| From 4a5881f6fb25115e7dd336733e0a17e038435309 Mon Sep 17 00:00:00 2001 |
| From: Young Xiao <YangX92@hotmail.com> |
| Date: Wed, 28 Nov 2018 12:36:39 +0000 |
| Subject: sunvdc: Do not spin in an infinite loop when vio_ldc_send() returns |
| EAGAIN |
| |
| [ 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 ad9749463d4f..ed4d6276e94f 100644 |
| --- a/drivers/block/sunvdc.c |
| +++ b/drivers/block/sunvdc.c |
| @@ -41,6 +41,8 @@ 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 { |
| @@ -427,6 +429,7 @@ 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; |
| @@ -439,6 +442,8 @@ 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 |
| |
