block: return just one value from part_in_flight

The previous patches deleted all the code that needed the second value
returned from part_in_flight - now the kernel only uses the first value.

Consequently, part_in_flight (and blk_mq_in_flight) may be changed so that
it only returns one value.

This patch just refactors the code, there's no functional change.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

5 files changed, 22 insertions, 36 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index b645275dfe5f..9690f4f8de7e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -100,25 +100,23 @@ static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
         struct mq_inflight *mi = priv;
 
         /*
-         * index[0] counts the specific partition that was asked for. index[1]
-         * counts the ones that are active on the whole device, so increment
-         * that if mi->part is indeed a partition, and not a whole device.
+         * index[0] counts the specific partition that was asked for.
          */
         if (rq->part == mi->part)
                 mi->inflight[0]++;
-        if (mi->part->partno)
-                mi->inflight[1]++;
 
         return true;
 }
 
-void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
-                      unsigned int inflight[2])
+unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
 {
+        unsigned inflight[2];
         struct mq_inflight mi = { .part = part, .inflight = inflight, };
 
         inflight[0] = inflight[1] = 0;
         blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi);
+
+        return inflight[0];
 }
 
 static bool blk_mq_check_inflight_rw(struct blk_mq_hw_ctx *hctx,
diff --git a/block/blk-mq.h b/block/blk-mq.h
index a664ea44ffd4..0c9c9ea2fefe 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -187,8 +187,7 @@ static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
         return hctx->nr_ctx && hctx->tags;
 }
 
-void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
-                      unsigned int inflight[2]);
+unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
 void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
                          unsigned int inflight[2]);
 
diff --git a/block/genhd.c b/block/genhd.c
index 9827a2c05db7..1dd8fd6613b8 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -65,34 +65,24 @@ void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw)
                 part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]);
 }
 
-void part_in_flight(struct request_queue *q, struct hd_struct *part,
-                    unsigned int inflight[2])
+unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part)
 {
         int cpu;
+        unsigned int inflight;
 
         if (queue_is_mq(q)) {
-                blk_mq_in_flight(q, part, inflight);
-                return;
+                return blk_mq_in_flight(q, part);
         }
 
-        inflight[0] = 0;
+        inflight = 0;
         for_each_possible_cpu(cpu) {
-                inflight[0] += part_stat_local_read_cpu(part, in_flight[0], cpu) +
-                               part_stat_local_read_cpu(part, in_flight[1], cpu);
+                inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) +
+                            part_stat_local_read_cpu(part, in_flight[1], cpu);
         }
-        if ((int)inflight[0] < 0)
-                inflight[0] = 0;
+        if ((int)inflight < 0)
+                inflight = 0;
 
-        if (part->partno) {
-                part = &part_to_disk(part)->part0;
-                inflight[1] = 0;
-                for_each_possible_cpu(cpu) {
-                        inflight[1] += part_stat_local_read_cpu(part, in_flight[0], cpu) +
-                                       part_stat_local_read_cpu(part, in_flight[1], cpu);
-                }
-                if ((int)inflight[1] < 0)
-                        inflight[1] = 0;
-        }
+        return inflight;
 }
 
 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
@@ -1348,7 +1338,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
         struct disk_part_iter piter;
         struct hd_struct *hd;
         char buf[BDEVNAME_SIZE];
-        unsigned int inflight[2];
+        unsigned int inflight;
 
         /*
         if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
@@ -1360,7 +1350,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
 
         disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
         while ((hd = disk_part_iter_next(&piter))) {
-                part_in_flight(gp->queue, hd, inflight);
+                inflight = part_in_flight(gp->queue, hd);
                 seq_printf(seqf, "%4d %7d %s "
                            "%lu %lu %lu %u "
                            "%lu %lu %lu %u "
@@ -1376,7 +1366,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
                            part_stat_read(hd, merges[STAT_WRITE]),
                            part_stat_read(hd, sectors[STAT_WRITE]),
                            (unsigned int)part_stat_read_msecs(hd, STAT_WRITE),
-                           inflight[0],
+                           inflight,
                            jiffies_to_msecs(part_stat_read(hd, io_ticks)),
                            jiffies_to_msecs(part_stat_read(hd, time_in_queue)),
                            part_stat_read(hd, ios[STAT_DISCARD]),
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 42d6138ac876..8e596a8dff32 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -120,9 +120,9 @@ ssize_t part_stat_show(struct device *dev,
 {
         struct hd_struct *p = dev_to_part(dev);
         struct request_queue *q = part_to_disk(p)->queue;
-        unsigned int inflight[2];
+        unsigned int inflight;
 
-        part_in_flight(q, p, inflight);
+        inflight = part_in_flight(q, p);
         return sprintf(buf,
                 "%8lu %8lu %8llu %8u "
                 "%8lu %8lu %8llu %8u "
@@ -137,7 +137,7 @@ ssize_t part_stat_show(struct device *dev,
                 part_stat_read(p, merges[STAT_WRITE]),
                 (unsigned long long)part_stat_read(p, sectors[STAT_WRITE]),
                 (unsigned int)part_stat_read_msecs(p, STAT_WRITE),
-                inflight[0],
+                inflight,
                 jiffies_to_msecs(part_stat_read(p, io_ticks)),
                 jiffies_to_msecs(part_stat_read(p, time_in_queue)),
                 part_stat_read(p, ios[STAT_DISCARD]),
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 636b4f687e35..06c0fd594097 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -391,8 +391,7 @@ static inline void free_part_stats(struct hd_struct *part)
 #define part_stat_local_read_cpu(gendiskp, field, cpu)                  \
         local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
 
-void part_in_flight(struct request_queue *q, struct hd_struct *part,
-                    unsigned int inflight[2]);
+unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part);
 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
                        unsigned int inflight[2]);
 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,