[Devel] [PATCH VZ9 1/2] fs/fuse/kio: finish cleanup of unused flow detection code

[Alexey Kuznetsov]

It was not clean which was not obvious until QA detected
significant drop in performance because small ioreqs
were accounted as 512k ones.

This patch goes together with "fs/fuse kio: remove unused flow detection code",
can be merged at the next port.

Signed-off-by: Alexey Kuznetsov <kuznet at virtuozzo.com>
---
 fs/fuse/kio/pcs/pcs_cs.c  |  2 --
 fs/fuse/kio/pcs/pcs_map.c | 25 ++++++-------------------
 fs/fuse/kio/pcs/pcs_req.h |  2 --
 3 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/fs/fuse/kio/pcs/pcs_cs.c b/fs/fuse/kio/pcs/pcs_cs.c
index 275fc8b..73476f5 100644
--- a/fs/fuse/kio/pcs/pcs_cs.c
+++ b/fs/fuse/kio/pcs/pcs_cs.c
@@ -699,8 +699,6 @@ static void do_cs_submit(struct pcs_cs *cs, struct pcs_int_request *ireq)
 		ioh->fiemap_count = PCS_FIEMAP_CHUNK_COUNT;
 	memset(&ioh->sync, 0, sizeof(ioh->sync));
 
-	if (ireq->flags & IREQ_F_SEQ)
-		ioh->sync.misc = PCS_CS_IO_SEQ;
 	if (ireq->dentry->no_csum_on_read)
                 ioh->sync.misc |= PCS_CS_IO_NOCSUM;
 	if ((ireq->dentry->fileinfo.attr.attrib & PCS_FATTR_IMMEDIATE_WRITE) || ireq->dentry->no_write_delay)
diff --git a/fs/fuse/kio/pcs/pcs_map.c b/fs/fuse/kio/pcs/pcs_map.c
index 3e2a00b..915b074 100644
--- a/fs/fuse/kio/pcs/pcs_map.c
+++ b/fs/fuse/kio/pcs/pcs_map.c
@@ -1474,7 +1474,7 @@ static void pcs_cs_deaccount(struct pcs_int_request *ireq, struct pcs_cs * cs, i
 			ireq->iochunk.cmd == PCS_REQ_T_FIEMAP)
 			cost = PCS_CS_HOLE_WEIGHT;
 		else
-			cost = (ireq->flags & IREQ_F_RND_WEIGHT) ? 512*1024 : cong_roundup(ireq->iochunk.size);
+			cost = cong_roundup(ireq->iochunk.size);
 	} else
 		cost = PCS_CS_FLUSH_WEIGHT;
 
@@ -1877,11 +1877,8 @@ static int select_cs_for_read(struct pcs_cluster_core *cc, struct pcs_cs_list *
 	else if (io_locality == 0 && local_mask != local_busy_mask) {
 		selected = local_idx;
 		io_cost = local_min / 16;
-	} else if (get_io_tweaks(cc) & PCS_TWEAK_IGNORE_SEQUENTIAL)
-		selected = remote_idx;
-	else {
+	} else
 		selected = remote_idx;
-	}
 
 	/* Add penalty. The result of current decision will reflect itself in latency
 	 * after at least one round-trip time. Penalty poisons weight until that moment.
@@ -2061,15 +2058,10 @@ static int pcs_cslist_submit_read(struct pcs_int_request *ireq, struct pcs_cs_li
 			}
 		}
 
-		sreq->flags &= ~(IREQ_F_RND_WEIGHT | IREQ_F_SEQ);
-		if (ireq->iochunk.cmd != PCS_REQ_T_READ) {
+		if (ireq->iochunk.cmd != PCS_REQ_T_READ)
 			weight = PCS_CS_HOLE_WEIGHT;
-		} else if (sreq->iochunk.size >= 512*1024) {
+		else
 			weight = cong_roundup(sreq->iochunk.size);
-		} else {
-			sreq->flags |= IREQ_F_RND_WEIGHT;
-			weight = 512*1024;
-		}
 
 		cs_increment_in_flight(cs, weight);
 		allot -= weight;
@@ -2226,15 +2218,10 @@ static int pcs_cslist_submit_write(struct pcs_int_request *ireq, struct pcs_cs_l
 			}
 		}
 
-		sreq->flags &= ~(IREQ_F_RND_WEIGHT | IREQ_F_SEQ);
-		if (ireq->iochunk.cmd != PCS_REQ_T_WRITE) {
+		if (ireq->iochunk.cmd != PCS_REQ_T_WRITE)
 			weight = PCS_CS_HOLE_WEIGHT;
-		} else if (sreq->iochunk.size > 512*1024) {
+		else
 			weight = cong_roundup(sreq->iochunk.size);
-		} else {
-			weight = 512*1024;
-			sreq->flags |= IREQ_F_RND_WEIGHT;
-		}
 
 		for (i = 0; i < csl->nsrv; i++)
 			cs_increment_in_flight(csl->cs[i].cslink.cs, weight);
diff --git a/fs/fuse/kio/pcs/pcs_req.h b/fs/fuse/kio/pcs/pcs_req.h
index 00af53a..a8c9c9b 100644
--- a/fs/fuse/kio/pcs/pcs_req.h
+++ b/fs/fuse/kio/pcs/pcs_req.h
@@ -114,9 +114,7 @@ struct pcs_int_request
 	int			flags;
 #define IREQ_F_FATAL		1
 #define IREQ_F_ONCE		2
-#define IREQ_F_RND_WEIGHT	8
 #define IREQ_F_CACHED		0x10
-#define IREQ_F_SEQ		0x20
 #define IREQ_F_MAPPED		0x40
 #define IREQ_F_MAP_REQUIRED	0x80
 #define IREQ_F_LOC_TOKEN	0x100
-- 
1.8.3.1