[Devel] [PATCH 14/15] fs/fuse kio: implement cs_stats statistics info

[Pavel Butsykin]

This statistic shows information about all cs's, directed to show how much and
what type of load the chunk servers are loaded on. Made by analogy with
.vstorage.info/cs_stats statistics of user-mod client.

Signed-off-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
---
 fs/fuse/kio/pcs/fuse_stat.c | 73 +++++++++++++++++++++++++++++++++++++++++++++
 fs/fuse/kio/pcs/fuse_stat.h |  1 +
 2 files changed, 74 insertions(+)

diff --git a/fs/fuse/kio/pcs/fuse_stat.c b/fs/fuse/kio/pcs/fuse_stat.c
index 452bb4e9664c..edb124a00682 100644
--- a/fs/fuse/kio/pcs/fuse_stat.c
+++ b/fs/fuse/kio/pcs/fuse_stat.c
@@ -133,6 +133,71 @@ static inline unsigned long long fuse_val_cnt_max(struct fuse_val_cnt const* c)
 #define CNT_MIN(c)    fuse_val_cnt_min(&(c))
 #define CNT_MAX(c)    fuse_val_cnt_max(&(c))
 
+static int do_show_cs_stats(struct pcs_cs *cs, void *ctx)
+{
+	struct seq_file *m = ctx;
+	int rpc_state = cs->rpc ? cs->rpc->state : PCS_RPC_UNCONN;
+	unsigned int in_flight_avg = 0; /* TODO */
+	struct pcs_perf_stat_cnt iolat, netlat;
+	struct pcs_perf_rate_cnt read_ops_rate, write_ops_rate, sync_ops_rate;
+
+	spin_lock(&cs->stat.lock);
+	iolat = cs->stat.iolat;
+	netlat = cs->stat.netlat;
+	read_ops_rate = cs->stat.read_ops_rate;
+	write_ops_rate = cs->stat.write_ops_rate;
+	sync_ops_rate = cs->stat.sync_ops_rate;
+	spin_unlock(&cs->stat.lock);
+
+	seq_printf(m, "%-10llu %d=%-8s %-10llu %-10llu %-10llu %-12llu %-12llu %-12llu %-12llu %-10u\n",
+		NODE_ARGS(cs->id), rpc_state, pcs_rpc_state_name(rpc_state),
+		read_ops_rate.rate / STAT_TIMER_PERIOD,
+		write_ops_rate.rate / STAT_TIMER_PERIOD,
+		sync_ops_rate.rate / STAT_TIMER_PERIOD,
+		netlat.avg, pcs_perfcounter_stat_max(&netlat),
+		iolat.avg, pcs_perfcounter_stat_max(&iolat),
+		in_flight_avg);
+	return 0;
+}
+
+static int pcs_fuse_cs_stats_show(struct seq_file *m, void *v)
+{
+	struct inode *inode = m->private;
+	struct pcs_cluster_core *cc;
+	struct pcs_fuse_stat *stat;
+
+	if (!inode)
+		return 0;
+
+	mutex_lock(&fuse_mutex);
+	stat = inode->i_private;
+	if (!stat) {
+		mutex_unlock(&fuse_mutex);
+		return 0;
+	}
+
+	seq_printf(m, "# csid     rpc        rd_ops     wr_ops     sync_ops   net_lat_avg  net_lat_max  io_lat_avg   io_lat_max   avg_in_flight\n");
+
+	cc = container_of(stat, struct pcs_cluster_core, stat);
+	pcs_cs_for_each_entry(&cc->css, do_show_cs_stats, m);
+
+	mutex_unlock(&fuse_mutex);
+
+	return 0;
+}
+
+static int pcs_fuse_cs_stats_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, pcs_fuse_cs_stats_show, inode);
+}
+
+static const struct file_operations pcs_fuse_cs_stats_ops = {
+	.owner   = THIS_MODULE,
+	.open    = pcs_fuse_cs_stats_open,
+	.read    = seq_read,
+	.llseek	 = seq_lseek,
+	.release = single_release,
+};
 
 #define MAX_PERCENT 100
 static int latency_npercl_format(struct fuse_lat_stat *s, u8 percl, char *buf,
@@ -528,6 +593,8 @@ static void pcs_fuse_stat_work(struct work_struct *w)
 
 	pcs_fuse_stat_files_up(cc);
 
+	pcs_cs_set_stat_up(&cc->css);
+
 	mod_delayed_work(cc->wq, &cc->stat.work, STAT_TIMER_PERIOD * HZ);
 }
 
@@ -615,6 +682,10 @@ void pcs_fuse_stat_init(struct pcs_fuse_stat *stat)
 	stat->fstat_lat = fuse_kio_add_dentry(stat->kio_stat, fc, "fstat_lat",
 					      S_IFREG | S_IRUSR, 1, NULL,
 					      &pcs_fuse_fstat_lat_ops, stat);
+
+	stat->cs_stats = fuse_kio_add_dentry(stat->kio_stat, fc, "cs_stats",
+					     S_IFREG | S_IRUSR, 1, NULL,
+					     &pcs_fuse_cs_stats_ops, stat);
 out:
 	mutex_unlock(&fuse_mutex);
 }
@@ -634,6 +705,8 @@ void pcs_fuse_stat_fini(struct pcs_fuse_stat *stat)
 			fuse_kio_rm_dentry(stat->fstat);
 		if (stat->fstat_lat)
 			fuse_kio_rm_dentry(stat->fstat_lat);
+		if (stat->cs_stats)
+			fuse_kio_rm_dentry(stat->cs_stats);
 		fuse_kio_rm_dentry(stat->kio_stat);
 	}
 	mutex_unlock(&fuse_mutex);
diff --git a/fs/fuse/kio/pcs/fuse_stat.h b/fs/fuse/kio/pcs/fuse_stat.h
index 32971cf77dc4..88033c0eecc5 100644
--- a/fs/fuse/kio/pcs/fuse_stat.h
+++ b/fs/fuse/kio/pcs/fuse_stat.h
@@ -35,6 +35,7 @@ struct pcs_fuse_stat {
 	struct dentry *requests;
 	struct dentry *fstat;
 	struct dentry *fstat_lat;
+	struct dentry *cs_stats;
 };
 
 enum {
-- 
2.15.1