diff options
Diffstat (limited to 'erts/emulator')
| -rw-r--r-- | erts/emulator/Makefile.in | 6 | ||||
| -rw-r--r-- | erts/emulator/nifs/common/prim_buffer_nif.c | 512 |
2 files changed, 516 insertions, 2 deletions
diff --git a/erts/emulator/Makefile.in b/erts/emulator/Makefile.in index fdaf253fe5..9a09a0f6fa 100644 --- a/erts/emulator/Makefile.in +++ b/erts/emulator/Makefile.in @@ -644,7 +644,8 @@ PRELOAD_BEAM = $(ERL_TOP)/erts/preloaded/ebin/otp_ring0.beam \ $(ERL_TOP)/erts/preloaded/ebin/erts_internal.beam \ $(ERL_TOP)/erts/preloaded/ebin/erl_tracer.beam \ $(ERL_TOP)/erts/preloaded/ebin/erts_literal_area_collector.beam \ - $(ERL_TOP)/erts/preloaded/ebin/erts_dirty_process_code_checker.beam + $(ERL_TOP)/erts/preloaded/ebin/erts_dirty_process_code_checker.beam \ + $(ERL_TOP)/erts/preloaded/ebin/prim_buffer.beam ifeq ($(TARGET),win32) # On windows the preloaded objects are in a resource object. @@ -873,7 +874,8 @@ RUN_OBJS += \ LTTNG_OBJS = $(OBJDIR)/erlang_lttng.o NIF_OBJS = \ $(OBJDIR)/erl_tracer_nif.o \ - $(OBJDIR)/zlib_nif.o + $(OBJDIR)/zlib_nif.o \ + $(OBJDIR)/prim_buffer_nif.o ifeq ($(TARGET),win32) DRV_OBJS = \ diff --git a/erts/emulator/nifs/common/prim_buffer_nif.c b/erts/emulator/nifs/common/prim_buffer_nif.c new file mode 100644 index 0000000000..a8ef5fc355 --- /dev/null +++ b/erts/emulator/nifs/common/prim_buffer_nif.c @@ -0,0 +1,512 @@ +/* + * %CopyrightBegin% + * + * Copyright Ericsson 2017. All Rights Reserved. + * + * 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. + * + * %CopyrightEnd% + */ + +#define STATIC_ERLANG_NIF 1 + +#include "erl_nif.h" +#include "config.h" +#include "sys.h" + +#ifdef VALGRIND +# include <valgrind/memcheck.h> +#endif + +#define ACCUMULATOR_SIZE (2 << 10) + +#define FIND_NIF_RESCHEDULE_SIZE (1 << 20) + +/* NIF interface declarations */ +static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info); +static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info); +static void unload(ErlNifEnv *env, void* priv_data); + +static ErlNifResourceType *rtype_buffer; + +static ERL_NIF_TERM am_ok; +static ERL_NIF_TERM am_error; + +static ERL_NIF_TERM am_lock_order_violation; + +static ERL_NIF_TERM am_acquired; +static ERL_NIF_TERM am_busy; + +static ERL_NIF_TERM am_continue; + +static ERL_NIF_TERM am_out_of_memory; +static ERL_NIF_TERM am_not_found; + +typedef struct { +#ifdef DEBUG + erts_atomic32_t concurrent_users; +#endif + + ErlNifBinary accumulator; + size_t accumulated_bytes; + int accumulator_present; + + ErlNifIOQueue *queue; + + erts_atomic32_t external_lock; +} buffer_data_t; + +static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); + +static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); +static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); +static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); + +static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); +static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); + +static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); + +static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); +static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]); + +static ErlNifFunc nif_funcs[] = { + {"new", 0, new_nif}, + {"size", 1, size_nif}, + {"peek_head", 1, peek_head_nif}, + {"copying_read", 2, copying_read_nif}, + {"write", 2, write_nif}, + {"skip", 2, skip_nif}, + {"find_byte_index", 2, find_nif}, + {"try_lock", 1, trylock_nif}, + {"unlock", 1, unlock_nif}, +}; + +ERL_NIF_INIT(prim_buffer, nif_funcs, load, NULL, upgrade, unload) + +static void gc_buffer(ErlNifEnv *env, void* data); + +static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info) +{ + am_ok = enif_make_atom(env, "ok"); + am_error = enif_make_atom(env, "error"); + + am_lock_order_violation = enif_make_atom(env, "lock_order_violation"); + am_acquired = enif_make_atom(env, "acquired"); + am_busy = enif_make_atom(env, "busy"); + + am_continue = enif_make_atom(env, "continue"); + + am_out_of_memory = enif_make_atom(env, "out_of_memory"); + am_not_found = enif_make_atom(env, "not_found"); + + rtype_buffer = enif_open_resource_type(env, NULL, "gc_buffer", gc_buffer, + ERL_NIF_RT_CREATE, NULL); + + *priv_data = NULL; + + return 0; +} + +static void unload(ErlNifEnv *env, void* priv_data) +{ + +} + +static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info) +{ + if(*old_priv_data != NULL) { + return -1; /* Don't know how to do that */ + } + + if(*priv_data != NULL) { + return -1; /* Don't know how to do that */ + } + + if(load(env, priv_data, load_info)) { + return -1; + } + + return 0; +} + +static void gc_buffer(ErlNifEnv *env, void* data) { + buffer_data_t *buffer = (buffer_data_t*)data; + + if(buffer->accumulator_present) { + enif_release_binary(&buffer->accumulator); + } + + enif_ioq_destroy(buffer->queue); +} + +static int get_buffer_data(ErlNifEnv *env, ERL_NIF_TERM opaque, buffer_data_t **buffer) { + return enif_get_resource(env, opaque, rtype_buffer, (void **)buffer); +} + +/* Copies a number of bytes from the head of the iovec, skipping "vec_skip" + * vector elements followed by "byte_skip" bytes on the target vector. */ +static void copy_from_iovec(SysIOVec *iovec, int vec_len, int vec_skip, + size_t byte_skip, size_t size, char *data) { + + size_t bytes_copied, skip_offset; + int vec_index; + + skip_offset = byte_skip; + vec_index = vec_skip; + bytes_copied = 0; + + while(bytes_copied < size) { + size_t block_size, copy_size; + char *block_start; + + ASSERT(vec_index < vec_len); + + block_start = (char*)iovec[vec_index].iov_base; + block_size = iovec[vec_index].iov_len; + + copy_size = MIN(size - bytes_copied, block_size - skip_offset); + sys_memcpy(&data[bytes_copied], &block_start[skip_offset], copy_size); + + bytes_copied += copy_size; + skip_offset = 0; + + vec_index++; + } +} + +/* Convenience function for copy_from_iovec over queues. */ +static void copy_from_queue(ErlNifIOQueue *queue, int queue_skip, + size_t byte_skip, size_t size, char *data) { + + SysIOVec *queued_data; + int queue_length; + + queued_data = enif_ioq_peek(queue, &queue_length); + ASSERT(queue_skip < queue_length); + + copy_from_iovec(queued_data, queue_length, queue_skip, byte_skip, size, data); +} + +static int enqueue_write_accumulator(buffer_data_t *buffer) { + ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0)); + + if(buffer->accumulator_present && buffer->accumulated_bytes > 0) { + if(!enif_realloc_binary(&buffer->accumulator, buffer->accumulated_bytes)) { + return 0; + } else if(!enif_ioq_enq_binary(buffer->queue, &buffer->accumulator, 0)) { + return 0; + } + + /* The queue owns the accumulator now. */ + buffer->accumulator_present = 0; + buffer->accumulated_bytes = 0; + } + + return 1; +} + +static int combine_small_writes(buffer_data_t *buffer, ErlNifIOVec *iovec) { + ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0)); + + if(buffer->accumulated_bytes + iovec->size >= ACCUMULATOR_SIZE) { + if(iovec->size >= (ACCUMULATOR_SIZE / 2)) { + return 0; + } + + if(!enqueue_write_accumulator(buffer)) { + return 0; + } + } + + if(!buffer->accumulator_present) { + if(!enif_alloc_binary(ACCUMULATOR_SIZE, &buffer->accumulator)) { + return 0; + } + + buffer->accumulator_present = 1; + } + + copy_from_iovec(iovec->iov, iovec->iovcnt, 0, 0, iovec->size, + (char*)&buffer->accumulator.data[buffer->accumulated_bytes]); + buffer->accumulated_bytes += iovec->size; + + return 1; +} + +/* *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** */ + +static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + ERL_NIF_TERM result; + + buffer = (buffer_data_t*)enif_alloc_resource(rtype_buffer, sizeof(buffer_data_t)); + buffer->queue = enif_ioq_create(ERL_NIF_IOQ_NORMAL); + + if(buffer->queue != NULL) { +#ifdef DEBUG + erts_atomic32_init_nob(&buffer->concurrent_users, 0); +#endif + erts_atomic32_init_nob(&buffer->external_lock, 0); + + buffer->accumulator_present = 0; + buffer->accumulated_bytes = 0; + + result = enif_make_resource(env, buffer); + } else { + result = enif_raise_exception(env, am_out_of_memory); + } + + enif_release_resource(buffer); + + return result; +} + +static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + size_t total_size; + + if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + total_size = enif_ioq_size(buffer->queue); + + if(buffer->accumulator_present) { + total_size += buffer->accumulated_bytes; + } else { + ASSERT(buffer->accumulated_bytes == 0); + } + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return enif_make_uint64(env, total_size); +} + +static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + ERL_NIF_TERM result; + unsigned char *data; + Uint64 block_size; + + if(argc != 2 || !get_buffer_data(env, argv[0], &buffer) + || !enif_get_uint64(env, argv[1], &block_size)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + if(!enqueue_write_accumulator(buffer)) { + return enif_raise_exception(env, am_out_of_memory); + } + + if(enif_ioq_size(buffer->queue) < block_size) { + return enif_make_badarg(env); + } + + data = enif_make_new_binary(env, block_size, &result); + + if(block_size > 0) { + copy_from_queue(buffer->queue, 0, 0, block_size, (char*)data); + enif_ioq_deq(buffer->queue, block_size, NULL); + } + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return result; +} + +static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + ErlNifIOVec vec, *iovec = &vec; + ERL_NIF_TERM tail; + + if(argc != 2 || !get_buffer_data(env, argv[0], &buffer) + || !enif_inspect_iovec(env, 64, argv[1], &tail, &iovec)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + if(!combine_small_writes(buffer, iovec)) { + if(!enqueue_write_accumulator(buffer) || !enif_ioq_enqv(buffer->queue, iovec, 0)) { + return enif_raise_exception(env, am_out_of_memory); + } + } + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + if(!enif_is_empty_list(env, tail)) { + const ERL_NIF_TERM new_argv[2] = {argv[0], tail}; + + return enif_schedule_nif(env, "write", 0, &write_nif, argc, new_argv); + } + + return am_ok; +} + +static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + ERL_NIF_TERM result; + + if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + if(!enqueue_write_accumulator(buffer)) { + return enif_raise_exception(env, am_out_of_memory); + } + + if(!enif_ioq_peek_head(env, buffer->queue, NULL, &result)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return result; +} + +static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + Uint64 block_size; + + if(argc != 2 || !get_buffer_data(env, argv[0], &buffer) + || !enif_get_uint64(env, argv[1], &block_size)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + if(!enqueue_write_accumulator(buffer)) { + return enif_raise_exception(env, am_out_of_memory); + } else if(enif_ioq_size(buffer->queue) < block_size) { + return enif_make_badarg(env); + } + + enif_ioq_deq(buffer->queue, block_size, NULL); + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return am_ok; +} + +static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + int queue_length, queue_index; + SysIOVec *queued_data; + size_t queue_size; + + size_t search_offset; + int needle; + + if(argc != 2 || !get_buffer_data(env, argv[0], &buffer) + || !enif_get_int(env, argv[1], &needle)) { + return enif_make_badarg(env); + } + + ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1); + + if(!enqueue_write_accumulator(buffer)) { + return enif_raise_exception(env, am_out_of_memory); + } else if(needle < 0 || needle > 255) { + return enif_make_badarg(env); + } + + queued_data = enif_ioq_peek(buffer->queue, &queue_length); + queue_size = enif_ioq_size(buffer->queue); + queue_index = 0; + + search_offset = 0; + + if(queue_size > (FIND_NIF_RESCHEDULE_SIZE / 100)) { + if(enif_thread_type() == ERL_NIF_THR_NORMAL_SCHEDULER) { + int timeslice_percent; + + if(queue_size >= FIND_NIF_RESCHEDULE_SIZE) { + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return enif_schedule_nif(env, "find", + ERL_NIF_DIRTY_JOB_CPU_BOUND, &find_nif, argc, argv); + } + + timeslice_percent = (queue_size * 100) / FIND_NIF_RESCHEDULE_SIZE; + enif_consume_timeslice(env, timeslice_percent); + } + } + + while(queue_index < queue_length) { + char *needle_address; + char *block_start; + size_t block_size; + + block_start = queued_data[queue_index].iov_base; + block_size = queued_data[queue_index].iov_len; + + needle_address = memchr(block_start, needle, block_size); + + if(needle_address != NULL) { + size_t result = search_offset + (needle_address - block_start); + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return enif_make_tuple2(env, am_ok, enif_make_uint64(env, result)); + } + + search_offset += block_size; + queue_index++; + } + + ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0); + + return am_not_found; +} + +/* */ + +static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) { + return enif_make_badarg(env); + } + + if(erts_atomic32_cmpxchg_acqb(&buffer->external_lock, 1, 0) == 0) { + return am_acquired; + } + + return am_busy; +} + +static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { + buffer_data_t *buffer; + + if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) { + return enif_make_badarg(env); + } + + if(erts_atomic32_cmpxchg_relb(&buffer->external_lock, 0, 1) == 0) { + return enif_raise_exception(env, am_lock_order_violation); + } + + return am_ok; +} |