* [PATCH] vhost: reduce stack usage in log_used
@ 2020-09-11 15:09 Li Wang
2020-09-14 2:42 ` Jason Wang
0 siblings, 1 reply; 4+ messages in thread
From: Li Wang @ 2020-09-11 15:09 UTC (permalink / raw)
To: mst, jasowang; +Cc: kvm, virtualization, netdev, linux-kernel
Fix the warning: [-Werror=-Wframe-larger-than=]
drivers/vhost/vhost.c: In function log_used:
drivers/vhost/vhost.c:1906:1:
warning: the frame size of 1040 bytes is larger than 1024 bytes
Signed-off-by: Li Wang <li.wang@windriver.com>
---
drivers/vhost/vhost.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index b45519c..41769de 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1884,25 +1884,31 @@ static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
{
- struct iovec iov[64];
+ struct iovec *iov;
int i, ret;
if (!vq->iotlb)
return log_write(vq->log_base, vq->log_addr + used_offset, len);
+ iov = kcalloc(64, sizeof(*iov), GFP_KERNEL);
+ if (!iov)
+ return -ENOMEM;
+
ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
len, iov, 64, VHOST_ACCESS_WO);
if (ret < 0)
- return ret;
+ goto out;
for (i = 0; i < ret; i++) {
ret = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
iov[i].iov_len);
if (ret)
- return ret;
+ goto out;
}
- return 0;
+out:
+ kfree(iov);
+ return ret;
}
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] vhost: reduce stack usage in log_used
2020-09-11 15:09 [PATCH] vhost: reduce stack usage in log_used Li Wang
@ 2020-09-14 2:42 ` Jason Wang
2020-09-14 18:08 ` Li Wang
0 siblings, 1 reply; 4+ messages in thread
From: Jason Wang @ 2020-09-14 2:42 UTC (permalink / raw)
To: Li Wang; +Cc: mst, kvm, virtualization, netdev, linux-kernel
----- Original Message -----
> Fix the warning: [-Werror=-Wframe-larger-than=]
>
> drivers/vhost/vhost.c: In function log_used:
> drivers/vhost/vhost.c:1906:1:
> warning: the frame size of 1040 bytes is larger than 1024 bytes
>
> Signed-off-by: Li Wang <li.wang@windriver.com>
> ---
> drivers/vhost/vhost.c | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index b45519c..41769de 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -1884,25 +1884,31 @@ static int log_write_hva(struct vhost_virtqueue *vq,
> u64 hva, u64 len)
>
> static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
> {
> - struct iovec iov[64];
> + struct iovec *iov;
> int i, ret;
>
> if (!vq->iotlb)
> return log_write(vq->log_base, vq->log_addr + used_offset, len);
>
> + iov = kcalloc(64, sizeof(*iov), GFP_KERNEL);
> + if (!iov)
> + return -ENOMEM;
Let's preallocate it in e.g vhost_net_open().
We don't want to fail the log due to -ENOMEM.
Thanks
> +
> ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
> len, iov, 64, VHOST_ACCESS_WO);
> if (ret < 0)
> - return ret;
> + goto out;
>
> for (i = 0; i < ret; i++) {
> ret = log_write_hva(vq, (uintptr_t)iov[i].iov_base,
> iov[i].iov_len);
> if (ret)
> - return ret;
> + goto out;
> }
>
> - return 0;
> +out:
> + kfree(iov);
> + return ret;
> }
>
> int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
> --
> 2.7.4
>
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH] vhost: reduce stack usage in log_used
2020-09-14 2:42 ` Jason Wang
@ 2020-09-14 18:08 ` Li Wang
2020-09-15 7:53 ` Jason Wang
0 siblings, 1 reply; 4+ messages in thread
From: Li Wang @ 2020-09-14 18:08 UTC (permalink / raw)
To: mst, jasowang; +Cc: kvm, virtualization, netdev, linux-kernel
Fix the warning: [-Werror=-Wframe-larger-than=]
drivers/vhost/vhost.c: In function log_used:
drivers/vhost/vhost.c:1906:1:
warning: the frame size of 1040 bytes is larger than 1024 bytes
Signed-off-by: Li Wang <li.wang@windriver.com>
---
drivers/vhost/vhost.c | 2 +-
drivers/vhost/vhost.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index b45519c..31837a5
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1884,7 +1884,7 @@ static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
{
- struct iovec iov[64];
+ struct iovec *iov = vq->log_iov;
int i, ret;
if (!vq->iotlb)
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 9032d3c..5fe4b47
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -123,6 +123,7 @@ struct vhost_virtqueue {
/* Log write descriptors */
void __user *log_base;
struct vhost_log *log;
+ struct iovec log_iov[64];
/* Ring endianness. Defaults to legacy native endianness.
* Set to true when starting a modern virtio device. */
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] vhost: reduce stack usage in log_used
2020-09-14 18:08 ` Li Wang
@ 2020-09-15 7:53 ` Jason Wang
0 siblings, 0 replies; 4+ messages in thread
From: Jason Wang @ 2020-09-15 7:53 UTC (permalink / raw)
To: Li Wang, mst; +Cc: kvm, virtualization, netdev, linux-kernel
On 2020/9/15 上午2:08, Li Wang wrote:
> Fix the warning: [-Werror=-Wframe-larger-than=]
>
> drivers/vhost/vhost.c: In function log_used:
> drivers/vhost/vhost.c:1906:1:
> warning: the frame size of 1040 bytes is larger than 1024 bytes
>
> Signed-off-by: Li Wang <li.wang@windriver.com>
> ---
> drivers/vhost/vhost.c | 2 +-
> drivers/vhost/vhost.h | 1 +
> 2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index b45519c..31837a5
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -1884,7 +1884,7 @@ static int log_write_hva(struct vhost_virtqueue *vq, u64 hva, u64 len)
>
> static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
> {
> - struct iovec iov[64];
> + struct iovec *iov = vq->log_iov;
> int i, ret;
>
> if (!vq->iotlb)
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index 9032d3c..5fe4b47
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -123,6 +123,7 @@ struct vhost_virtqueue {
> /* Log write descriptors */
> void __user *log_base;
> struct vhost_log *log;
> + struct iovec log_iov[64];
>
> /* Ring endianness. Defaults to legacy native endianness.
> * Set to true when starting a modern virtio device. */
Acked-by: Jason Wang <jasowang@redhat.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-09-15 7:54 UTC | newest]
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2020-09-14 2:42 ` Jason Wang
2020-09-14 18:08 ` Li Wang
2020-09-15 7:53 ` Jason Wang
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