Add RAID statistics counters to /proc/mdstat Index: linux-2.6.9/include/linux/raid/raid5.h =================================================================== --- linux-2.6.9.orig/include/linux/raid/raid5.h 2004-10-19 01:54:55.000000000 +0400 +++ linux-2.6.9/include/linux/raid/raid5.h 2006-05-17 14:10:53.000000000 +0400 @@ -222,6 +222,22 @@ struct raid5_private_data { int inactive_blocked; /* release of inactive stripes blocked, * waiting for 25% to be free */ + /* + * Stats + */ + atomic_t reads_in; + atomic_t writes_in; + atomic_t reads_out; + atomic_t writes_out; + atomic_t handled_in_raid5d; + atomic_t out_of_stripes; + atomic_t reads_for_rmw; + atomic_t reads_for_rcw; + atomic_t handle_called; + atomic_t delayed; + atomic_t in_reqs_in_queue; + atomic_t out_reqs_in_queue; + spinlock_t device_lock; struct disk_info disks[0]; }; Index: linux-2.6.9/drivers/md/raid5.c =================================================================== --- linux-2.6.9.orig/drivers/md/raid5.c 2006-03-10 18:20:48.000000000 +0300 +++ linux-2.6.9/drivers/md/raid5.c 2006-05-17 14:10:53.000000000 +0400 @@ -77,9 +77,10 @@ static inline void __release_stripe(raid if (atomic_read(&conf->active_stripes)==0) BUG(); if (test_bit(STRIPE_HANDLE, &sh->state)) { - if (test_bit(STRIPE_DELAYED, &sh->state)) + if (test_bit(STRIPE_DELAYED, &sh->state)) { list_add_tail(&sh->lru, &conf->delayed_list); - else + atomic_inc(&conf->delayed); + } else list_add_tail(&sh->lru, &conf->handle_list); md_wakeup_thread(conf->mddev->thread); } else { @@ -250,6 +251,7 @@ static struct stripe_head *get_active_st if (noblock && sh == NULL) break; if (!sh) { + atomic_inc(&conf->out_of_stripes); conf->inactive_blocked = 1; wait_event_lock_irq(conf->wait_for_stripe, !list_empty(&conf->inactive_list) && @@ -271,6 +273,8 @@ static struct stripe_head *get_active_st if (list_empty(&sh->lru)) BUG(); list_del_init(&sh->lru); + if (test_bit(STRIPE_DELAYED, &sh->state)) + atomic_dec(&conf->delayed); } } } while (sh == NULL); @@ -349,6 +353,8 @@ static int raid5_end_read_request (struc if (bi->bi_size) return 1; + atomic_dec(&conf->out_reqs_in_queue); + for (i=0 ; idev[i].req) break; @@ -422,6 +428,8 @@ static int raid5_end_write_request (stru if (bi->bi_size) return 1; + atomic_dec(&conf->out_reqs_in_queue); + for (i=0 ; idev[i].req) break; @@ -882,6 +890,7 @@ static void handle_stripe(struct stripe_ spin_lock(&sh->lock); clear_bit(STRIPE_HANDLE, &sh->state); clear_bit(STRIPE_DELAYED, &sh->state); + atomic_inc(&conf->handle_called); syncing = test_bit(STRIPE_SYNCING, &sh->state); /* Now to look around and see what can be done */ @@ -1127,6 +1136,7 @@ static void handle_stripe(struct stripe_ set_bit(R5_LOCKED, &dev->flags); set_bit(R5_Wantread, &dev->flags); locked++; + atomic_inc(&conf->reads_for_rmw); } else { set_bit(STRIPE_DELAYED, &sh->state); set_bit(STRIPE_HANDLE, &sh->state); @@ -1146,6 +1156,7 @@ static void handle_stripe(struct stripe_ set_bit(R5_LOCKED, &dev->flags); set_bit(R5_Wantread, &dev->flags); locked++; + atomic_inc(&conf->reads_for_rcw); } else { set_bit(STRIPE_DELAYED, &sh->state); set_bit(STRIPE_HANDLE, &sh->state); @@ -1228,6 +1239,7 @@ static void handle_stripe(struct stripe_ bi->bi_next = NULL; bi->bi_size = 0; bi->bi_end_io(bi, bytes, 0); + atomic_dec(&conf->in_reqs_in_queue); } for (i=disks; i-- ;) { int rw; @@ -1243,10 +1255,13 @@ static void handle_stripe(struct stripe_ bi = &sh->dev[i].req; bi->bi_rw = rw; - if (rw) + if (rw) { + atomic_inc(&conf->writes_out); bi->bi_end_io = raid5_end_write_request; - else + } else { + atomic_inc(&conf->reads_out); bi->bi_end_io = raid5_end_read_request; + } spin_lock_irq(&conf->device_lock); rdev = conf->disks[i].rdev; @@ -1274,6 +1289,7 @@ static void handle_stripe(struct stripe_ bi->bi_io_vec[0].bv_offset = 0; bi->bi_size = STRIPE_SIZE; bi->bi_next = NULL; + atomic_inc(&conf->out_reqs_in_queue); generic_make_request(bi); } else { PRINTK("skip op %ld on disc %d for sector %llu\n", @@ -1296,6 +1312,7 @@ static inline void raid5_activate_delaye if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) atomic_inc(&conf->preread_active_stripes); list_add_tail(&sh->lru, &conf->handle_list); + atomic_dec(&conf->delayed); } } } @@ -1395,12 +1412,16 @@ static int make_request (request_queue_t sector_t logical_sector, last_sector; struct stripe_head *sh; + atomic_inc(&conf->in_reqs_in_queue); + if (bio_data_dir(bi)==WRITE) { disk_stat_inc(mddev->gendisk, writes); disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bi)); + atomic_inc(&conf->writes_in); } else { disk_stat_inc(mddev->gendisk, reads); disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bi)); + atomic_inc(&conf->reads_in); } logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); @@ -1439,6 +1460,7 @@ static int make_request (request_queue_t if ( bio_data_dir(bi) == WRITE ) md_write_end(mddev); + atomic_dec(&conf->in_reqs_in_queue); bi->bi_size = 0; bi->bi_end_io(bi, bytes, 0); } @@ -1535,6 +1557,7 @@ static void raid5d (mddev_t *mddev) spin_unlock_irq(&conf->device_lock); handled++; + atomic_inc(&conf->handled_in_raid5d); handle_stripe(sh); release_stripe(sh); @@ -1767,6 +1790,21 @@ static void status (struct seq_file *seq conf->disks[i].rdev && conf->disks[i].rdev->in_sync ? "U" : "_"); seq_printf (seq, "]"); + seq_printf (seq, "\n\t\tin: %u reads, %u writes; out: %u reads, %u writes", + atomic_read(&conf->reads_in), atomic_read(&conf->writes_in), + atomic_read(&conf->reads_out), atomic_read(&conf->writes_out)); + seq_printf (seq, "\n\t\t%u in raid5d, %u out of stripes, %u handle called", + atomic_read(&conf->handled_in_raid5d), + atomic_read(&conf->out_of_stripes), + atomic_read(&conf->handle_called)); + seq_printf (seq, "\n\t\treads: %u for rmw, %u for rcw", + atomic_read(&conf->reads_for_rmw), + atomic_read(&conf->reads_for_rcw)); + seq_printf (seq, "\n\t\t%u delayed, %u active, queues: %u in, %u out\n", + atomic_read(&conf->delayed), + atomic_read(&conf->active_stripes), + atomic_read(&conf->in_reqs_in_queue), + atomic_read(&conf->out_reqs_in_queue)); #if RAID5_DEBUG #define D(x) \ seq_printf (seq, "<"#x":%d>", atomic_read(&conf->x))