+++ /dev/null
-/*
- * mem.spin: Promela code to validate memory barriers with OOO memory
- * and out-of-order instruction scheduling.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * Copyright (c) 2009 Mathieu Desnoyers
- */
-
-/* Promela validation variables. */
-
-/* specific defines "included" here */
-/* DEFINES file "included" here */
-
-#define NR_READERS 1
-#define NR_WRITERS 1
-
-#define NR_PROCS 2
-
-#define get_pid() (_pid)
-
-#define get_readerid() (get_pid())
-
-/*
- * Produced process control and data flow. Updated after each instruction to
- * show which variables are ready. Using one-hot bit encoding per variable to
- * save state space. Used as triggers to execute the instructions having those
- * variables as input. Leaving bits active to inhibit instruction execution.
- * Scheme used to make instruction disabling and automatic dependency fall-back
- * automatic.
- */
-
-#define CONSUME_TOKENS(state, bits, notbits) \
- ((!(state & (notbits))) && (state & (bits)) == (bits))
-
-#define PRODUCE_TOKENS(state, bits) \
- state = state | (bits);
-
-#define CLEAR_TOKENS(state, bits) \
- state = state & ~(bits)
-
-/*
- * Types of dependency :
- *
- * Data dependency
- *
- * - True dependency, Read-after-Write (RAW)
- *
- * This type of dependency happens when a statement depends on the result of a
- * previous statement. This applies to any statement which needs to read a
- * variable written by a preceding statement.
- *
- * - False dependency, Write-after-Read (WAR)
- *
- * Typically, variable renaming can ensure that this dependency goes away.
- * However, if the statements must read and then write from/to the same variable
- * in the OOO memory model, renaming may be impossible, and therefore this
- * causes a WAR dependency.
- *
- * - Output dependency, Write-after-Write (WAW)
- *
- * Two writes to the same variable in subsequent statements. Variable renaming
- * can ensure this is not needed, but can be required when writing multiple
- * times to the same OOO mem model variable.
- *
- * Control dependency
- *
- * Execution of a given instruction depends on a previous instruction evaluating
- * in a way that allows its execution. E.g. : branches.
- *
- * Useful considerations for joining dependencies after branch
- *
- * - Pre-dominance
- *
- * "We say box i dominates box j if every path (leading from input to output
- * through the diagram) which passes through box j must also pass through box
- * i. Thus box i dominates box j if box j is subordinate to box i in the
- * program."
- *
- * http://www.hipersoft.rice.edu/grads/publications/dom14.pdf
- * Other classic algorithm to calculate dominance : Lengauer-Tarjan (in gcc)
- *
- * - Post-dominance
- *
- * Just as pre-dominance, but with arcs of the data flow inverted, and input vs
- * output exchanged. Therefore, i post-dominating j ensures that every path
- * passing by j will pass by i before reaching the output.
- *
- * Prefetch and speculative execution
- *
- * If an instruction depends on the result of a previous branch, but it does not
- * have side-effects, it can be executed before the branch result is known.
- * however, it must be restarted if a core-synchronizing instruction is issued.
- * Note that instructions which depend on the speculative instruction result
- * but that have side-effects must depend on the branch completion in addition
- * to the speculatively executed instruction.
- *
- * Other considerations
- *
- * Note about "volatile" keyword dependency : The compiler will order volatile
- * accesses so they appear in the right order on a given CPU. They can be
- * reordered by the CPU instruction scheduling. This therefore cannot be
- * considered as a depencency.
- *
- * References :
- *
- * Cooper, Keith D.; & Torczon, Linda. (2005). Engineering a Compiler. Morgan
- * Kaufmann. ISBN 1-55860-698-X.
- * Kennedy, Ken; & Allen, Randy. (2001). Optimizing Compilers for Modern
- * Architectures: A Dependence-based Approach. Morgan Kaufmann. ISBN
- * 1-55860-286-0.
- * Muchnick, Steven S. (1997). Advanced Compiler Design and Implementation.
- * Morgan Kaufmann. ISBN 1-55860-320-4.
- */
-
-/*
- * Note about loops and nested calls
- *
- * To keep this model simple, loops expressed in the framework will behave as if
- * there was a core synchronizing instruction between loops. To see the effect
- * of loop unrolling, manually unrolling loops is required. Note that if loops
- * end or start with a core synchronizing instruction, the model is appropriate.
- * Nested calls are not supported.
- */
-
-/*
- * Only Alpha has out-of-order cache bank loads. Other architectures (intel,
- * powerpc, arm) ensure that dependent reads won't be reordered. c.f.
- * http://www.linuxjournal.com/article/8212)
- */
-#ifdef ARCH_ALPHA
-#define HAVE_OOO_CACHE_READ
-#endif
-
-/*
- * Each process have its own data in cache. Caches are randomly updated.
- * smp_wmb and smp_rmb forces cache updates (write and read), smp_mb forces
- * both.
- */
-
-typedef per_proc_byte {
- byte val[NR_PROCS];
-};
-
-typedef per_proc_bit {
- bit val[NR_PROCS];
-};
-
-/* Bitfield has a maximum of 8 procs */
-typedef per_proc_bitfield {
- byte bitfield;
-};
-
-#define DECLARE_CACHED_VAR(type, x) \
- type mem_##x;
-
-#define DECLARE_PROC_CACHED_VAR(type, x)\
- type cached_##x; \
- bit cache_dirty_##x;
-
-#define INIT_CACHED_VAR(x, v) \
- mem_##x = v;
-
-#define INIT_PROC_CACHED_VAR(x, v) \
- cache_dirty_##x = 0; \
- cached_##x = v;
-
-#define IS_CACHE_DIRTY(x, id) (cache_dirty_##x)
-
-#define READ_CACHED_VAR(x) (cached_##x)
-
-#define WRITE_CACHED_VAR(x, v) \
- atomic { \
- cached_##x = v; \
- cache_dirty_##x = 1; \
- }
-
-#define CACHE_WRITE_TO_MEM(x, id) \
- if \
- :: IS_CACHE_DIRTY(x, id) -> \
- mem_##x = cached_##x; \
- cache_dirty_##x = 0; \
- :: else -> \
- skip \
- fi;
-
-#define CACHE_READ_FROM_MEM(x, id) \
- if \
- :: !IS_CACHE_DIRTY(x, id) -> \
- cached_##x = mem_##x; \
- :: else -> \
- skip \
- fi;
-
-/*
- * May update other caches if cache is dirty, or not.
- */
-#define RANDOM_CACHE_WRITE_TO_MEM(x, id)\
- if \
- :: 1 -> CACHE_WRITE_TO_MEM(x, id); \
- :: 1 -> skip \
- fi;
-
-#define RANDOM_CACHE_READ_FROM_MEM(x, id)\
- if \
- :: 1 -> CACHE_READ_FROM_MEM(x, id); \
- :: 1 -> skip \
- fi;
-
-/* Must consume all prior read tokens. All subsequent reads depend on it. */
-inline smp_rmb(i)
-{
- atomic {
- CACHE_READ_FROM_MEM(urcu_gp_ctr, get_pid());
- i = 0;
- do
- :: i < NR_READERS ->
- CACHE_READ_FROM_MEM(urcu_active_readers[i], get_pid());
- i++
- :: i >= NR_READERS -> break
- od;
- CACHE_READ_FROM_MEM(rcu_ptr, get_pid());
- i = 0;
- do
- :: i < SLAB_SIZE ->
- CACHE_READ_FROM_MEM(rcu_data[i], get_pid());
- i++
- :: i >= SLAB_SIZE -> break
- od;
- }
-}
-
-/* Must consume all prior write tokens. All subsequent writes depend on it. */
-inline smp_wmb(i)
-{
- atomic {
- CACHE_WRITE_TO_MEM(urcu_gp_ctr, get_pid());
- i = 0;
- do
- :: i < NR_READERS ->
- CACHE_WRITE_TO_MEM(urcu_active_readers[i], get_pid());
- i++
- :: i >= NR_READERS -> break
- od;
- CACHE_WRITE_TO_MEM(rcu_ptr, get_pid());
- i = 0;
- do
- :: i < SLAB_SIZE ->
- CACHE_WRITE_TO_MEM(rcu_data[i], get_pid());
- i++
- :: i >= SLAB_SIZE -> break
- od;
- }
-}
-
-/* Synchronization point. Must consume all prior read and write tokens. All
- * subsequent reads and writes depend on it. */
-inline smp_mb(i)
-{
- atomic {
- smp_wmb(i);
- smp_rmb(i);
- }
-}
-
-#ifdef REMOTE_BARRIERS
-
-bit reader_barrier[NR_READERS];
-
-/*
- * We cannot leave the barriers dependencies in place in REMOTE_BARRIERS mode
- * because they would add unexisting core synchronization and would therefore
- * create an incomplete model.
- * Therefore, we model the read-side memory barriers by completely disabling the
- * memory barriers and their dependencies from the read-side. One at a time
- * (different verification runs), we make a different instruction listen for
- * signals.
- */
-
-#define smp_mb_reader(i, j)
-
-/*
- * Service 0, 1 or many barrier requests.
- */
-inline smp_mb_recv(i, j)
-{
- do
- :: (reader_barrier[get_readerid()] == 1) ->
- /*
- * We choose to ignore cycles caused by writer busy-looping,
- * waiting for the reader, sending barrier requests, and the
- * reader always services them without continuing execution.
- */
-progress_ignoring_mb1:
- smp_mb(i);
- reader_barrier[get_readerid()] = 0;
- :: 1 ->
- /*
- * We choose to ignore writer's non-progress caused by the
- * reader ignoring the writer's mb() requests.
- */
-progress_ignoring_mb2:
- break;
- od;
-}
-
-#define PROGRESS_LABEL(progressid) progress_writer_progid_##progressid:
-
-#define smp_mb_send(i, j, progressid) \
-{ \
- smp_mb(i); \
- i = 0; \
- do \
- :: i < NR_READERS -> \
- reader_barrier[i] = 1; \
- /* \
- * Busy-looping waiting for reader barrier handling is of little\
- * interest, given the reader has the ability to totally ignore \
- * barrier requests. \
- */ \
- do \
- :: (reader_barrier[i] == 1) -> \
-PROGRESS_LABEL(progressid) \
- skip; \
- :: (reader_barrier[i] == 0) -> break; \
- od; \
- i++; \
- :: i >= NR_READERS -> \
- break \
- od; \
- smp_mb(i); \
-}
-
-#else
-
-#define smp_mb_send(i, j, progressid) smp_mb(i)
-#define smp_mb_reader(i, j) smp_mb(i)
-#define smp_mb_recv(i, j)
-
-#endif
-
-/* Keep in sync manually with smp_rmb, smp_wmb, ooo_mem and init() */
-DECLARE_CACHED_VAR(byte, urcu_gp_ctr);
-/* Note ! currently only one reader */
-DECLARE_CACHED_VAR(byte, urcu_active_readers[NR_READERS]);
-/* RCU data */
-DECLARE_CACHED_VAR(bit, rcu_data[SLAB_SIZE]);
-
-/* RCU pointer */
-#if (SLAB_SIZE == 2)
-DECLARE_CACHED_VAR(bit, rcu_ptr);
-bit ptr_read_first[NR_READERS];
-bit ptr_read_second[NR_READERS];
-#else
-DECLARE_CACHED_VAR(byte, rcu_ptr);
-byte ptr_read_first[NR_READERS];
-byte ptr_read_second[NR_READERS];
-#endif
-
-bit data_read_first[NR_READERS];
-bit data_read_second[NR_READERS];
-
-bit init_done = 0;
-
-inline wait_init_done()
-{
- do
- :: init_done == 0 -> skip;
- :: else -> break;
- od;
-}
-
-inline ooo_mem(i)
-{
- atomic {
- RANDOM_CACHE_WRITE_TO_MEM(urcu_gp_ctr, get_pid());
- i = 0;
- do
- :: i < NR_READERS ->
- RANDOM_CACHE_WRITE_TO_MEM(urcu_active_readers[i],
- get_pid());
- i++
- :: i >= NR_READERS -> break
- od;
- RANDOM_CACHE_WRITE_TO_MEM(rcu_ptr, get_pid());
- i = 0;
- do
- :: i < SLAB_SIZE ->
- RANDOM_CACHE_WRITE_TO_MEM(rcu_data[i], get_pid());
- i++
- :: i >= SLAB_SIZE -> break
- od;
-#ifdef HAVE_OOO_CACHE_READ
- RANDOM_CACHE_READ_FROM_MEM(urcu_gp_ctr, get_pid());
- i = 0;
- do
- :: i < NR_READERS ->
- RANDOM_CACHE_READ_FROM_MEM(urcu_active_readers[i],
- get_pid());
- i++
- :: i >= NR_READERS -> break
- od;
- RANDOM_CACHE_READ_FROM_MEM(rcu_ptr, get_pid());
- i = 0;
- do
- :: i < SLAB_SIZE ->
- RANDOM_CACHE_READ_FROM_MEM(rcu_data[i], get_pid());
- i++
- :: i >= SLAB_SIZE -> break
- od;
-#else
- smp_rmb(i);
-#endif /* HAVE_OOO_CACHE_READ */
- }
-}
-
-/*
- * Bit encoding, urcu_reader :
- */
-
-int _proc_urcu_reader;
-#define proc_urcu_reader _proc_urcu_reader
-
-/* Body of PROCEDURE_READ_LOCK */
-#define READ_PROD_A_READ (1 << 0)
-#define READ_PROD_B_IF_TRUE (1 << 1)
-#define READ_PROD_B_IF_FALSE (1 << 2)
-#define READ_PROD_C_IF_TRUE_READ (1 << 3)
-
-#define PROCEDURE_READ_LOCK(base, consumetoken, consumetoken2, producetoken) \
- :: CONSUME_TOKENS(proc_urcu_reader, (consumetoken | consumetoken2), READ_PROD_A_READ << base) -> \
- ooo_mem(i); \
- tmp = READ_CACHED_VAR(urcu_active_readers[get_readerid()]); \
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROD_A_READ << base); \
- :: CONSUME_TOKENS(proc_urcu_reader, \
- READ_PROD_A_READ << base, /* RAW, pre-dominant */ \
- (READ_PROD_B_IF_TRUE | READ_PROD_B_IF_FALSE) << base) -> \
- if \
- :: (!(tmp & RCU_GP_CTR_NEST_MASK)) -> \
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROD_B_IF_TRUE << base); \
- :: else -> \
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROD_B_IF_FALSE << base); \
- fi; \
- /* IF TRUE */ \
- :: CONSUME_TOKENS(proc_urcu_reader, consumetoken, /* prefetch */ \
- READ_PROD_C_IF_TRUE_READ << base) -> \
- ooo_mem(i); \
- tmp2 = READ_CACHED_VAR(urcu_gp_ctr); \
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROD_C_IF_TRUE_READ << base); \
- :: CONSUME_TOKENS(proc_urcu_reader, \
- (READ_PROD_B_IF_TRUE \
- | READ_PROD_C_IF_TRUE_READ /* pre-dominant */ \
- | READ_PROD_A_READ) << base, /* WAR */ \
- producetoken) -> \
- ooo_mem(i); \
- WRITE_CACHED_VAR(urcu_active_readers[get_readerid()], tmp2); \
- PRODUCE_TOKENS(proc_urcu_reader, producetoken); \
- /* IF_MERGE implies \
- * post-dominance */ \
- /* ELSE */ \
- :: CONSUME_TOKENS(proc_urcu_reader, \
- (READ_PROD_B_IF_FALSE /* pre-dominant */ \
- | READ_PROD_A_READ) << base, /* WAR */ \
- producetoken) -> \
- ooo_mem(i); \
- WRITE_CACHED_VAR(urcu_active_readers[get_readerid()], \
- tmp + 1); \
- PRODUCE_TOKENS(proc_urcu_reader, producetoken); \
- /* IF_MERGE implies \
- * post-dominance */ \
- /* ENDIF */ \
- skip
-
-/* Body of PROCEDURE_READ_LOCK */
-#define READ_PROC_READ_UNLOCK (1 << 0)
-
-#define PROCEDURE_READ_UNLOCK(base, consumetoken, producetoken) \
- :: CONSUME_TOKENS(proc_urcu_reader, \
- consumetoken, \
- READ_PROC_READ_UNLOCK << base) -> \
- ooo_mem(i); \
- tmp = READ_CACHED_VAR(urcu_active_readers[get_readerid()]); \
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_READ_UNLOCK << base); \
- :: CONSUME_TOKENS(proc_urcu_reader, \
- consumetoken \
- | (READ_PROC_READ_UNLOCK << base), /* WAR */ \
- producetoken) -> \
- ooo_mem(i); \
- WRITE_CACHED_VAR(urcu_active_readers[get_readerid()], tmp - 1); \
- PRODUCE_TOKENS(proc_urcu_reader, producetoken); \
- skip
-
-
-#define READ_PROD_NONE (1 << 0)
-
-/* PROCEDURE_READ_LOCK base = << 1 : 1 to 5 */
-#define READ_LOCK_BASE 1
-#define READ_LOCK_OUT (1 << 5)
-
-#define READ_PROC_FIRST_MB (1 << 6)
-
-/* PROCEDURE_READ_LOCK (NESTED) base : << 7 : 7 to 11 */
-#define READ_LOCK_NESTED_BASE 7
-#define READ_LOCK_NESTED_OUT (1 << 11)
-
-#define READ_PROC_READ_GEN (1 << 12)
-#define READ_PROC_ACCESS_GEN (1 << 13)
-
-/* PROCEDURE_READ_UNLOCK (NESTED) base = << 14 : 14 to 15 */
-#define READ_UNLOCK_NESTED_BASE 14
-#define READ_UNLOCK_NESTED_OUT (1 << 15)
-
-#define READ_PROC_SECOND_MB (1 << 16)
-
-/* PROCEDURE_READ_UNLOCK base = << 17 : 17 to 18 */
-#define READ_UNLOCK_BASE 17
-#define READ_UNLOCK_OUT (1 << 18)
-
-/* PROCEDURE_READ_LOCK_UNROLL base = << 19 : 19 to 23 */
-#define READ_LOCK_UNROLL_BASE 19
-#define READ_LOCK_OUT_UNROLL (1 << 23)
-
-#define READ_PROC_THIRD_MB (1 << 24)
-
-#define READ_PROC_READ_GEN_UNROLL (1 << 25)
-#define READ_PROC_ACCESS_GEN_UNROLL (1 << 26)
-
-#define READ_PROC_FOURTH_MB (1 << 27)
-
-/* PROCEDURE_READ_UNLOCK_UNROLL base = << 28 : 28 to 29 */
-#define READ_UNLOCK_UNROLL_BASE 28
-#define READ_UNLOCK_OUT_UNROLL (1 << 29)
-
-
-/* Should not include branches */
-#define READ_PROC_ALL_TOKENS (READ_PROD_NONE \
- | READ_LOCK_OUT \
- | READ_PROC_FIRST_MB \
- | READ_LOCK_NESTED_OUT \
- | READ_PROC_READ_GEN \
- | READ_PROC_ACCESS_GEN \
- | READ_UNLOCK_NESTED_OUT \
- | READ_PROC_SECOND_MB \
- | READ_UNLOCK_OUT \
- | READ_LOCK_OUT_UNROLL \
- | READ_PROC_THIRD_MB \
- | READ_PROC_READ_GEN_UNROLL \
- | READ_PROC_ACCESS_GEN_UNROLL \
- | READ_PROC_FOURTH_MB \
- | READ_UNLOCK_OUT_UNROLL)
-
-/* Must clear all tokens, including branches */
-#define READ_PROC_ALL_TOKENS_CLEAR ((1 << 30) - 1)
-
-inline urcu_one_read(i, j, nest_i, tmp, tmp2)
-{
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROD_NONE);
-
-#ifdef NO_MB
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FIRST_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_SECOND_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_THIRD_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FOURTH_MB);
-#endif
-
-#ifdef REMOTE_BARRIERS
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FIRST_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_SECOND_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_THIRD_MB);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FOURTH_MB);
-#endif
-
- do
- :: 1 ->
-
-#ifdef REMOTE_BARRIERS
- /*
- * Signal-based memory barrier will only execute when the
- * execution order appears in program order.
- */
- if
- :: 1 ->
- atomic {
- if
- :: CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE,
- READ_LOCK_OUT | READ_LOCK_NESTED_OUT
- | READ_PROC_READ_GEN | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT,
- READ_LOCK_NESTED_OUT
- | READ_PROC_READ_GEN | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT | READ_LOCK_NESTED_OUT,
- READ_PROC_READ_GEN | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN,
- READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN | READ_PROC_ACCESS_GEN,
- READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN
- | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT,
- READ_UNLOCK_OUT
- | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN
- | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT,
- READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN
- | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT | READ_LOCK_OUT_UNROLL,
- READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN
- | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL,
- READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN
- | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL,
- READ_UNLOCK_OUT_UNROLL)
- || CONSUME_TOKENS(proc_urcu_reader, READ_PROD_NONE | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT | READ_PROC_READ_GEN | READ_PROC_ACCESS_GEN | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT | READ_LOCK_OUT_UNROLL
- | READ_PROC_READ_GEN_UNROLL | READ_PROC_ACCESS_GEN_UNROLL | READ_UNLOCK_OUT_UNROLL,
- 0) ->
- goto non_atomic3;
-non_atomic3_end:
- skip;
- fi;
- }
- fi;
-
- goto non_atomic3_skip;
-non_atomic3:
- smp_mb_recv(i, j);
- goto non_atomic3_end;
-non_atomic3_skip:
-
-#endif /* REMOTE_BARRIERS */
-
- atomic {
- if
- PROCEDURE_READ_LOCK(READ_LOCK_BASE, READ_PROD_NONE, 0, READ_LOCK_OUT);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_LOCK_OUT, /* post-dominant */
- READ_PROC_FIRST_MB) ->
- smp_mb_reader(i, j);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FIRST_MB);
-
- PROCEDURE_READ_LOCK(READ_LOCK_NESTED_BASE, READ_PROC_FIRST_MB, READ_LOCK_OUT,
- READ_LOCK_NESTED_OUT);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_FIRST_MB, /* mb() orders reads */
- READ_PROC_READ_GEN) ->
- ooo_mem(i);
- ptr_read_first[get_readerid()] = READ_CACHED_VAR(rcu_ptr);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_READ_GEN);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_FIRST_MB /* mb() orders reads */
- | READ_PROC_READ_GEN,
- READ_PROC_ACCESS_GEN) ->
- /* smp_read_barrier_depends */
- goto rmb1;
-rmb1_end:
- data_read_first[get_readerid()] =
- READ_CACHED_VAR(rcu_data[ptr_read_first[get_readerid()]]);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_ACCESS_GEN);
-
-
- /* Note : we remove the nested memory barrier from the read unlock
- * model, given it is not usually needed. The implementation has the barrier
- * because the performance impact added by a branch in the common case does not
- * justify it.
- */
-
- PROCEDURE_READ_UNLOCK(READ_UNLOCK_NESTED_BASE,
- READ_PROC_FIRST_MB
- | READ_LOCK_OUT
- | READ_LOCK_NESTED_OUT,
- READ_UNLOCK_NESTED_OUT);
-
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_ACCESS_GEN /* mb() orders reads */
- | READ_PROC_READ_GEN /* mb() orders reads */
- | READ_PROC_FIRST_MB /* mb() ordered */
- | READ_LOCK_OUT /* post-dominant */
- | READ_LOCK_NESTED_OUT /* post-dominant */
- | READ_UNLOCK_NESTED_OUT,
- READ_PROC_SECOND_MB) ->
- smp_mb_reader(i, j);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_SECOND_MB);
-
- PROCEDURE_READ_UNLOCK(READ_UNLOCK_BASE,
- READ_PROC_SECOND_MB /* mb() orders reads */
- | READ_PROC_FIRST_MB /* mb() orders reads */
- | READ_LOCK_NESTED_OUT /* RAW */
- | READ_LOCK_OUT /* RAW */
- | READ_UNLOCK_NESTED_OUT, /* RAW */
- READ_UNLOCK_OUT);
-
- /* Unrolling loop : second consecutive lock */
- /* reading urcu_active_readers, which have been written by
- * READ_UNLOCK_OUT : RAW */
- PROCEDURE_READ_LOCK(READ_LOCK_UNROLL_BASE,
- READ_PROC_SECOND_MB /* mb() orders reads */
- | READ_PROC_FIRST_MB, /* mb() orders reads */
- READ_LOCK_NESTED_OUT /* RAW */
- | READ_LOCK_OUT /* RAW */
- | READ_UNLOCK_NESTED_OUT /* RAW */
- | READ_UNLOCK_OUT, /* RAW */
- READ_LOCK_OUT_UNROLL);
-
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_FIRST_MB /* mb() ordered */
- | READ_PROC_SECOND_MB /* mb() ordered */
- | READ_LOCK_OUT_UNROLL /* post-dominant */
- | READ_LOCK_NESTED_OUT
- | READ_LOCK_OUT
- | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT,
- READ_PROC_THIRD_MB) ->
- smp_mb_reader(i, j);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_THIRD_MB);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_FIRST_MB /* mb() orders reads */
- | READ_PROC_SECOND_MB /* mb() orders reads */
- | READ_PROC_THIRD_MB, /* mb() orders reads */
- READ_PROC_READ_GEN_UNROLL) ->
- ooo_mem(i);
- ptr_read_second[get_readerid()] = READ_CACHED_VAR(rcu_ptr);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_READ_GEN_UNROLL);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_READ_GEN_UNROLL
- | READ_PROC_FIRST_MB /* mb() orders reads */
- | READ_PROC_SECOND_MB /* mb() orders reads */
- | READ_PROC_THIRD_MB, /* mb() orders reads */
- READ_PROC_ACCESS_GEN_UNROLL) ->
- /* smp_read_barrier_depends */
- goto rmb2;
-rmb2_end:
- data_read_second[get_readerid()] =
- READ_CACHED_VAR(rcu_data[ptr_read_second[get_readerid()]]);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_ACCESS_GEN_UNROLL);
-
- :: CONSUME_TOKENS(proc_urcu_reader,
- READ_PROC_READ_GEN_UNROLL /* mb() orders reads */
- | READ_PROC_ACCESS_GEN_UNROLL /* mb() orders reads */
- | READ_PROC_FIRST_MB /* mb() ordered */
- | READ_PROC_SECOND_MB /* mb() ordered */
- | READ_PROC_THIRD_MB /* mb() ordered */
- | READ_LOCK_OUT_UNROLL /* post-dominant */
- | READ_LOCK_NESTED_OUT
- | READ_LOCK_OUT
- | READ_UNLOCK_NESTED_OUT
- | READ_UNLOCK_OUT,
- READ_PROC_FOURTH_MB) ->
- smp_mb_reader(i, j);
- PRODUCE_TOKENS(proc_urcu_reader, READ_PROC_FOURTH_MB);
-
- PROCEDURE_READ_UNLOCK(READ_UNLOCK_UNROLL_BASE,
- READ_PROC_FOURTH_MB /* mb() orders reads */
- | READ_PROC_THIRD_MB /* mb() orders reads */
- | READ_LOCK_OUT_UNROLL /* RAW */
- | READ_PROC_SECOND_MB /* mb() orders reads */
- | READ_PROC_FIRST_MB /* mb() orders reads */
- | READ_LOCK_NESTED_OUT /* RAW */
- | READ_LOCK_OUT /* RAW */
- | READ_UNLOCK_NESTED_OUT, /* RAW */
- READ_UNLOCK_OUT_UNROLL);
- :: CONSUME_TOKENS(proc_urcu_reader, READ_PROC_ALL_TOKENS, 0) ->
- CLEAR_TOKENS(proc_urcu_reader, READ_PROC_ALL_TOKENS_CLEAR);
- break;
- fi;
- }
- od;
- /*
- * Dependency between consecutive loops :
- * RAW dependency on
- * WRITE_CACHED_VAR(urcu_active_readers[get_readerid()], tmp2 - 1)
- * tmp = READ_CACHED_VAR(urcu_active_readers[get_readerid()]);
- * between loops.
- * _WHEN THE MB()s are in place_, they add full ordering of the
- * generation pointer read wrt active reader count read, which ensures
- * execution will not spill across loop execution.
- * However, in the event mb()s are removed (execution using signal
- * handler to promote barrier()() -> smp_mb()), nothing prevents one loop
- * to spill its execution on other loop's execution.
- */
- goto end;
-rmb1:
-#ifndef NO_RMB
- smp_rmb(i);
-#else
- ooo_mem(i);
-#endif
- goto rmb1_end;
-rmb2:
-#ifndef NO_RMB
- smp_rmb(i);
-#else
- ooo_mem(i);
-#endif
- goto rmb2_end;
-end:
- skip;
-}
-
-
-
-active proctype urcu_reader()
-{
- byte i, j, nest_i;
- byte tmp, tmp2;
-
- /* Keep in sync manually with smp_rmb, smp_wmb, ooo_mem and init() */
- DECLARE_PROC_CACHED_VAR(byte, urcu_gp_ctr);
- /* Note ! currently only one reader */
- DECLARE_PROC_CACHED_VAR(byte, urcu_active_readers[NR_READERS]);
- /* RCU data */
- DECLARE_PROC_CACHED_VAR(bit, rcu_data[SLAB_SIZE]);
-
- /* RCU pointer */
-#if (SLAB_SIZE == 2)
- DECLARE_PROC_CACHED_VAR(bit, rcu_ptr);
-#else
- DECLARE_PROC_CACHED_VAR(byte, rcu_ptr);
-#endif
-
- atomic {
- INIT_PROC_CACHED_VAR(urcu_gp_ctr, 1);
- INIT_PROC_CACHED_VAR(rcu_ptr, 0);
-
- i = 0;
- do
- :: i < NR_READERS ->
- INIT_PROC_CACHED_VAR(urcu_active_readers[i], 0);
- i++;
- :: i >= NR_READERS -> break
- od;
- INIT_PROC_CACHED_VAR(rcu_data[0], WINE);
- i = 1;
- do
- :: i < SLAB_SIZE ->
- INIT_PROC_CACHED_VAR(rcu_data[i], POISON);
- i++
- :: i >= SLAB_SIZE -> break
- od;
- }
-
- wait_init_done();
-
- assert(get_pid() < NR_PROCS);
-
-end_reader:
- do
- :: 1 ->
- /*
- * We do not test reader's progress here, because we are mainly
- * interested in writer's progress. The reader never blocks
- * anyway. We have to test for reader/writer's progress
- * separately, otherwise we could think the writer is doing
- * progress when it's blocked by an always progressing reader.
- */
-#ifdef READER_PROGRESS
-progress_reader:
-#endif
- urcu_one_read(i, j, nest_i, tmp, tmp2);
- od;
-}
-
-/* no name clash please */
-#undef proc_urcu_reader
-
-
-/* Model the RCU update process. */
-
-/*
- * Bit encoding, urcu_writer :
- * Currently only supports one reader.
- */
-
-int _proc_urcu_writer;
-#define proc_urcu_writer _proc_urcu_writer
-
-#define WRITE_PROD_NONE (1 << 0)
-
-#define WRITE_DATA (1 << 1)
-#define WRITE_PROC_WMB (1 << 2)
-#define WRITE_XCHG_PTR (1 << 3)
-
-#define WRITE_PROC_FIRST_MB (1 << 4)
-
-/* first flip */
-#define WRITE_PROC_FIRST_READ_GP (1 << 5)
-#define WRITE_PROC_FIRST_WRITE_GP (1 << 6)
-#define WRITE_PROC_FIRST_WAIT (1 << 7)
-#define WRITE_PROC_FIRST_WAIT_LOOP (1 << 8)
-
-/* second flip */
-#define WRITE_PROC_SECOND_READ_GP (1 << 9)
-#define WRITE_PROC_SECOND_WRITE_GP (1 << 10)
-#define WRITE_PROC_SECOND_WAIT (1 << 11)
-#define WRITE_PROC_SECOND_WAIT_LOOP (1 << 12)
-
-#define WRITE_PROC_SECOND_MB (1 << 13)
-
-#define WRITE_FREE (1 << 14)
-
-#define WRITE_PROC_ALL_TOKENS (WRITE_PROD_NONE \
- | WRITE_DATA \
- | WRITE_PROC_WMB \
- | WRITE_XCHG_PTR \
- | WRITE_PROC_FIRST_MB \
- | WRITE_PROC_FIRST_READ_GP \
- | WRITE_PROC_FIRST_WRITE_GP \
- | WRITE_PROC_FIRST_WAIT \
- | WRITE_PROC_SECOND_READ_GP \
- | WRITE_PROC_SECOND_WRITE_GP \
- | WRITE_PROC_SECOND_WAIT \
- | WRITE_PROC_SECOND_MB \
- | WRITE_FREE)
-
-#define WRITE_PROC_ALL_TOKENS_CLEAR ((1 << 15) - 1)
-
-/*
- * Mutexes are implied around writer execution. A single writer at a time.
- */
-active proctype urcu_writer()
-{
- byte i, j;
- byte tmp, tmp2, tmpa;
- byte cur_data = 0, old_data, loop_nr = 0;
- byte cur_gp_val = 0; /*
- * Keep a local trace of the current parity so
- * we don't add non-existing dependencies on the global
- * GP update. Needed to test single flip case.
- */
-
- /* Keep in sync manually with smp_rmb, smp_wmb, ooo_mem and init() */
- DECLARE_PROC_CACHED_VAR(byte, urcu_gp_ctr);
- /* Note ! currently only one reader */
- DECLARE_PROC_CACHED_VAR(byte, urcu_active_readers[NR_READERS]);
- /* RCU data */
- DECLARE_PROC_CACHED_VAR(bit, rcu_data[SLAB_SIZE]);
-
- /* RCU pointer */
-#if (SLAB_SIZE == 2)
- DECLARE_PROC_CACHED_VAR(bit, rcu_ptr);
-#else
- DECLARE_PROC_CACHED_VAR(byte, rcu_ptr);
-#endif
-
- atomic {
- INIT_PROC_CACHED_VAR(urcu_gp_ctr, 1);
- INIT_PROC_CACHED_VAR(rcu_ptr, 0);
-
- i = 0;
- do
- :: i < NR_READERS ->
- INIT_PROC_CACHED_VAR(urcu_active_readers[i], 0);
- i++;
- :: i >= NR_READERS -> break
- od;
- INIT_PROC_CACHED_VAR(rcu_data[0], WINE);
- i = 1;
- do
- :: i < SLAB_SIZE ->
- INIT_PROC_CACHED_VAR(rcu_data[i], POISON);
- i++
- :: i >= SLAB_SIZE -> break
- od;
- }
-
-
- wait_init_done();
-
- assert(get_pid() < NR_PROCS);
-
- do
- :: (loop_nr < 3) ->
-#ifdef WRITER_PROGRESS
-progress_writer1:
-#endif
- loop_nr = loop_nr + 1;
-
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROD_NONE);
-
-#ifdef NO_WMB
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_WMB);
-#endif
-
-#ifdef NO_MB
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_MB);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_MB);
-#endif
-
-#ifdef SINGLE_FLIP
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_READ_GP);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WRITE_GP);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT);
- /* For single flip, we need to know the current parity */
- cur_gp_val = cur_gp_val ^ RCU_GP_CTR_BIT;
-#endif
-
- do :: 1 ->
- atomic {
- if
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROD_NONE,
- WRITE_DATA) ->
- ooo_mem(i);
- cur_data = (cur_data + 1) % SLAB_SIZE;
- WRITE_CACHED_VAR(rcu_data[cur_data], WINE);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_DATA);
-
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_DATA,
- WRITE_PROC_WMB) ->
- smp_wmb(i);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_WMB);
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROC_WMB,
- WRITE_XCHG_PTR) ->
- /* rcu_xchg_pointer() */
- atomic {
- old_data = READ_CACHED_VAR(rcu_ptr);
- WRITE_CACHED_VAR(rcu_ptr, cur_data);
- }
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_XCHG_PTR);
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_DATA | WRITE_PROC_WMB | WRITE_XCHG_PTR,
- WRITE_PROC_FIRST_MB) ->
- goto smp_mb_send1;
-smp_mb_send1_end:
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_MB);
-
- /* first flip */
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROC_FIRST_MB,
- WRITE_PROC_FIRST_READ_GP) ->
- tmpa = READ_CACHED_VAR(urcu_gp_ctr);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_READ_GP);
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROC_FIRST_MB | WRITE_PROC_WMB
- | WRITE_PROC_FIRST_READ_GP,
- WRITE_PROC_FIRST_WRITE_GP) ->
- ooo_mem(i);
- WRITE_CACHED_VAR(urcu_gp_ctr, tmpa ^ RCU_GP_CTR_BIT);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WRITE_GP);
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- //WRITE_PROC_FIRST_WRITE_GP | /* TEST ADDING SYNC CORE */
- WRITE_PROC_FIRST_MB, /* can be reordered before/after flips */
- WRITE_PROC_FIRST_WAIT | WRITE_PROC_FIRST_WAIT_LOOP) ->
- ooo_mem(i);
- //smp_mb(i); /* TEST */
- /* ONLY WAITING FOR READER 0 */
- tmp2 = READ_CACHED_VAR(urcu_active_readers[0]);
-#ifndef SINGLE_FLIP
- /* In normal execution, we are always starting by
- * waiting for the even parity.
- */
- cur_gp_val = RCU_GP_CTR_BIT;
-#endif
- if
- :: (tmp2 & RCU_GP_CTR_NEST_MASK)
- && ((tmp2 ^ cur_gp_val) & RCU_GP_CTR_BIT) ->
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WAIT_LOOP);
- :: else ->
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WAIT);
- fi;
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- //WRITE_PROC_FIRST_WRITE_GP /* TEST ADDING SYNC CORE */
- WRITE_PROC_FIRST_WRITE_GP
- | WRITE_PROC_FIRST_READ_GP
- | WRITE_PROC_FIRST_WAIT_LOOP
- | WRITE_DATA | WRITE_PROC_WMB | WRITE_XCHG_PTR
- | WRITE_PROC_FIRST_MB, /* can be reordered before/after flips */
- 0) ->
-#ifndef GEN_ERROR_WRITER_PROGRESS
- goto smp_mb_send2;
-smp_mb_send2_end:
- /* The memory barrier will invalidate the
- * second read done as prefetching. Note that all
- * instructions with side-effects depending on
- * WRITE_PROC_SECOND_READ_GP should also depend on
- * completion of this busy-waiting loop. */
- CLEAR_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_READ_GP);
-#else
- ooo_mem(i);
-#endif
- /* This instruction loops to WRITE_PROC_FIRST_WAIT */
- CLEAR_TOKENS(proc_urcu_writer, WRITE_PROC_FIRST_WAIT_LOOP | WRITE_PROC_FIRST_WAIT);
-
- /* second flip */
- :: CONSUME_TOKENS(proc_urcu_writer,
- //WRITE_PROC_FIRST_WAIT | //test /* no dependency. Could pre-fetch, no side-effect. */
- WRITE_PROC_FIRST_WRITE_GP
- | WRITE_PROC_FIRST_READ_GP
- | WRITE_PROC_FIRST_MB,
- WRITE_PROC_SECOND_READ_GP) ->
- ooo_mem(i);
- //smp_mb(i); /* TEST */
- tmpa = READ_CACHED_VAR(urcu_gp_ctr);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_READ_GP);
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROC_FIRST_WAIT /* dependency on first wait, because this
- * instruction has globally observable
- * side-effects.
- */
- | WRITE_PROC_FIRST_MB
- | WRITE_PROC_WMB
- | WRITE_PROC_FIRST_READ_GP
- | WRITE_PROC_FIRST_WRITE_GP
- | WRITE_PROC_SECOND_READ_GP,
- WRITE_PROC_SECOND_WRITE_GP) ->
- ooo_mem(i);
- WRITE_CACHED_VAR(urcu_gp_ctr, tmpa ^ RCU_GP_CTR_BIT);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WRITE_GP);
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- //WRITE_PROC_FIRST_WRITE_GP | /* TEST ADDING SYNC CORE */
- WRITE_PROC_FIRST_WAIT
- | WRITE_PROC_FIRST_MB, /* can be reordered before/after flips */
- WRITE_PROC_SECOND_WAIT | WRITE_PROC_SECOND_WAIT_LOOP) ->
- ooo_mem(i);
- //smp_mb(i); /* TEST */
- /* ONLY WAITING FOR READER 0 */
- tmp2 = READ_CACHED_VAR(urcu_active_readers[0]);
- if
- :: (tmp2 & RCU_GP_CTR_NEST_MASK)
- && ((tmp2 ^ 0) & RCU_GP_CTR_BIT) ->
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT_LOOP);
- :: else ->
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT);
- fi;
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- //WRITE_PROC_FIRST_WRITE_GP | /* TEST ADDING SYNC CORE */
- WRITE_PROC_SECOND_WRITE_GP
- | WRITE_PROC_FIRST_WRITE_GP
- | WRITE_PROC_SECOND_READ_GP
- | WRITE_PROC_FIRST_READ_GP
- | WRITE_PROC_SECOND_WAIT_LOOP
- | WRITE_DATA | WRITE_PROC_WMB | WRITE_XCHG_PTR
- | WRITE_PROC_FIRST_MB, /* can be reordered before/after flips */
- 0) ->
-#ifndef GEN_ERROR_WRITER_PROGRESS
- goto smp_mb_send3;
-smp_mb_send3_end:
-#else
- ooo_mem(i);
-#endif
- /* This instruction loops to WRITE_PROC_SECOND_WAIT */
- CLEAR_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_WAIT_LOOP | WRITE_PROC_SECOND_WAIT);
-
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_PROC_FIRST_WAIT
- | WRITE_PROC_SECOND_WAIT
- | WRITE_PROC_FIRST_READ_GP
- | WRITE_PROC_SECOND_READ_GP
- | WRITE_PROC_FIRST_WRITE_GP
- | WRITE_PROC_SECOND_WRITE_GP
- | WRITE_DATA | WRITE_PROC_WMB | WRITE_XCHG_PTR
- | WRITE_PROC_FIRST_MB,
- WRITE_PROC_SECOND_MB) ->
- goto smp_mb_send4;
-smp_mb_send4_end:
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_PROC_SECOND_MB);
-
- :: CONSUME_TOKENS(proc_urcu_writer,
- WRITE_XCHG_PTR
- | WRITE_PROC_FIRST_WAIT
- | WRITE_PROC_SECOND_WAIT
- | WRITE_PROC_WMB /* No dependency on
- * WRITE_DATA because we
- * write to a
- * different location. */
- | WRITE_PROC_SECOND_MB
- | WRITE_PROC_FIRST_MB,
- WRITE_FREE) ->
- WRITE_CACHED_VAR(rcu_data[old_data], POISON);
- PRODUCE_TOKENS(proc_urcu_writer, WRITE_FREE);
-
- :: CONSUME_TOKENS(proc_urcu_writer, WRITE_PROC_ALL_TOKENS, 0) ->
- CLEAR_TOKENS(proc_urcu_writer, WRITE_PROC_ALL_TOKENS_CLEAR);
- break;
- fi;
- }
- od;
- /*
- * Note : Promela model adds implicit serialization of the
- * WRITE_FREE instruction. Normally, it would be permitted to
- * spill on the next loop execution. Given the validation we do
- * checks for the data entry read to be poisoned, it's ok if
- * we do not check "late arriving" memory poisoning.
- */
- :: else -> break;
- od;
- /*
- * Given the reader loops infinitely, let the writer also busy-loop
- * with progress here so, with weak fairness, we can test the
- * writer's progress.
- */
-end_writer:
- do
- :: 1 ->
-#ifdef WRITER_PROGRESS
-progress_writer2:
-#endif
-#ifdef READER_PROGRESS
- /*
- * Make sure we don't block the reader's progress.
- */
- smp_mb_send(i, j, 5);
-#endif
- skip;
- od;
-
- /* Non-atomic parts of the loop */
- goto end;
-smp_mb_send1:
- smp_mb_send(i, j, 1);
- goto smp_mb_send1_end;
-#ifndef GEN_ERROR_WRITER_PROGRESS
-smp_mb_send2:
- smp_mb_send(i, j, 2);
- goto smp_mb_send2_end;
-smp_mb_send3:
- smp_mb_send(i, j, 3);
- goto smp_mb_send3_end;
-#endif
-smp_mb_send4:
- smp_mb_send(i, j, 4);
- goto smp_mb_send4_end;
-end:
- skip;
-}
-
-/* no name clash please */
-#undef proc_urcu_writer
-
-
-/* Leave after the readers and writers so the pid count is ok. */
-init {
- byte i, j;
-
- atomic {
- INIT_CACHED_VAR(urcu_gp_ctr, 1);
- INIT_CACHED_VAR(rcu_ptr, 0);
-
- i = 0;
- do
- :: i < NR_READERS ->
- INIT_CACHED_VAR(urcu_active_readers[i], 0);
- ptr_read_first[i] = 1;
- ptr_read_second[i] = 1;
- data_read_first[i] = WINE;
- data_read_second[i] = WINE;
- i++;
- :: i >= NR_READERS -> break
- od;
- INIT_CACHED_VAR(rcu_data[0], WINE);
- i = 1;
- do
- :: i < SLAB_SIZE ->
- INIT_CACHED_VAR(rcu_data[i], POISON);
- i++
- :: i >= SLAB_SIZE -> break
- od;
-
- init_done = 1;
- }
-}