[PATCH] Split the io_u io handling out of fio.c
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/io_u.c b/io_u.c
new file mode 100644
index 0000000..baf5d47
--- /dev/null
+++ b/io_u.c
@@ -0,0 +1,331 @@
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <signal.h>
+#include <time.h>
+#include <assert.h>
+
+#include "fio.h"
+#include "os.h"
+
+/*
+ * The ->file_map[] contains a map of blocks we have or have not done io
+ * to yet. Used to make sure we cover the entire range in a fair fashion.
+ */
+static int random_map_free(struct thread_data *td, struct fio_file *f,
+ unsigned long long block)
+{
+ unsigned int idx = RAND_MAP_IDX(td, f, block);
+ unsigned int bit = RAND_MAP_BIT(td, f, block);
+
+ return (f->file_map[idx] & (1UL << bit)) == 0;
+}
+
+/*
+ * Return the next free block in the map.
+ */
+static int get_next_free_block(struct thread_data *td, struct fio_file *f,
+ unsigned long long *b)
+{
+ int i;
+
+ *b = 0;
+ i = 0;
+ while ((*b) * td->min_bs < f->file_size) {
+ if (f->file_map[i] != -1UL) {
+ *b += ffz(f->file_map[i]);
+ return 0;
+ }
+
+ *b += BLOCKS_PER_MAP;
+ i++;
+ }
+
+ return 1;
+}
+
+/*
+ * For random io, generate a random new block and see if it's used. Repeat
+ * until we find a free one. For sequential io, just return the end of
+ * the last io issued.
+ */
+static int get_next_offset(struct thread_data *td, struct fio_file *f,
+ unsigned long long *offset)
+{
+ unsigned long long b, rb;
+ long r;
+
+ if (!td->sequential) {
+ unsigned long long max_blocks = td->io_size / td->min_bs;
+ int loops = 50;
+
+ do {
+ r = os_random_long(&td->random_state);
+ b = ((max_blocks - 1) * r / (unsigned long long) (RAND_MAX+1.0));
+ rb = b + (f->file_offset / td->min_bs);
+ loops--;
+ } while (!random_map_free(td, f, rb) && loops);
+
+ if (!loops) {
+ if (get_next_free_block(td, f, &b))
+ return 1;
+ }
+ } else
+ b = f->last_pos / td->min_bs;
+
+ *offset = (b * td->min_bs) + f->file_offset;
+ if (*offset > f->file_size)
+ return 1;
+
+ return 0;
+}
+
+static unsigned int get_next_buflen(struct thread_data *td)
+{
+ unsigned int buflen;
+ long r;
+
+ if (td->min_bs == td->max_bs)
+ buflen = td->min_bs;
+ else {
+ r = os_random_long(&td->bsrange_state);
+ buflen = (1 + (double) (td->max_bs - 1) * r / (RAND_MAX + 1.0));
+ buflen = (buflen + td->min_bs - 1) & ~(td->min_bs - 1);
+ }
+
+ if (buflen > td->io_size - td->this_io_bytes[td->ddir]) {
+ /*
+ * if using direct/raw io, we may not be able to
+ * shrink the size. so just fail it.
+ */
+ if (td->io_ops->flags & FIO_RAWIO)
+ return 0;
+
+ buflen = td->io_size - td->this_io_bytes[td->ddir];
+ }
+
+ return buflen;
+}
+
+/*
+ * Return the data direction for the next io_u. If the job is a
+ * mixed read/write workload, check the rwmix cycle and switch if
+ * necessary.
+ */
+static int get_rw_ddir(struct thread_data *td)
+{
+ if (td_rw(td)) {
+ struct timeval now;
+ unsigned long elapsed;
+
+ gettimeofday(&now, NULL);
+ elapsed = mtime_since_now(&td->rwmix_switch);
+
+ /*
+ * Check if it's time to seed a new data direction.
+ */
+ if (elapsed >= td->rwmixcycle) {
+ unsigned int v;
+ long r;
+
+ r = os_random_long(&td->rwmix_state);
+ v = 1 + (int) (100.0 * (r / (RAND_MAX + 1.0)));
+ if (v < td->rwmixread)
+ td->rwmix_ddir = DDIR_READ;
+ else
+ td->rwmix_ddir = DDIR_WRITE;
+ memcpy(&td->rwmix_switch, &now, sizeof(now));
+ }
+ return td->rwmix_ddir;
+ } else if (td_read(td))
+ return DDIR_READ;
+ else
+ return DDIR_WRITE;
+}
+
+/*
+ * Mark a given offset as used in the map.
+ */
+static void mark_random_map(struct thread_data *td, struct fio_file *f,
+ struct io_u *io_u)
+{
+ unsigned long long block = io_u->offset / (unsigned long long) td->min_bs;
+ unsigned int blocks = 0;
+
+ while (blocks < (io_u->buflen / td->min_bs)) {
+ unsigned int idx, bit;
+
+ if (!random_map_free(td, f, block))
+ break;
+
+ idx = RAND_MAP_IDX(td, f, block);
+ bit = RAND_MAP_BIT(td, f, block);
+
+ assert(idx < f->num_maps);
+
+ f->file_map[idx] |= (1UL << bit);
+ block++;
+ blocks++;
+ }
+
+ if ((blocks * td->min_bs) < io_u->buflen)
+ io_u->buflen = blocks * td->min_bs;
+}
+
+void put_io_u(struct thread_data *td, struct io_u *io_u)
+{
+ io_u->file = NULL;
+ list_del(&io_u->list);
+ list_add(&io_u->list, &td->io_u_freelist);
+ td->cur_depth--;
+}
+
+static int fill_io_u(struct thread_data *td, struct fio_file *f,
+ struct io_u *io_u)
+{
+ /*
+ * If using an iolog, grab next piece if any available.
+ */
+ if (td->read_iolog)
+ return read_iolog_get(td, io_u);
+
+ /*
+ * No log, let the seq/rand engine retrieve the next position.
+ */
+ if (!get_next_offset(td, f, &io_u->offset)) {
+ io_u->buflen = get_next_buflen(td);
+
+ if (io_u->buflen) {
+ io_u->ddir = get_rw_ddir(td);
+
+ /*
+ * If using a write iolog, store this entry.
+ */
+ if (td->write_iolog)
+ write_iolog_put(td, io_u);
+
+ io_u->file = f;
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+struct io_u *__get_io_u(struct thread_data *td)
+{
+ struct io_u *io_u = NULL;
+
+ if (!queue_full(td)) {
+ io_u = list_entry(td->io_u_freelist.next, struct io_u, list);
+
+ io_u->error = 0;
+ io_u->resid = 0;
+ list_del(&io_u->list);
+ list_add(&io_u->list, &td->io_u_busylist);
+ td->cur_depth++;
+ }
+
+ return io_u;
+}
+
+/*
+ * Return an io_u to be processed. Gets a buflen and offset, sets direction,
+ * etc. The returned io_u is fully ready to be prepped and submitted.
+ */
+struct io_u *get_io_u(struct thread_data *td, struct fio_file *f)
+{
+ struct io_u *io_u;
+
+ io_u = __get_io_u(td);
+ if (!io_u)
+ return NULL;
+
+ if (td->zone_bytes >= td->zone_size) {
+ td->zone_bytes = 0;
+ f->last_pos += td->zone_skip;
+ }
+
+ if (fill_io_u(td, f, io_u)) {
+ put_io_u(td, io_u);
+ return NULL;
+ }
+
+ if (io_u->buflen + io_u->offset > f->file_size) {
+ if (td->io_ops->flags & FIO_RAWIO) {
+ put_io_u(td, io_u);
+ return NULL;
+ }
+
+ io_u->buflen = f->file_size - io_u->offset;
+ }
+
+ if (!io_u->buflen) {
+ put_io_u(td, io_u);
+ return NULL;
+ }
+
+ if (!td->read_iolog && !td->sequential)
+ mark_random_map(td, f, io_u);
+
+ f->last_pos += io_u->buflen;
+
+ if (td->verify != VERIFY_NONE)
+ populate_verify_io_u(td, io_u);
+
+ if (td_io_prep(td, io_u)) {
+ put_io_u(td, io_u);
+ return NULL;
+ }
+
+ gettimeofday(&io_u->start_time, NULL);
+ return io_u;
+}
+
+void io_completed(struct thread_data *td, struct io_u *io_u,
+ struct io_completion_data *icd)
+{
+ struct timeval e;
+ unsigned long msec;
+
+ gettimeofday(&e, NULL);
+
+ if (!io_u->error) {
+ unsigned int bytes = io_u->buflen - io_u->resid;
+ const int idx = io_u->ddir;
+
+ td->io_blocks[idx]++;
+ td->io_bytes[idx] += bytes;
+ td->zone_bytes += bytes;
+ td->this_io_bytes[idx] += bytes;
+
+ msec = mtime_since(&io_u->issue_time, &e);
+
+ add_clat_sample(td, idx, msec);
+ add_bw_sample(td, idx);
+
+ if ((td_rw(td) || td_write(td)) && idx == DDIR_WRITE)
+ log_io_piece(td, io_u);
+
+ icd->bytes_done[idx] += bytes;
+ } else
+ icd->error = io_u->error;
+}
+
+void ios_completed(struct thread_data *td, struct io_completion_data *icd)
+{
+ struct io_u *io_u;
+ int i;
+
+ icd->error = 0;
+ icd->bytes_done[0] = icd->bytes_done[1] = 0;
+
+ for (i = 0; i < icd->nr; i++) {
+ io_u = td->io_ops->event(td, i);
+
+ io_completed(td, io_u, icd);
+ put_io_u(td, io_u);
+ }
+}
+
+