lkml.org 
[lkml]   [2019]   [Feb]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.9 027/137] sunvdc: Do not spin in an infinite loop when vio_ldc_send() returns EAGAIN
Date
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit a11f6ca9aef989b56cd31ff4ee2af4fb31a172ec ]

__vdc_tx_trigger should only loop on EAGAIN a finite
number of times.

See commit adddc32d6fde ("sunvnet: Do not spin in an
infinite loop when vio_ldc_send() returns EAGAIN") for detail.

Signed-off-by: Young Xiao <YangX92@hotmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/block/sunvdc.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index cab157331c4e..c6d43a2a807d 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -40,6 +40,8 @@ MODULE_VERSION(DRV_MODULE_VERSION);
#define WAITING_FOR_GEN_CMD 0x04
#define WAITING_FOR_ANY -1

+#define VDC_MAX_RETRIES 10
+
static struct workqueue_struct *sunvdc_wq;

struct vdc_req_entry {
@@ -419,6 +421,7 @@ static int __vdc_tx_trigger(struct vdc_port *port)
.end_idx = dr->prod,
};
int err, delay;
+ int retries = 0;

hdr.seq = dr->snd_nxt;
delay = 1;
@@ -431,6 +434,8 @@ static int __vdc_tx_trigger(struct vdc_port *port)
udelay(delay);
if ((delay <<= 1) > 128)
delay = 128;
+ if (retries++ > VDC_MAX_RETRIES)
+ break;
} while (err == -EAGAIN);

if (err == -ENOTCONN)
--
2.19.1


\
 
 \ /
  Last update: 2019-02-11 16:20    [W:0.346 / U:5.792 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site