* [PATCH net-next 09/12] tools/virtio: switch to __ptr_ring_empty
[not found] <1516923320-16959-1-git-send-email-mst@redhat.com>
@ 2018-01-25 23:36 ` Michael S. Tsirkin
2018-01-25 23:36 ` [PATCH net-next 10/12] tools/virtio: more stubs to fix tools build Michael S. Tsirkin
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Michael S. Tsirkin @ 2018-01-25 23:36 UTC (permalink / raw)
To: linux-kernel; +Cc: netdev, John Fastabend, David Miller, virtualization
We don't rely on lockless guarantees, but it
seems cleaner than inverting __ptr_ring_peek.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
tools/virtio/ringtest/ptr_ring.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/virtio/ringtest/ptr_ring.c b/tools/virtio/ringtest/ptr_ring.c
index e6e8130..477899c 100644
--- a/tools/virtio/ringtest/ptr_ring.c
+++ b/tools/virtio/ringtest/ptr_ring.c
@@ -187,7 +187,7 @@ bool enable_kick()
bool avail_empty()
{
- return !__ptr_ring_peek(&array);
+ return __ptr_ring_empty(&array);
}
bool use_buf(unsigned *lenp, void **bufp)
--
MST
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net-next 10/12] tools/virtio: more stubs to fix tools build
[not found] <1516923320-16959-1-git-send-email-mst@redhat.com>
2018-01-25 23:36 ` [PATCH net-next 09/12] tools/virtio: switch to __ptr_ring_empty Michael S. Tsirkin
@ 2018-01-25 23:36 ` Michael S. Tsirkin
2018-01-25 23:36 ` [PATCH net-next 11/12] tools/virtio: copy READ/WRITE_ONCE Michael S. Tsirkin
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Michael S. Tsirkin @ 2018-01-25 23:36 UTC (permalink / raw)
To: linux-kernel; +Cc: netdev, John Fastabend, David Miller, virtualization
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
tools/virtio/linux/kernel.h | 2 +-
tools/virtio/linux/thread_info.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
create mode 100644 tools/virtio/linux/thread_info.h
diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 395521a..fca8381 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -118,7 +118,7 @@ static inline void free_page(unsigned long addr)
#define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
-#define WARN_ON_ONCE(cond) ((cond) && fprintf (stderr, "WARNING\n"))
+#define WARN_ON_ONCE(cond) ((cond) ? fprintf (stderr, "WARNING\n") : 0)
#define min(x, y) ({ \
typeof(x) _min1 = (x); \
diff --git a/tools/virtio/linux/thread_info.h b/tools/virtio/linux/thread_info.h
new file mode 100644
index 0000000..e0f610d
--- /dev/null
+++ b/tools/virtio/linux/thread_info.h
@@ -0,0 +1 @@
+#define check_copy_size(A, B, C) (1)
--
MST
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net-next 11/12] tools/virtio: copy READ/WRITE_ONCE
[not found] <1516923320-16959-1-git-send-email-mst@redhat.com>
2018-01-25 23:36 ` [PATCH net-next 09/12] tools/virtio: switch to __ptr_ring_empty Michael S. Tsirkin
2018-01-25 23:36 ` [PATCH net-next 10/12] tools/virtio: more stubs to fix tools build Michael S. Tsirkin
@ 2018-01-25 23:36 ` Michael S. Tsirkin
2018-01-25 23:36 ` [PATCH net-next 12/12] tools/virtio: fix smp_mb on x86 Michael S. Tsirkin
[not found] ` <1516923320-16959-16-git-send-email-mst@redhat.com>
4 siblings, 0 replies; 6+ messages in thread
From: Michael S. Tsirkin @ 2018-01-25 23:36 UTC (permalink / raw)
To: linux-kernel; +Cc: netdev, John Fastabend, David Miller, virtualization
This is to make ptr_ring test build again.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
tools/virtio/ringtest/main.h | 57 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h
index 5706e07..593a328 100644
--- a/tools/virtio/ringtest/main.h
+++ b/tools/virtio/ringtest/main.h
@@ -134,4 +134,61 @@ static inline void busy_wait(void)
barrier(); \
} while (0)
+#if defined(__i386__) || defined(__x86_64__) || defined(__s390x__)
+#define smp_wmb() barrier()
+#else
+#define smp_wmb() smp_release()
+#endif
+
+#ifdef __alpha__
+#define smp_read_barrier_depends() smp_acquire()
+#else
+#define smp_read_barrier_depends() do {} while(0)
+#endif
+
+static __always_inline
+void __read_once_size(const volatile void *p, void *res, int size)
+{
+ switch (size) { \
+ case 1: *(unsigned char *)res = *(volatile unsigned char *)p; break; \
+ case 2: *(unsigned short *)res = *(volatile unsigned short *)p; break; \
+ case 4: *(unsigned int *)res = *(volatile unsigned int *)p; break; \
+ case 8: *(unsigned long long *)res = *(volatile unsigned long long *)p; break; \
+ default: \
+ barrier(); \
+ __builtin_memcpy((void *)res, (const void *)p, size); \
+ barrier(); \
+ } \
+}
+
+static __always_inline void __write_once_size(volatile void *p, void *res, int size)
+{
+ switch (size) {
+ case 1: *(volatile unsigned char *)p = *(unsigned char *)res; break;
+ case 2: *(volatile unsigned short *)p = *(unsigned short *)res; break;
+ case 4: *(volatile unsigned int *)p = *(unsigned int *)res; break;
+ case 8: *(volatile unsigned long long *)p = *(unsigned long long *)res; break;
+ default:
+ barrier();
+ __builtin_memcpy((void *)p, (const void *)res, size);
+ barrier();
+ }
+}
+
+#define READ_ONCE(x) \
+({ \
+ union { typeof(x) __val; char __c[1]; } __u; \
+ __read_once_size(&(x), __u.__c, sizeof(x)); \
+ smp_read_barrier_depends(); /* Enforce dependency ordering from x */ \
+ __u.__val; \
+})
+
+#define WRITE_ONCE(x, val) \
+({ \
+ union { typeof(x) __val; char __c[1]; } __u = \
+ { .__val = (typeof(x)) (val) }; \
+ __write_once_size(&(x), __u.__c, sizeof(x)); \
+ __u.__val; \
+})
+
#endif
--
MST
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
[not found] <1516923320-16959-1-git-send-email-mst@redhat.com>
` (2 preceding siblings ...)
2018-01-25 23:36 ` [PATCH net-next 11/12] tools/virtio: copy READ/WRITE_ONCE Michael S. Tsirkin
@ 2018-01-25 23:36 ` Michael S. Tsirkin
[not found] ` <1516923320-16959-16-git-send-email-mst@redhat.com>
4 siblings, 0 replies; 6+ messages in thread
From: Michael S. Tsirkin @ 2018-01-25 23:36 UTC (permalink / raw)
To: linux-kernel; +Cc: netdev, John Fastabend, David Miller, virtualization
Offset 128 overlaps the last word of the redzone.
Use 132 which is always beyond that.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
tools/virtio/ringtest/main.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h
index 593a328..301d59b 100644
--- a/tools/virtio/ringtest/main.h
+++ b/tools/virtio/ringtest/main.h
@@ -111,7 +111,7 @@ static inline void busy_wait(void)
}
#if defined(__x86_64__) || defined(__i386__)
-#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc")
+#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc")
#else
/*
* Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
--
MST
^ permalink raw reply related [flat|nested] 6+ messages in thread[parent not found: <1516923320-16959-16-git-send-email-mst@redhat.com>]
* Re: [PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
[not found] ` <1516923320-16959-16-git-send-email-mst@redhat.com>
@ 2018-01-26 3:56 ` Jason Wang
2018-01-26 13:45 ` Michael S. Tsirkin
0 siblings, 1 reply; 6+ messages in thread
From: Jason Wang @ 2018-01-26 3:56 UTC (permalink / raw)
To: Michael S. Tsirkin, linux-kernel
Cc: netdev, John Fastabend, David Miller, virtualization
On 2018年01月26日 07:36, Michael S. Tsirkin wrote:
> Offset 128 overlaps the last word of the redzone.
> Use 132 which is always beyond that.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> tools/virtio/ringtest/main.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h
> index 593a328..301d59b 100644
> --- a/tools/virtio/ringtest/main.h
> +++ b/tools/virtio/ringtest/main.h
> @@ -111,7 +111,7 @@ static inline void busy_wait(void)
> }
>
> #if defined(__x86_64__) || defined(__i386__)
> -#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc")
Just wonder did "rsp" work for __i386__ ?
Thanks
> +#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc")
> #else
> /*
> * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
2018-01-26 3:56 ` Jason Wang
@ 2018-01-26 13:45 ` Michael S. Tsirkin
0 siblings, 0 replies; 6+ messages in thread
From: Michael S. Tsirkin @ 2018-01-26 13:45 UTC (permalink / raw)
To: Jason Wang
Cc: netdev, virtualization, John Fastabend, linux-kernel,
David Miller
On Fri, Jan 26, 2018 at 11:56:14AM +0800, Jason Wang wrote:
>
>
> On 2018年01月26日 07:36, Michael S. Tsirkin wrote:
> > Offset 128 overlaps the last word of the redzone.
> > Use 132 which is always beyond that.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> > tools/virtio/ringtest/main.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h
> > index 593a328..301d59b 100644
> > --- a/tools/virtio/ringtest/main.h
> > +++ b/tools/virtio/ringtest/main.h
> > @@ -111,7 +111,7 @@ static inline void busy_wait(void)
> > }
> > #if defined(__x86_64__) || defined(__i386__)
> > -#define smp_mb() asm volatile("lock; addl $0,-128(%%rsp)" ::: "memory", "cc")
>
> Just wonder did "rsp" work for __i386__ ?
>
> Thanks
Oh you are right of course. Probably no one ever run this one on i386 :)
I'll add a patch on top as this is not a new bug.
> > +#define smp_mb() asm volatile("lock; addl $0,-132(%%rsp)" ::: "memory", "cc")
> > #else
> > /*
> > * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
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^ permalink raw reply [flat|nested] 6+ messages in thread