[Devel] [PATCH RHEL7 COMMIT] fs/fuse kio: remove useless pcs_cs initialization

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-957.12.2.vz7.96.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-957.12.2.vz7.96.7
------>
commit 7b072c6a173c6142bf4205c2c82b87651228c1fa
Author: Pavel Butsykin <pbutsykin at virtuozzo.com>
Date:   Fri May 24 18:55:00 2019 +0300

    fs/fuse kio: remove useless pcs_cs initialization
    
    It's not necessary to initialize cs data with zeros if the allocation is done
    by kzalloc().
    
    Signed-off-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
    
    =====================
    Patchset description:
    
    Statistics for vstorage kernel fast-path
    
    Vstorage provides plenty of statistics information via 'vstorage -c cl mnt-top',
    but when it comes kernel fast-path, it doesn't work. All because mnt-top
    command collects information from .vstorage.info directory, where vstorage-mount
    provides a lot of different statistical information in the form of files, but
    it was not implemented for for fast-path.
    
    This patch-set is aimed to implementation of the support of some statistics
    inforamtion files from .vstorage.info:
      cs_stats
      fstat
      fstat_lat
      iostat
      requests
    Which will be located at "/sys/fs/fuse/connections/*mnt_id*/kio_stat/". This
    will be enough to maintain vstorage mnt-top command for fast-path mount points.
    
    https://pmc.acronis.com/browse/VSTOR-20979
    
    Acked-by: Alexey Kuznetsov <kuznet at virtuozzo.com>
    
    Pavel Butsykin (14):
      fs/fuse: add conn_ctl to fuse_conn struct
      fs/fuse kio: create sysfs stat directory
      fs/fuse kio: implement iostat statistics info
      fs/fuse kio: make interface pcs_kio_file_list() for listing kio files
      fs/fuse kio: make interface pcs_kio_req_list() for listing kio reqs
      fs/fuse kio: add retry counter for kio requests
      fs/fuse kio: implement pcs_strerror()
      fs/fuse kio: implement requests statistics info
      fs/fuse kio: implement fstat statistics info
      fs/fuse kio: implement fstat_lat statistics info
      fs/fuse kio: remove useless pcs_cs initialization
      fs/fuse kio: implement cs statistics accounting
      fs/fuse kio: convert rpc state id to string
      fs/fuse kio: implement cs_stats statistics info
---
 fs/fuse/kio/pcs/pcs_cs.c | 22 +---------------------
 1 file changed, 1 insertion(+), 21 deletions(-)

diff --git a/fs/fuse/kio/pcs/pcs_cs.c b/fs/fuse/kio/pcs/pcs_cs.c
index 16992eb50e8d..64b0229e9bee 100644
--- a/fs/fuse/kio/pcs/pcs_cs.c
+++ b/fs/fuse/kio/pcs/pcs_cs.c
@@ -59,45 +59,25 @@ struct pcs_cs *pcs_cs_alloc(struct pcs_cs_set *css,
 	INIT_LIST_HEAD(&cs->lru_link);
 	spin_lock_init(&cs->lock);
 	cs->css = css;
-	cs->in_flight = 0;
 	cs->cwnd = PCS_CS_INIT_CWND;
 	cs->eff_cwnd = PCS_CS_INIT_CWND;
 	cs->ssthresh = PCS_CS_INIT_CWND;
-	cs->cwr_state = 0;
-	atomic_set(&cs->latency_avg, 0);
-	cs->net_latency_avg = 0;
-	cs->last_latency = 0;
-	cs->latency_stamp = 0;
-	cs->net_latency_stamp = 0;
-	cs->idle_stamp = 0;
-	cs->in_flight_hwm = 0;
-	cs->in_flight_hwm_stamp = 0;
+
 	pcs_cs_init_cong_queue(cs);
 	pcs_cs_init_active_list(cs);
 
 	cs->io_prio = -1;
-	cs->mds_flags = 0;
-	cs->io_prio_stamp = 0;
 
 	INIT_LIST_HEAD(&cs->flow_lru);
-	cs->nflows = 0;
-
-	cs->state = 0;
-	cs->use_count = 0;
-	cs->is_dead = 0;
 	INIT_LIST_HEAD(&cs->bl_link);
 
-	cs->addr_serno = 0;
-
 	cs->rpc = pcs_rpc_create(&cc->eng, &cn_rpc_params, &cn_rpc_ops);
 	if (cs->rpc == NULL) {
 		kfree(cs);
 		return NULL;
 	}
 	cs->rpc->private = cs;
-	cs->nmaps = 0;
 	INIT_LIST_HEAD(&cs->map_list);
-	memset(&cs->stat, 0, sizeof(cs->stat));
 	return cs;
 }