| Message ID | 20230522072535.1523740-4-linan666@huaweicloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | md: bugfix of writing raid sysfs | expand |
On Mon, May 22, 2023 at 12:27 AM <linan666@huaweicloud.com> wrote: > > From: Li Nan <linan122@huawei.com> > > check_decay_read_errors() is used to handle rdev->read_errors. But > read_errors is inc and read after check_decay_read_errors() is invoked > in fix_read_error(). > > Put all operations of read_errors into check_decay_read_errors() and > clean up unnecessary atomic_read of read_errors. If I understand correctly, this patch doesn't change the behavior of the code. If this is the case, I guess we don't really need it. The original code looks reasonable to me. Thanks, Song > > Suggested-by: Yu Kuai <yukuai3@huawei.com> > Signed-off-by: Li Nan <linan122@huawei.com> > --- > drivers/md/raid10.c | 41 ++++++++++++++++++++++++----------------- > 1 file changed, 24 insertions(+), 17 deletions(-) > > diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c > index 4fcfcb350d2b..d31eed17f186 100644 > --- a/drivers/md/raid10.c > +++ b/drivers/md/raid10.c > @@ -2655,23 +2655,24 @@ static void recovery_request_write(struct mddev *mddev, struct r10bio *r10_bio) > } > > /* > - * Used by fix_read_error() to decay the per rdev read_errors. > + * Used by fix_read_error() to decay the per rdev read_errors and check if > + * read_error > max_read_errors. > * We halve the read error count for every hour that has elapsed > * since the last recorded read error. > * > */ > -static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) > +static bool check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) > { > - long cur_time_mon; > + time64_t cur_time_mon = ktime_get_seconds(); > unsigned long hours_since_last; > - unsigned int read_errors = atomic_read(&rdev->read_errors); > - > - cur_time_mon = ktime_get_seconds(); > + unsigned int read_errors; > + unsigned int max_read_errors = > + atomic_read(&mddev->max_corr_read_errors); > > if (rdev->last_read_error == 0) { > /* first time we've seen a read error */ > rdev->last_read_error = cur_time_mon; > - return; > + goto increase; > } > > hours_since_last = (long)(cur_time_mon - > @@ -2684,10 +2685,25 @@ static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) > * just set read errors to 0. We do this to avoid > * overflowing the shift of read_errors by hours_since_last. > */ > + read_errors = atomic_read(&rdev->read_errors); > if (hours_since_last >= 8 * sizeof(read_errors)) > atomic_set(&rdev->read_errors, 0); > else > atomic_set(&rdev->read_errors, read_errors >> hours_since_last); > + > +increase: > + read_errors = atomic_inc_return(&rdev->read_errors); > + if (read_errors > max_read_errors) { > + pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n", > + mdname(mddev), rdev->bdev, > + read_errors, max_read_errors); > + pr_notice("md/raid10:%s: %pg: Failing raid device\n", > + mdname(mddev), rdev->bdev); > + md_error(mddev, rdev); > + return false; > + } > + > + return true; > } > > static int r10_sync_page_io(struct md_rdev *rdev, sector_t sector, > @@ -2727,7 +2743,6 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 > int sect = 0; /* Offset from r10_bio->sector */ > int sectors = r10_bio->sectors; > struct md_rdev *rdev; > - int max_read_errors = atomic_read(&mddev->max_corr_read_errors); > int d = r10_bio->devs[r10_bio->read_slot].devnum; > > /* still own a reference to this rdev, so it cannot > @@ -2740,15 +2755,7 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 > more fix_read_error() attempts */ > return; > > - check_decay_read_errors(mddev, rdev); > - atomic_inc(&rdev->read_errors); > - if (atomic_read(&rdev->read_errors) > max_read_errors) { > - pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n", > - mdname(mddev), rdev->bdev, > - atomic_read(&rdev->read_errors), max_read_errors); > - pr_notice("md/raid10:%s: %pg: Failing raid device\n", > - mdname(mddev), rdev->bdev); > - md_error(mddev, rdev); > + if (!check_decay_read_errors(mddev, rdev)) { > r10_bio->devs[r10_bio->read_slot].bio = IO_BLOCKED; > return; > } > -- > 2.31.1 >
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 4fcfcb350d2b..d31eed17f186 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2655,23 +2655,24 @@ static void recovery_request_write(struct mddev *mddev, struct r10bio *r10_bio) } /* - * Used by fix_read_error() to decay the per rdev read_errors. + * Used by fix_read_error() to decay the per rdev read_errors and check if + * read_error > max_read_errors. * We halve the read error count for every hour that has elapsed * since the last recorded read error. * */ -static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) +static bool check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) { - long cur_time_mon; + time64_t cur_time_mon = ktime_get_seconds(); unsigned long hours_since_last; - unsigned int read_errors = atomic_read(&rdev->read_errors); - - cur_time_mon = ktime_get_seconds(); + unsigned int read_errors; + unsigned int max_read_errors = + atomic_read(&mddev->max_corr_read_errors); if (rdev->last_read_error == 0) { /* first time we've seen a read error */ rdev->last_read_error = cur_time_mon; - return; + goto increase; } hours_since_last = (long)(cur_time_mon - @@ -2684,10 +2685,25 @@ static void check_decay_read_errors(struct mddev *mddev, struct md_rdev *rdev) * just set read errors to 0. We do this to avoid * overflowing the shift of read_errors by hours_since_last. */ + read_errors = atomic_read(&rdev->read_errors); if (hours_since_last >= 8 * sizeof(read_errors)) atomic_set(&rdev->read_errors, 0); else atomic_set(&rdev->read_errors, read_errors >> hours_since_last); + +increase: + read_errors = atomic_inc_return(&rdev->read_errors); + if (read_errors > max_read_errors) { + pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n", + mdname(mddev), rdev->bdev, + read_errors, max_read_errors); + pr_notice("md/raid10:%s: %pg: Failing raid device\n", + mdname(mddev), rdev->bdev); + md_error(mddev, rdev); + return false; + } + + return true; } static int r10_sync_page_io(struct md_rdev *rdev, sector_t sector, @@ -2727,7 +2743,6 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 int sect = 0; /* Offset from r10_bio->sector */ int sectors = r10_bio->sectors; struct md_rdev *rdev; - int max_read_errors = atomic_read(&mddev->max_corr_read_errors); int d = r10_bio->devs[r10_bio->read_slot].devnum; /* still own a reference to this rdev, so it cannot @@ -2740,15 +2755,7 @@ static void fix_read_error(struct r10conf *conf, struct mddev *mddev, struct r10 more fix_read_error() attempts */ return; - check_decay_read_errors(mddev, rdev); - atomic_inc(&rdev->read_errors); - if (atomic_read(&rdev->read_errors) > max_read_errors) { - pr_notice("md/raid10:%s: %pg: Raid device exceeded read_error threshold [cur %d:max %d]\n", - mdname(mddev), rdev->bdev, - atomic_read(&rdev->read_errors), max_read_errors); - pr_notice("md/raid10:%s: %pg: Failing raid device\n", - mdname(mddev), rdev->bdev); - md_error(mddev, rdev); + if (!check_decay_read_errors(mddev, rdev)) { r10_bio->devs[r10_bio->read_slot].bio = IO_BLOCKED; return; }