/* * MARS Long Distance Replication Software * * This file is part of MARS project: http://schoebel.github.io/mars/ * * Copyright (C) 2010-2014 Thomas Schoebel-Theuer * Copyright (C) 2011-2014 1&1 Internet AG * * 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., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ // Copy brick (just for demonstration) //#define BRICK_DEBUGGING //#define MARS_DEBUGGING //#define IO_DEBUGGING #include #include #include #include "mars.h" #include "lib_limiter.h" #ifndef READ #define READ 0 #define WRITE 1 #endif #define COPY_CHUNK (PAGE_SIZE) #define NR_COPY_REQUESTS (128 * 1024 * 1024 / COPY_CHUNK) #define STATES_PER_PAGE (PAGE_SIZE / sizeof(struct copy_state)) #define MAX_SUB_TABLES (NR_COPY_REQUESTS / STATES_PER_PAGE + (NR_COPY_REQUESTS % STATES_PER_PAGE ? 1 : 0)) #define MAX_COPY_REQUESTS (PAGE_SIZE / sizeof(struct copy_state*) * STATES_PER_PAGE) #define GET_STATE(brick,index) \ ((brick)->st[(index) / STATES_PER_PAGE][(index) % STATES_PER_PAGE]) ///////////////////////// own type definitions //////////////////////// #include "mars_copy.h" int mars_copy_overlap = 1; EXPORT_SYMBOL_GPL(mars_copy_overlap); /* Always leave at 1, disable only for throughput _testing_ */ int mars_copy_strict_write_order = 1; int mars_copy_timeout = 180; int mars_copy_read_prio = MARS_PRIO_NORMAL; EXPORT_SYMBOL_GPL(mars_copy_read_prio); int mars_copy_write_prio = MARS_PRIO_NORMAL; EXPORT_SYMBOL_GPL(mars_copy_write_prio); int mars_copy_read_max_fly = 32768; EXPORT_SYMBOL_GPL(mars_copy_read_max_fly); int mars_copy_write_max_fly = 32768; EXPORT_SYMBOL_GPL(mars_copy_write_max_fly); atomic_t global_copy_read_flight; atomic_t global_copy_write_flight; #define is_read_limited(brick) \ (mars_copy_read_max_fly > 0 && atomic_read(&global_copy_read_flight) >= mars_copy_read_max_fly) #define is_write_limited(brick) \ (mars_copy_write_max_fly > 0 && atomic_read(&global_copy_write_flight) >= mars_copy_write_max_fly) ///////////////////////// own helper functions //////////////////////// /* TODO: * The clash logic is untested / alpha stage (Feb. 2011). * * For now, the output is never used, so this cannot do harm. * * In order to get the output really working / enterprise grade, * some larger test effort should be invested. */ static inline void _clash(struct copy_brick *brick) { brick->trigger = true; set_bit(0, &brick->clash); atomic_inc(&brick->total_clash_count); wake_up_interruptible(&brick->event); } static inline int _clear_clash(struct copy_brick *brick) { int old; old = test_and_clear_bit(0, &brick->clash); return old; } /* Current semantics: * * All writes are always going to the original input A. They are _not_ * replicated to B. * * In order to get B really uptodate, you have to replay the right * transaction logs there (at the right time). * [If you had no writes on A at all during the copy, of course * this is not necessary] * * When utilize_mode is on, reads can utilize the already copied * region from B, but only as long as this region has not been * invalidated by writes (indicated by low_dirty). * * TODO: implement replicated writes, together with some transaction * replay logic applying the transaction logs _only_ after * crashes during inconsistency caused by partial replication of writes. */ static int _determine_input(struct copy_brick *brick, struct mref_object *mref) { int below; int behind; loff_t ref_end; if (!brick->utilize_mode || brick->low_dirty) return INPUT_A_IO; ref_end = mref->ref_pos + mref->ref_len; below = ref_end <= brick->copy_start; behind = !brick->copy_end || mref->ref_pos >= brick->copy_end; if (mref->ref_flags & (MREF_WRITE | MREF_MAY_WRITE)) { if (!behind) { brick->low_dirty = true; if (!below) { _clash(brick); wake_up_interruptible(&brick->event); } } return INPUT_A_IO; } if (below) return INPUT_B_IO; return INPUT_A_IO; } #define GET_INDEX(pos) (((pos) / COPY_CHUNK) % NR_COPY_REQUESTS) #define GET_OFFSET(pos) ((pos) % COPY_CHUNK) static void __clear_mref(struct copy_brick *brick, struct mref_object *mref, int queue) { struct copy_input *input; input = queue ? brick->inputs[INPUT_B_COPY] : brick->inputs[INPUT_A_COPY]; GENERIC_INPUT_CALL(input, mref_put, mref); } static void _clear_mref(struct copy_brick *brick, int index, int queue) { struct copy_state *st = &GET_STATE(brick, index); struct mref_object *mref = st->table[queue]; if (mref) { if (unlikely(st->active[queue])) { MARS_ERR("clearing active mref, index = %d queue = %d\n", index, queue); st->active[queue] = false; } __clear_mref(brick, mref, queue); st->table[queue] = NULL; } } static void _clear_all_mref(struct copy_brick *brick) { int i; for (i = 0; i < NR_COPY_REQUESTS; i++) { GET_STATE(brick, i).state = COPY_STATE_START; _clear_mref(brick, i, 0); _clear_mref(brick, i, 1); } } static void _clear_state_table(struct copy_brick *brick) { int i; for (i = 0; i < MAX_SUB_TABLES; i++) { struct copy_state *sub_table = brick->st[i]; memset(sub_table, 0, PAGE_SIZE); } } static void copy_endio(struct generic_callback *cb) { struct copy_mref_aspect *mref_a; struct mref_object *mref; struct copy_input *input; struct copy_brick *brick; struct copy_state *st; int index; int queue; int error = 0; LAST_CALLBACK(cb); mref_a = cb->cb_private; CHECK_PTR(mref_a, err); mref = mref_a->object; CHECK_PTR(mref, err); brick = mref_a->brick; CHECK_PTR(brick, err); /* This is racy, but affects only a _hint_ for * performance optimization. */ input = mref_a->input; if (input && (!input->check_hint || mref->ref_pos < input->check_hint)) input->check_hint = mref->ref_pos; queue = mref_a->queue; index = GET_INDEX(mref->ref_pos); st = &GET_STATE(brick, index); MARS_IO("queue = %d index = %d pos = %lld status = %d\n", queue, index, mref->ref_pos, cb->cb_error); if (unlikely(queue < 0 || queue >= 2)) { MARS_ERR("bad queue %d\n", queue); error = -EINVAL; goto exit; } if (unlikely(st->table[queue] != mref)) { MARS_ERR("table corruption at %d %d (%p => %p)\n", index, queue, st->table[queue], mref); error = -EEXIST; goto exit; } if (unlikely(cb->cb_error < 0)) { error = cb->cb_error; /* This is racy, but does no harm. * Worst case just produces more error output. */ if (!brick->copy_error_count++) { MARS_WRN("IO error %d on index %d, old state = %d\n", cb->cb_error, index, st->state); } } exit: if (unlikely(error < 0)) { st->error = error; _clash(brick); } st->active[queue] = false; if (mref->ref_flags & MREF_WRITE) { atomic_dec(&brick->copy_write_flight); atomic_dec(&global_copy_write_flight); } else { atomic_dec(&brick->copy_read_flight); atomic_dec(&global_copy_read_flight); } brick->trigger = true; wake_up_interruptible(&brick->event); return; err: MARS_FAT("cannot handle callback\n"); } static int _make_mref(struct copy_brick *brick, int index, int queue, void *data, loff_t pos, loff_t end_pos, __u32 flags) { struct mref_object *mref; struct copy_mref_aspect *mref_a; struct copy_input *input; struct copy_state *st; int offset; int len; int status = -EAGAIN; if (brick->clash || end_pos <= 0) goto done; mref = copy_alloc_mref(brick); status = -ENOMEM; if (unlikely(!mref)) goto done; mref_a = copy_mref_get_aspect(brick, mref); if (unlikely(!mref_a)) { MARS_FAT("cannot get own apsect\n"); goto done; } mref_a->brick = brick; mref_a->queue = queue; mref->ref_flags = flags; mref->ref_data = data; mref->ref_pos = pos; offset = GET_OFFSET(pos); len = COPY_CHUNK - offset; if (pos + len > end_pos) { len = end_pos - pos; } mref->ref_len = len; mref->ref_prio = (flags & MREF_WRITE) ? mars_copy_write_prio : mars_copy_read_prio; if (mref->ref_prio < MARS_PRIO_HIGH || mref->ref_prio > MARS_PRIO_LOW) mref->ref_prio = brick->io_prio; SETUP_CALLBACK(mref, copy_endio, mref_a); input = queue ? brick->inputs[INPUT_B_COPY] : brick->inputs[INPUT_A_COPY]; mref_a->input = input; status = GENERIC_INPUT_CALL(input, mref_get, mref); if (unlikely(status < 0)) { MARS_ERR("status = %d\n", status); mars_free_mref(mref); goto done; } if (unlikely(mref->ref_len < len)) { MARS_DBG("shorten len %d < %d\n", mref->ref_len, len); } if (queue == 0) { GET_STATE(brick, index).len = mref->ref_len; } else if (unlikely(mref->ref_len < GET_STATE(brick, index).len)) { MARS_DBG("shorten len %d < %d at index %d\n", mref->ref_len, GET_STATE(brick, index).len, index); GET_STATE(brick, index).len = mref->ref_len; } st = &GET_STATE(brick, index); st->table[queue] = mref; st->active[queue] = true; if (flags & MREF_WRITE) { atomic_inc(&brick->copy_write_flight); atomic_inc(&global_copy_write_flight); } else { atomic_inc(&brick->copy_read_flight); atomic_inc(&global_copy_read_flight); } GENERIC_INPUT_CALL(input, mref_io, mref); done: return status; } static void _update_percent(struct copy_brick *brick, bool force) { if (force || brick->copy_last > brick->copy_start + 8 * 1024 * 1024 || (long long)jiffies > brick->last_jiffies + 5 * HZ || (brick->copy_last == brick->copy_end && brick->copy_end > 0)) { brick->copy_start = brick->copy_last; brick->last_jiffies = jiffies; brick->power.percent_done = brick->copy_end > 0 ? brick->copy_start * 100 / brick->copy_end : 0; MARS_INF("'%s' copied %lld / %lld bytes (%d%%)\n", brick->brick_path, brick->copy_last, brick->copy_end, brick->power.percent_done); } } static inline __u32 _make_flags(bool verify_mode) { if (!verify_mode) return 0; return MREF_NODATA | MREF_CHKSUM_ANY; } /* The heart of this brick. * State transition function of the finite automaton. * In case no progress is possible (e.g. preconditions not * yet true), the state is left as is (idempotence property: * calling this too often does no harm, just costs performance). */ static int _next_state(struct copy_brick *brick, int index, loff_t pos) { struct mref_object *mref0; struct mref_object *mref1; struct copy_state *st; char state; char next_state; bool do_restart = false; int progress = 0; int status; st = &GET_STATE(brick, index); next_state = st->state; restart: state = next_state; MARS_IO("ENTER index=%d state=%d pos=%lld table[0]=%p table[1]=%p active[0]=%d active[1]=%d writeout=%d prev=%d len=%d error=%d do_restart=%d\n", index, state, pos, st->table[0], st->table[1], st->active[0], st->active[1], st->writeout, st->prev, st->len, st->error, do_restart); do_restart = false; switch (state) { case COPY_STATE_RESET: /* This state is only entered after errors or * in restarting situations. */ _clear_mref(brick, index, 1); _clear_mref(brick, index, 0); next_state = COPY_STATE_START; /* fallthrough */ case COPY_STATE_START: /* This is the relgular starting state. * It must be zero, automatically entered via memset() */ if (st->table[0] || st->table[1]) { MARS_ERR("index %d not startable\n", index); progress = -EPROTO; goto idle; } st->writeout = false; st->error = 0; if (brick->is_aborting || is_read_limited(brick)) goto idle; status = _make_mref(brick, index, 0, NULL, pos, brick->copy_end, _make_flags(brick->verify_mode)); if (unlikely(status < 0)) { MARS_DBG("status = %d\n", status); progress = status; break; } next_state = COPY_STATE_READ1; if (!brick->verify_mode) { break; } next_state = COPY_STATE_START2; /* fallthrough */ case COPY_STATE_START2: status = _make_mref(brick, index, 1, NULL, pos, brick->copy_end, _make_flags(true)); if (unlikely(status < 0)) { MARS_DBG("status = %d\n", status); progress = status; break; } next_state = COPY_STATE_READ2; /* fallthrough */ case COPY_STATE_READ2: if (st->active[1]) { // idempotence: wait by unchanged state goto idle; } /* fallthrough => wait for both mrefs to appear */ case COPY_STATE_READ1: case COPY_STATE_READ3: if (st->active[0]) { // idempotence: wait by unchanged state goto idle; } mref0 = st->table[0]; if (brick->copy_limiter) { int amount = (mref0->ref_len - 1) / 1024 + 1; mars_limit_sleep(brick->copy_limiter, amount); } // on append mode: increase the end pointer dynamically if (brick->append_mode > 0 && mref0->ref_total_size && mref0->ref_total_size > brick->copy_end) { brick->copy_end = mref0->ref_total_size; } // do verify (when applicable) mref1 = st->table[1]; if (mref1 && state != COPY_STATE_READ3) { int len = mref0->ref_len; bool ok; if (len != mref1->ref_len) { ok = false; } else if (mref0->ref_flags & MREF_CHKSUM_ANY) { static unsigned char null[sizeof(mref0->ref_checksum)]; ok = !memcmp(mref0->ref_checksum, mref1->ref_checksum, sizeof(mref0->ref_checksum)); if (ok) ok = memcmp(mref0->ref_checksum, null, sizeof(mref0->ref_checksum)) != 0; } else if (!mref0->ref_data || !mref1->ref_data) { ok = false; } else { ok = !memcmp(mref0->ref_data, mref1->ref_data, len); } _clear_mref(brick, index, 1); if (ok) brick->verify_ok_count++; else brick->verify_error_count++; if (ok || !brick->repair_mode) { /* skip start of writing, goto final treatment of writeout */ next_state = COPY_STATE_CLEANUP; break; } } if ((mref0->ref_flags & MREF_CHKSUM_ANY) && (mref0->ref_flags & MREF_NODATA)) { /* re-read, this time with data */ _clear_mref(brick, index, 0); status = _make_mref(brick, index, 0, NULL, pos, brick->copy_end, _make_flags(false)); if (unlikely(status < 0)) { MARS_DBG("status = %d\n", status); progress = status; next_state = COPY_STATE_RESET; break; } next_state = COPY_STATE_READ3; break; } next_state = COPY_STATE_WRITE; /* fallthrough */ case COPY_STATE_WRITE: if (is_write_limited(brick)) goto idle; /* Obey ordering to get a strict "append" behaviour. * We assume that we don't need to wait for completion * of the previous write to avoid a sparse result file * under all circumstances, i.e. we only assure that * _starting_ the writes is in order. * This is only correct when all lower bricks obey the * order of ref_io() operations. * Currenty, bio and aio are obeying this. Be careful when * implementing new IO bricks! */ if (mars_copy_strict_write_order && st->prev >= 0 && !GET_STATE(brick, st->prev).writeout) { goto idle; } mref0 = st->table[0]; if (unlikely(!mref0 || !mref0->ref_data)) { MARS_ERR("src buffer for write does not exist, state %d at index %d\n", state, index); progress = -EILSEQ; break; } if (unlikely(st->active[0])) { MARS_ERR("src buffer for write is active, state %d at index %d\n", state, index); progress = -EILSEQ; break; } if (unlikely(brick->is_aborting)) { progress = -EINTR; break; } /* start writeout */ status = _make_mref(brick, index, 1, mref0->ref_data, pos, pos + mref0->ref_len, MREF_WRITE | MREF_MAY_WRITE); if (unlikely(status < 0)) { MARS_DBG("status = %d\n", status); progress = status; next_state = COPY_STATE_RESET; break; } /* Attention! overlapped IO behind EOF could * lead to temporary inconsistent state of the * file, because the write order may be different from * strict O_APPEND behaviour. */ if (mars_copy_overlap) st->writeout = true; next_state = COPY_STATE_WRITTEN; /* fallthrough */ case COPY_STATE_WRITTEN: if (st->active[1]) { // idempotence: wait by unchanged state MARS_IO("irrelevant\n"); goto idle; } st->writeout = true; /* rechecking means to start over again. * ATTENTIION! this may lead to infinite request * submission loops, intentionally. * TODO: implement some timeout means. */ if (brick->recheck_mode && brick->repair_mode) { next_state = COPY_STATE_RESET; break; } next_state = COPY_STATE_CLEANUP; /* fallthrough */ case COPY_STATE_CLEANUP: _clear_mref(brick, index, 1); _clear_mref(brick, index, 0); next_state = COPY_STATE_FINISHED; /* fallthrough */ case COPY_STATE_FINISHED: /* Indicate successful completion by remaining in this state. * Restart of the finite automaton must be done externally. */ goto idle; default: MARS_ERR("illegal state %d at index %d\n", state, index); _clash(brick); progress = -EILSEQ; } do_restart = (state != next_state); idle: if (unlikely(progress < 0)) { if (st->error >= 0) st->error = progress; MARS_DBG("progress = %d\n", progress); progress = 0; _clash(brick); } else if (do_restart) { goto restart; } else if (st->state != next_state) { progress++; } MARS_IO("LEAVE index=%d state=%d next_state=%d table[0]=%p table[1]=%p active[0]=%d active[1]=%d writeout=%d prev=%d len=%d error=%d progress=%d\n", index, st->state, next_state, st->table[0], st->table[1], st->active[0], st->active[1], st->writeout, st->prev, st->len, st->error, progress); // save the resulting state st->state = next_state; return progress; } static int _run_copy(struct copy_brick *brick, loff_t this_start) { int all_max; int max; loff_t pos; short prev; int progress; if (unlikely(_clear_clash(brick))) { MARS_DBG("clash\n"); if (atomic_read(&brick->copy_read_flight) + atomic_read(&brick->copy_write_flight) > 0) { /* wait until all pending copy IO has finished */ _clash(brick); MARS_DBG("re-clash\n"); brick_msleep(100); return 0; } _clear_all_mref(brick); _clear_state_table(brick); } if (this_start < brick->copy_last) this_start = brick->copy_last; else if (this_start > brick->copy_dirty && brick->copy_dirty) this_start = brick->copy_dirty; /* Do at most max iterations in the below loop */ max = NR_COPY_REQUESTS - 1 - atomic_read(&brick->io_flight) * 2; if (unlikely(max < 32)) max = 32; all_max = max; MARS_IO("max = %d\n", max); prev = -1; if (this_start > brick->copy_last) { prev = GET_INDEX(this_start - COPY_CHUNK); max -= (this_start - brick->copy_last) / COPY_CHUNK; all_max = max; } progress = 0; for (pos = this_start; pos < brick->copy_end || brick->append_mode > 1; pos = ((pos / COPY_CHUNK) + 1) * COPY_CHUNK) { int index = GET_INDEX(pos); struct copy_state *st = &GET_STATE(brick, index); int this_progress; if (max-- <= 0) { break; } st->prev = prev; prev = index; if (st->active[0] & st->active[1]) break; // call the finite state automaton this_progress = _next_state(brick, index, pos); if (this_progress <= 0) break; progress += this_progress; if (pos > brick->copy_dirty) brick->copy_dirty = pos; } // check the resulting state: can we advance the copy_last pointer? if (this_start == brick->copy_last && progress && !brick->clash) { int count = 0; max = all_max; for (pos = brick->copy_last; pos < brick->copy_end; pos = ((pos / COPY_CHUNK) + 1) * COPY_CHUNK) { int index = GET_INDEX(pos); struct copy_state *st = &GET_STATE(brick, index); if (st->state != COPY_STATE_FINISHED) { break; } if (max-- <= 0) { break; } if (unlikely(st->error < 0)) { /* check for fatal consistency errors */ if (st->error == -EMEDIUMTYPE) { brick->copy_error = st->error; brick->abort_mode = true; MARS_WRN("Consistency is violated\n"); } if (!brick->copy_error) { brick->copy_error = st->error; MARS_WRN("IO error = %d\n", st->error); } if (brick->abort_mode) { brick->is_aborting = true; } break; } // rollover st->state = COPY_STATE_START; count += st->len; // check contiguity if (unlikely(GET_OFFSET(pos) + st->len != COPY_CHUNK)) { /* Short read detected: shorten the copy_end. */ brick->copy_end = pos + st->len; break; } } if (count > 0) { brick->copy_last += count; get_lamport(NULL, &brick->copy_last_stamp); MARS_IO("new copy_last += %d => %lld\n", count, brick->copy_last); _update_percent(brick, false); } } return progress; } static bool _is_done(struct copy_brick *brick) { if (!brick->power.led_on || brick_thread_should_stop()) brick->is_aborting = true; return brick->is_aborting && atomic_read(&brick->copy_read_flight) + atomic_read(&brick->copy_write_flight) <= 0; } static int _copy_thread(void *data) { struct copy_brick *brick = data; struct lamport_time last_progress = get_real_lamport(); int i; MARS_DBG("--------------- copy_thread %p starting\n", brick); brick->copy_error = 0; brick->copy_error_count = 0; brick->verify_ok_count = 0; brick->verify_error_count = 0; for (i = 0; i < COPY_INPUT_NR; i++) brick->inputs[i]->check_hint = 0; if (brick->copy_limiter) mars_limit_reset(brick->copy_limiter); _update_percent(brick, true); brick->trigger = true; while (!_is_done(brick)) { loff_t old_start = brick->copy_start; loff_t old_end = brick->copy_end; int progress = 0; loff_t check_hint; if (old_end > 0) { loff_t old_last = brick->copy_last; loff_t old_dirty = brick->copy_dirty; progress = _run_copy(brick, -1); /* This is racy, deliberately. * Missing some events does no harm. */ for (i = 0; i < COPY_INPUT_NR; i++) { check_hint = brick->inputs[i]->check_hint; if (check_hint > 0) { brick->inputs[i]->check_hint = 0; progress += _run_copy(brick, check_hint); } } /* earlier resume working at the tail */ if (brick->copy_last > old_last && old_dirty) progress += _run_copy(brick, old_dirty); /* abort when no progress is made for a longer time */ if (progress > 0) { last_progress = get_real_lamport(); } else { struct lamport_time next_progress = get_real_lamport(); next_progress.tv_sec -= mars_copy_timeout; if (lamport_time_compare(&next_progress, &last_progress) > 0) brick->is_aborting = true; } } wait_event_interruptible_timeout(brick->event, progress > 0 || brick->trigger || brick->copy_start != old_start || brick->copy_end != old_end || _is_done(brick), 1 * HZ); brick->trigger = false; } if (brick->copy_limiter) mars_limit_reset(brick->copy_limiter); /* check for fatal consistency errors */ if (brick->copy_error == -EMEDIUMTYPE) { /* reset the whole area */ brick->copy_start = 0; brick->copy_last = 0; brick->copy_dirty = 0; MARS_WRN("resetting the full copy area\n"); } _update_percent(brick, true); MARS_DBG("--------------- copy_thread terminating (%d read requests / %d write requests flying, copy_start = %lld copy_end = %lld)\n", atomic_read(&brick->copy_read_flight), atomic_read(&brick->copy_write_flight), brick->copy_start, brick->copy_end); _clear_all_mref(brick); brick->terminated = true; mars_trigger(); MARS_DBG("--------------- copy_thread done.\n"); return 0; } ////////////////// own brick / input / output operations ////////////////// static int copy_get_info(struct copy_output *output, struct mars_info *info) { struct copy_input *input = output->brick->inputs[INPUT_B_IO]; return GENERIC_INPUT_CALL(input, mars_get_info, info); } static int copy_ref_get(struct copy_output *output, struct mref_object *mref) { struct copy_input *input; int index; int status; index = _determine_input(output->brick, mref); input = output->brick->inputs[index]; status = GENERIC_INPUT_CALL(input, mref_get, mref); if (status >= 0) { atomic_inc(&output->brick->io_flight); } return status; } static void copy_ref_put(struct copy_output *output, struct mref_object *mref) { struct copy_input *input; int index; index = _determine_input(output->brick, mref); input = output->brick->inputs[index]; GENERIC_INPUT_CALL(input, mref_put, mref); if (atomic_dec_and_test(&output->brick->io_flight)) { output->brick->trigger = true; wake_up_interruptible(&output->brick->event); } } static void copy_ref_io(struct copy_output *output, struct mref_object *mref) { struct copy_input *input; int index; index = _determine_input(output->brick, mref); input = output->brick->inputs[index]; GENERIC_INPUT_CALL(input, mref_io, mref); } static int copy_switch(struct copy_brick *brick) { static int version = 0; MARS_DBG("power.button = %d\n", brick->power.button); if (brick->power.button && !brick->terminated) { if (brick->power.led_on || brick->thread) goto done; mars_power_led_off((void*)brick, false); brick->is_aborting = false; if (!brick->thread) { brick->copy_last = brick->copy_start; brick->copy_dirty = 0; brick->terminated = false; mars_power_led_on((void*)brick, true); get_lamport(NULL, &brick->copy_last_stamp); brick->thread = brick_thread_create(_copy_thread, brick, "mars_copy%d", version++); if (brick->thread) { brick->trigger = true; } else { mars_power_led_on((void*)brick, false); mars_power_led_off((void*)brick, true); MARS_ERR("could not start copy thread\n"); } } } else { /* Tell thread to stop asynchronously */ mars_power_led_on((void*)brick, false); if (brick->thread) { /* Notice: this will be reported by the thread */ if (!brick->terminated) goto done; MARS_INF("stopping thread...\n"); brick_thread_stop(brick->thread); } /* for safety, and when the thread was not started */ mars_power_led_off((void*)brick, true); brick->terminated = false; } done: return 0; } //////////////// informational / statistics /////////////// static char *copy_statistics(struct copy_brick *brick, int verbose) { char *res = brick_string_alloc(1024); if (!res) return NULL; snprintf(res, 1024, "copy_start = %lld " "copy_last = %lld " "copy_dirty = %lld " "copy_end = %lld " "check_hint[0] = %lld " "check_hint[1] = %lld " "check_hint[2] = %lld " "check_hint[3] = %lld " "copy_error = %d " "copy_error_count = %d " "verify_ok_count = %d " "verify_error_count = %d " "low_dirty = %d " "is_aborting = %d " "clash = %lu | " "total clash_count = %d | " "io_flight = %d " "copy_read_flight = %d " "copy_write_flight = %d\n", brick->copy_start, brick->copy_last, brick->copy_dirty, brick->copy_end, brick->inputs[0]->check_hint, brick->inputs[1]->check_hint, brick->inputs[2]->check_hint, brick->inputs[3]->check_hint, brick->copy_error, brick->copy_error_count, brick->verify_ok_count, brick->verify_error_count, brick->low_dirty, brick->is_aborting, brick->clash, atomic_read(&brick->total_clash_count), atomic_read(&brick->io_flight), atomic_read(&brick->copy_read_flight), atomic_read(&brick->copy_write_flight)); return res; } static void copy_reset_statistics(struct copy_brick *brick) { atomic_set(&brick->total_clash_count, 0); } //////////////// object / aspect constructors / destructors /////////////// static int copy_mref_aspect_init_fn(struct generic_aspect *_ini) { struct copy_mref_aspect *ini = (void*)_ini; (void)ini; return 0; } static void copy_mref_aspect_exit_fn(struct generic_aspect *_ini) { struct copy_mref_aspect *ini = (void*)_ini; (void)ini; } MARS_MAKE_STATICS(copy); ////////////////////// brick constructors / destructors //////////////////// static void _free_pages(struct copy_brick *brick) { int i; for (i = 0; i < MAX_SUB_TABLES; i++) { struct copy_state *sub_table = brick->st[i]; if (!sub_table) { continue; } brick_block_free(sub_table, PAGE_SIZE); } brick_block_free(brick->st, PAGE_SIZE); } static int copy_brick_construct(struct copy_brick *brick) { int i; brick->st = brick_block_alloc(0, PAGE_SIZE); if (unlikely(!brick->st)) { MARS_ERR("cannot allocate state directory table.\n"); return -ENOMEM; } memset(brick->st, 0, PAGE_SIZE); for (i = 0; i < MAX_SUB_TABLES; i++) { struct copy_state *sub_table; // this should be usually optimized away as dead code if (unlikely(i >= MAX_SUB_TABLES)) { MARS_ERR("sorry, subtable index %d is too large.\n", i); _free_pages(brick); return -EINVAL; } sub_table = brick_block_alloc(0, PAGE_SIZE); brick->st[i] = sub_table; if (unlikely(!sub_table)) { MARS_ERR("cannot allocate state subtable %d.\n", i); _free_pages(brick); return -ENOMEM; } memset(sub_table, 0, PAGE_SIZE); } init_waitqueue_head(&brick->event); return 0; } static int copy_brick_destruct(struct copy_brick *brick) { _free_pages(brick); return 0; } static int copy_output_construct(struct copy_output *output) { return 0; } static int copy_output_destruct(struct copy_output *output) { return 0; } ///////////////////////// static structs //////////////////////// static struct copy_brick_ops copy_brick_ops = { .brick_switch = copy_switch, .brick_statistics = copy_statistics, .reset_statistics = copy_reset_statistics, }; static struct copy_output_ops copy_output_ops = { .mars_get_info = copy_get_info, .mref_get = copy_ref_get, .mref_put = copy_ref_put, .mref_io = copy_ref_io, }; const struct copy_input_type copy_input_type = { .type_name = "copy_input", .input_size = sizeof(struct copy_input), }; static const struct copy_input_type *copy_input_types[] = { ©_input_type, ©_input_type, ©_input_type, ©_input_type, }; const struct copy_output_type copy_output_type = { .type_name = "copy_output", .output_size = sizeof(struct copy_output), .master_ops = ©_output_ops, .output_construct = ©_output_construct, .output_destruct = ©_output_destruct, }; static const struct copy_output_type *copy_output_types[] = { ©_output_type, }; const struct copy_brick_type copy_brick_type = { .type_name = "copy_brick", .brick_size = sizeof(struct copy_brick), .max_inputs = 4, .max_outputs = 1, .master_ops = ©_brick_ops, .aspect_types = copy_aspect_types, .default_input_types = copy_input_types, .default_output_types = copy_output_types, .brick_construct = ©_brick_construct, .brick_destruct = ©_brick_destruct, }; EXPORT_SYMBOL_GPL(copy_brick_type); ////////////////// module init stuff ///////////////////////// int __init init_mars_copy(void) { MARS_INF("init_copy()\n"); return copy_register_brick_type(); } void exit_mars_copy(void) { MARS_INF("exit_copy()\n"); copy_unregister_brick_type(); }