From: Aurelien Aptel <aaptel@suse.com>
Date: Thu, 4 Mar 2021 17:51:48 +0000
Subject: [PATCH] cifs: ask for more credit on async read/write code paths
Git-commit: 88fd98a2306755b965e4f4567f84e73db3b6738c
References: bsc#1190317
Patch-mainline: v5.12-rc3

When doing a large read or write workload we only
very gradually increase the number of credits
which can cause problems with parallelizing large i/o
(I/O ramps up more slowly than it should for large
read/write workloads) especially with multichannel
when the number of credits on the secondary channels
starts out low (e.g. less than about 130) or when
recovering after server throttled back the number
of credit.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
 fs/cifs/smb2pdu.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 4bbb6126b14d..2199a9bfae8f 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -4041,8 +4041,7 @@ smb2_async_readv(struct cifs_readdata *rdata)
 	if (rdata->credits.value > 0) {
 		shdr->CreditCharge = cpu_to_le16(DIV_ROUND_UP(rdata->bytes,
 						SMB2_MAX_BUFFER_SIZE));
-		shdr->CreditRequest =
-			cpu_to_le16(le16_to_cpu(shdr->CreditCharge) + 1);
+		shdr->CreditRequest = cpu_to_le16(le16_to_cpu(shdr->CreditCharge) + 8);
 
 		rc = adjust_credits(server, &rdata->credits, rdata->bytes);
 		if (rc)
@@ -4348,8 +4347,7 @@ smb2_async_writev(struct cifs_writedata *wdata,
 	if (wdata->credits.value > 0) {
 		shdr->CreditCharge = cpu_to_le16(DIV_ROUND_UP(wdata->bytes,
 						    SMB2_MAX_BUFFER_SIZE));
-		shdr->CreditRequest =
-			cpu_to_le16(le16_to_cpu(shdr->CreditCharge) + 1);
+		shdr->CreditRequest = cpu_to_le16(le16_to_cpu(shdr->CreditCharge) + 8);
 
 		rc = adjust_credits(server, &wdata->credits, wdata->bytes);
 		if (rc)
-- 
2.33.0