From: Jeff Layton <jlayton@kernel.org>
To: xiubli@redhat.com
Cc: idryomov@gmail.com, pdonnell@redhat.com, ceph-devel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] ceph: update the __update_latency helper
Date: Tue, 27 Apr 2021 14:38:41 -0400 [thread overview]
Message-ID: <aff17365129ead70f109d96adcf24484d1b12c46.camel@kernel.org> (raw)
In-Reply-To: <20210325032826.1725667-2-xiubli@redhat.com>
On Thu, 2021-03-25 at 11:28 +0800, xiubli@redhat.com wrote:
> From: Xiubo Li <xiubli@redhat.com>
>
> Let the __update_latency() helper choose the correcsponding members
> according to the metric_type.
>
> URL: https://tracker.ceph.com/issues/49913
> Signed-off-by: Xiubo Li <xiubli@redhat.com>
> ---
> fs/ceph/metric.c | 73 ++++++++++++++++++++++++++++++++++--------------
> 1 file changed, 52 insertions(+), 21 deletions(-)
>
> diff --git a/fs/ceph/metric.c b/fs/ceph/metric.c
> index 28b6b42ad677..f3e68db08760 100644
> --- a/fs/ceph/metric.c
> +++ b/fs/ceph/metric.c
> @@ -285,19 +285,56 @@ void ceph_metric_destroy(struct ceph_client_metric *m)
> ceph_put_mds_session(m->session);
> }
>
> -static inline void __update_latency(ktime_t *totalp, ktime_t *lsump,
> - ktime_t *min, ktime_t *max,
> - ktime_t *sq_sump, ktime_t lat)
> -{
> - ktime_t total, avg, sq, lsum;
> -
> - total = ++(*totalp);
> - lsum = (*lsump += lat);
> +typedef enum {
> + CEPH_METRIC_READ,
> + CEPH_METRIC_WRITE,
> + CEPH_METRIC_METADATA,
> +} metric_type;
> +
> +#define METRIC_UPDATE_MIN_MAX(min, max, new) \
> +{ \
> + if (unlikely(new < min)) \
> + min = new; \
> + if (unlikely(new > max)) \
> + max = new; \
> +}
>
> - if (unlikely(lat < *min))
> - *min = lat;
> - if (unlikely(lat > *max))
> - *max = lat;
> +static inline void __update_latency(struct ceph_client_metric *m,
> + metric_type type, ktime_t lat)
> +{
> + ktime_t total, avg, sq, lsum, *sq_sump;
> +
> + switch (type) {
> + case CEPH_METRIC_READ:
> + total = ++m->total_reads;
> + m->read_latency_sum += lat;
> + lsum = m->read_latency_sum;
> + METRIC_UPDATE_MIN_MAX(m->read_latency_min,
> + m->read_latency_max,
> + lat);
> + sq_sump = &m->read_latency_sq_sum;
> + break;
> + case CEPH_METRIC_WRITE:
> + total = ++m->total_writes;
> + m->write_latency_sum += lat;
> + lsum = m->write_latency_sum;
> + METRIC_UPDATE_MIN_MAX(m->write_latency_min,
> + m->write_latency_max,
> + lat);
> + sq_sump = &m->write_latency_sq_sum;
> + break;
> + case CEPH_METRIC_METADATA:
> + total = ++m->total_metadatas;
> + m->metadata_latency_sum += lat;
> + lsum = m->metadata_latency_sum;
> + METRIC_UPDATE_MIN_MAX(m->metadata_latency_min,
> + m->metadata_latency_max,
> + lat);
> + sq_sump = &m->metadata_latency_sq_sum;
> + break;
> + default:
> + return;
> + }
>
I'm not a fan of the above function. __update_latency gets called with
each of those values only once.
It seems like it'd be better to just open-code the above sections in the
respective ceph_update_*_metrics functions, and then have a helper
function for the part of __update_latency below this point. With that,
you wouldn't need the enum either.
> if (unlikely(total == 1))
> return;
> @@ -320,9 +357,7 @@ void ceph_update_read_metrics(struct ceph_client_metric *m,
> return;
>
> spin_lock(&m->read_metric_lock);
> - __update_latency(&m->total_reads, &m->read_latency_sum,
> - &m->read_latency_min, &m->read_latency_max,
> - &m->read_latency_sq_sum, lat);
> + __update_latency(m, CEPH_METRIC_READ, lat);
> spin_unlock(&m->read_metric_lock);
> }
>
> @@ -336,9 +371,7 @@ void ceph_update_write_metrics(struct ceph_client_metric *m,
> return;
>
> spin_lock(&m->write_metric_lock);
> - __update_latency(&m->total_writes, &m->write_latency_sum,
> - &m->write_latency_min, &m->write_latency_max,
> - &m->write_latency_sq_sum, lat);
> + __update_latency(m, CEPH_METRIC_WRITE, lat);
> spin_unlock(&m->write_metric_lock);
> }
>
> @@ -352,8 +385,6 @@ void ceph_update_metadata_metrics(struct ceph_client_metric *m,
> return;
>
> spin_lock(&m->metadata_metric_lock);
> - __update_latency(&m->total_metadatas, &m->metadata_latency_sum,
> - &m->metadata_latency_min, &m->metadata_latency_max,
> - &m->metadata_latency_sq_sum, lat);
> + __update_latency(m, CEPH_METRIC_METADATA, lat);
> spin_unlock(&m->metadata_metric_lock);
> }
--
Jeff Layton <jlayton@kernel.org>
next prev parent reply other threads:[~2021-04-27 18:38 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-25 3:28 [PATCH v2 0/2] ceph: add IO size metric support xiubli
2021-03-25 3:28 ` [PATCH v2 1/2] ceph: update the __update_latency helper xiubli
2021-04-27 18:38 ` Jeff Layton [this message]
2021-04-28 1:23 ` Xiubo Li
2021-03-25 3:28 ` [PATCH v2 2/2] ceph: add IO size metrics support xiubli
2021-04-27 18:41 ` Jeff Layton
2021-04-28 1:24 ` Xiubo Li
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