diff options
| -rw-r--r-- | drivers/md/md.c | 45 |
1 files changed, 28 insertions, 17 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 612343fdde94..5eb01a4d27ba 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5705,37 +5705,38 @@ static void status_unused(struct seq_file *seq) static void status_resync(struct seq_file *seq, mddev_t * mddev) { - sector_t max_blocks, resync, res; - unsigned long dt, db, rt; + sector_t max_sectors, resync, res; + unsigned long dt, db; + sector_t rt; int scale; unsigned int per_milli; - resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2; + resync = mddev->curr_resync - atomic_read(&mddev->recovery_active); if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) - max_blocks = mddev->resync_max_sectors >> 1; + max_sectors = mddev->resync_max_sectors; else - max_blocks = mddev->dev_sectors / 2; + max_sectors = mddev->dev_sectors; /* * Should not happen. */ - if (!max_blocks) { + if (!max_sectors) { MD_BUG(); return; } /* Pick 'scale' such that (resync>>scale)*1000 will fit - * in a sector_t, and (max_blocks>>scale) will fit in a + * in a sector_t, and (max_sectors>>scale) will fit in a * u32, as those are the requirements for sector_div. * Thus 'scale' must be at least 10 */ scale = 10; if (sizeof(sector_t) > sizeof(unsigned long)) { - while ( max_blocks/2 > (1ULL<<(scale+32))) + while ( max_sectors/2 > (1ULL<<(scale+32))) scale++; } res = (resync>>scale)*1000; - sector_div(res, (u32)((max_blocks>>scale)+1)); + sector_div(res, (u32)((max_sectors>>scale)+1)); per_milli = res; { @@ -5756,25 +5757,35 @@ static void status_resync(struct seq_file *seq, mddev_t * mddev) (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ? "resync" : "recovery"))), per_milli/10, per_milli % 10, - (unsigned long long) resync, - (unsigned long long) max_blocks); + (unsigned long long) resync/2, + (unsigned long long) max_sectors/2); /* - * We do not want to overflow, so the order of operands and - * the * 100 / 100 trick are important. We do a +1 to be - * safe against division by zero. We only estimate anyway. - * * dt: time from mark until now * db: blocks written from mark until now * rt: remaining time + * + * rt is a sector_t, so could be 32bit or 64bit. + * So we divide before multiply in case it is 32bit and close + * to the limit. + * We scale the divisor (db) by 32 to avoid loosing precision + * near the end of resync when the number of remaining sectors + * is close to 'db'. + * We then divide rt by 32 after multiplying by db to compensate. + * The '+1' avoids division by zero if db is very small. */ dt = ((jiffies - mddev->resync_mark) / HZ); if (!dt) dt++; db = (mddev->curr_mark_cnt - atomic_read(&mddev->recovery_active)) - mddev->resync_mark_cnt; - rt = (dt * ((unsigned long)(max_blocks-resync) / (db/2/100+1)))/100; - seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6); + rt = max_sectors - resync; /* number of remaining sectors */ + sector_div(rt, db/32+1); + rt *= dt; + rt >>= 5; + + seq_printf(seq, " finish=%lu.%lumin", (unsigned long)rt / 60, + ((unsigned long)rt % 60)/6); seq_printf(seq, " speed=%ldK/sec", db/2/dt); } |