[PATCH v2 7/8] zbd: initialize valid data bytes accounting at file set up

[Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>]

The valid data bytes accounting field is initialized at file reset,
after each job started. Each job locks zones to check write pointer
positions of its write target zones. This can cause zone lock contention
with write by other jobs.

To avoid the zone lock contention, move the initialization from file
reset to file set up before job start. It allows to access the write
pointers and the accounting field without locks. Remove the lock and
unlock codes which are no longer required. Ensure the locks are not
required by checking run-state in the struct thread_data.

Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
---
 zbd.c | 93 ++++++++++++++++++++++++++++-------------------------------
 1 file changed, 44 insertions(+), 49 deletions(-)

diff --git a/zbd.c b/zbd.c
index ca6816b9..a464d6df 100644
--- a/zbd.c
+++ b/zbd.c
@@ -1074,6 +1074,44 @@ void zbd_recalc_options_with_zone_granularity(struct thread_data *td)
 	}
 }
 
+static uint64_t zbd_set_vdb(struct thread_data *td, const struct fio_file *f)
+{
+	struct fio_zone_info *zb, *ze, *z;
+	uint64_t wp_vdb = 0;
+	struct zoned_block_device_info *zbdi = f->zbd_info;
+
+	assert(td->runstate < TD_RUNNING);
+	assert(zbdi);
+
+	if (!accounting_vdb(td, f))
+		return 0;
+
+	if (zbdi->wp_write_min_zone != zbdi->wp_write_max_zone) {
+		if (zbdi->wp_write_min_zone != f->min_zone ||
+		    zbdi->wp_write_max_zone != f->max_zone) {
+			td_verror(td, EINVAL,
+				  "multi-jobs with different write ranges are "
+				  "not supported with zone_reset_threshold");
+			log_err("multi-jobs with different write ranges are "
+				"not supported with zone_reset_threshold\n");
+		}
+		return 0;
+	}
+
+	zbdi->wp_write_min_zone = f->min_zone;
+	zbdi->wp_write_max_zone = f->max_zone;
+
+	zb = zbd_get_zone(f, f->min_zone);
+	ze = zbd_get_zone(f, f->max_zone);
+	for (z = zb; z < ze; z++)
+		if (z->has_wp)
+			wp_vdb += z->wp - z->start;
+
+	zbdi->wp_valid_data_bytes = wp_vdb;
+
+	return wp_vdb;
+}
+
 int zbd_setup_files(struct thread_data *td)
 {
 	struct fio_file *f;
@@ -1099,6 +1137,7 @@ int zbd_setup_files(struct thread_data *td)
 		struct zoned_block_device_info *zbd = f->zbd_info;
 		struct fio_zone_info *z;
 		int zi;
+		uint64_t vdb;
 
 		assert(zbd);
 
@@ -1106,6 +1145,11 @@ int zbd_setup_files(struct thread_data *td)
 		f->max_zone =
 			zbd_offset_to_zone_idx(f, f->file_offset + f->io_size);
 
+		vdb = zbd_set_vdb(td, f);
+
+		dprint(FD_ZBD, "%s(%s): valid data bytes = %" PRIu64 "\n",
+		       __func__, f->file_name, vdb);
+
 		/*
 		 * When all zones in the I/O range are conventional, io_size
 		 * can be smaller than zone size, making min_zone the same
@@ -1197,54 +1241,9 @@ static bool zbd_dec_and_reset_write_cnt(const struct thread_data *td,
 	return write_cnt == 0;
 }
 
-static uint64_t zbd_set_vdb(struct thread_data *td, const struct fio_file *f)
-{
-	struct fio_zone_info *zb, *ze, *z;
-	uint64_t wp_vdb = 0;
-	struct zoned_block_device_info *zbdi = f->zbd_info;
-
-	if (!accounting_vdb(td, f))
-		return 0;
-
-	if (zbdi->wp_write_min_zone != zbdi->wp_write_max_zone) {
-		if (zbdi->wp_write_min_zone != f->min_zone ||
-		    zbdi->wp_write_max_zone != f->max_zone) {
-			td_verror(td, EINVAL,
-				  "multi-jobs with different write ranges are "
-				  "not supported with zone_reset_threshold");
-			log_err("multi-jobs with different write ranges are "
-				"not supported with zone_reset_threshold\n");
-		}
-		return 0;
-	}
-
-	zbdi->wp_write_min_zone = f->min_zone;
-	zbdi->wp_write_max_zone = f->max_zone;
-
-	zb = zbd_get_zone(f, f->min_zone);
-	ze = zbd_get_zone(f, f->max_zone);
-	for (z = zb; z < ze; z++) {
-		if (z->has_wp) {
-			zone_lock(td, f, z);
-			wp_vdb += z->wp - z->start;
-		}
-	}
-
-	pthread_mutex_lock(&zbdi->mutex);
-	zbdi->wp_valid_data_bytes = wp_vdb;
-	pthread_mutex_unlock(&zbdi->mutex);
-
-	for (z = zb; z < ze; z++)
-		if (z->has_wp)
-			zone_unlock(z);
-
-	return wp_vdb;
-}
-
 void zbd_file_reset(struct thread_data *td, struct fio_file *f)
 {
 	struct fio_zone_info *zb, *ze;
-	uint64_t vdb;
 	bool verify_data_left = false;
 
 	if (!f->zbd_info || !td_write(td))
@@ -1252,10 +1251,6 @@ void zbd_file_reset(struct thread_data *td, struct fio_file *f)
 
 	zb = zbd_get_zone(f, f->min_zone);
 	ze = zbd_get_zone(f, f->max_zone);
-	vdb = zbd_set_vdb(td, f);
-
-	dprint(FD_ZBD, "%s(%s): valid data bytes = %" PRIu64 "\n",
-	       __func__, f->file_name, vdb);
 
 	/*
 	 * If data verification is enabled reset the affected zones before
-- 
2.38.1