Displaying 20 results from an estimated 1000 matches similar to: "[PATCH net-next 11/12] tools/virtio: copy READ/WRITE_ONCE"
2019 Nov 08
0
[PATCH 01/13] compiler.h: Split {READ, WRITE}_ONCE definitions out into rwonce.h
In preparation for allowing architectures to define their own
implementation of the 'READ_ONCE()' macro, move the generic
'{READ,WRITE}_ONCE()' definitions out of the unwieldy 'linux/compiler.h'
and into a new 'rwonce.h' header under 'asm-generic'.
Signed-off-by: Will Deacon <will at kernel.org>
---
include/asm-generic/Kbuild | 1 +
2016 May 15
0
[PATCH] tools/virtio: add inorder option
skips ring accesses but drops out of order support
At high level this follows alf design
https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/lib/alf_queue.c
but on most (single-threaded) benchmarks this seems to be slower than the layout
without index use.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
tools/virtio/ringtest/virtio_ring_0_9.c | 49
2016 May 15
0
[PATCH] tools/virtio: add inorder option
skips ring accesses but drops out of order support
At high level this follows alf design
https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/lib/alf_queue.c
but on most (single-threaded) benchmarks this seems to be slower than the layout
without index use.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
tools/virtio/ringtest/virtio_ring_0_9.c | 49
2016 Jan 21
1
[PATCH] tools/virtio: add ringtest utilities
This adds micro-benchmarks useful for tuning virtio ring layouts.
Three layouts are currently implemented:
- virtio 0.9 compatible one
- an experimental extension bypassing the ring index, polling ring
itself instead
- an experimental extension bypassing avail and used ring completely
Typical use:
sh run-on-all.sh perf stat -r 10 --log-fd 1 -- ./ring
It doesn't depend on the kernel
2016 Jan 21
1
[PATCH] tools/virtio: add ringtest utilities
This adds micro-benchmarks useful for tuning virtio ring layouts.
Three layouts are currently implemented:
- virtio 0.9 compatible one
- an experimental extension bypassing the ring index, polling ring
itself instead
- an experimental extension bypassing avail and used ring completely
Typical use:
sh run-on-all.sh perf stat -r 10 --log-fd 1 -- ./ring
It doesn't depend on the kernel
2017 Dec 05
0
[PATCH tip/core/rcu 21/21] drivers/vhost: Remove now-redundant read_barrier_depends()
On Tue, Dec 05, 2017 at 07:39:46PM +0100, Peter Zijlstra wrote:
> On Tue, Dec 05, 2017 at 08:31:20PM +0200, Michael S. Tsirkin wrote:
>
> > Apropos, READ_ONCE is now asymmetrical with WRITE_ONCE.
> >
> > I can read a pointer with READ_ONCE and be sure the value
> > is sane, but only if I also remember to put in smp_wmb before
> > WRITE_ONCE. Otherwise the
2019 Nov 08
15
[PATCH 00/13] Finish off [smp_]read_barrier_depends()
Hi all,
Although [smp_]read_barrier_depends() became part of READ_ONCE() in
commit 76ebbe78f739 ("locking/barriers: Add implicit
smp_read_barrier_depends() to READ_ONCE()"), it still limps on in the
Linux memory model with the sinister hope of attracting innocent new
users so that it becomes impossible to remove altogether.
Let's strike before it's too late: there's only
2018 Jan 25
2
[PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
Offset 128 overlaps the last word of the redzone.
Use 132 which is always beyond that.
Signed-off-by: Michael S. Tsirkin <mst at 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
+++
2018 Jan 25
2
[PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
Offset 128 overlaps the last word of the redzone.
Use 132 which is always beyond that.
Signed-off-by: Michael S. Tsirkin <mst at 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
+++
2020 Jun 30
0
[PATCH 18/18] arm64: lto: Strengthen READ_ONCE() to acquire when CLANG_LTO=y
When building with LTO, there is an increased risk of the compiler
converting an address dependency headed by a READ_ONCE() invocation
into a control dependency and consequently allowing for harmful
reordering by the CPU.
Ensure that such transformations are harmless by overriding the generic
READ_ONCE() definition with one that provides acquire semantics when
building with LTO.
Signed-off-by:
2020 Jul 10
0
[PATCH v3 19/19] arm64: lto: Strengthen READ_ONCE() to acquire when CONFIG_LTO=y
When building with LTO, there is an increased risk of the compiler
converting an address dependency headed by a READ_ONCE() invocation
into a control dependency and consequently allowing for harmful
reordering by the CPU.
Ensure that such transformations are harmless by overriding the generic
READ_ONCE() definition with one that provides acquire semantics when
building with LTO.
Signed-off-by:
2018 Jan 26
0
[PATCH net-next 12/12] tools/virtio: fix smp_mb on x86
On 2018?01?26? 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 at redhat.com>
> ---
> tools/virtio/ringtest/main.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/virtio/ringtest/main.h
2017 Oct 27
1
[PATCH v6] x86: use lock+addl for smp_mb()
mfence appears to be way slower than a locked instruction - let's use
lock+add unconditionally, as we always did on old 32-bit.
Results:
perf stat -r 10 -- ./virtio_ring_0_9 --sleep --host-affinity 0 --guest-affinity 0
Before:
0.922565990 seconds time elapsed ( +- 1.15% )
After:
0.578667024 seconds time elapsed
2017 Oct 27
1
[PATCH v6] x86: use lock+addl for smp_mb()
mfence appears to be way slower than a locked instruction - let's use
lock+add unconditionally, as we always did on old 32-bit.
Results:
perf stat -r 10 -- ./virtio_ring_0_9 --sleep --host-affinity 0 --guest-affinity 0
Before:
0.922565990 seconds time elapsed ( +- 1.15% )
After:
0.578667024 seconds time elapsed
2020 Jun 30
2
[PATCH 18/18] arm64: lto: Strengthen READ_ONCE() to acquire when CLANG_LTO=y
On Tue, Jun 30, 2020 at 7:39 PM Will Deacon <will at kernel.org> wrote:
> +#define __READ_ONCE(x) \
> +({ \
> + int atomic = 1; \
> + union { __unqual_scalar_typeof(x) __val; char __c[1]; } __u; \
> +
2020 Jun 30
2
[PATCH 18/18] arm64: lto: Strengthen READ_ONCE() to acquire when CLANG_LTO=y
On Tue, Jun 30, 2020 at 7:39 PM Will Deacon <will at kernel.org> wrote:
> +#define __READ_ONCE(x) \
> +({ \
> + int atomic = 1; \
> + union { __unqual_scalar_typeof(x) __val; char __c[1]; } __u; \
> +
2017 Oct 30
3
[locking/paravirt] static_key_disable_cpuslocked(): static key 'virt_spin_lock_key+0x0/0x20' used before call to jump_label_init()
On Sun, Oct 29, 2017 at 11:51:55PM +0100, Fengguang Wu wrote:
>Hi Linus,
>
>Up to now we see the below boot error/warnings when testing v4.14-rc6.
>
>They hit the RC release mainly due to various imperfections in 0day's
>auto bisection. So I manually list them here and CC the likely easy to
>debug ones to the corresponding maintainers in the followup emails.
>
2017 Oct 30
3
[locking/paravirt] static_key_disable_cpuslocked(): static key 'virt_spin_lock_key+0x0/0x20' used before call to jump_label_init()
On Sun, Oct 29, 2017 at 11:51:55PM +0100, Fengguang Wu wrote:
>Hi Linus,
>
>Up to now we see the below boot error/warnings when testing v4.14-rc6.
>
>They hit the RC release mainly due to various imperfections in 0day's
>auto bisection. So I manually list them here and CC the likely easy to
>debug ones to the corresponding maintainers in the followup emails.
>
2016 Jan 14
1
[v3,11/41] mips: reuse asm-generic/barrier.h
On Thu, Jan 14, 2016 at 01:45:44PM -0800, Leonid Yegoshin wrote:
> On 01/14/2016 01:34 PM, Paul E. McKenney wrote:
> >On Thu, Jan 14, 2016 at 12:46:43PM -0800, Leonid Yegoshin wrote:
> >>On 01/14/2016 12:15 PM, Peter Zijlstra wrote:
> >>>On Thu, Jan 14, 2016 at 11:42:02AM -0800, Leonid Yegoshin wrote:
> >>>>An the only point - please use an appropriate
2016 Jan 14
1
[v3,11/41] mips: reuse asm-generic/barrier.h
On Thu, Jan 14, 2016 at 01:45:44PM -0800, Leonid Yegoshin wrote:
> On 01/14/2016 01:34 PM, Paul E. McKenney wrote:
> >On Thu, Jan 14, 2016 at 12:46:43PM -0800, Leonid Yegoshin wrote:
> >>On 01/14/2016 12:15 PM, Peter Zijlstra wrote:
> >>>On Thu, Jan 14, 2016 at 11:42:02AM -0800, Leonid Yegoshin wrote:
> >>>>An the only point - please use an appropriate