown method for defining a TLS variable!"
#endif /* if defined(HAVE_THREAD_LOCAL) */
#else /* if defined(HAVE_TLS) */
#error "Thread-local storage support is required!"
#endif /* if defined(HAVE_TLS) */
typedef struct retirelist {
int size;
uintptr_t list[MAX_RETIRED];
} retirelist_t;
struct isc_hp {
int max_hps;
isc_mem_t *mctx;
atomic_uintptr_t *hp[HP_MAX_THREADS];
retirelist_t *rl[HP_MAX_THREADS];
isc_hp_deletefunc_t *deletefunc;
};
static inline int
tid() {
if (!tid_v_initialized) {
atomic_init(&tid_v_base, 0);
tid_v_initialized = true;
}
if (tid_v == TID_UNKNOWN) {
tid_v = atomic_fetch_add(&tid_v_base, 1);
REQUIRE(tid_v < HP_MAX_THREADS);
}
return (tid_v);
}
isc_hp_t *
isc_hp_new(isc_mem_t *mctx, size_t max_hps, isc_hp_deletefunc_t *deletefunc) {
isc_hp_t *hp = isc_mem_get(mctx, sizeof(*hp));
if (max_hps == 0) {
max_hps = HP_MAX_HPS;
}
*hp = (isc_hp_t){
.max_hps = max_hps,
.deletefunc = deletefunc
};
isc_mem_attach(mctx, &hp->mctx);
for (int i = 0; i < HP_MAX_THREADS; i++) {
hp->hp[i] = isc_mem_get(mctx, CLPAD * 2 * sizeof(hp->hp[i][0]));
hp->rl[i] = isc_mem_get(mctx, sizeof(*hp->rl[0]));
*hp->rl[i] = (retirelist_t) { .size = 0 };
for (int j = 0; j < hp->max_hps; j++) {
atomic_init(&hp->hp[i][j], 0);
}
}
return (hp);
}
void
isc_hp_destroy(isc_hp_t *hp) {
for (int i = 0; i < HP_MAX_THREADS; i++) {
isc_mem_put(hp->mctx, hp->hp[i],
CLPAD * 2 * sizeof(uintptr_t));
for (int j = 0; j < hp->rl[i]->size; j++) {
void *data = (void *)hp->rl[i]->list[j];
hp->deletefunc(data);
}
isc_mem_put(hp->mctx, hp->rl[i], sizeof(*hp->rl[0]));
}
isc_mem_putanddetach(&hp->mctx, hp, sizeof(*hp));
}
void
isc_hp_clear(isc_hp_t *hp) {
for (int i = 0; i < hp->max_hps; i++) {
atomic_store_release(&hp->hp[tid()][i], 0);
}
}
void isc_hp_clear_one(isc_hp_t *hp, int ihp) {
atomic_store_release(&hp->hp[tid()][ihp], 0);
}
uintptr_t
isc_hp_protect(isc_hp_t *hp, int ihp, atomic_uintptr_t *atom) {
uintptr_t n = 0;
uintptr_t ret;
while ((ret = atomic_load(atom)) != n) {
atomic_store(&hp->hp[tid()][ihp], ret);
n = ret;
}
return (ret);
}
uintptr_t
isc_hp_protect_ptr(isc_hp_t *hp, int ihp, atomic_uintptr_t ptr) {
atomic_store(&hp->hp[tid()][ihp], atomic_load(&ptr));
return (atomic_load(&ptr));
}
uintptr_t
isc_hp_protect_release(isc_hp_t *hp, int ihp, atomic_uintptr_t ptr) {
atomic_store_release(&hp->hp[tid()][ihp], atomic_load(&ptr));
return (atomic_load(&ptr));
}
void
isc_hp_retire(isc_hp_t *hp, uintptr_t ptr) {
hp->rl[tid()]->list[hp->rl[tid()]->size++] = ptr;
INSIST(hp->rl[tid()]->size < MAX_RETIRED);
if (hp->rl[tid()]->size < HP_THRESHOLD_R) {
return;
}
for (int iret = 0; iret < hp->rl[tid()]->size; iret++) {
uintptr_t obj = hp->rl[tid()]->list[iret];
bool can_delete = true;
for (int itid = 0;
itid < HP_MAX_THREADS && can_delete;
itid++)
{
for (int ihp = hp->max_hps-1; ihp >= 0; ihp--) {
if (atomic_load(&hp->hp[itid][ihp]) == obj) {
can_delete = false;
break;
}
}
}
if (can_delete) {
size_t bytes = (hp->rl[tid()]->size - iret) *
sizeof(hp->rl[tid()]->list[0]);
memmove(&hp->rl[tid()]->list[iret],
&hp->rl[tid()]->list[iret + 1],
bytes);
hp->rl[tid()]->size--;
hp->deletefunc((void *)obj);
}
}
}
......@@ -23,7 +23,7 @@ HEADERS = aes.h app.h assertions.h atomic.h backtrace.h \
commandline.h counter.h crc64.h deprecated.h \
endian.h errno.h error.h event.h eventclass.h \
file.h formatcheck.h fsaccess.h fuzz.h \
hash.h heap.h hex.h hmac.h ht.h httpd.h \
hash.h heap.h hex.h hmac.h hp.h ht.h httpd.h \
interfaceiter.h iterated_hash.h \
lang.h lex.h lfsr.h lib.h likely.h list.h log.h \
magic.h md.h mem.h meminfo.h mutexblock.h \
......
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*
* Hazard Pointer implementation.
*
* This work is based on C++ code available from:
* https://github.com/pramalhe/ConcurrencyFreaks/
*
* Copyright (c) 2014-2016, Pedro Ramalhete, Andreia Correia
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Concurrency Freaks nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER>
* 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 <isc/atomic.h>
#include <isc/string.h>
#include <isc/mem.h>
#include <isc/types.h>
#include <isc/util.h>
/*%
* Hazard pointers are a mechanism for protecting objects in memory
* from being deleted by other threads while in use. This allows
* safe lock-free data structures.
*
* This is an adaptation of the ConcurrencyFreaks implementation in C.
* More details available at https://github.com/pramalhe/ConcurrencyFreaks,
* in the file HazardPointers.hpp.
*/
typedef void
(isc_hp_deletefunc_t)(void *);
isc_hp_t *
isc_hp_new(isc_mem_t *mctx, size_t max_hps, isc_hp_deletefunc_t *deletefunc);
/*%<
* Create a new hazard pointer array of size 'max_hps' (or a reasonable
* default value if 'max_hps' is 0). The function 'deletefunc' will be
* used to delete objects protected by hazard pointers when it becomes
* safe to retire them.
*/
void
isc_hp_destroy(isc_hp_t *hp);
/*%<
* Destroy a hazard pointer array and clean up all objects protected
* by hazard pointers.
*/
void
isc_hp_clear(isc_hp_t *hp);
/*%<
* Clear all hazard pointers in the array for the current thread.
*
* Progress condition: wait-free bounded (by max_hps)
*/
void
isc_hp_clear_one(isc_hp_t *hp, int ihp);
/*%<
* Clear a specified hazard pointer in the array for the current thread.
*
* Progress condition: wait-free population oblivious.
*/
uintptr_t
isc_hp_protect(isc_hp_t *hp, int ihp, atomic_uintptr_t *atom);
/*%<
* Protect an object referenced by 'atom' with a hazard pointer for the
* current thread.
*
* Progress condition: lock-free.
*/
uintptr_t
isc_hp_protect_ptr(isc_hp_t *hp, int ihp, atomic_uintptr_t ptr);
/*%<
* This returns the same value that is passed as ptr, which is sometimes
* useful.
*
* Progress condition: wait-free population oblivious.
*/
uintptr_t
isc_hp_protect_release(isc_hp_t *hp, int ihp, atomic_uintptr_t ptr);
/*%<
* Same as isc_hp_protect_ptr(), but explicitly uses memory_order_release.
*
* Progress condition: wait-free population oblivious.
*/
void
isc_hp_retire(isc_hp_t *hp, uintptr_t ptr);
/*%<
* Retire an object that is no longer in use by any thread, calling
* the delete function that was specified in isc_hp_new().
*
* Progress condition: wait-free bounded (by the number of threads squared)
*/
......@@ -43,6 +43,8 @@ typedef ISC_LIST(isc_event_t) isc_eventlist_t; /*%< Event List */
typedef unsigned int isc_eventtype_t; /*%< Event Type */
typedef uint32_t isc_fsaccess_t; /*%< FS Access */
typedef struct isc_hash isc_hash_t; /*%< Hash */
typedef struct isc_hp isc_hp_t; /*%< Hazard
pointer */
typedef struct isc_httpd isc_httpd_t; /*%< HTTP client */
typedef void (isc_httpdfree_t)(isc_buffer_t *, void *); /*%< HTTP free function */
typedef struct isc_httpdmgr isc_httpdmgr_t; /*%< HTTP manager */
......
......@@ -242,6 +242,13 @@ isc_heap_insert
isc_hex_decodestring
isc_hex_tobuffer
isc_hex_totext
isc_hp_clear
isc_hp_destroy
isc_hp_protect
isc_hp_protect_ptr
isc_hp_protect_release
isc_hp_new
isc_hp_retire
isc_hmac
isc_hmac_new
isc_hmac_free
......@@ -252,6 +259,13 @@ isc_hmac_final
isc_hmac_get_md_type
isc_hmac_get_size
isc_hmac_get_block_size
isc_hp_new
isc_hp_destroy
isc_hp_clear
isc_hp_protect
isc_hp_protect_ptr
isc_hp_protect_release
isc_hp_retire
isc_ht_add
isc_ht_count
isc_ht_delete
......
......@@ -104,6 +104,9 @@
<ClInclude Include="..\include\isc\hmac.h">
<Filter>Library Header Files</Filter>
</ClInclude>
<ClInclude Include="..\include\isc\hp.h">
<Filter>Library Header Files</Filter>
</ClInclude>
<ClInclude Include="..\include\isc\ht.h">
<Filter>Library Header Files</Filter>
</ClInclude>
......@@ -500,6 +503,9 @@
<ClCompile Include="..\hmac.c">
<Filter>Library Source Files</Filter>
</ClCompile>
<ClCompile Include="..\hp.c">
<Filter>Library Source Files</Filter>
</ClCompile>
<ClCompile Include="..\ht.c">
<Filter>Library Source Files</Filter>
</ClCompile>
......
......@@ -311,6 +311,7 @@ copy InstallFiles ..\Build\Release\
<ClInclude Include="..\include\isc\heap.h" />
<ClInclude Include="..\include\isc\hex.h" />
<ClInclude Include="..\include\isc\hmac.h" />
<ClInclude Include="..\include\isc\hp.h" />
<ClInclude Include="..\include\isc\ht.h" />
<ClInclude Include="..\include\isc\httpd.h" />
<ClInclude Include="..\include\isc\interfaceiter.h" />
......@@ -421,6 +422,7 @@ copy InstallFiles ..\Build\Release\
<ClCompile Include="..\heap.c" />
<ClCompile Include="..\hex.c" />
<ClCompile Include="..\hmac.c" />
<ClCompile Include="..\hp.c" />
<ClCompile Include="..\ht.c" />
<ClCompile Include="..\httpd.c" />
<ClCompile Include="..\iterated_hash.c" />
......
......@@ -2148,6 +2148,7 @@
./lib/isc/heap.c C 1997,1998,1999,2000,2001,2004,2005,2006,2007,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019
./lib/isc/hex.c C 2000,2001,2002,2003,2004,2005,2007,2008,2013,2014,2015,2016,2018,2019
./lib/isc/hmac.c C 2000,2001,2004,2005,2006,2007,2009,2011,2012,2013,2014,2015,2016,2017,2018,2019
./lib/isc/hp.c C 2019
./lib/isc/ht.c C 2016,2017,2018,2019
./lib/isc/httpd.c C 2006,2007,2008,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019
./lib/isc/include/Makefile.in MAKE 1998,1999,2000,2001,2004,2007,2012,2014,2016,2018,2019
......@@ -2179,6 +2180,7 @@
./lib/isc/include/isc/heap.h C 1997,1998,1999,2000,2001,2004,2005,2006,2007,2009,2012,2016,2018,2019
./lib/isc/include/isc/hex.h C 2000,2001,2004,2005,2006,2007,2008,2016,2018,2019
./lib/isc/include/isc/hmac.h C 2000,2001,2004,2005,2006,2007,2009,2011,2012,2013,2014,2015,2016,2017,2018,2019
./lib/isc/include/isc/hp.h C 2019
./lib/isc/include/isc/ht.h C 2016,2017,2018,2019
./lib/isc/include/isc/httpd.h C 2006,2007,2008,2014,2016,2018,2019
./lib/isc/include/isc/interfaceiter.h C 1999,2000,2001,2004,2005,2006,2007,2016,2018,2019
......
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