On Thu, 2020-01-16 at 05:38 -0500, xiubli@xxxxxxxxxx wrote: > From: Xiubo Li <xiubli@xxxxxxxxxx> > > item total sum_lat(us) avg_lat(us) > ----------------------------------------------------- > read 73 3590000 49178082 > > URL: https://tracker.ceph.com/issues/43215 > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > --- > fs/ceph/addr.c | 15 ++++++++++++++- > fs/ceph/debugfs.c | 13 +++++++++++++ > fs/ceph/file.c | 25 +++++++++++++++++++++++++ > fs/ceph/mds_client.c | 25 ++++++++++++++++++++++++- > fs/ceph/mds_client.h | 7 +++++++ > include/linux/ceph/osd_client.h | 2 +- > net/ceph/osd_client.c | 9 ++++++++- > 7 files changed, 92 insertions(+), 4 deletions(-) > > diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c > index 29d4513eff8c..479ecd0a6e9d 100644 > --- a/fs/ceph/addr.c > +++ b/fs/ceph/addr.c > @@ -190,6 +190,8 @@ static int ceph_do_readpage(struct file *filp, struct page *page) > struct inode *inode = file_inode(filp); > struct ceph_inode_info *ci = ceph_inode(inode); > struct ceph_fs_client *fsc = ceph_inode_to_client(inode); > + struct ceph_client_metric *metric = &fsc->mdsc->metric; > + s64 latency; > int err = 0; > u64 off = page_offset(page); > u64 len = PAGE_SIZE; > @@ -221,7 +223,7 @@ static int ceph_do_readpage(struct file *filp, struct page *page) > err = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode), > &ci->i_layout, off, &len, > ci->i_truncate_seq, ci->i_truncate_size, > - &page, 1, 0); > + &page, 1, 0, &latency); > if (err == -ENOENT) > err = 0; > if (err < 0) { > @@ -241,6 +243,9 @@ static int ceph_do_readpage(struct file *filp, struct page *page) > ceph_readpage_to_fscache(inode, page); > > out: > + if (latency) > + ceph_mdsc_update_read_latency(metric, latency); > + > return err < 0 ? err : 0; > } > > @@ -260,6 +265,8 @@ static int ceph_readpage(struct file *filp, struct page *page) > static void finish_read(struct ceph_osd_request *req) > { > struct inode *inode = req->r_inode; > + struct ceph_fs_client *fsc = ceph_inode_to_client(inode); > + struct ceph_client_metric *metric = &fsc->mdsc->metric; > struct ceph_osd_data *osd_data; > int rc = req->r_result <= 0 ? req->r_result : 0; > int bytes = req->r_result >= 0 ? req->r_result : 0; > @@ -297,6 +304,12 @@ static void finish_read(struct ceph_osd_request *req) > put_page(page); > bytes -= PAGE_SIZE; > } > + > + if (rc >= 0 || rc == -ENOENT) { > + s64 latency = jiffies - req->r_start_stamp; > + ceph_mdsc_update_read_latency(metric, latency); > + } > + > kfree(osd_data->pages); > } > > diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c > index c132fdb40d53..8200bf025ccd 100644 > --- a/fs/ceph/debugfs.c > +++ b/fs/ceph/debugfs.c > @@ -128,8 +128,21 @@ static int metric_show(struct seq_file *s, void *p) > { > struct ceph_fs_client *fsc = s->private; > struct ceph_mds_client *mdsc = fsc->mdsc; > + s64 total, sum, avg = 0; > int i; > > + seq_printf(s, "item total sum_lat(us) avg_lat(us)\n"); > + seq_printf(s, "-----------------------------------------------------\n"); > + > + spin_lock(&mdsc->metric.read_lock); > + total = atomic64_read(&mdsc->metric.total_reads), > + sum = timespec64_to_ns(&mdsc->metric.read_latency_sum); > + spin_unlock(&mdsc->metric.read_lock); > + avg = total ? sum / total : 0; > + seq_printf(s, "%-14s%-12lld%-16lld%lld\n", "read", > + total, sum / NSEC_PER_USEC, avg / NSEC_PER_USEC); > + > + seq_printf(s, "\n"); > seq_printf(s, "item total miss hit\n"); > seq_printf(s, "-------------------------------------------------\n"); > > diff --git a/fs/ceph/file.c b/fs/ceph/file.c > index c78dfbbb7b91..f479b699db14 100644 > --- a/fs/ceph/file.c > +++ b/fs/ceph/file.c > @@ -588,6 +588,7 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to, > struct inode *inode = file_inode(file); > struct ceph_inode_info *ci = ceph_inode(inode); > struct ceph_fs_client *fsc = ceph_inode_to_client(inode); > + struct ceph_client_metric *metric = &fsc->mdsc->metric; > struct ceph_osd_client *osdc = &fsc->client->osdc; > ssize_t ret; > u64 off = iocb->ki_pos; > @@ -660,6 +661,11 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to, > ret = ceph_osdc_start_request(osdc, req, false); > if (!ret) > ret = ceph_osdc_wait_request(osdc, req); > + > + if (ret >= 0 || ret == -ENOENT || ret == -ETIMEDOUT) { > + s64 latency = jiffies - req->r_start_stamp; > + ceph_mdsc_update_read_latency(metric, latency); > + } > ceph_osdc_put_request(req); > > i_size = i_size_read(inode); > @@ -798,13 +804,24 @@ static void ceph_aio_complete_req(struct ceph_osd_request *req) > struct inode *inode = req->r_inode; > struct ceph_aio_request *aio_req = req->r_priv; > struct ceph_osd_data *osd_data = osd_req_op_extent_osd_data(req, 0); > + struct ceph_fs_client *fsc = ceph_inode_to_client(inode); > + struct ceph_client_metric *metric = &fsc->mdsc->metric; > > BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_BVECS); > BUG_ON(!osd_data->num_bvecs); > + BUG_ON(!aio_req); > > dout("ceph_aio_complete_req %p rc %d bytes %u\n", > inode, rc, osd_data->bvec_pos.iter.bi_size); > > + /* r_start_stamp == 0 means the request was not submitted */ > + if (req->r_start_stamp && (rc >= 0 || rc == -ENOENT)) { > + s64 latency = jiffies - req->r_start_stamp; > + > + if (!aio_req->write) > + ceph_mdsc_update_read_latency(metric, latency); > + } > + > if (rc == -EOLDSNAPC) { > struct ceph_aio_work *aio_work; > BUG_ON(!aio_req->write); > @@ -933,6 +950,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter, > struct inode *inode = file_inode(file); > struct ceph_inode_info *ci = ceph_inode(inode); > struct ceph_fs_client *fsc = ceph_inode_to_client(inode); > + struct ceph_client_metric *metric = &fsc->mdsc->metric; > struct ceph_vino vino; > struct ceph_osd_request *req; > struct bio_vec *bvecs; > @@ -1049,6 +1067,13 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter, > if (!ret) > ret = ceph_osdc_wait_request(&fsc->client->osdc, req); > > + if ((ret >= 0 || ret == -ENOENT || ret == -ETIMEDOUT)) { > + s64 latency = jiffies - req->r_start_stamp; > + > + if (!write) > + ceph_mdsc_update_read_latency(metric, latency); > + } > + > size = i_size_read(inode); > if (!write) { > if (ret == -ENOENT) > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c > index 141c1c03636c..dc2cda55a5a5 100644 > --- a/fs/ceph/mds_client.c > +++ b/fs/ceph/mds_client.c > @@ -4093,6 +4093,25 @@ static void maybe_recover_session(struct ceph_mds_client *mdsc) > ceph_force_reconnect(fsc->sb); > } > > +/* > + * metric helpers > + */ > +void ceph_mdsc_update_read_latency(struct ceph_client_metric *m, > + s64 latency) > +{ > + struct timespec64 ts; > + > + if (!m) > + return; > + > + jiffies_to_timespec64(latency, &ts); > + > + spin_lock(&m->read_lock); > + atomic64_inc(&m->total_reads); > + m->read_latency_sum = timespec64_add(m->read_latency_sum, ts); > + spin_unlock(&m->read_lock); > +} > + > /* > * delayed work -- periodically trim expired leases, renew caps with mds > */ > @@ -4182,13 +4201,17 @@ static int ceph_mdsc_metric_init(struct ceph_client_metric *metric) > atomic64_set(&metric->total_dentries, 0); > ret = percpu_counter_init(&metric->d_lease_hit, 0, GFP_KERNEL); > if (ret) > - return ret; > + return ret;; > ret = percpu_counter_init(&metric->d_lease_mis, 0, GFP_KERNEL); > if (ret) { > percpu_counter_destroy(&metric->d_lease_hit); > return ret; > } > > + spin_lock_init(&metric->read_lock); > + memset(&metric->read_latency_sum, 0, sizeof(struct timespec64)); > + atomic64_set(&metric->total_reads, 0); > + > return 0; > } > > diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h > index ba74ff74c59c..cdc59037ef14 100644 > --- a/fs/ceph/mds_client.h > +++ b/fs/ceph/mds_client.h > @@ -366,6 +366,10 @@ struct ceph_client_metric { > atomic64_t total_dentries; > struct percpu_counter d_lease_hit; > struct percpu_counter d_lease_mis; > + > + spinlock_t read_lock; > + atomic64_t total_reads; > + struct timespec64 read_latency_sum; > }; > > /* > @@ -549,4 +553,7 @@ extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, > extern int ceph_trim_caps(struct ceph_mds_client *mdsc, > struct ceph_mds_session *session, > int max_caps); > + > +extern void ceph_mdsc_update_read_latency(struct ceph_client_metric *m, > + s64 latency); > #endif > diff --git a/include/linux/ceph/osd_client.h b/include/linux/ceph/osd_client.h > index 5a62dbd3f4c2..43e4240d88e7 100644 > --- a/include/linux/ceph/osd_client.h > +++ b/include/linux/ceph/osd_client.h > @@ -515,7 +515,7 @@ extern int ceph_osdc_readpages(struct ceph_osd_client *osdc, > u64 off, u64 *plen, > u32 truncate_seq, u64 truncate_size, > struct page **pages, int nr_pages, > - int page_align); > + int page_align, s64 *latency); > > extern int ceph_osdc_writepages(struct ceph_osd_client *osdc, > struct ceph_vino vino, > diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c > index b68b376d8c2f..62eb758f2474 100644 > --- a/net/ceph/osd_client.c > +++ b/net/ceph/osd_client.c > @@ -5238,11 +5238,15 @@ int ceph_osdc_readpages(struct ceph_osd_client *osdc, > struct ceph_vino vino, struct ceph_file_layout *layout, > u64 off, u64 *plen, > u32 truncate_seq, u64 truncate_size, > - struct page **pages, int num_pages, int page_align) > + struct page **pages, int num_pages, int page_align, > + s64 *latency) > { > struct ceph_osd_request *req; > int rc = 0; > > + if (latency) > + *latency = 0; > + > dout("readpages on ino %llx.%llx on %llu~%llu\n", vino.ino, > vino.snap, off, *plen); > req = ceph_osdc_new_request(osdc, layout, vino, off, plen, 0, 1, > @@ -5263,6 +5267,9 @@ int ceph_osdc_readpages(struct ceph_osd_client *osdc, > if (!rc) > rc = ceph_osdc_wait_request(osdc, req); > > + if (latency && (rc >= 0 || rc == -ENOENT || rc == -ETIMEDOUT)) > + *latency = jiffies - req->r_start_stamp; > + > ceph_osdc_put_request(req); > dout("readpages result %d\n", rc); > return rc; This function is only called from ceph_do_readpage(). I think it'd be better to just turn ceph_osdc_readpages into ceph_osdc_readpages_submit, make it not wait on the req and have it return a pointer to the req with a reference held. Then the caller could then handle the waiting and do the latency calculation afterward and we wouldn't need to add a new pointer argument here and push these details into libcephfs. -- Jeff Layton <jlayton@xxxxxxxxxx>
