[RFC 22/31] mars: add new module xio_trans_logger

From: Thomas Schoebel-Theuer
Date: Thu Dec 31 2015 - 06:40:32 EST


Signed-off-by: Thomas Schoebel-Theuer <tst@xxxxxxxxxxxxxxxxxx>
---
drivers/staging/mars/xio_bricks/xio_trans_logger.c | 3309 ++++++++++++++++++++
include/linux/xio/xio_trans_logger.h | 263 ++
2 files changed, 3572 insertions(+)
create mode 100644 drivers/staging/mars/xio_bricks/xio_trans_logger.c
create mode 100644 include/linux/xio/xio_trans_logger.h

diff --git a/drivers/staging/mars/xio_bricks/xio_trans_logger.c b/drivers/staging/mars/xio_bricks/xio_trans_logger.c
new file mode 100644
index 0000000..04d4c63
--- /dev/null
+++ b/drivers/staging/mars/xio_bricks/xio_trans_logger.c
@@ -0,0 +1,3309 @@
+/*
+ * MARS Long Distance Replication Software
+ *
+ * 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.
+ */
+
+/* Trans_Logger brick */
+
+#define XIO_DEBUGGING
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/bio.h>
+
+#include <linux/xio/xio.h>
+#include <linux/brick/lib_rank.h>
+#include <linux/brick/lib_limiter.h>
+
+#include <linux/xio/xio_trans_logger.h>
+
+/* variants */
+#define KEEP_UNIQUE
+#define DELAY_CALLERS /* this is _needed_ for production systems */
+/* When possible, queue 1 executes phase3_startio() directly without
+ * intermediate queueing into queue 3 = > may be irritating, but has better
+ * performance. NOTICE: when some day the IO scheduling should be
+ * different between queue 1 and 3, you MUST disable this in order
+ * to distinguish between them!
+ */
+#define SHORTCUT_1_to_3
+
+/* commenting this out is dangerous for data integrity! use only for testing! */
+#define USE_MEMCPY
+#define DO_WRITEBACK /* otherwise FAKE IO */
+#define REPLAY_DATA
+
+/* tuning */
+#ifdef BRICK_DEBUG_MEM
+#define CONF_TRANS_CHUNKSIZE (128 * 1024 - PAGE_SIZE * 2)
+#else
+#define CONF_TRANS_CHUNKSIZE (128 * 1024)
+#endif
+#define CONF_TRANS_MAX_AIO_SIZE PAGE_SIZE
+#define CONF_TRANS_ALIGN 0
+
+#define XIO_RPL(_args...) /*empty*/
+
+struct trans_logger_hash_anchor {
+ struct rw_semaphore hash_mutex;
+ struct list_head hash_anchor;
+};
+
+#define NR_HASH_PAGES 64
+
+#define MAX_HASH_PAGES (PAGE_SIZE / sizeof(struct trans_logger_hash_anchor *))
+#define HASH_PER_PAGE (PAGE_SIZE / sizeof(struct trans_logger_hash_anchor))
+#define HASH_TOTAL (NR_HASH_PAGES * HASH_PER_PAGE)
+
+/************************ global tuning ***********************/
+
+int trans_logger_completion_semantics = 1;
+
+int trans_logger_do_crc =
+#ifdef CONFIG_MARS_DEBUG
+ true;
+#else
+ false;
+#endif
+
+int trans_logger_mem_usage; /* in KB */
+
+int trans_logger_max_interleave = -1;
+
+int trans_logger_resume = 1;
+
+int trans_logger_replay_timeout = 1; /* in s */
+
+struct writeback_group global_writeback = {
+ .lock = __RW_LOCK_UNLOCKED(global_writeback.lock),
+ .group_anchor = LIST_HEAD_INIT(global_writeback.group_anchor),
+ .until_percent = 30,
+};
+
+static
+void add_to_group(struct writeback_group *gr, struct trans_logger_brick *brick)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&gr->lock, flags);
+ list_add_tail(&brick->group_head, &gr->group_anchor);
+ write_unlock_irqrestore(&gr->lock, flags);
+}
+
+static
+void remove_from_group(struct writeback_group *gr, struct trans_logger_brick *brick)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&gr->lock, flags);
+ list_del_init(&brick->group_head);
+ gr->leader = NULL;
+ write_unlock_irqrestore(&gr->lock, flags);
+}
+
+static
+struct trans_logger_brick *elect_leader(struct writeback_group *gr)
+{
+ struct trans_logger_brick *res = gr->leader;
+ struct list_head *tmp;
+ unsigned long flags;
+
+ if (res && gr->until_percent >= 0) {
+ loff_t used = atomic64_read(&res->shadow_mem_used);
+
+ if (used > gr->biggest * gr->until_percent / 100)
+ goto done;
+ }
+
+ read_lock_irqsave(&gr->lock, flags);
+ for (tmp = gr->group_anchor.next; tmp != &gr->group_anchor; tmp = tmp->next) {
+ struct trans_logger_brick *test = container_of(tmp, struct trans_logger_brick, group_head);
+ loff_t new_used = atomic64_read(&test->shadow_mem_used);
+
+ if (!res || new_used > atomic64_read(&res->shadow_mem_used)) {
+ res = test;
+ gr->biggest = new_used;
+ }
+ }
+ read_unlock_irqrestore(&gr->lock, flags);
+
+ gr->leader = res;
+
+done:
+ return res;
+}
+
+/************************ own type definitions ***********************/
+
+static inline
+int lh_cmp(loff_t *a, loff_t *b)
+{
+ if (*a < *b)
+ return -1;
+ if (*a > *b)
+ return 1;
+ return 0;
+}
+
+static inline
+int tr_cmp(struct pairing_heap_logger *_a, struct pairing_heap_logger *_b)
+{
+ struct logger_head *a = container_of(_a, struct logger_head, ph);
+ struct logger_head *b = container_of(_b, struct logger_head, ph);
+
+ return lh_cmp(a->lh_pos, b->lh_pos);
+}
+
+_PAIRING_HEAP_FUNCTIONS(static, logger, tr_cmp);
+
+static inline
+loff_t *lh_get(struct logger_head *th)
+{
+ return th->lh_pos;
+}
+
+QUEUE_FUNCTIONS(logger, struct logger_head, lh_head, lh_get, lh_cmp, logger);
+
+/************************* logger queue handling ***********************/
+
+static inline
+void qq_init(struct logger_queue *q, struct trans_logger_brick *brick)
+{
+ q_logger_init(q);
+ q->q_event = &brick->worker_event;
+ q->q_brick = brick;
+}
+
+static inline
+void qq_inc_flying(struct logger_queue *q)
+{
+ q_logger_inc_flying(q);
+}
+
+static inline
+void qq_dec_flying(struct logger_queue *q)
+{
+ q_logger_dec_flying(q);
+}
+
+static inline
+void qq_aio_insert(struct logger_queue *q, struct trans_logger_aio_aspect *aio_a)
+{
+ struct aio_object *aio = aio_a->object;
+
+ obj_get(aio); /* must be paired with __trans_logger_io_put() */
+ atomic_inc(&q->q_brick->inner_balance_count);
+
+ q_logger_insert(q, &aio_a->lh);
+}
+
+static inline
+void qq_wb_insert(struct logger_queue *q, struct writeback_info *wb)
+{
+ q_logger_insert(q, &wb->w_lh);
+}
+
+static inline
+void qq_aio_pushback(struct logger_queue *q, struct trans_logger_aio_aspect *aio_a)
+{
+ obj_check(aio_a->object);
+
+ q->pushback_count++;
+
+ q_logger_pushback(q, &aio_a->lh);
+}
+
+static inline
+void qq_wb_pushback(struct logger_queue *q, struct writeback_info *wb)
+{
+ q->pushback_count++;
+ q_logger_pushback(q, &wb->w_lh);
+}
+
+static inline
+struct trans_logger_aio_aspect *qq_aio_fetch(struct logger_queue *q)
+{
+ struct logger_head *test;
+ struct trans_logger_aio_aspect *aio_a = NULL;
+
+ test = q_logger_fetch(q);
+
+ if (test) {
+ aio_a = container_of(test, struct trans_logger_aio_aspect, lh);
+ obj_check(aio_a->object);
+ }
+ return aio_a;
+}
+
+static inline
+struct writeback_info *qq_wb_fetch(struct logger_queue *q)
+{
+ struct logger_head *test;
+ struct writeback_info *res = NULL;
+
+ test = q_logger_fetch(q);
+
+ if (test)
+ res = container_of(test, struct writeback_info, w_lh);
+ return res;
+}
+
+/************************ own helper functions ***********************/
+
+static inline
+int hash_fn(loff_t pos)
+{
+ /* simple and stupid */
+ long base_index = pos >> REGION_SIZE_BITS;
+
+ base_index += base_index / HASH_TOTAL / 7;
+ return base_index % HASH_TOTAL;
+}
+
+static inline
+struct trans_logger_aio_aspect *_hash_find(struct list_head *start,
+ loff_t pos,
+ int *max_len,
+ bool use_collect_head,
+ bool find_unstable)
+{
+ struct list_head *tmp;
+ struct trans_logger_aio_aspect *res = NULL;
+ int len = *max_len;
+
+ /* The lists are always sorted according to age (newest first).
+ * Caution: there may be duplicates in the list, some of them
+ * overlapping with the search area in many different ways.
+ */
+ for (tmp = start->next; tmp != start; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *test_a;
+ struct aio_object *test;
+ int diff;
+
+ if (use_collect_head)
+ test_a = container_of(tmp, struct trans_logger_aio_aspect, collect_head);
+ else
+ test_a = container_of(tmp, struct trans_logger_aio_aspect, hash_head);
+ test = test_a->object;
+
+ obj_check(test);
+
+ /* are the regions overlapping? */
+ if (pos >= test->io_pos + test->io_len || pos + len <= test->io_pos)
+ continue; /* not relevant */
+
+ /* searching for unstable elements (only in special cases) */
+ if (find_unstable && test_a->is_stable)
+ break;
+
+ diff = test->io_pos - pos;
+ if (diff <= 0) {
+ int restlen = test->io_len + diff;
+
+ res = test_a;
+ if (restlen < len)
+ len = restlen;
+ break;
+ }
+ if (diff < len)
+ len = diff;
+ }
+
+ *max_len = len;
+ return res;
+}
+
+static
+struct trans_logger_aio_aspect *hash_find(struct trans_logger_brick *brick,
+ loff_t pos,
+ int *max_len,
+ bool find_unstable)
+{
+
+ int hash = hash_fn(pos);
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[hash / HASH_PER_PAGE];
+ struct trans_logger_hash_anchor *start = &sub_table[hash % HASH_PER_PAGE];
+ struct trans_logger_aio_aspect *res;
+
+ atomic_inc(&brick->total_hash_find_count);
+
+ down_read(&start->hash_mutex);
+
+ res = _hash_find(&start->hash_anchor, pos, max_len, false, find_unstable);
+
+ /* Ensure the found aio can't go away...
+ */
+ if (res && res->object)
+ obj_get(res->object);
+
+ up_read(&start->hash_mutex);
+
+ return res;
+}
+
+static
+void hash_insert(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *elem_a)
+{
+ int hash = hash_fn(elem_a->object->io_pos);
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[hash / HASH_PER_PAGE];
+ struct trans_logger_hash_anchor *start = &sub_table[hash % HASH_PER_PAGE];
+
+ CHECK_HEAD_EMPTY(&elem_a->hash_head);
+ obj_check(elem_a->object);
+
+ /* only for statistics: */
+ atomic_inc(&brick->hash_count);
+ atomic_inc(&brick->total_hash_insert_count);
+
+ down_write(&start->hash_mutex);
+
+ list_add(&elem_a->hash_head, &start->hash_anchor);
+ elem_a->is_hashed = true;
+
+ up_write(&start->hash_mutex);
+}
+
+/* Find the transitive closure of overlapping requests
+ * and collect them into a list.
+ */
+static
+void hash_extend(struct trans_logger_brick *brick, loff_t *_pos, int *_len, struct list_head *collect_list)
+{
+ loff_t pos = *_pos;
+ int len = *_len;
+ int hash = hash_fn(pos);
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[hash / HASH_PER_PAGE];
+ struct trans_logger_hash_anchor *start = &sub_table[hash % HASH_PER_PAGE];
+ struct list_head *tmp;
+ bool extended;
+
+ if (collect_list)
+ CHECK_HEAD_EMPTY(collect_list);
+
+ atomic_inc(&brick->total_hash_extend_count);
+
+ down_read(&start->hash_mutex);
+
+ do {
+ extended = false;
+
+ for (tmp = start->hash_anchor.next; tmp != &start->hash_anchor; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *test_a;
+ struct aio_object *test;
+ loff_t diff;
+
+ test_a = container_of(tmp, struct trans_logger_aio_aspect, hash_head);
+ test = test_a->object;
+
+ obj_check(test);
+
+ /* are the regions overlapping? */
+ if (pos >= test->io_pos + test->io_len || pos + len <= test->io_pos)
+ continue; /* not relevant */
+
+ /* collision detection */
+ if (test_a->is_collected)
+ goto collision;
+
+ /* no writeback of non-persistent data */
+ if (!(test_a->is_persistent & test_a->is_completed))
+ goto collision;
+
+ /* extend the search region when necessary */
+ diff = pos - test->io_pos;
+ if (diff > 0) {
+ len += diff;
+ pos = test->io_pos;
+ extended = true;
+ }
+ diff = (test->io_pos + test->io_len) - (pos + len);
+ if (diff > 0) {
+ len += diff;
+ extended = true;
+ }
+ }
+ } while (extended); /* start over for transitive closure */
+
+ *_pos = pos;
+ *_len = len;
+
+ for (tmp = start->hash_anchor.next; tmp != &start->hash_anchor; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *test_a;
+ struct aio_object *test;
+
+ test_a = container_of(tmp, struct trans_logger_aio_aspect, hash_head);
+ test = test_a->object;
+
+ /* are the regions overlapping? */
+ if (pos >= test->io_pos + test->io_len || pos + len <= test->io_pos)
+ continue; /* not relevant */
+
+ /* collect */
+ CHECK_HEAD_EMPTY(&test_a->collect_head);
+ if (unlikely(test_a->is_collected))
+ XIO_ERR("collision detection did not work\n");
+ test_a->is_collected = true;
+ obj_check(test);
+ list_add_tail(&test_a->collect_head, collect_list);
+ }
+
+collision:
+ up_read(&start->hash_mutex);
+}
+
+/* Atomically put all elements from the list.
+ * All elements must reside in the same collision list.
+ */
+static inline
+void hash_put_all(struct trans_logger_brick *brick, struct list_head *list)
+{
+ struct list_head *tmp;
+ struct trans_logger_hash_anchor *start = NULL;
+ int first_hash = -1;
+
+ for (tmp = list->next; tmp != list; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *elem_a;
+ struct aio_object *elem;
+ int hash;
+
+ elem_a = container_of(tmp, struct trans_logger_aio_aspect, collect_head);
+ elem = elem_a->object;
+ CHECK_PTR(elem, err);
+ obj_check(elem);
+
+ hash = hash_fn(elem->io_pos);
+ if (!start) {
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[hash / HASH_PER_PAGE];
+
+ start = &sub_table[hash % HASH_PER_PAGE];
+ first_hash = hash;
+ down_write(&start->hash_mutex);
+ } else if (unlikely(hash != first_hash)) {
+ XIO_ERR("oops, different hashes: %d != %d\n", hash, first_hash);
+ }
+
+ if (!elem_a->is_hashed)
+ continue;
+
+ list_del_init(&elem_a->hash_head);
+ elem_a->is_hashed = false;
+ atomic_dec(&brick->hash_count);
+ }
+
+err:
+ if (start)
+ up_write(&start->hash_mutex);
+}
+
+static inline
+void hash_ensure_stableness(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *aio_a)
+{
+ if (!aio_a->is_stable) {
+ struct aio_object *aio = aio_a->object;
+ int hash = hash_fn(aio->io_pos);
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[hash / HASH_PER_PAGE];
+ struct trans_logger_hash_anchor *start = &sub_table[hash % HASH_PER_PAGE];
+
+ down_write(&start->hash_mutex);
+
+ aio_a->is_stable = true;
+
+ up_write(&start->hash_mutex);
+ }
+}
+
+static
+void _inf_callback(struct trans_logger_input *input, bool force)
+{
+ if (!force &&
+ input->inf_last_jiffies &&
+ input->inf_last_jiffies + 4 * HZ > (long long)jiffies)
+ goto out_return;
+ if (input->inf.inf_callback && input->is_operating) {
+ input->inf_last_jiffies = jiffies;
+
+ input->inf.inf_callback(&input->inf);
+
+ input->inf_last_jiffies = jiffies;
+ } else {
+ XIO_DBG("%p skipped callback, callback = %p is_operating = %d\n",
+ input,
+ input->inf.inf_callback,
+ input->is_operating);
+ }
+out_return:;
+}
+
+static inline
+int _congested(struct trans_logger_brick *brick)
+{
+ return atomic_read(&brick->q_phase[0].q_queued) ||
+ atomic_read(&brick->q_phase[0].q_flying) ||
+ atomic_read(&brick->q_phase[1].q_queued) ||
+ atomic_read(&brick->q_phase[1].q_flying) ||
+ atomic_read(&brick->q_phase[2].q_queued) ||
+ atomic_read(&brick->q_phase[2].q_flying) ||
+ atomic_read(&brick->q_phase[3].q_queued) ||
+ atomic_read(&brick->q_phase[3].q_flying);
+}
+
+/***************** own brick * input * output operations *****************/
+
+atomic_t global_mshadow_count = ATOMIC_INIT(0);
+
+atomic64_t global_mshadow_used = ATOMIC64_INIT(0);
+
+static
+int trans_logger_get_info(struct trans_logger_output *output, struct xio_info *info)
+{
+ struct trans_logger_input *input = output->brick->inputs[TL_INPUT_READ];
+
+ return GENERIC_INPUT_CALL(input, xio_get_info, info);
+}
+
+static
+int _make_sshadow(struct trans_logger_output *output,
+ struct trans_logger_aio_aspect *aio_a,
+ struct trans_logger_aio_aspect *mshadow_a)
+{
+ struct trans_logger_brick *brick = output->brick;
+ struct aio_object *aio = aio_a->object;
+ struct aio_object *mshadow;
+ int diff;
+
+ mshadow = mshadow_a->object;
+ if (unlikely(aio->io_len > mshadow->io_len)) {
+ XIO_ERR("oops %d -> %d\n", aio->io_len, mshadow->io_len);
+ aio->io_len = mshadow->io_len;
+ }
+ if (unlikely(mshadow_a == aio_a)) {
+ XIO_ERR("oops %p == %p\n", mshadow_a, aio_a);
+ return -EINVAL;
+ }
+
+ diff = aio->io_pos - mshadow->io_pos;
+ if (unlikely(diff < 0)) {
+ XIO_ERR("oops diff = %d\n", diff);
+ return -EINVAL;
+ }
+
+ /* Attach aio to the existing shadow ("slave shadow").
+ */
+ aio_a->shadow_data = mshadow_a->shadow_data + diff;
+ aio_a->do_dealloc = false;
+ if (!aio->io_data) { /* buffered IO */
+ aio->io_data = aio_a->shadow_data;
+ aio_a->do_buffered = true;
+ atomic_inc(&brick->total_sshadow_buffered_count);
+ }
+ aio->io_flags = mshadow->io_flags;
+ aio_a->shadow_aio = mshadow_a;
+ aio_a->my_brick = brick;
+
+ /* Get an ordinary internal reference
+ */
+ obj_get_first(aio); /* must be paired with __trans_logger_io_put() */
+ atomic_inc(&brick->inner_balance_count);
+
+ /* The internal reference from slave to master is already
+ * present due to hash_find(),
+ * such that the master cannot go away before the slave.
+ * It is compensated by master transition in __trans_logger_io_put()
+ */
+ atomic_inc(&brick->inner_balance_count);
+
+ atomic_inc(&brick->sshadow_count);
+ atomic_inc(&brick->total_sshadow_count);
+
+ if (unlikely(aio->io_len <= 0)) {
+ XIO_ERR("oops, len = %d\n", aio->io_len);
+ return -EINVAL;
+ }
+
+ return aio->io_len;
+}
+
+static
+int _read_io_get(struct trans_logger_output *output, struct trans_logger_aio_aspect *aio_a)
+{
+ struct trans_logger_brick *brick = output->brick;
+ struct aio_object *aio = aio_a->object;
+ struct trans_logger_input *input = brick->inputs[TL_INPUT_READ];
+ struct trans_logger_aio_aspect *mshadow_a;
+
+ /* Look if there is a newer version on the fly, shadowing
+ * the old one.
+ * When a shadow is found, use it as buffer for the aio.
+ */
+ mshadow_a = hash_find(brick, aio->io_pos, &aio->io_len, false);
+ if (!mshadow_a)
+ return GENERIC_INPUT_CALL(input, aio_get, aio);
+
+ return _make_sshadow(output, aio_a, mshadow_a);
+}
+
+static
+int _write_io_get(struct trans_logger_output *output, struct trans_logger_aio_aspect *aio_a)
+{
+ struct trans_logger_brick *brick = output->brick;
+ struct aio_object *aio = aio_a->object;
+ void *data;
+
+#ifdef KEEP_UNIQUE
+ struct trans_logger_aio_aspect *mshadow_a;
+
+#endif
+
+#ifdef CONFIG_MARS_DEBUG
+ if (unlikely(aio->io_len <= 0)) {
+ XIO_ERR("oops, io_len = %d\n", aio->io_len);
+ return -EINVAL;
+ }
+#endif
+
+#ifdef KEEP_UNIQUE
+ mshadow_a = hash_find(brick, aio->io_pos, &aio->io_len, true);
+ if (mshadow_a)
+ return _make_sshadow(output, aio_a, mshadow_a);
+#endif
+
+#ifdef DELAY_CALLERS
+ /* delay in case of too many master shadows / memory shortage */
+ wait_event_interruptible_timeout(brick->caller_event,
+ !brick->delay_callers &&
+ (brick_global_memlimit < 1024 ||
+ atomic64_read(&global_mshadow_used) / 1024 < brick_global_memlimit),
+ HZ / 2);
+#endif
+
+ /* create a new master shadow */
+ data = brick_block_alloc(aio->io_pos, (aio_a->alloc_len = aio->io_len));
+ atomic64_add(aio->io_len, &brick->shadow_mem_used);
+#ifdef CONFIG_MARS_DEBUG
+ memset(data, 0x11, aio->io_len);
+#endif
+ aio_a->shadow_data = data;
+ aio_a->do_dealloc = true;
+ if (!aio->io_data) { /* buffered IO */
+ aio->io_data = data;
+ aio_a->do_buffered = true;
+ atomic_inc(&brick->total_mshadow_buffered_count);
+ }
+ aio_a->my_brick = brick;
+ aio->io_flags = 0;
+ aio_a->shadow_aio = aio_a; /* cyclic self-reference = > indicates master shadow */
+
+ atomic_inc(&brick->mshadow_count);
+ atomic_inc(&brick->total_mshadow_count);
+ atomic_inc(&global_mshadow_count);
+ atomic64_add(aio->io_len, &global_mshadow_used);
+
+ atomic_inc(&brick->inner_balance_count);
+ obj_get_first(aio); /* must be paired with __trans_logger_io_put() */
+
+ return aio->io_len;
+}
+
+static
+int trans_logger_io_get(struct trans_logger_output *output, struct aio_object *aio)
+{
+ struct trans_logger_brick *brick;
+ struct trans_logger_aio_aspect *aio_a;
+ loff_t base_offset;
+
+ CHECK_PTR(output, err);
+ brick = output->brick;
+ CHECK_PTR(brick, err);
+ CHECK_PTR(aio, err);
+
+ aio_a = trans_logger_aio_get_aspect(brick, aio);
+ CHECK_PTR(aio_a, err);
+ CHECK_ASPECT(aio_a, aio, err);
+
+ atomic_inc(&brick->outer_balance_count);
+
+ if (aio->obj_initialized) { /* setup already performed */
+ obj_check(aio);
+ obj_get(aio); /* must be paired with __trans_logger_io_put() */
+ return aio->io_len;
+ }
+
+ get_lamport(&aio_a->stamp);
+
+ if (aio->io_len > CONF_TRANS_MAX_AIO_SIZE && CONF_TRANS_MAX_AIO_SIZE > 0)
+ aio->io_len = CONF_TRANS_MAX_AIO_SIZE;
+
+ /* ensure that REGION_SIZE boundaries are obeyed by hashing */
+ base_offset = aio->io_pos & (loff_t)(REGION_SIZE - 1);
+ if (aio->io_len > REGION_SIZE - base_offset)
+ aio->io_len = REGION_SIZE - base_offset;
+
+ if (aio->io_may_write == READ)
+ return _read_io_get(output, aio_a);
+
+ if (unlikely(brick->stopped_logging)) { /* only in EMERGENCY mode */
+ aio_a->is_emergency = true;
+ /* Wait until writeback has finished.
+ * We have to this because writeback is out-of-order.
+ * Otherwise consistency could be violated for some time.
+ */
+ while (_congested(brick)) {
+ /* in case of emergency, busy-wait should be acceptable */
+ brick_msleep(HZ / 10);
+ }
+ return _read_io_get(output, aio_a);
+ }
+
+ /* FIXME: THIS IS PROVISIONARY (use event instead)
+ */
+ while (unlikely(!brick->power.on_led))
+ brick_msleep(HZ / 10);
+
+ return _write_io_get(output, aio_a);
+
+err:
+ return -EINVAL;
+}
+
+static void pos_complete(struct trans_logger_aio_aspect *orig_aio_a);
+
+static
+void __trans_logger_io_put(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *aio_a)
+{
+ struct aio_object *aio;
+ struct trans_logger_aio_aspect *shadow_a;
+ struct trans_logger_input *input;
+
+restart:
+ CHECK_PTR(aio_a, err);
+ aio = aio_a->object;
+ CHECK_PTR(aio, err);
+
+ obj_check(aio);
+
+ /* are we a shadow (whether master or slave)? */
+ shadow_a = aio_a->shadow_aio;
+ if (shadow_a) {
+ bool finished;
+
+ CHECK_PTR(shadow_a, err);
+ CHECK_PTR(shadow_a->object, err);
+ obj_check(shadow_a->object);
+
+ finished = obj_put(aio);
+ atomic_dec(&brick->inner_balance_count);
+ if (unlikely(finished && aio_a->is_hashed)) {
+ XIO_ERR("trying to put a hashed aio, pos = %lld len = %d\n", aio->io_pos, aio->io_len);
+ finished = false; /* leaves a memleak */
+ }
+
+ if (!finished)
+ goto out_return;
+
+ CHECK_HEAD_EMPTY(&aio_a->lh.lh_head);
+ CHECK_HEAD_EMPTY(&aio_a->hash_head);
+ CHECK_HEAD_EMPTY(&aio_a->replay_head);
+ CHECK_HEAD_EMPTY(&aio_a->collect_head);
+ CHECK_HEAD_EMPTY(&aio_a->sub_list);
+ CHECK_HEAD_EMPTY(&aio_a->sub_head);
+
+ if (aio_a->is_collected && likely(aio_a->wb_error >= 0))
+ pos_complete(aio_a);
+
+ CHECK_HEAD_EMPTY(&aio_a->pos_head);
+
+ if (shadow_a != aio_a) { /* we are a slave shadow */
+ /* XIO_DBG("slave\n"); */
+ atomic_dec(&brick->sshadow_count);
+ CHECK_HEAD_EMPTY(&aio_a->hash_head);
+ obj_free(aio);
+ /* now put the master shadow */
+ aio_a = shadow_a;
+ goto restart;
+ }
+ /* we are a master shadow */
+ CHECK_PTR(aio_a->shadow_data, err);
+ if (aio_a->do_dealloc) {
+ brick_block_free(aio_a->shadow_data, aio_a->alloc_len);
+ atomic64_sub(aio->io_len, &brick->shadow_mem_used);
+ aio_a->shadow_data = NULL;
+ aio_a->do_dealloc = false;
+ }
+ if (aio_a->do_buffered)
+ aio->io_data = NULL;
+ atomic_dec(&brick->mshadow_count);
+ atomic_dec(&global_mshadow_count);
+ atomic64_sub(aio->io_len, &global_mshadow_used);
+ obj_free(aio);
+ goto out_return;
+ }
+
+ /* only READ is allowed on non-shadow buffers */
+ if (unlikely(aio->io_rw != READ && !aio_a->is_emergency))
+ XIO_FAT("bad operation %d on non-shadow\n", aio->io_rw);
+
+ /* no shadow = > call through */
+ input = brick->inputs[TL_INPUT_READ];
+ CHECK_PTR(input, err);
+
+ GENERIC_INPUT_CALL(input, aio_put, aio);
+
+err:;
+out_return:;
+}
+
+static
+void _trans_logger_io_put(struct trans_logger_output *output, struct aio_object *aio)
+{
+ struct trans_logger_aio_aspect *aio_a;
+
+ aio_a = trans_logger_aio_get_aspect(output->brick, aio);
+ CHECK_PTR(aio_a, err);
+ CHECK_ASPECT(aio_a, aio, err);
+
+ __trans_logger_io_put(output->brick, aio_a);
+ goto out_return;
+err:
+ XIO_FAT("giving up...\n");
+out_return:;
+}
+
+static
+void trans_logger_io_put(struct trans_logger_output *output, struct aio_object *aio)
+{
+ struct trans_logger_brick *brick = output->brick;
+
+ atomic_dec(&brick->outer_balance_count);
+ _trans_logger_io_put(output, aio);
+}
+
+static
+void _trans_logger_endio(struct generic_callback *cb)
+{
+ struct trans_logger_aio_aspect *aio_a;
+ struct trans_logger_brick *brick;
+
+ aio_a = cb->cb_private;
+ CHECK_PTR(aio_a, err);
+ if (unlikely(&aio_a->cb != cb)) {
+ XIO_FAT("bad callback -- hanging up\n");
+ goto err;
+ }
+ brick = aio_a->my_brick;
+ CHECK_PTR(brick, err);
+
+ NEXT_CHECKED_CALLBACK(cb, err);
+
+ atomic_dec(&brick->any_fly_count);
+ atomic_inc(&brick->total_cb_count);
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+err:
+ XIO_FAT("cannot handle callback\n");
+out_return:;
+}
+
+static
+void trans_logger_io_io(struct trans_logger_output *output, struct aio_object *aio)
+{
+ struct trans_logger_brick *brick = output->brick;
+ struct trans_logger_aio_aspect *aio_a;
+ struct trans_logger_aio_aspect *shadow_a;
+ struct trans_logger_input *input;
+
+ obj_check(aio);
+
+ aio_a = trans_logger_aio_get_aspect(brick, aio);
+ CHECK_PTR(aio_a, err);
+ CHECK_ASPECT(aio_a, aio, err);
+
+ /* statistics */
+ if (aio->io_rw)
+ atomic_inc(&brick->total_write_count);
+ else
+ atomic_inc(&brick->total_read_count);
+ /* is this a shadow buffer? */
+ shadow_a = aio_a->shadow_aio;
+ if (shadow_a) {
+ CHECK_HEAD_EMPTY(&aio_a->lh.lh_head);
+ CHECK_HEAD_EMPTY(&aio_a->hash_head);
+ CHECK_HEAD_EMPTY(&aio_a->pos_head);
+
+ obj_get(aio); /* must be paired with __trans_logger_io_put() */
+ atomic_inc(&brick->inner_balance_count);
+
+ qq_aio_insert(&brick->q_phase[0], aio_a);
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+ }
+
+ /* only READ is allowed on non-shadow buffers */
+ if (unlikely(aio->io_rw != READ && !aio_a->is_emergency))
+ XIO_FAT("bad operation %d on non-shadow\n", aio->io_rw);
+
+ atomic_inc(&brick->any_fly_count);
+
+ aio_a->my_brick = brick;
+
+ INSERT_CALLBACK(aio, &aio_a->cb, _trans_logger_endio, aio_a);
+
+ input = output->brick->inputs[TL_INPUT_READ];
+
+ GENERIC_INPUT_CALL(input, aio_io, aio);
+ goto out_return;
+err:
+ XIO_FAT("cannot handle IO\n");
+out_return:;
+}
+
+/***************************** writeback info *****************************/
+
+/* save final completion status when necessary
+ */
+static
+void pos_complete(struct trans_logger_aio_aspect *orig_aio_a)
+{
+ struct trans_logger_brick *brick = orig_aio_a->my_brick;
+ struct trans_logger_input *log_input = orig_aio_a->log_input;
+ loff_t finished;
+ struct list_head *tmp;
+
+ CHECK_PTR(brick, err);
+ CHECK_PTR(log_input, err);
+
+ atomic_inc(&brick->total_writeback_count);
+
+ tmp = &orig_aio_a->pos_head;
+
+ down(&log_input->inf_mutex);
+
+ finished = orig_aio_a->log_pos;
+ /* am I the first member? (means "youngest" list entry) */
+ if (tmp == log_input->pos_list.next) {
+ if (unlikely(finished <= log_input->inf.inf_min_pos))
+ XIO_ERR("backskip in log writeback: %lld -> %lld\n", log_input->inf.inf_min_pos, finished);
+ if (unlikely(finished > log_input->inf.inf_max_pos))
+ XIO_ERR("min_pos > max_pos: %lld > %lld\n", finished, log_input->inf.inf_max_pos);
+ log_input->inf.inf_min_pos = finished;
+ get_lamport(&log_input->inf.inf_min_pos_stamp);
+ _inf_callback(log_input, false);
+ } else {
+ struct trans_logger_aio_aspect *prev_aio_a;
+
+ prev_aio_a = container_of(tmp->prev, struct trans_logger_aio_aspect, pos_head);
+ if (unlikely(finished <= prev_aio_a->log_pos)) {
+ XIO_ERR("backskip: %lld -> %lld\n", finished, prev_aio_a->log_pos);
+ } else {
+ /* Transitively transfer log_pos to the predecessor
+ * to correctly reflect the committed region.
+ */
+ prev_aio_a->log_pos = finished;
+ }
+ }
+
+ list_del_init(tmp);
+ atomic_dec(&log_input->pos_count);
+
+ up(&log_input->inf_mutex);
+err:;
+}
+
+static
+void free_writeback(struct writeback_info *wb)
+{
+ struct list_head *tmp;
+
+ if (unlikely(wb->w_error < 0)) {
+ XIO_ERR("writeback error = %d at pos = %lld len = %d, writeback is incomplete\n",
+ wb->w_error,
+ wb->w_pos,
+ wb->w_len);
+ }
+
+ /* Now complete the original requests.
+ */
+ while ((tmp = wb->w_collect_list.next) != &wb->w_collect_list) {
+ struct trans_logger_aio_aspect *orig_aio_a;
+ struct aio_object *orig_aio;
+
+ list_del_init(tmp);
+
+ orig_aio_a = container_of(tmp, struct trans_logger_aio_aspect, collect_head);
+ orig_aio = orig_aio_a->object;
+
+ obj_check(orig_aio);
+ if (unlikely(!orig_aio_a->is_collected)) {
+ XIO_ERR("request %lld (len = %d) was not collected\n",
+ orig_aio->io_pos,
+ orig_aio->io_len);
+ }
+ if (unlikely(wb->w_error < 0))
+ orig_aio_a->wb_error = wb->w_error;
+
+ __trans_logger_io_put(orig_aio_a->my_brick, orig_aio_a);
+ }
+
+ brick_mem_free(wb);
+}
+
+/* Generic endio() for writeback_info
+ */
+static
+void wb_endio(struct generic_callback *cb)
+{
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+ struct trans_logger_brick *brick;
+ struct writeback_info *wb;
+ atomic_t *dec;
+ int rw;
+ void (**_endio)(struct generic_callback *cb);
+ void (*endio)(struct generic_callback *cb);
+
+ LAST_CALLBACK(cb);
+ sub_aio_a = cb->cb_private;
+ CHECK_PTR(sub_aio_a, err);
+ sub_aio = sub_aio_a->object;
+ CHECK_PTR(sub_aio, err);
+ wb = sub_aio_a->wb;
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+
+ if (cb->cb_error < 0)
+ wb->w_error = cb->cb_error;
+
+ atomic_dec(&brick->wb_balance_count);
+
+ rw = sub_aio_a->orig_rw;
+ dec = rw ? &wb->w_sub_write_count : &wb->w_sub_read_count;
+ CHECK_ATOMIC(dec, 1);
+ if (!atomic_dec_and_test(dec))
+ goto done;
+
+ _endio = rw ? &wb->write_endio : &wb->read_endio;
+ endio = *_endio;
+ *_endio = NULL;
+ if (likely(endio))
+ endio(cb);
+ else
+ XIO_ERR("internal: no endio defined\n");
+done:
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+err:
+ XIO_FAT("hanging up....\n");
+out_return:;
+}
+
+/* Atomically create writeback info, based on "snapshot" of current hash
+ * state.
+ * Notice that the hash can change during writeback IO, thus we need
+ * struct writeback_info to precisely catch that information at a single
+ * point in time.
+ */
+static
+struct writeback_info *make_writeback(struct trans_logger_brick *brick, loff_t pos, int len)
+{
+ struct writeback_info *wb;
+ struct trans_logger_input *read_input;
+ struct trans_logger_input *write_input;
+ int write_input_nr;
+
+ /* Allocate structure representing a bunch of adjacent writebacks
+ */
+ wb = brick_zmem_alloc(sizeof(struct writeback_info));
+ if (unlikely(len < 0))
+ XIO_ERR("len = %d\n", len);
+
+ wb->w_brick = brick;
+ wb->w_pos = pos;
+ wb->w_len = len;
+ wb->w_lh.lh_pos = &wb->w_pos;
+ INIT_LIST_HEAD(&wb->w_lh.lh_head);
+ INIT_LIST_HEAD(&wb->w_collect_list);
+ INIT_LIST_HEAD(&wb->w_sub_read_list);
+ INIT_LIST_HEAD(&wb->w_sub_write_list);
+
+ /* Atomically fetch transitive closure on all requests
+ * overlapping with the current search region.
+ */
+ hash_extend(brick, &wb->w_pos, &wb->w_len, &wb->w_collect_list);
+
+ if (list_empty(&wb->w_collect_list))
+ goto collision;
+
+ pos = wb->w_pos;
+ len = wb->w_len;
+
+ if (unlikely(len < 0))
+ XIO_ERR("len = %d\n", len);
+
+ /* Determine the "channels" we want to operate on
+ */
+ read_input = brick->inputs[TL_INPUT_READ];
+ write_input_nr = TL_INPUT_WRITEBACK;
+ write_input = brick->inputs[write_input_nr];
+ if (!write_input->connect) {
+ write_input_nr = TL_INPUT_READ;
+ write_input = read_input;
+ }
+
+ /* Create sub_aios for read of old disk version (phase1)
+ */
+ if (brick->log_reads) {
+ while (len > 0) {
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+ struct trans_logger_input *log_input;
+ int this_len;
+ int status;
+
+ sub_aio = trans_logger_alloc_aio(brick);
+
+ sub_aio->io_pos = pos;
+ sub_aio->io_len = len;
+ sub_aio->io_may_write = READ;
+ sub_aio->io_rw = READ;
+ sub_aio->io_data = NULL;
+
+ sub_aio_a = trans_logger_aio_get_aspect(brick, sub_aio);
+ CHECK_PTR(sub_aio_a, err);
+ CHECK_ASPECT(sub_aio_a, sub_aio, err);
+
+ sub_aio_a->my_input = read_input;
+ log_input = brick->inputs[brick->log_input_nr];
+ sub_aio_a->log_input = log_input;
+ atomic_inc(&log_input->log_obj_count);
+ sub_aio_a->my_brick = brick;
+ sub_aio_a->orig_rw = READ;
+ sub_aio_a->wb = wb;
+
+ status = GENERIC_INPUT_CALL(read_input, aio_get, sub_aio);
+ if (unlikely(status < 0)) {
+ XIO_FAT("cannot get sub_aio, status = %d\n", status);
+ goto err;
+ }
+
+ list_add_tail(&sub_aio_a->sub_head, &wb->w_sub_read_list);
+ atomic_inc(&wb->w_sub_read_count);
+ atomic_inc(&brick->wb_balance_count);
+
+ this_len = sub_aio->io_len;
+ pos += this_len;
+ len -= this_len;
+ }
+ /* Re-init for startover
+ */
+ pos = wb->w_pos;
+ len = wb->w_len;
+ }
+
+ /* Always create sub_aios for writeback (phase3)
+ */
+ while (len > 0) {
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+ struct trans_logger_aio_aspect *orig_aio_a;
+ struct aio_object *orig_aio;
+ struct trans_logger_input *log_input;
+ void *data;
+ int this_len = len;
+ int diff;
+ int status;
+
+ atomic_inc(&brick->total_hash_find_count);
+
+ orig_aio_a = _hash_find(&wb->w_collect_list, pos, &this_len, true, false);
+ if (unlikely(!orig_aio_a)) {
+ XIO_FAT("could not find data\n");
+ goto err;
+ }
+
+ orig_aio = orig_aio_a->object;
+ diff = pos - orig_aio->io_pos;
+ if (unlikely(diff < 0)) {
+ XIO_FAT("bad diff %d\n", diff);
+ goto err;
+ }
+ data = orig_aio_a->shadow_data + diff;
+
+ sub_aio = trans_logger_alloc_aio(brick);
+
+ sub_aio->io_pos = pos;
+ sub_aio->io_len = this_len;
+ sub_aio->io_may_write = WRITE;
+ sub_aio->io_rw = WRITE;
+ sub_aio->io_data = data;
+
+ sub_aio_a = trans_logger_aio_get_aspect(brick, sub_aio);
+ CHECK_PTR(sub_aio_a, err);
+ CHECK_ASPECT(sub_aio_a, sub_aio, err);
+
+ sub_aio_a->orig_aio_a = orig_aio_a;
+ sub_aio_a->my_input = write_input;
+ log_input = orig_aio_a->log_input;
+ sub_aio_a->log_input = log_input;
+ atomic_inc(&log_input->log_obj_count);
+ sub_aio_a->my_brick = brick;
+ sub_aio_a->orig_rw = WRITE;
+ sub_aio_a->wb = wb;
+
+ status = GENERIC_INPUT_CALL(write_input, aio_get, sub_aio);
+ if (unlikely(status < 0)) {
+ XIO_FAT("cannot get sub_aio, status = %d\n", status);
+ wb->w_error = status;
+ goto err;
+ }
+
+ list_add_tail(&sub_aio_a->sub_head, &wb->w_sub_write_list);
+ atomic_inc(&wb->w_sub_write_count);
+ atomic_inc(&brick->wb_balance_count);
+
+ this_len = sub_aio->io_len;
+ pos += this_len;
+ len -= this_len;
+ }
+
+ return wb;
+
+err:
+ XIO_ERR("cleaning up...\n");
+collision:
+ if (wb)
+ free_writeback(wb);
+ return NULL;
+}
+
+static inline
+void _fire_one(struct list_head *tmp, bool do_update)
+{
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+ struct trans_logger_input *sub_input;
+
+ sub_aio_a = container_of(tmp, struct trans_logger_aio_aspect, sub_head);
+ sub_aio = sub_aio_a->object;
+
+ if (unlikely(sub_aio_a->is_fired)) {
+ XIO_ERR("trying to fire twice\n");
+ goto out_return;
+ }
+ sub_aio_a->is_fired = true;
+
+ SETUP_CALLBACK(sub_aio, wb_endio, sub_aio_a);
+
+ sub_input = sub_aio_a->my_input;
+
+#ifdef DO_WRITEBACK
+ GENERIC_INPUT_CALL(sub_input, aio_io, sub_aio);
+#else
+ SIMPLE_CALLBACK(sub_aio, 0);
+#endif
+ if (do_update) { /* CHECK: shouldn't we do this always? */
+ GENERIC_INPUT_CALL(sub_input, aio_put, sub_aio);
+ }
+out_return:;
+}
+
+static inline
+void fire_writeback(struct list_head *start, bool do_update)
+{
+ struct list_head *tmp;
+
+ /* Caution! The wb structure may get deallocated
+ * during _fire_one() in some cases (e.g. when the
+ * callback is directly called by the aio_io operation).
+ * Ensure that no ptr dereferencing can take
+ * place after working on the last list member.
+ */
+ tmp = start->next;
+ while (tmp != start) {
+ struct list_head *next = tmp->next;
+
+ list_del_init(tmp);
+ _fire_one(tmp, do_update);
+ tmp = next;
+ }
+}
+
+static inline
+void update_max_pos(struct trans_logger_aio_aspect *orig_aio_a)
+{
+ loff_t max_pos = orig_aio_a->log_pos;
+ struct trans_logger_input *log_input = orig_aio_a->log_input;
+
+ CHECK_PTR(log_input, done);
+
+ down(&log_input->inf_mutex);
+
+ if (unlikely(max_pos < log_input->inf.inf_min_pos))
+ XIO_ERR("new max_pos < min_pos: %lld < %lld\n", max_pos, log_input->inf.inf_min_pos);
+ if (log_input->inf.inf_max_pos < max_pos) {
+ log_input->inf.inf_max_pos = max_pos;
+ get_lamport(&log_input->inf.inf_max_pos_stamp);
+ _inf_callback(log_input, false);
+ }
+
+ up(&log_input->inf_mutex);
+done:;
+}
+
+static inline
+void update_writeback_info(struct writeback_info *wb)
+{
+ struct list_head *start = &wb->w_collect_list;
+ struct list_head *tmp;
+
+ /* Notice: in case of log rotation, each list member
+ * may belong to a different log_input.
+ */
+ for (tmp = start->next; tmp != start; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *orig_aio_a;
+
+ orig_aio_a = container_of(tmp, struct trans_logger_aio_aspect, collect_head);
+ update_max_pos(orig_aio_a);
+ }
+}
+
+/***************************** worker thread *****************************/
+
+/*********************************************************************
+ * Phase 0: write transaction log entry for the original write request.
+ */
+
+static
+void _complete(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *orig_aio_a, int error, bool pre_io)
+{
+ struct aio_object *orig_aio;
+
+ orig_aio = orig_aio_a->object;
+ CHECK_PTR(orig_aio, err);
+
+ if (orig_aio_a->is_completed ||
+ (pre_io &&
+ (trans_logger_completion_semantics >= 2 ||
+ (trans_logger_completion_semantics >= 1 && !orig_aio->io_skip_sync)))) {
+ goto done;
+ }
+
+ if (cmpxchg(&orig_aio_a->is_completed, false, true))
+ goto done;
+
+ atomic_dec(&brick->log_fly_count);
+
+ if (likely(error >= 0)) {
+ aio_checksum(orig_aio);
+ orig_aio->io_flags &= ~AIO_WRITING;
+ orig_aio->io_flags |= AIO_UPTODATE;
+ }
+ CHECKED_CALLBACK(orig_aio, error, err);
+
+done:
+ goto out_return;
+err:
+ XIO_ERR("giving up...\n");
+out_return:;
+}
+
+static
+void phase0_preio(void *private)
+{
+ struct trans_logger_aio_aspect *orig_aio_a;
+ struct trans_logger_brick *brick;
+
+ orig_aio_a = private;
+ CHECK_PTR(orig_aio_a, err);
+ CHECK_PTR(orig_aio_a->object, err);
+ brick = orig_aio_a->my_brick;
+ CHECK_PTR(brick, err);
+
+ /* signal completion to the upper layer */
+/**/
+
+ obj_check(orig_aio_a->object);
+ _complete(brick, orig_aio_a, 0, true);
+ obj_check(orig_aio_a->object);
+ goto out_return;
+err:
+ XIO_ERR("giving up...\n");
+out_return:;
+}
+
+static
+void phase0_endio(void *private, int error)
+{
+ struct aio_object *orig_aio;
+ struct trans_logger_aio_aspect *orig_aio_a;
+ struct trans_logger_brick *brick;
+
+ orig_aio_a = private;
+ CHECK_PTR(orig_aio_a, err);
+
+ brick = orig_aio_a->my_brick;
+ CHECK_PTR(brick, err);
+ orig_aio = orig_aio_a->object;
+ CHECK_PTR(orig_aio, err);
+
+ orig_aio_a->is_persistent = true;
+ qq_dec_flying(&brick->q_phase[0]);
+
+ _CHECK(orig_aio_a->shadow_aio, err);
+
+ /* signal completion to the upper layer */
+ _complete(brick, orig_aio_a, error, false);
+
+ /* Queue up for the next phase.
+ */
+ qq_aio_insert(&brick->q_phase[1], orig_aio_a);
+
+ /* Undo the above pinning
+ */
+ __trans_logger_io_put(brick, orig_aio_a);
+
+ banning_reset(&brick->q_phase[0].q_banning);
+
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+err:
+ XIO_ERR("giving up...\n");
+out_return:;
+}
+
+static
+bool phase0_startio(struct trans_logger_aio_aspect *orig_aio_a)
+{
+ struct aio_object *orig_aio;
+ struct trans_logger_brick *brick;
+ struct trans_logger_input *input;
+ struct log_status *logst;
+ loff_t log_pos;
+ void *data;
+ bool ok;
+
+ CHECK_PTR(orig_aio_a, err);
+ orig_aio = orig_aio_a->object;
+ CHECK_PTR(orig_aio, err);
+ brick = orig_aio_a->my_brick;
+ CHECK_PTR(brick, err);
+ input = orig_aio_a->log_input;
+ CHECK_PTR(input, err);
+ logst = &input->logst;
+ logst->do_crc = trans_logger_do_crc;
+
+ {
+ struct log_header l = {
+ .l_stamp = orig_aio_a->stamp,
+ .l_pos = orig_aio->io_pos,
+ .l_len = orig_aio->io_len,
+ .l_code = CODE_WRITE_NEW,
+ };
+ data = log_reserve(logst, &l);
+ }
+ if (unlikely(!data))
+ goto err;
+
+ hash_ensure_stableness(brick, orig_aio_a);
+
+ memcpy(data, orig_aio_a->shadow_data, orig_aio->io_len);
+
+ /* Pin aio->obj_count so it can't go away
+ * after _complete().
+ * This may happen rather early in phase0_preio().
+ */
+ obj_get(orig_aio); /* must be paired with __trans_logger_io_put() */
+ atomic_inc(&brick->inner_balance_count);
+ atomic_inc(&brick->log_fly_count);
+
+ ok = log_finalize(logst, orig_aio->io_len, phase0_endio, orig_aio_a);
+ if (unlikely(!ok)) {
+ atomic_dec(&brick->log_fly_count);
+ goto err;
+ }
+ log_pos = logst->log_pos + logst->offset;
+ orig_aio_a->log_pos = log_pos;
+
+ /* update new log_pos in the symlinks */
+ down(&input->inf_mutex);
+ input->inf.inf_log_pos = log_pos;
+ memcpy(&input->inf.inf_log_pos_stamp, &logst->log_pos_stamp, sizeof(input->inf.inf_log_pos_stamp));
+ _inf_callback(input, false);
+
+#ifdef CONFIG_MARS_DEBUG
+ if (!list_empty(&input->pos_list)) {
+ struct trans_logger_aio_aspect *last_aio_a;
+
+ last_aio_a = container_of(input->pos_list.prev, struct trans_logger_aio_aspect, pos_head);
+ if (last_aio_a->log_pos >= orig_aio_a->log_pos)
+ XIO_ERR("backskip in pos_list, %lld >= %lld\n", last_aio_a->log_pos, orig_aio_a->log_pos);
+ }
+#endif
+ list_add_tail(&orig_aio_a->pos_head, &input->pos_list);
+ atomic_inc(&input->pos_count);
+ up(&input->inf_mutex);
+
+ qq_inc_flying(&brick->q_phase[0]);
+
+ phase0_preio(orig_aio_a);
+
+ return true;
+
+err:
+ return false;
+}
+
+static
+bool prep_phase_startio(struct trans_logger_aio_aspect *aio_a)
+{
+ struct aio_object *aio = aio_a->object;
+ struct trans_logger_aio_aspect *shadow_a;
+ struct trans_logger_brick *brick;
+
+ CHECK_PTR(aio, err);
+ shadow_a = aio_a->shadow_aio;
+ CHECK_PTR(shadow_a, err);
+ brick = aio_a->my_brick;
+ CHECK_PTR(brick, err);
+
+ if (aio->io_rw == READ) {
+ /* nothing to do: directly signal success. */
+ struct aio_object *shadow = shadow_a->object;
+
+ if (unlikely(shadow == aio))
+ XIO_ERR("oops, we should be a slave shadow, but are a master one\n");
+#ifdef USE_MEMCPY
+ if (aio_a->shadow_data != aio->io_data) {
+ if (unlikely(aio->io_len <= 0 || aio->io_len > PAGE_SIZE))
+ XIO_ERR("implausible io_len = %d\n", aio->io_len);
+ memcpy(aio->io_data, aio_a->shadow_data, aio->io_len);
+ }
+#endif
+ aio->io_flags |= AIO_UPTODATE;
+
+ CHECKED_CALLBACK(aio, 0, err);
+
+ __trans_logger_io_put(brick, aio_a);
+
+ return true;
+ }
+ /* else WRITE */
+ CHECK_HEAD_EMPTY(&aio_a->lh.lh_head);
+ CHECK_HEAD_EMPTY(&aio_a->hash_head);
+ if (unlikely(aio->io_flags & (AIO_READING | AIO_WRITING)))
+ XIO_ERR("bad flags %d\n", aio->io_flags);
+ /* In case of non-buffered IO, the buffer is
+ * under control of the user. In particular, he
+ * may change it without telling us.
+ * Therefore we make a copy (or "snapshot") here.
+ */
+ aio->io_flags |= AIO_WRITING;
+#ifdef USE_MEMCPY
+ if (aio_a->shadow_data != aio->io_data) {
+ if (unlikely(aio->io_len <= 0 || aio->io_len > PAGE_SIZE))
+ XIO_ERR("implausible io_len = %d\n", aio->io_len);
+ memcpy(aio_a->shadow_data, aio->io_data, aio->io_len);
+ }
+#endif
+ aio_a->is_dirty = true;
+ aio_a->shadow_aio->is_dirty = true;
+#ifndef KEEP_UNIQUE
+ if (unlikely(aio_a->shadow_aio != aio_a))
+ XIO_ERR("something is wrong: %p != %p\n", aio_a->shadow_aio, aio_a);
+#endif
+ if (likely(!aio_a->is_hashed)) {
+ struct trans_logger_input *log_input;
+
+ log_input = brick->inputs[brick->log_input_nr];
+ aio_a->log_input = log_input;
+ atomic_inc(&log_input->log_obj_count);
+ hash_insert(brick, aio_a);
+ } else {
+ XIO_ERR("tried to hash twice\n");
+ }
+ return phase0_startio(aio_a);
+
+err:
+ XIO_ERR("cannot work\n");
+ brick_msleep(1000);
+ return false;
+}
+
+/*********************************************************************
+ * Phase 1: read original version of data.
+ * This happens _after_ phase 0, deliberately.
+ * We are explicitly dealing with old and new versions.
+ * The new version is hashed in memory all the time (such that parallel
+ * READs will see them), so we have plenty of time for getting the
+ * old version from disk somewhen later, e.g. when IO contention is low.
+ */
+
+static
+void phase1_endio(struct generic_callback *cb)
+{
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct writeback_info *wb;
+ struct trans_logger_brick *brick;
+
+ CHECK_PTR(cb, err);
+ sub_aio_a = cb->cb_private;
+ CHECK_PTR(sub_aio_a, err);
+ wb = sub_aio_a->wb;
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+
+ if (unlikely(cb->cb_error < 0)) {
+ XIO_FAT("IO error %d\n", cb->cb_error);
+ goto err;
+ }
+
+ qq_dec_flying(&brick->q_phase[1]);
+
+ banning_reset(&brick->q_phase[1].q_banning);
+
+ /* queue up for the next phase */
+ qq_wb_insert(&brick->q_phase[2], wb);
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+err:
+ XIO_FAT("hanging up....\n");
+out_return:;
+}
+
+static void phase3_endio(struct generic_callback *cb);
+
+static bool phase3_startio(struct writeback_info *wb);
+
+static
+bool phase1_startio(struct trans_logger_aio_aspect *orig_aio_a)
+{
+ struct aio_object *orig_aio;
+ struct trans_logger_brick *brick;
+ struct writeback_info *wb = NULL;
+
+ CHECK_PTR(orig_aio_a, err);
+ orig_aio = orig_aio_a->object;
+ CHECK_PTR(orig_aio, err);
+ brick = orig_aio_a->my_brick;
+ CHECK_PTR(brick, err);
+
+ if (orig_aio_a->is_collected)
+ goto done;
+ if (!orig_aio_a->is_hashed)
+ goto done;
+
+ wb = make_writeback(brick, orig_aio->io_pos, orig_aio->io_len);
+ if (unlikely(!wb))
+ goto collision;
+
+ if (unlikely(list_empty(&wb->w_sub_write_list))) {
+ XIO_ERR("sub_write_list is empty, orig pos = %lld len = %d (collected=%d), extended pos = %lld len = %d\n",
+ orig_aio->io_pos,
+ orig_aio->io_len,
+ (int)orig_aio_a->is_collected,
+ wb->w_pos,
+ wb->w_len);
+ goto err;
+ }
+
+ wb->read_endio = phase1_endio;
+ wb->write_endio = phase3_endio;
+ atomic_set(&wb->w_sub_log_count, atomic_read(&wb->w_sub_read_count));
+
+ if (brick->log_reads) {
+ qq_inc_flying(&brick->q_phase[1]);
+ fire_writeback(&wb->w_sub_read_list, false);
+ } else { /* shortcut */
+#ifndef SHORTCUT_1_to_3
+ qq_wb_insert(&brick->q_phase[3], wb);
+ wake_up_interruptible_all(&brick->worker_event);
+#else
+ return phase3_startio(wb);
+#endif
+ }
+
+done:
+ return true;
+
+err:
+ if (wb)
+ free_writeback(wb);
+collision:
+ return false;
+}
+
+/*********************************************************************
+ * Phase 2: log the old disk version.
+ */
+
+static inline
+void _phase2_endio(struct writeback_info *wb)
+{
+ struct trans_logger_brick *brick = wb->w_brick;
+
+ /* queue up for the next phase */
+ qq_wb_insert(&brick->q_phase[3], wb);
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+out_return:;
+}
+
+static
+void phase2_endio(void *private, int error)
+{
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct trans_logger_brick *brick;
+ struct writeback_info *wb;
+
+ sub_aio_a = private;
+ CHECK_PTR(sub_aio_a, err);
+ wb = sub_aio_a->wb;
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+
+ qq_dec_flying(&brick->q_phase[2]);
+
+ if (unlikely(error < 0)) {
+ XIO_FAT("IO error %d\n", error);
+ goto err; /* FIXME: this leads to hanging requests. do better. */
+ }
+
+ CHECK_ATOMIC(&wb->w_sub_log_count, 1);
+ if (atomic_dec_and_test(&wb->w_sub_log_count)) {
+ banning_reset(&brick->q_phase[2].q_banning);
+ _phase2_endio(wb);
+ }
+ goto out_return;
+err:
+ XIO_FAT("hanging up....\n");
+out_return:;
+}
+
+static
+bool _phase2_startio(struct trans_logger_aio_aspect *sub_aio_a)
+{
+ struct aio_object *sub_aio = NULL;
+ struct writeback_info *wb;
+ struct trans_logger_input *input;
+ struct trans_logger_brick *brick;
+ struct log_status *logst;
+ void *data;
+ bool ok;
+
+ CHECK_PTR(sub_aio_a, err);
+ sub_aio = sub_aio_a->object;
+ CHECK_PTR(sub_aio, err);
+ wb = sub_aio_a->wb;
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+ input = sub_aio_a->log_input;
+ CHECK_PTR(input, err);
+ logst = &input->logst;
+ logst->do_crc = trans_logger_do_crc;
+
+ {
+ struct log_header l = {
+ .l_stamp = sub_aio_a->stamp,
+ .l_pos = sub_aio->io_pos,
+ .l_len = sub_aio->io_len,
+ .l_code = CODE_WRITE_OLD,
+ };
+ data = log_reserve(logst, &l);
+ }
+
+ if (unlikely(!data))
+ goto err;
+
+ memcpy(data, sub_aio->io_data, sub_aio->io_len);
+
+ ok = log_finalize(logst, sub_aio->io_len, phase2_endio, sub_aio_a);
+ if (unlikely(!ok))
+ goto err;
+
+ qq_inc_flying(&brick->q_phase[2]);
+
+ return true;
+
+err:
+ XIO_FAT("cannot log old data, pos = %lld len = %d\n",
+ sub_aio ? sub_aio->io_pos : 0,
+ sub_aio ? sub_aio->io_len : 0);
+ return false;
+}
+
+static
+bool phase2_startio(struct writeback_info *wb)
+{
+ struct trans_logger_brick *brick;
+ bool ok = true;
+
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+
+ if (brick->log_reads && atomic_read(&wb->w_sub_log_count) > 0) {
+ struct list_head *start;
+ struct list_head *tmp;
+
+ start = &wb->w_sub_read_list;
+ for (tmp = start->next; tmp != start; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+
+ sub_aio_a = container_of(tmp, struct trans_logger_aio_aspect, sub_head);
+ sub_aio = sub_aio_a->object;
+
+ if (!_phase2_startio(sub_aio_a))
+ ok = false;
+ }
+ wake_up_interruptible_all(&brick->worker_event);
+ } else {
+ _phase2_endio(wb);
+ }
+ return ok;
+err:
+ return false;
+}
+
+/*********************************************************************
+ * Phase 3: overwrite old disk version with new version.
+ */
+
+static
+void phase3_endio(struct generic_callback *cb)
+{
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct writeback_info *wb;
+ struct trans_logger_brick *brick;
+
+ CHECK_PTR(cb, err);
+ sub_aio_a = cb->cb_private;
+ CHECK_PTR(sub_aio_a, err);
+ wb = sub_aio_a->wb;
+ CHECK_PTR(wb, err);
+ brick = wb->w_brick;
+ CHECK_PTR(brick, err);
+
+ if (unlikely(cb->cb_error < 0)) {
+ XIO_FAT("IO error %d\n", cb->cb_error);
+ goto err;
+ }
+
+ hash_put_all(brick, &wb->w_collect_list);
+
+ qq_dec_flying(&brick->q_phase[3]);
+ atomic_inc(&brick->total_writeback_cluster_count);
+
+ free_writeback(wb);
+
+ banning_reset(&brick->q_phase[3].q_banning);
+
+ wake_up_interruptible_all(&brick->worker_event);
+
+ goto out_return;
+err:
+ XIO_FAT("hanging up....\n");
+out_return:;
+}
+
+static
+bool phase3_startio(struct writeback_info *wb)
+{
+ struct list_head *start = &wb->w_sub_read_list;
+ struct list_head *tmp;
+
+ /* Cleanup read requests (if they exist from previous phases)
+ */
+ while ((tmp = start->next) != start) {
+ struct trans_logger_aio_aspect *sub_aio_a;
+ struct aio_object *sub_aio;
+ struct trans_logger_input *sub_input;
+
+ list_del_init(tmp);
+
+ sub_aio_a = container_of(tmp, struct trans_logger_aio_aspect, sub_head);
+ sub_aio = sub_aio_a->object;
+ sub_input = sub_aio_a->my_input;
+
+ GENERIC_INPUT_CALL(sub_input, aio_put, sub_aio);
+ }
+
+ update_writeback_info(wb);
+
+ /* Start writeback IO
+ */
+ qq_inc_flying(&wb->w_brick->q_phase[3]);
+ fire_writeback(&wb->w_sub_write_list, true);
+ return true;
+}
+
+/*********************************************************************
+ * The logger thread.
+ * There is only a single instance, dealing with all requests in parallel.
+ */
+
+static
+int run_aio_queue(struct logger_queue *q,
+ bool (*startio)(struct trans_logger_aio_aspect *sub_aio_a),
+ int max,
+ bool do_limit)
+{
+ struct trans_logger_brick *brick = q->q_brick;
+ int total_len = 0;
+ bool found = false;
+ bool ok;
+ int res = 0;
+
+ do {
+ struct trans_logger_aio_aspect *aio_a;
+
+ aio_a = qq_aio_fetch(q);
+ if (!aio_a)
+ goto done;
+
+ if (do_limit && likely(aio_a->object))
+ total_len += aio_a->object->io_len;
+
+ ok = startio(aio_a);
+ if (unlikely(!ok)) {
+ qq_aio_pushback(q, aio_a);
+ goto done;
+ }
+ res++;
+ found = true;
+ __trans_logger_io_put(aio_a->my_brick, aio_a);
+ } while (--max > 0);
+
+done:
+ if (found) {
+ rate_limit(&global_writeback.limiter, (total_len - 1) / 1024 + 1);
+ wake_up_interruptible_all(&brick->worker_event);
+ }
+ return res;
+}
+
+static
+int run_wb_queue(struct logger_queue *q, bool (*startio)(struct writeback_info *wb), int max)
+{
+ struct trans_logger_brick *brick = q->q_brick;
+ int total_len = 0;
+ bool found = false;
+ bool ok;
+ int res = 0;
+
+ do {
+ struct writeback_info *wb;
+
+ wb = qq_wb_fetch(q);
+ if (!wb)
+ goto done;
+
+ total_len += wb->w_len;
+
+ ok = startio(wb);
+ if (unlikely(!ok)) {
+ qq_wb_pushback(q, wb);
+ goto done;
+ }
+ res++;
+ found = true;
+ } while (--max > 0);
+
+done:
+ if (found) {
+ rate_limit(&global_writeback.limiter, (total_len - 1) / 1024 + 1);
+ wake_up_interruptible_all(&brick->worker_event);
+ }
+ return res;
+}
+
+/* Ranking tables.
+ */
+static
+struct rank_info float_queue_rank_log[] = {
+ { 0, 0 },
+ { 1, 100 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info float_queue_rank_io[] = {
+ { 0, 0 },
+ { 1, 1 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info float_fly_rank_log[] = {
+ { 0, 0 },
+ { 1, 1 },
+ { 32, 10 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info float_fly_rank_io[] = {
+ { 0, 0 },
+ { 1, 10 },
+ { 2, -10 },
+ { 10000, -200 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info nofloat_queue_rank_log[] = {
+ { 0, 0 },
+ { 1, 10 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info nofloat_queue_rank_io[] = {
+ { 0, 0 },
+ { 1, 10 },
+ { 100, 100 },
+ { RKI_DUMMY }
+};
+
+#define nofloat_fly_rank_log float_fly_rank_log
+
+static
+struct rank_info nofloat_fly_rank_io[] = {
+ { 0, 0 },
+ { 1, 10 },
+ { 128, 8 },
+ { 129, -200 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info *queue_ranks[2][LOGGER_QUEUES] = {
+ [0] = {
+ [0] = float_queue_rank_log,
+ [1] = float_queue_rank_io,
+ [2] = float_queue_rank_io,
+ [3] = float_queue_rank_io,
+ },
+ [1] = {
+ [0] = nofloat_queue_rank_log,
+ [1] = nofloat_queue_rank_io,
+ [2] = nofloat_queue_rank_io,
+ [3] = nofloat_queue_rank_io,
+ },
+};
+static
+struct rank_info *fly_ranks[2][LOGGER_QUEUES] = {
+ [0] = {
+ [0] = float_fly_rank_log,
+ [1] = float_fly_rank_io,
+ [2] = float_fly_rank_io,
+ [3] = float_fly_rank_io,
+ },
+ [1] = {
+ [0] = nofloat_fly_rank_log,
+ [1] = nofloat_fly_rank_io,
+ [2] = nofloat_fly_rank_io,
+ [3] = nofloat_fly_rank_io,
+ },
+};
+
+static
+struct rank_info extra_rank_aio_flying[] = {
+ { 0, 0 },
+ { 1, 10 },
+ { 16, 30 },
+ { 31, 0 },
+ { 32, -200 },
+ { RKI_DUMMY }
+};
+
+static
+struct rank_info global_rank_aio_flying[] = {
+ { 0, 0 },
+ { 63, 0 },
+ { 64, -200 },
+ { RKI_DUMMY }
+};
+
+static
+int _do_ranking(struct trans_logger_brick *brick, struct rank_data rkd[])
+{
+ int res;
+ int i;
+ int floating_mode;
+ int aio_flying;
+ bool delay_callers;
+
+ ranking_start(rkd, LOGGER_QUEUES);
+
+ /* check the memory situation... */
+ delay_callers = false;
+ floating_mode = 1;
+ if (brick_global_memlimit >= 1024) {
+ int global_mem_used = atomic64_read(&global_mshadow_used) / 1024;
+
+ trans_logger_mem_usage = global_mem_used;
+
+ floating_mode = (global_mem_used < brick_global_memlimit / 2) ? 0 : 1;
+
+ if (global_mem_used >= brick_global_memlimit)
+ delay_callers = true;
+
+ } else if (brick->shadow_mem_limit >= 8) {
+ int local_mem_used = atomic64_read(&brick->shadow_mem_used) / 1024;
+
+ floating_mode = (local_mem_used < brick->shadow_mem_limit / 2) ? 0 : 1;
+
+ if (local_mem_used >= brick->shadow_mem_limit)
+ delay_callers = true;
+ }
+ if (delay_callers) {
+ if (!brick->delay_callers) {
+ brick->delay_callers = true;
+ atomic_inc(&brick->total_delay_count);
+ }
+ } else if (brick->delay_callers) {
+ brick->delay_callers = false;
+ wake_up_interruptible(&brick->caller_event);
+ }
+
+ /* global limit for flying aios */
+ ranking_compute(&rkd[0], global_rank_aio_flying, atomic_read(&global_aio_flying));
+
+ /* local limit for flying aios */
+ aio_flying = 0;
+ for (i = TL_INPUT_LOG1; i <= TL_INPUT_LOG2; i++) {
+ struct trans_logger_input *input = brick->inputs[i];
+
+ aio_flying += atomic_read(&input->logst.aio_flying);
+ }
+
+ /* obey the basic rules... */
+ for (i = 0; i < LOGGER_QUEUES; i++) {
+ int queued = atomic_read(&brick->q_phase[i].q_queued);
+ int flying;
+
+ /* This must come first.
+ * When a queue is empty, you must not credit any positive points.
+ * Otherwise, (almost) infinite selection of untreatable
+ * queues may occur.
+ */
+ if (queued <= 0)
+ continue;
+
+ if (banning_is_hit(&brick->q_phase[i].q_banning))
+ break;
+
+ if (i == 0) {
+ /* limit aio IO parallelism on transaction log */
+ ranking_compute(&rkd[0], extra_rank_aio_flying, aio_flying);
+ } else if (i == 1 && !floating_mode) {
+ struct trans_logger_brick *leader;
+ int lim;
+
+ if (!aio_flying && atomic_read(&brick->q_phase[0].q_queued) > 0)
+ break;
+
+ leader = elect_leader(&global_writeback);
+ if (leader != brick)
+ break;
+
+ if (banning_is_hit(&xio_global_ban))
+ break;
+
+ lim = rate_limit(&global_writeback.limiter, 0);
+ if (lim > 0)
+ break;
+ }
+
+ ranking_compute(&rkd[i], queue_ranks[floating_mode][i], queued);
+
+ flying = atomic_read(&brick->q_phase[i].q_flying);
+
+ ranking_compute(&rkd[i], fly_ranks[floating_mode][i], flying);
+ }
+
+ /* finalize it */
+ ranking_stop(rkd, LOGGER_QUEUES);
+
+ res = ranking_select(rkd, LOGGER_QUEUES);
+
+ return res;
+}
+
+static
+void _init_input(struct trans_logger_input *input, loff_t start_pos, loff_t end_pos)
+{
+ struct trans_logger_brick *brick = input->brick;
+ struct log_status *logst = &input->logst;
+
+ init_logst(logst, (void *)input, start_pos, end_pos);
+ logst->signal_event = &brick->worker_event;
+ logst->align_size = CONF_TRANS_ALIGN;
+ logst->chunk_size = CONF_TRANS_CHUNKSIZE;
+ logst->max_size = CONF_TRANS_MAX_AIO_SIZE;
+
+ input->inf.inf_min_pos = start_pos;
+ input->inf.inf_max_pos = end_pos;
+ get_lamport(&input->inf.inf_max_pos_stamp);
+ memcpy(&input->inf.inf_min_pos_stamp, &input->inf.inf_max_pos_stamp, sizeof(input->inf.inf_min_pos_stamp));
+
+ logst->log_pos = start_pos;
+ input->inf.inf_log_pos = start_pos;
+ input->inf_last_jiffies = jiffies;
+ input->inf.inf_is_replaying = false;
+ input->inf.inf_is_logging = false;
+
+ input->is_operating = true;
+}
+
+static
+void _init_inputs(struct trans_logger_brick *brick, bool is_first)
+{
+ struct trans_logger_input *input;
+ int old_nr = brick->old_input_nr;
+ int log_nr = brick->log_input_nr;
+ int new_nr = brick->new_input_nr;
+
+ if (!is_first &&
+ (new_nr == log_nr ||
+ log_nr != old_nr)) {
+ goto done;
+ }
+ if (unlikely(new_nr < TL_INPUT_LOG1 || new_nr > TL_INPUT_LOG2)) {
+ XIO_ERR("bad new_input_nr = %d\n", new_nr);
+ goto done;
+ }
+
+ input = brick->inputs[new_nr];
+ CHECK_PTR(input, done);
+
+ if (input->is_operating || !input->connect)
+ goto done;
+
+ down(&input->inf_mutex);
+
+ _init_input(input, 0, 0);
+ input->inf.inf_is_logging = is_first;
+
+ /* from now on, new requests should go to the new input */
+ brick->log_input_nr = new_nr;
+ XIO_INF("switched over to new logfile %d (old = %d)\n", new_nr, old_nr);
+
+ /* Flush the old log buffer and update its symlinks.
+ * Notice: for some short time, _both_ logfiles may grow
+ * due to (harmless) races with log_flush().
+ */
+ if (likely(!is_first)) {
+ struct trans_logger_input *other_input = brick->inputs[old_nr];
+
+ down(&other_input->inf_mutex);
+ log_flush(&other_input->logst);
+ _inf_callback(other_input, true);
+ up(&other_input->inf_mutex);
+ }
+
+ _inf_callback(input, true);
+
+ up(&input->inf_mutex);
+done:;
+}
+
+static
+int _nr_flying_inputs(struct trans_logger_brick *brick)
+{
+ int count = 0;
+ int i;
+
+ for (i = TL_INPUT_LOG1; i <= TL_INPUT_LOG2; i++) {
+ struct trans_logger_input *input = brick->inputs[i];
+ struct log_status *logst = &input->logst;
+
+ if (input->is_operating)
+ count += logst->count;
+ }
+ return count;
+}
+
+static
+void _flush_inputs(struct trans_logger_brick *brick)
+{
+ int i;
+
+ for (i = TL_INPUT_LOG1; i <= TL_INPUT_LOG2; i++) {
+ struct trans_logger_input *input = brick->inputs[i];
+ struct log_status *logst = &input->logst;
+
+ if (input->is_operating && logst->count > 0) {
+ atomic_inc(&brick->total_flush_count);
+ log_flush(logst);
+ }
+ }
+}
+
+static
+void _exit_inputs(struct trans_logger_brick *brick, bool force)
+{
+ int i;
+
+ for (i = TL_INPUT_LOG1; i <= TL_INPUT_LOG2; i++) {
+ struct trans_logger_input *input = brick->inputs[i];
+ struct log_status *logst = &input->logst;
+
+ if (input->is_operating &&
+ (force || !input->connect)) {
+ bool old_replaying = input->inf.inf_is_replaying;
+ bool old_logging = input->inf.inf_is_logging;
+
+ XIO_DBG("cleaning up input %d (log = %d old = %d), old_replaying = %d old_logging = %d\n",
+ i,
+ brick->log_input_nr,
+ brick->old_input_nr,
+ old_replaying,
+ old_logging);
+ exit_logst(logst);
+ /* no locking here: we should be the only thread doing this. */
+ _inf_callback(input, true);
+ input->inf_last_jiffies = 0;
+ input->inf.inf_is_replaying = false;
+ input->inf.inf_is_logging = false;
+ input->is_operating = false;
+ if (i == brick->old_input_nr && i != brick->log_input_nr) {
+ struct trans_logger_input *other_input = brick->inputs[brick->log_input_nr];
+
+ down(&other_input->inf_mutex);
+ brick->old_input_nr = brick->log_input_nr;
+ other_input->inf.inf_is_replaying = old_replaying;
+ other_input->inf.inf_is_logging = old_logging;
+ _inf_callback(other_input, true);
+ up(&other_input->inf_mutex);
+ }
+ }
+ }
+}
+
+/* Performance-critical:
+ * Calling log_flush() too often may result in
+ * increased overhead (and thus in lower throughput).
+ * Call it only when the IO scheduler need not do anything else.
+ * OTOH, calling it too seldom may hold back
+ * IO completion for the end user for too long time.
+ *
+ * Be careful to flush any leftovers in the log buffer, at least after
+ * some short delay.
+ *
+ * Description of flush_mode:
+ * 0 = flush unconditionally
+ * 1 = flush only when nothing can be appended to the transaction log
+ * 2 = see 1 && flush only when the user is waiting for an answer
+ * 3 = see 1 && not 2 && flush only when there is no other activity (background mode)
+ * Notice: 3 makes only sense for leftovers where the user is _not_ waiting for
+ */
+static inline
+void flush_inputs(struct trans_logger_brick *brick, int flush_mode)
+{
+ if (flush_mode < 1 ||
+ /* there is nothing to append any more */
+ (atomic_read(&brick->q_phase[0].q_queued) <= 0 &&
+ /* and the user is waiting for an answer */
+ (flush_mode < 2 ||
+ atomic_read(&brick->log_fly_count) > 0 ||
+ /* else flush any leftovers in background, when there is no writeback activity */
+ (flush_mode == 3 &&
+ atomic_read(&brick->q_phase[1].q_flying) + atomic_read(&brick->q_phase[3].q_flying) <= 0))))
+ _flush_inputs(brick);
+}
+
+static
+void trans_logger_log(struct trans_logger_brick *brick)
+{
+ struct rank_data rkd[LOGGER_QUEUES] = {};
+ long long old_jiffies = jiffies;
+ long long work_jiffies = jiffies;
+ int interleave = 0;
+ int nr_flying;
+
+ brick->replay_code = 0; /* indicates "running" */
+ brick->disk_io_error = 0;
+
+ _init_inputs(brick, true);
+
+ xio_set_power_on_led((void *)brick, true);
+
+ while (!brick_thread_should_stop() || _congested(brick)) {
+ int winner;
+ int nr;
+
+ wait_event_interruptible_timeout(
+ brick->worker_event,
+ ({
+ winner = _do_ranking(brick, rkd);
+ if (winner < 0) { /* no more work to do */
+ int flush_mode = 2 - ((int)(jiffies - work_jiffies)) / (HZ * 2);
+
+ flush_inputs(brick, flush_mode);
+ interleave = 0;
+ } else { /* reset the timer whenever something is to do */
+ work_jiffies = jiffies;
+ }
+ winner >= 0;
+ }),
+ HZ / 10);
+
+ atomic_inc(&brick->total_round_count);
+
+ if (brick->cease_logging)
+ brick->stopped_logging = true;
+ else if (brick->stopped_logging && !_congested(brick))
+ brick->stopped_logging = false;
+
+ _init_inputs(brick, false);
+
+ switch (winner) {
+ case 0:
+ interleave = 0;
+ nr = run_aio_queue(&brick->q_phase[0],
+ prep_phase_startio,
+ brick->q_phase[0].q_batchlen,
+ true);
+ goto done;
+ case 1:
+ if (interleave >= trans_logger_max_interleave && trans_logger_max_interleave >= 0) {
+ interleave = 0;
+ flush_inputs(brick, 3);
+ }
+ nr = run_aio_queue(&brick->q_phase[1], phase1_startio, brick->q_phase[1].q_batchlen, true);
+ interleave += nr;
+ goto done;
+ case 2:
+ interleave = 0;
+ nr = run_wb_queue(&brick->q_phase[2], phase2_startio, brick->q_phase[2].q_batchlen);
+ goto done;
+ case 3:
+ if (interleave >= trans_logger_max_interleave && trans_logger_max_interleave >= 0) {
+ interleave = 0;
+ flush_inputs(brick, 3);
+ }
+ nr = run_wb_queue(&brick->q_phase[3], phase3_startio, brick->q_phase[3].q_batchlen);
+ interleave += nr;
+done:
+ if (unlikely(nr <= 0)) {
+ /* This should not happen!
+ * However, in error situations, the ranking
+ * algorithm cannot foresee anything.
+ */
+ brick->q_phase[winner].no_progress_count++;
+ banning_hit(&brick->q_phase[winner].q_banning, 10000);
+ flush_inputs(brick, 0);
+ }
+ ranking_select_done(rkd, winner, nr);
+ break;
+
+ default:
+ break;
+ }
+
+ /* Update symlinks even during pauses.
+ */
+ if (winner < 0 && ((long long)jiffies) - old_jiffies >= HZ) {
+ int i;
+
+ old_jiffies = jiffies;
+ for (i = TL_INPUT_LOG1; i <= TL_INPUT_LOG2; i++) {
+ struct trans_logger_input *input = brick->inputs[i];
+
+ down(&input->inf_mutex);
+ _inf_callback(input, false);
+ up(&input->inf_mutex);
+ }
+ }
+
+ _exit_inputs(brick, false);
+ }
+
+ for (;;) {
+ _exit_inputs(brick, true);
+ nr_flying = _nr_flying_inputs(brick);
+ if (nr_flying <= 0)
+ break;
+ XIO_INF("%d inputs are operating\n", nr_flying);
+ brick_msleep(1000);
+ }
+}
+
+/***************************** log replay *****************************/
+
+static
+void replay_endio(struct generic_callback *cb)
+{
+ struct trans_logger_aio_aspect *aio_a = cb->cb_private;
+ struct trans_logger_brick *brick;
+ bool ok;
+ unsigned long flags;
+
+ LAST_CALLBACK(cb);
+ CHECK_PTR(aio_a, err);
+ brick = aio_a->my_brick;
+ CHECK_PTR(brick, err);
+
+ if (unlikely(cb->cb_error < 0)) {
+ brick->disk_io_error = cb->cb_error;
+ XIO_ERR("IO error = %d\n", cb->cb_error);
+ }
+
+ spin_lock_irqsave(&brick->replay_lock, flags);
+ ok = !list_empty(&aio_a->replay_head);
+ list_del_init(&aio_a->replay_head);
+ spin_unlock_irqrestore(&brick->replay_lock, flags);
+
+ if (likely(ok))
+ atomic_dec(&brick->replay_count);
+ else
+ XIO_ERR("callback with empty replay_head (replay_count=%d)\n", atomic_read(&brick->replay_count));
+ wake_up_interruptible_all(&brick->worker_event);
+ goto out_return;
+err:
+ XIO_FAT("cannot handle replay IO\n");
+out_return:;
+}
+
+static
+bool _has_conflict(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *aio_a)
+{
+ struct aio_object *aio = aio_a->object;
+ struct list_head *tmp;
+ bool res = false;
+ unsigned long flags;
+
+/**/
+
+ spin_lock_irqsave(&brick->replay_lock, flags);
+
+ for (tmp = brick->replay_list.next; tmp != &brick->replay_list; tmp = tmp->next) {
+ struct trans_logger_aio_aspect *tmp_a;
+ struct aio_object *tmp_aio;
+
+ tmp_a = container_of(tmp, struct trans_logger_aio_aspect, replay_head);
+ tmp_aio = tmp_a->object;
+ if (tmp_aio->io_pos + tmp_aio->io_len > aio->io_pos && tmp_aio->io_pos < aio->io_pos + aio->io_len) {
+ res = true;
+ break;
+ }
+ }
+
+ spin_unlock_irqrestore(&brick->replay_lock, flags);
+ return res;
+}
+
+static
+void wait_replay(struct trans_logger_brick *brick, struct trans_logger_aio_aspect *aio_a)
+{
+ const int max = 512; /* limit parallelism somewhat */
+ int conflicts = 0;
+ bool ok = false;
+ bool was_empty;
+ unsigned long flags;
+
+ wait_event_interruptible_timeout(brick->worker_event,
+ atomic_read(&brick->replay_count) < max
+ && (_has_conflict(brick, aio_a) ? conflicts++ : (ok = true), ok),
+ 60 * HZ);
+
+ atomic_inc(&brick->total_replay_count);
+ if (conflicts)
+ atomic_inc(&brick->total_replay_conflict_count);
+
+ spin_lock_irqsave(&brick->replay_lock, flags);
+ was_empty = !!list_empty(&aio_a->replay_head);
+ if (likely(was_empty))
+ atomic_inc(&brick->replay_count);
+ else
+ list_del(&aio_a->replay_head);
+ list_add(&aio_a->replay_head, &brick->replay_list);
+ spin_unlock_irqrestore(&brick->replay_lock, flags);
+
+ if (unlikely(!was_empty)) {
+ XIO_ERR("replay_head was already used (ok=%d, conflicts=%d, replay_count=%d)\n",
+ ok,
+ conflicts,
+ atomic_read(&brick->replay_count));
+ }
+}
+
+static
+int replay_data(struct trans_logger_brick *brick, loff_t pos, void *buf, int len)
+{
+ struct trans_logger_input *input = brick->inputs[TL_INPUT_WRITEBACK];
+ int status;
+
+ if (!input->connect)
+ input = brick->inputs[TL_INPUT_READ];
+
+ /* TODO for better efficiency:
+ * Instead of starting IO here, just put the data into the hashes
+ * and queues such that ordinary IO will be corrected.
+ * Writeback will be lazy then.
+ * The switch infrastructure must be changed before this
+ * becomes possible.
+ */
+#ifdef REPLAY_DATA
+ while (len > 0) {
+ struct aio_object *aio;
+ struct trans_logger_aio_aspect *aio_a;
+
+ status = -ENOMEM;
+ aio = trans_logger_alloc_aio(brick);
+ aio_a = trans_logger_aio_get_aspect(brick, aio);
+ CHECK_PTR(aio_a, done);
+ CHECK_ASPECT(aio_a, aio, done);
+
+ aio->io_pos = pos;
+ aio->io_data = NULL;
+ aio->io_len = len;
+ aio->io_may_write = WRITE;
+ aio->io_rw = WRITE;
+
+ status = GENERIC_INPUT_CALL(input, aio_get, aio);
+ if (unlikely(status < 0)) {
+ XIO_ERR("cannot get aio, status = %d\n", status);
+ goto done;
+ }
+ if (unlikely(!aio->io_data)) {
+ status = -ENOMEM;
+ XIO_ERR("cannot get aio, status = %d\n", status);
+ goto done;
+ }
+ if (unlikely(aio->io_len <= 0 || aio->io_len > len)) {
+ status = -EINVAL;
+ XIO_ERR("bad aio len = %d (requested = %d)\n", aio->io_len, len);
+ goto done;
+ }
+
+ wait_replay(brick, aio_a);
+
+ memcpy(aio->io_data, buf, aio->io_len);
+
+ SETUP_CALLBACK(aio, replay_endio, aio_a);
+ aio_a->my_brick = brick;
+
+ GENERIC_INPUT_CALL(input, aio_io, aio);
+
+ if (unlikely(aio->io_len <= 0)) {
+ status = -EINVAL;
+ XIO_ERR("bad aio len = %d (requested = %d)\n", aio->io_len, len);
+ goto done;
+ }
+
+ pos += aio->io_len;
+ buf += aio->io_len;
+ len -= aio->io_len;
+
+ GENERIC_INPUT_CALL(input, aio_put, aio);
+ }
+#endif
+ status = 0;
+done:
+ return status;
+}
+
+static
+void trans_logger_replay(struct trans_logger_brick *brick)
+{
+ struct trans_logger_input *input = brick->inputs[brick->log_input_nr];
+ struct log_header lh = {};
+ loff_t start_pos;
+ loff_t end_pos;
+ loff_t finished_pos = -1;
+ loff_t new_finished_pos = -1;
+ long long old_jiffies = jiffies;
+ int nr_flying;
+ int backoff = 0;
+ int status = 0;
+
+ brick->replay_code = 0; /* indicates "running" */
+ brick->disk_io_error = 0;
+
+ start_pos = brick->replay_start_pos;
+ end_pos = brick->replay_end_pos;
+ brick->replay_current_pos = start_pos;
+
+ _init_input(input, start_pos, end_pos);
+
+ input->inf.inf_min_pos = start_pos;
+ input->inf.inf_max_pos = end_pos;
+ input->inf.inf_log_pos = end_pos;
+ input->inf.inf_is_replaying = true;
+ input->inf.inf_is_logging = false;
+
+ XIO_INF("starting replay from %lld to %lld\n", start_pos, end_pos);
+
+ xio_set_power_on_led((void *)brick, true);
+
+ for (;;) {
+ void *buf = NULL;
+ int len = 0;
+
+ if (brick_thread_should_stop() ||
+ (!brick->continuous_replay_mode && finished_pos >= brick->replay_end_pos)) {
+ status = 0; /* treat as EOF */
+ break;
+ }
+
+ status = log_read(&input->logst, false, &lh, &buf, &len);
+
+ new_finished_pos = input->logst.log_pos + input->logst.offset;
+ XIO_RPL("read %lld %lld\n", finished_pos, new_finished_pos);
+
+ if (status == -EAGAIN) {
+ loff_t remaining = brick->replay_end_pos - new_finished_pos;
+
+ XIO_DBG("got -EAGAIN, remaining = %lld\n", remaining);
+ if (brick->replay_tolerance > 0 && remaining < brick->replay_tolerance) {
+ XIO_WRN("logfile is truncated at position %lld (end_pos = %lld, remaining = %lld, tolerance = %d)\n",
+ new_finished_pos,
+ brick->replay_end_pos,
+ remaining,
+ brick->replay_tolerance);
+ finished_pos = new_finished_pos;
+ brick->replay_code = status;
+ break;
+ }
+ brick_msleep(backoff);
+ if (backoff < trans_logger_replay_timeout * 1000) {
+ backoff += 100;
+ } else {
+ XIO_WRN("logfile replay not possible at position %lld (end_pos = %lld, remaining = %lld), please check/repair your logfile in userspace by some tool!\n",
+ new_finished_pos,
+ brick->replay_end_pos,
+ remaining);
+ brick->replay_code = status;
+ break;
+ }
+ continue;
+ }
+ if (unlikely(status < 0)) {
+ brick->replay_code = status;
+ XIO_WRN("cannot read logfile data, status = %d\n", status);
+ break;
+ }
+
+ if ((!status && len <= 0) ||
+ new_finished_pos > brick->replay_end_pos) { /* EOF -> wait until brick_thread_should_stop() */
+ XIO_DBG("EOF at %lld (old = %lld, end_pos = %lld)\n",
+ new_finished_pos,
+ finished_pos,
+ brick->replay_end_pos);
+ if (!brick->continuous_replay_mode) {
+ /* notice: finished_pos remains at old value here! */
+ break;
+ }
+ brick_msleep(1000);
+ continue;
+ }
+
+ if (lh.l_code != CODE_WRITE_NEW) {
+ /* ignore other records silently */;
+ } else if (unlikely(brick->disk_io_error)) {
+ status = brick->disk_io_error;
+ brick->replay_code = status;
+ XIO_ERR("IO error %d\n", status);
+ break;
+ } else if (likely(buf && len)) {
+ if (brick->replay_limiter)
+ rate_limit_sleep(brick->replay_limiter, (len - 1) / 1024 + 1);
+ status = replay_data(brick, lh.l_pos, buf, len);
+ XIO_RPL("replay %lld %lld (pos=%lld status=%d)\n",
+ finished_pos,
+ new_finished_pos,
+ lh.l_pos,
+ status);
+ if (unlikely(status < 0)) {
+ brick->replay_code = status;
+ XIO_ERR("cannot replay data at pos = %lld len = %d, status = %d\n",
+ lh.l_pos,
+ len,
+ status);
+ break;
+ } else {
+ finished_pos = new_finished_pos;
+ }
+ }
+
+ /* do this _after_ any opportunities for errors... */
+ if ((atomic_read(&brick->replay_count) <= 0 ||
+ ((long long)jiffies) - old_jiffies >= HZ * 3) &&
+ finished_pos >= 0) {
+ /* for safety, wait until the IO queue has drained. */
+ wait_event_interruptible_timeout(brick->worker_event,
+ atomic_read(&brick->replay_count) <= 0,
+ 30 * HZ);
+
+ if (unlikely(brick->disk_io_error)) {
+ status = brick->disk_io_error;
+ brick->replay_code = status;
+ XIO_ERR("IO error %d\n", status);
+ break;
+ }
+
+ down(&input->inf_mutex);
+ input->inf.inf_min_pos = finished_pos;
+ get_lamport(&input->inf.inf_min_pos_stamp);
+ old_jiffies = jiffies;
+ _inf_callback(input, false);
+ up(&input->inf_mutex);
+ }
+ _exit_inputs(brick, false);
+ }
+
+ XIO_INF("waiting for finish...\n");
+
+ wait_event_interruptible_timeout(brick->worker_event, atomic_read(&brick->replay_count) <= 0, 60 * HZ);
+
+ if (unlikely(finished_pos > brick->replay_end_pos)) {
+ XIO_ERR("finished_pos too large: %lld + %d = %lld > %lld\n",
+ input->logst.log_pos,
+ input->logst.offset,
+ finished_pos,
+ brick->replay_end_pos);
+ }
+
+ if (finished_pos >= 0 && !brick->disk_io_error) {
+ input->inf.inf_min_pos = finished_pos;
+ brick->replay_current_pos = finished_pos;
+ }
+
+ get_lamport(&input->inf.inf_min_pos_stamp);
+
+ if (status >= 0 && finished_pos == brick->replay_end_pos) {
+ XIO_INF("replay finished at %lld\n", finished_pos);
+ brick->replay_code = 1;
+ } else if (status == -EAGAIN && finished_pos + brick->replay_tolerance > brick->replay_end_pos) {
+ XIO_INF("TOLERANCE: logfile is incomplete at %lld (of %lld)\n", finished_pos, brick->replay_end_pos);
+ brick->replay_code = 2;
+ } else if (status < 0) {
+ if (finished_pos < 0)
+ finished_pos = new_finished_pos;
+ if (finished_pos + brick->replay_tolerance > brick->replay_end_pos) {
+ XIO_INF("TOLERANCE: logfile is incomplete at %lld (of %lld), status = %d\n",
+ finished_pos,
+ brick->replay_end_pos,
+ status);
+ } else {
+ XIO_ERR("replay error %d at %lld (of %lld)\n", status, finished_pos, brick->replay_end_pos);
+ }
+ brick->replay_code = status;
+ } else {
+ XIO_INF("replay stopped prematurely at %lld (of %lld)\n", finished_pos, brick->replay_end_pos);
+ brick->replay_code = 2;
+ }
+
+ for (;;) {
+ _exit_inputs(brick, true);
+ nr_flying = _nr_flying_inputs(brick);
+ if (nr_flying <= 0)
+ break;
+ XIO_INF("%d inputs are operating\n", nr_flying);
+ brick_msleep(1000);
+ }
+
+ local_trigger();
+
+ while (!brick_thread_should_stop())
+ brick_msleep(500);
+}
+
+/************************ logger thread * switching ************************/
+
+static
+int trans_logger_thread(void *data)
+{
+ struct trans_logger_output *output = data;
+ struct trans_logger_brick *brick = output->brick;
+
+ XIO_INF("........... logger has started.\n");
+
+ if (brick->replay_mode)
+ trans_logger_replay(brick);
+ else
+ trans_logger_log(brick);
+ XIO_INF("........... logger has stopped.\n");
+ xio_set_power_on_led((void *)brick, false);
+ xio_set_power_off_led((void *)brick, true);
+ return 0;
+}
+
+static
+int trans_logger_switch(struct trans_logger_brick *brick)
+{
+ static int index;
+ struct trans_logger_output *output = brick->outputs[0];
+
+ if (brick->power.button) {
+ if (!brick->thread && brick->power.off_led) {
+ xio_set_power_off_led((void *)brick, false);
+
+ brick->thread = brick_thread_create(trans_logger_thread, output, "xio_logger%d", index++);
+ if (unlikely(!brick->thread)) {
+ XIO_ERR("cannot create logger thread\n");
+ return -ENOENT;
+ }
+ }
+ } else {
+ xio_set_power_on_led((void *)brick, false);
+ if (brick->thread) {
+ XIO_INF("stopping thread...\n");
+ brick_thread_stop(brick->thread);
+ brick->thread = NULL;
+ }
+ }
+ return 0;
+}
+
+/*************** informational * statistics **************/
+
+static
+char *trans_logger_statistics(struct trans_logger_brick *brick, int verbose)
+{
+ char *res = brick_string_alloc(1024);
+
+ snprintf(res, 1023,
+ "mode replay=%d continuous=%d replay_code=%d disk_io_error=%d log_reads=%d | cease_logging=%d stopped_logging=%d congested=%d | replay_start_pos = %lld replay_end_pos = %lld | new_input_nr = %d log_input_nr = %d (old = %d) inf_min_pos1 = %lld inf_max_pos1 = %lld inf_min_pos2 = %lld inf_max_pos2 = %lld | total hash_insert=%d hash_find=%d hash_extend=%d replay=%d replay_conflict=%d (%d%%) callbacks=%d reads=%d writes=%d flushes=%d (%d%%) wb_clusters=%d writebacks=%d (%d%%) shortcut=%d (%d%%) mshadow=%d sshadow=%d mshadow_buffered=%d sshadow_buffered=%d rounds=%d restarts=%d delays=%d phase0=%d phase1=%d phase2=%d phase3=%d | current #aios = %d shadow_mem_used=%ld/%lld replay_count=%d mshadow=%d/%d sshadow=%d hash_count=%d balance=%d/%d/%d/%d pos_count1=%d pos_count2=%d log_aios1=%d log_aios2=%d any_fly=%d log_fly=%d aio_flying1=%d aio_flying2=%d phase0=%d+%d <%d/%d> phase1=%d+%d <%d/%d> phase2=%d+%d <%d/%d> phase3=%d+%d <%d/%d>\n",
+ brick->replay_mode,
+ brick->continuous_replay_mode,
+ brick->replay_code,
+ brick->disk_io_error,
+ brick->log_reads,
+ brick->cease_logging,
+ brick->stopped_logging,
+ _congested(brick),
+ brick->replay_start_pos,
+ brick->replay_end_pos,
+ brick->new_input_nr,
+ brick->log_input_nr,
+ brick->old_input_nr,
+ brick->inputs[TL_INPUT_LOG1]->inf.inf_min_pos,
+ brick->inputs[TL_INPUT_LOG1]->inf.inf_max_pos,
+ brick->inputs[TL_INPUT_LOG2]->inf.inf_min_pos,
+ brick->inputs[TL_INPUT_LOG2]->inf.inf_max_pos,
+ atomic_read(&brick->total_hash_insert_count),
+ atomic_read(&brick->total_hash_find_count),
+ atomic_read(&brick->total_hash_extend_count),
+ atomic_read(&brick->total_replay_count),
+ atomic_read(&brick->total_replay_conflict_count),
+ atomic_read(&brick->total_replay_count) ? atomic_read(&brick->total_replay_conflict_count) * 100 / atomic_read(&brick->total_replay_count) : 0,
+ atomic_read(&brick->total_cb_count),
+ atomic_read(&brick->total_read_count),
+ atomic_read(&brick->total_write_count),
+ atomic_read(&brick->total_flush_count),
+ atomic_read(&brick->total_write_count) ? atomic_read(&brick->total_flush_count) * 100 / atomic_read(&brick->total_write_count) : 0,
+ atomic_read(&brick->total_writeback_cluster_count),
+ atomic_read(&brick->total_writeback_count),
+ atomic_read(&brick->total_writeback_cluster_count) ? atomic_read(&brick->total_writeback_count) * 100 / atomic_read(&brick->total_writeback_cluster_count) : 0,
+ atomic_read(&brick->total_shortcut_count),
+ atomic_read(&brick->total_writeback_count) ? atomic_read(&brick->total_shortcut_count) * 100 / atomic_read(&brick->total_writeback_count) : 0,
+ atomic_read(&brick->total_mshadow_count),
+ atomic_read(&brick->total_sshadow_count),
+ atomic_read(&brick->total_mshadow_buffered_count),
+ atomic_read(&brick->total_sshadow_buffered_count),
+ atomic_read(&brick->total_round_count),
+ atomic_read(&brick->total_restart_count),
+ atomic_read(&brick->total_delay_count),
+ atomic_read(&brick->q_phase[0].q_total),
+ atomic_read(&brick->q_phase[1].q_total),
+ atomic_read(&brick->q_phase[2].q_total),
+ atomic_read(&brick->q_phase[3].q_total),
+ atomic_read(&brick->aio_object_layout.alloc_count),
+ atomic64_read(&brick->shadow_mem_used) / 1024,
+ brick_global_memlimit,
+ atomic_read(&brick->replay_count),
+ atomic_read(&brick->mshadow_count),
+ brick->shadow_mem_limit,
+ atomic_read(&brick->sshadow_count),
+ atomic_read(&brick->hash_count),
+ atomic_read(&brick->sub_balance_count),
+ atomic_read(&brick->inner_balance_count),
+ atomic_read(&brick->outer_balance_count),
+ atomic_read(&brick->wb_balance_count),
+ atomic_read(&brick->inputs[TL_INPUT_LOG1]->pos_count),
+ atomic_read(&brick->inputs[TL_INPUT_LOG2]->pos_count),
+ atomic_read(&brick->inputs[TL_INPUT_LOG1]->log_obj_count),
+ atomic_read(&brick->inputs[TL_INPUT_LOG2]->log_obj_count),
+ atomic_read(&brick->any_fly_count),
+ atomic_read(&brick->log_fly_count),
+ atomic_read(&brick->inputs[TL_INPUT_LOG1]->logst.aio_flying),
+ atomic_read(&brick->inputs[TL_INPUT_LOG2]->logst.aio_flying),
+ atomic_read(&brick->q_phase[0].q_queued),
+ atomic_read(&brick->q_phase[0].q_flying),
+ brick->q_phase[0].pushback_count,
+ brick->q_phase[0].no_progress_count,
+ atomic_read(&brick->q_phase[1].q_queued),
+ atomic_read(&brick->q_phase[1].q_flying),
+ brick->q_phase[1].pushback_count,
+ brick->q_phase[1].no_progress_count,
+ atomic_read(&brick->q_phase[2].q_queued),
+ atomic_read(&brick->q_phase[2].q_flying),
+ brick->q_phase[2].pushback_count,
+ brick->q_phase[2].no_progress_count,
+ atomic_read(&brick->q_phase[3].q_queued),
+ atomic_read(&brick->q_phase[3].q_flying),
+ brick->q_phase[3].pushback_count,
+ brick->q_phase[3].no_progress_count);
+ return res;
+}
+
+static
+void trans_logger_reset_statistics(struct trans_logger_brick *brick)
+{
+ atomic_set(&brick->total_hash_insert_count, 0);
+ atomic_set(&brick->total_hash_find_count, 0);
+ atomic_set(&brick->total_hash_extend_count, 0);
+ atomic_set(&brick->total_replay_count, 0);
+ atomic_set(&brick->total_replay_conflict_count, 0);
+ atomic_set(&brick->total_cb_count, 0);
+ atomic_set(&brick->total_read_count, 0);
+ atomic_set(&brick->total_write_count, 0);
+ atomic_set(&brick->total_flush_count, 0);
+ atomic_set(&brick->total_writeback_count, 0);
+ atomic_set(&brick->total_writeback_cluster_count, 0);
+ atomic_set(&brick->total_shortcut_count, 0);
+ atomic_set(&brick->total_mshadow_count, 0);
+ atomic_set(&brick->total_sshadow_count, 0);
+ atomic_set(&brick->total_mshadow_buffered_count, 0);
+ atomic_set(&brick->total_sshadow_buffered_count, 0);
+ atomic_set(&brick->total_round_count, 0);
+ atomic_set(&brick->total_restart_count, 0);
+ atomic_set(&brick->total_delay_count, 0);
+}
+
+/*************** object * aspect constructors * destructors **************/
+
+static
+int trans_logger_aio_aspect_init_fn(struct generic_aspect *_ini)
+{
+ struct trans_logger_aio_aspect *ini = (void *)_ini;
+
+ ini->lh.lh_pos = &ini->object->io_pos;
+ INIT_LIST_HEAD(&ini->lh.lh_head);
+ INIT_LIST_HEAD(&ini->hash_head);
+ INIT_LIST_HEAD(&ini->pos_head);
+ INIT_LIST_HEAD(&ini->replay_head);
+ INIT_LIST_HEAD(&ini->collect_head);
+ INIT_LIST_HEAD(&ini->sub_list);
+ INIT_LIST_HEAD(&ini->sub_head);
+ return 0;
+}
+
+static
+void trans_logger_aio_aspect_exit_fn(struct generic_aspect *_ini)
+{
+ struct trans_logger_aio_aspect *ini = (void *)_ini;
+
+ CHECK_HEAD_EMPTY(&ini->lh.lh_head);
+ CHECK_HEAD_EMPTY(&ini->hash_head);
+ CHECK_HEAD_EMPTY(&ini->pos_head);
+ CHECK_HEAD_EMPTY(&ini->replay_head);
+ CHECK_HEAD_EMPTY(&ini->collect_head);
+ CHECK_HEAD_EMPTY(&ini->sub_list);
+ CHECK_HEAD_EMPTY(&ini->sub_head);
+ if (ini->log_input)
+ atomic_dec(&ini->log_input->log_obj_count);
+}
+
+XIO_MAKE_STATICS(trans_logger);
+
+/********************* brick constructors * destructors *******************/
+
+static
+void _free_pages(struct trans_logger_brick *brick)
+{
+ int i;
+
+ for (i = 0; i < NR_HASH_PAGES; i++) {
+ struct trans_logger_hash_anchor *sub_table = brick->hash_table[i];
+ int j;
+
+ if (!sub_table)
+ continue;
+ for (j = 0; j < HASH_PER_PAGE; j++) {
+ struct trans_logger_hash_anchor *start = &sub_table[j];
+
+ CHECK_HEAD_EMPTY(&start->hash_anchor);
+ }
+ brick_block_free(sub_table, PAGE_SIZE);
+ }
+ brick_block_free(brick->hash_table, PAGE_SIZE);
+}
+
+static
+int trans_logger_brick_construct(struct trans_logger_brick *brick)
+{
+ int i;
+
+ brick->hash_table = brick_block_alloc(0, PAGE_SIZE);
+ memset(brick->hash_table, 0, PAGE_SIZE);
+
+ for (i = 0; i < NR_HASH_PAGES; i++) {
+ struct trans_logger_hash_anchor *sub_table;
+ int j;
+
+ /* this should be usually optimized away as dead code */
+ if (unlikely(i >= MAX_HASH_PAGES)) {
+ XIO_ERR("sorry, subtable index %d is too large.\n", i);
+ _free_pages(brick);
+ return -EINVAL;
+ }
+
+ sub_table = brick_block_alloc(0, PAGE_SIZE);
+ brick->hash_table[i] = sub_table;
+
+ memset(sub_table, 0, PAGE_SIZE);
+ for (j = 0; j < HASH_PER_PAGE; j++) {
+ struct trans_logger_hash_anchor *start = &sub_table[j];
+
+ init_rwsem(&start->hash_mutex);
+ INIT_LIST_HEAD(&start->hash_anchor);
+ }
+ }
+
+ atomic_set(&brick->hash_count, 0);
+ spin_lock_init(&brick->replay_lock);
+ INIT_LIST_HEAD(&brick->replay_list);
+ INIT_LIST_HEAD(&brick->group_head);
+ init_waitqueue_head(&brick->worker_event);
+ init_waitqueue_head(&brick->caller_event);
+ qq_init(&brick->q_phase[0], brick);
+ qq_init(&brick->q_phase[1], brick);
+ qq_init(&brick->q_phase[2], brick);
+ qq_init(&brick->q_phase[3], brick);
+ brick->q_phase[0].q_insert_info = "q0_ins";
+ brick->q_phase[0].q_pushback_info = "q0_push";
+ brick->q_phase[0].q_fetch_info = "q0_fetch";
+ brick->q_phase[1].q_insert_info = "q1_ins";
+ brick->q_phase[1].q_pushback_info = "q1_push";
+ brick->q_phase[1].q_fetch_info = "q1_fetch";
+ brick->q_phase[2].q_insert_info = "q2_ins";
+ brick->q_phase[2].q_pushback_info = "q2_push";
+ brick->q_phase[2].q_fetch_info = "q2_fetch";
+ brick->q_phase[3].q_insert_info = "q3_ins";
+ brick->q_phase[3].q_pushback_info = "q3_push";
+ brick->q_phase[3].q_fetch_info = "q3_fetch";
+ brick->new_input_nr = TL_INPUT_LOG1;
+ brick->log_input_nr = TL_INPUT_LOG1;
+ brick->old_input_nr = TL_INPUT_LOG1;
+ add_to_group(&global_writeback, brick);
+ return 0;
+}
+
+static
+int trans_logger_brick_destruct(struct trans_logger_brick *brick)
+{
+ _free_pages(brick);
+ CHECK_HEAD_EMPTY(&brick->replay_list);
+ remove_from_group(&global_writeback, brick);
+ return 0;
+}
+
+static
+int trans_logger_output_construct(struct trans_logger_output *output)
+{
+ return 0;
+}
+
+static
+int trans_logger_input_construct(struct trans_logger_input *input)
+{
+ INIT_LIST_HEAD(&input->pos_list);
+ sema_init(&input->inf_mutex, 1);
+ return 0;
+}
+
+static
+int trans_logger_input_destruct(struct trans_logger_input *input)
+{
+ CHECK_HEAD_EMPTY(&input->pos_list);
+ return 0;
+}
+
+/************************ static structs ***********************/
+
+static struct trans_logger_brick_ops trans_logger_brick_ops = {
+ .brick_switch = trans_logger_switch,
+ .brick_statistics = trans_logger_statistics,
+ .reset_statistics = trans_logger_reset_statistics,
+};
+
+static struct trans_logger_output_ops trans_logger_output_ops = {
+ .xio_get_info = trans_logger_get_info,
+ .aio_get = trans_logger_io_get,
+ .aio_put = trans_logger_io_put,
+ .aio_io = trans_logger_io_io,
+};
+
+const struct trans_logger_input_type trans_logger_input_type = {
+ .type_name = "trans_logger_input",
+ .input_size = sizeof(struct trans_logger_input),
+ .input_construct = &trans_logger_input_construct,
+ .input_destruct = &trans_logger_input_destruct,
+};
+
+static const struct trans_logger_input_type *trans_logger_input_types[] = {
+ &trans_logger_input_type,
+ &trans_logger_input_type,
+ &trans_logger_input_type,
+ &trans_logger_input_type,
+ &trans_logger_input_type,
+ &trans_logger_input_type,
+};
+
+const struct trans_logger_output_type trans_logger_output_type = {
+ .type_name = "trans_logger_output",
+ .output_size = sizeof(struct trans_logger_output),
+ .master_ops = &trans_logger_output_ops,
+ .output_construct = &trans_logger_output_construct,
+};
+
+static const struct trans_logger_output_type *trans_logger_output_types[] = {
+ &trans_logger_output_type,
+};
+
+const struct trans_logger_brick_type trans_logger_brick_type = {
+ .type_name = "trans_logger_brick",
+ .brick_size = sizeof(struct trans_logger_brick),
+ .max_inputs = TL_INPUT_NR,
+ .max_outputs = 1,
+ .master_ops = &trans_logger_brick_ops,
+ .aspect_types = trans_logger_aspect_types,
+ .default_input_types = trans_logger_input_types,
+ .default_output_types = trans_logger_output_types,
+ .brick_construct = &trans_logger_brick_construct,
+ .brick_destruct = &trans_logger_brick_destruct,
+};
+
+/***************** module init stuff ************************/
+
+int __init init_xio_trans_logger(void)
+{
+ XIO_INF("init_trans_logger()\n");
+ return trans_logger_register_brick_type();
+}
+
+void exit_xio_trans_logger(void)
+{
+ XIO_INF("exit_trans_logger()\n");
+ trans_logger_unregister_brick_type();
+}
diff --git a/include/linux/xio/xio_trans_logger.h b/include/linux/xio/xio_trans_logger.h
new file mode 100644
index 0000000..f8fe4e5
--- /dev/null
+++ b/include/linux/xio/xio_trans_logger.h
@@ -0,0 +1,263 @@
+/*
+ * MARS Long Distance Replication Software
+ *
+ * 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.
+ */
+
+#ifndef XIO_TRANS_LOGGER_H
+#define XIO_TRANS_LOGGER_H
+
+#define REGION_SIZE_BITS (PAGE_SHIFT + 4)
+#define REGION_SIZE (1 << REGION_SIZE_BITS)
+#define LOGGER_QUEUES 4
+
+#include <linux/time.h>
+
+#include <linux/xio/xio.h>
+#include <linux/xio/lib_log.h>
+#include <linux/brick/lib_pairing_heap.h>
+#include <linux/brick/lib_queue.h>
+#include <linux/brick/lib_timing.h>
+
+/************************ global tuning ***********************/
+
+/* 0 = early completion of all writes
+ * 1 = early completion of non-sync
+ * 2 = late completion
+ */
+extern int trans_logger_completion_semantics;
+extern int trans_logger_do_crc;
+extern int trans_logger_mem_usage; /* in KB */
+extern int trans_logger_max_interleave;
+extern int trans_logger_resume;
+extern int trans_logger_replay_timeout; /* in s */
+extern atomic_t global_mshadow_count;
+extern atomic64_t global_mshadow_used;
+
+struct writeback_group {
+ rwlock_t lock;
+ struct trans_logger_brick *leader;
+ loff_t biggest;
+ struct list_head group_anchor;
+
+ /* tuning */
+ struct rate_limiter limiter;
+ int until_percent;
+};
+
+extern struct writeback_group global_writeback;
+
+/******************************************************************/
+
+_PAIRING_HEAP_TYPEDEF(logger, /*empty*/)
+
+struct logger_queue {
+ QUEUE_ANCHOR(logger, loff_t, logger);
+ struct trans_logger_brick *q_brick;
+ const char *q_insert_info;
+ const char *q_pushback_info;
+ const char *q_fetch_info;
+ struct banning q_banning;
+ int no_progress_count;
+ int pushback_count;
+};
+
+struct logger_head {
+ struct list_head lh_head;
+ loff_t *lh_pos;
+ struct pairing_heap_logger ph;
+};
+
+/******************************************************************/
+
+#define TL_INPUT_READ 0
+#define TL_INPUT_WRITEBACK 0
+#define TL_INPUT_LOG1 1
+#define TL_INPUT_LOG2 2
+#define TL_INPUT_NR 3
+
+struct writeback_info {
+ struct trans_logger_brick *w_brick;
+ struct logger_head w_lh;
+ loff_t w_pos;
+ int w_len;
+ int w_error;
+
+ struct list_head w_collect_list; /* list of collected orig requests */
+ struct list_head w_sub_read_list; /* for saving the old data before overwrite */
+ struct list_head w_sub_write_list; /* for overwriting */
+ atomic_t w_sub_read_count;
+ atomic_t w_sub_write_count;
+ atomic_t w_sub_log_count;
+ void (*read_endio)(struct generic_callback *cb);
+ void (*write_endio)(struct generic_callback *cb);
+};
+
+struct trans_logger_aio_aspect {
+ GENERIC_ASPECT(aio);
+ struct trans_logger_brick *my_brick;
+ struct trans_logger_input *my_input;
+ struct trans_logger_input *log_input;
+ struct logger_head lh;
+ struct list_head hash_head;
+ struct list_head pos_head;
+ struct list_head replay_head;
+ struct list_head collect_head;
+ struct pairing_heap_logger ph;
+ struct trans_logger_aio_aspect *shadow_aio;
+ struct trans_logger_aio_aspect *orig_aio_a;
+ void *shadow_data;
+ int orig_rw;
+ int wb_error;
+ bool do_dealloc;
+ bool do_buffered;
+ bool is_hashed;
+ bool is_stable;
+ bool is_dirty;
+ bool is_collected;
+ bool is_fired;
+ bool is_completed;
+ bool is_endio;
+ bool is_persistent;
+ bool is_emergency;
+ struct timespec stamp;
+ loff_t log_pos;
+ struct generic_callback cb;
+ struct writeback_info *wb;
+ struct list_head sub_list;
+ struct list_head sub_head;
+ int total_sub_count;
+ int alloc_len;
+ atomic_t current_sub_count;
+};
+
+struct trans_logger_hash_anchor;
+
+struct trans_logger_brick {
+ XIO_BRICK(trans_logger);
+ /* parameters */
+ struct rate_limiter *replay_limiter;
+
+ int shadow_mem_limit; /* max # master shadows */
+ bool replay_mode; /* mode of operation */
+ bool continuous_replay_mode; /* mode of operation */
+ bool log_reads; /* additionally log pre-images */
+ bool cease_logging; /* direct IO without logging (only in case of EMERGENCY) */
+ loff_t replay_start_pos; /* where to start replay */
+ loff_t replay_end_pos; /* end of replay */
+ int new_input_nr; /* whereto we should switchover ASAP */
+ int replay_tolerance; /* how many bytes to ignore at truncated logfiles */
+ /* readonly from outside */
+ loff_t replay_current_pos; /* end of replay */
+ int log_input_nr; /* where we are currently logging to */
+ int old_input_nr; /* where old IO requests may be on the fly */
+ int replay_code; /* replay errors (if any) */
+ bool stopped_logging; /* direct IO without logging (only in case of EMERGENCY) */
+ /* private */
+ int disk_io_error; /* replay errors from callbacks */
+ struct trans_logger_hash_anchor **hash_table;
+ struct list_head group_head;
+ loff_t old_margin;
+ spinlock_t replay_lock;
+ struct list_head replay_list;
+ struct task_struct *thread;
+
+ wait_queue_head_t worker_event;
+ wait_queue_head_t caller_event;
+ /* statistics */
+ atomic64_t shadow_mem_used;
+ atomic_t replay_count;
+ atomic_t any_fly_count;
+ atomic_t log_fly_count;
+ atomic_t hash_count;
+ atomic_t mshadow_count;
+ atomic_t sshadow_count;
+ atomic_t outer_balance_count;
+ atomic_t inner_balance_count;
+ atomic_t sub_balance_count;
+ atomic_t wb_balance_count;
+ atomic_t total_hash_insert_count;
+ atomic_t total_hash_find_count;
+ atomic_t total_hash_extend_count;
+ atomic_t total_replay_count;
+ atomic_t total_replay_conflict_count;
+ atomic_t total_cb_count;
+ atomic_t total_read_count;
+ atomic_t total_write_count;
+ atomic_t total_flush_count;
+ atomic_t total_writeback_count;
+ atomic_t total_writeback_cluster_count;
+ atomic_t total_shortcut_count;
+ atomic_t total_mshadow_count;
+ atomic_t total_sshadow_count;
+ atomic_t total_mshadow_buffered_count;
+ atomic_t total_sshadow_buffered_count;
+ atomic_t total_round_count;
+ atomic_t total_restart_count;
+ atomic_t total_delay_count;
+
+ /* queues */
+ struct logger_queue q_phase[LOGGER_QUEUES];
+ bool delay_callers;
+};
+
+struct trans_logger_output {
+ XIO_OUTPUT(trans_logger);
+};
+
+#define MAX_HOST_LEN 32
+
+struct trans_logger_info {
+ /* to be maintained / initialized from outside */
+ void (*inf_callback)(struct trans_logger_info *inf);
+ void *inf_private;
+ char inf_host[MAX_HOST_LEN];
+
+ int inf_sequence; /* logfile sequence number */
+
+ /* maintained by trans_logger */
+ loff_t inf_min_pos; /* current replay position (both in replay mode and in logging mode) */
+ loff_t inf_max_pos; /* dito, indicating the "dirty" area which could be potentially "inconsistent" */
+ loff_t inf_log_pos; /* position of transaction logging (may be ahead of replay position) */
+ struct timespec inf_min_pos_stamp; /* when the data has been _successfully_ overwritten */
+/* when the data has _started_ overwrite (maybe "trashed" in case of errors / aborts) */
+ struct timespec inf_max_pos_stamp;
+
+ struct timespec inf_log_pos_stamp; /* stamp from transaction log */
+ bool inf_is_replaying;
+ bool inf_is_logging;
+};
+
+struct trans_logger_input {
+ XIO_INPUT(trans_logger);
+ /* parameters */
+ /* informational */
+ struct trans_logger_info inf;
+
+ /* readonly from outside */
+ atomic_t log_obj_count;
+ atomic_t pos_count;
+ bool is_operating;
+ long long last_jiffies;
+
+ /* private */
+ struct log_status logst;
+ struct list_head pos_list;
+ long long inf_last_jiffies;
+ struct semaphore inf_mutex;
+};
+
+XIO_TYPES(trans_logger);
+
+#endif
--
2.6.4

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