--- /dev/null
+#define WRITER_PROGRESS
+
+// Poison value for freed memory
+#define POISON 1
+// Memory with correct data
+#define WINE 0
+#define SLAB_SIZE 2
+
+#define read_poison (data_read_first[0] == POISON || data_read_second[0] == POISON)
+
+#define RCU_GP_CTR_BIT (1 << 7)
+#define RCU_GP_CTR_NEST_MASK (RCU_GP_CTR_BIT - 1)
+
+//disabled
+#define REMOTE_BARRIERS
+
+#define ARCH_ALPHA
+//#define ARCH_INTEL
+//#define ARCH_POWERPC
+/*
+ * 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;
+ }
+}
projects / urcu.git / blobdiff