diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/core/lib/support/stack_lockfree.cc | 137 | ||||
-rw-r--r-- | src/core/lib/support/stack_lockfree.h | 46 | ||||
-rw-r--r-- | src/python/grpcio/grpc_core_dependencies.py | 1 |
3 files changed, 0 insertions, 184 deletions
diff --git a/src/core/lib/support/stack_lockfree.cc b/src/core/lib/support/stack_lockfree.cc deleted file mode 100644 index 7a4ede3b92..0000000000 --- a/src/core/lib/support/stack_lockfree.cc +++ /dev/null @@ -1,137 +0,0 @@ -/* - * - * Copyright 2015 gRPC authors. - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - */ - -#include "src/core/lib/support/stack_lockfree.h" - -#include <stdlib.h> -#include <string.h> - -#include <grpc/support/alloc.h> -#include <grpc/support/atm.h> -#include <grpc/support/log.h> -#include <grpc/support/port_platform.h> - -/* The lockfree node structure is a single architecture-level - word that allows for an atomic CAS to set it up. */ -struct lockfree_node_contents { - /* next thing to look at. Actual index for head, next index otherwise */ - uint16_t index; -#ifdef GPR_ARCH_64 - uint16_t pad; - uint32_t aba_ctr; -#else -#ifdef GPR_ARCH_32 - uint16_t aba_ctr; -#else -#error Unsupported bit width architecture -#endif -#endif -}; - -/* Use a union to make sure that these are in the same bits as an atm word */ -typedef union lockfree_node { - gpr_atm atm; - struct lockfree_node_contents contents; -} lockfree_node; - -/* make sure that entries aligned to 8-bytes */ -#define ENTRY_ALIGNMENT_BITS 3 -/* reserve this entry as invalid */ -#define INVALID_ENTRY_INDEX ((1 << 16) - 1) - -struct gpr_stack_lockfree { - lockfree_node* entries; - lockfree_node head; /* An atomic entry describing curr head */ -}; - -gpr_stack_lockfree* gpr_stack_lockfree_create(size_t entries) { - gpr_stack_lockfree* stack; - stack = (gpr_stack_lockfree*)gpr_malloc(sizeof(*stack)); - /* Since we only allocate 16 bits to represent an entry number, - * make sure that we are within the desired range */ - /* Reserve the highest entry number as a dummy */ - GPR_ASSERT(entries < INVALID_ENTRY_INDEX); - stack->entries = (lockfree_node*)gpr_malloc_aligned( - entries * sizeof(stack->entries[0]), ENTRY_ALIGNMENT_BITS); - /* Clear out all entries */ - memset(stack->entries, 0, entries * sizeof(stack->entries[0])); - memset(&stack->head, 0, sizeof(stack->head)); - - GPR_ASSERT(sizeof(stack->entries->atm) == sizeof(stack->entries->contents)); - - /* Point the head at reserved dummy entry */ - stack->head.contents.index = INVALID_ENTRY_INDEX; -/* Fill in the pad and aba_ctr to avoid confusing memcheck tools */ -#ifdef GPR_ARCH_64 - stack->head.contents.pad = 0; -#endif - stack->head.contents.aba_ctr = 0; - return stack; -} - -void gpr_stack_lockfree_destroy(gpr_stack_lockfree* stack) { - gpr_free_aligned(stack->entries); - gpr_free(stack); -} - -int gpr_stack_lockfree_push(gpr_stack_lockfree* stack, int entry) { - lockfree_node head; - lockfree_node newhead; - lockfree_node curent; - lockfree_node newent; - - /* First fill in the entry's index and aba ctr for new head */ - newhead.contents.index = (uint16_t)entry; -#ifdef GPR_ARCH_64 - /* Fill in the pad to avoid confusing memcheck tools */ - newhead.contents.pad = 0; -#endif - - /* Also post-increment the aba_ctr */ - curent.atm = gpr_atm_no_barrier_load(&stack->entries[entry].atm); - newhead.contents.aba_ctr = ++curent.contents.aba_ctr; - gpr_atm_no_barrier_store(&stack->entries[entry].atm, curent.atm); - - do { - /* Atomically get the existing head value for use */ - head.atm = gpr_atm_no_barrier_load(&(stack->head.atm)); - /* Point to it */ - newent.atm = gpr_atm_no_barrier_load(&stack->entries[entry].atm); - newent.contents.index = head.contents.index; - gpr_atm_no_barrier_store(&stack->entries[entry].atm, newent.atm); - } while (!gpr_atm_rel_cas(&(stack->head.atm), head.atm, newhead.atm)); - /* Use rel_cas above to make sure that entry index is set properly */ - return head.contents.index == INVALID_ENTRY_INDEX; -} - -int gpr_stack_lockfree_pop(gpr_stack_lockfree* stack) { - lockfree_node head; - lockfree_node newhead; - - do { - head.atm = gpr_atm_acq_load(&(stack->head.atm)); - if (head.contents.index == INVALID_ENTRY_INDEX) { - return -1; - } - newhead.atm = - gpr_atm_no_barrier_load(&(stack->entries[head.contents.index].atm)); - - } while (!gpr_atm_no_barrier_cas(&(stack->head.atm), head.atm, newhead.atm)); - - return head.contents.index; -} diff --git a/src/core/lib/support/stack_lockfree.h b/src/core/lib/support/stack_lockfree.h deleted file mode 100644 index 337ecc2b17..0000000000 --- a/src/core/lib/support/stack_lockfree.h +++ /dev/null @@ -1,46 +0,0 @@ -/* - * - * Copyright 2015 gRPC authors. - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - */ - -#ifndef GRPC_CORE_LIB_SUPPORT_STACK_LOCKFREE_H -#define GRPC_CORE_LIB_SUPPORT_STACK_LOCKFREE_H - -#include <stddef.h> - -#ifdef __cplusplus -extern "C" { -#endif - -typedef struct gpr_stack_lockfree gpr_stack_lockfree; - -/* This stack must specify the maximum number of entries to track. - The current implementation only allows up to 65534 entries */ -gpr_stack_lockfree* gpr_stack_lockfree_create(size_t entries); -void gpr_stack_lockfree_destroy(gpr_stack_lockfree* stack); - -/* Pass in a valid entry number for the next stack entry */ -/* Returns 1 if this is the first element on the stack, 0 otherwise */ -int gpr_stack_lockfree_push(gpr_stack_lockfree*, int entry); - -/* Returns -1 on empty or the actual entry number */ -int gpr_stack_lockfree_pop(gpr_stack_lockfree* stack); - -#ifdef __cplusplus -} -#endif - -#endif /* GRPC_CORE_LIB_SUPPORT_STACK_LOCKFREE_H */ diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py index 330c4185c6..efb4d8617d 100644 --- a/src/python/grpcio/grpc_core_dependencies.py +++ b/src/python/grpcio/grpc_core_dependencies.py @@ -38,7 +38,6 @@ CORE_SOURCE_FILES = [ 'src/core/lib/support/log_windows.cc', 'src/core/lib/support/mpscq.cc', 'src/core/lib/support/murmur_hash.cc', - 'src/core/lib/support/stack_lockfree.cc', 'src/core/lib/support/string.cc', 'src/core/lib/support/string_posix.cc', 'src/core/lib/support/string_util_windows.cc', |