* RE: [PATCH] Input: hyperv-keyboard: Add the support of hibernation
From: Dexuan Cui @ 2019-09-30 22:09 UTC (permalink / raw)
To: dmitry.torokhov@gmail.com
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
sashal@kernel.org, linux-hyperv@vger.kernel.org,
linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley
In-Reply-To: <20190928003156.GU237523@dtor-ws>
> From: dmitry.torokhov@gmail.com <dmitry.torokhov@gmail.com>
> Sent: Friday, September 27, 2019 5:32 PM
> > ...
> > pm_wakeup_pending() is tested in a lot of places in the suspend
> > process and eventually an unintentional keystroke (or mouse movement,
> > when it comes to the Hyper-V mouse driver drivers/hid/hid-hyperv.c)
> > causes the whole hibernation process to be aborted. Usually this
> > behavior is not expected by the user, I think.
>
> Why not? If a device is configured as wakeup source, then it activity
> should wake up the system, unless you disable it.
Generally speaking, I agree, but compared to a physical machine, IMO
the scenario is a little differnet when it comes to a VM running on Hyper-V:
on the host there is a window that represents the VM, and the user can
unintentionally switch the keyboard input focus to the window (or move
the mouse/cursor over the window) and then the host automatically
sends some special keystrokes (and mouse events) , and this aborts the
hibernation process.
And, when it comes to the Hyper-V mouse device, IMO it's easy for the
user to unintentionally move the mouse after the "hibernation" button
is clicked. I suppose a physical machine would have the same issue, though.
> > So, I use the notifier to set the flag variable and with it the driver can
> > know when it should not call pm_wakeup_hard_event().
>
> No, please implement hibernation support properly, as notifier + flag is
> a hack.
The keyboard/mouse driver can avoid the flag by disabling the
keyboard/mouse event handling, but the problem is that they don't know
when exactly they should disable the event handling. I think the PM
notifier is the only way to tell the drivers a hibernation process is ongoing.
Do you think this idea (notifer + disabling event handling) is acceptable?
If not, then I'll have to remove the notifer completely, and document this as
a known issue to the user: when a hibernation process is started, be careful
to not switch input focus and not touch the keyboard/mouse until the
hibernation process is finished. :-)
> In this particular case you do not want to have your
> hv_kbd_resume() to be called in place of pm_ops->thaw() as that is what
> reenables the keyboard vmbus channel and causes the undesired wakeup
> events.
This is only part of the issues. Another example: before the
pm_ops()->freeze()'s of all the devices are called, pm_wakeup_pending()
is already tested in a lot of places (e.g. in try_to_freeze_tasks ()) in the
suspend process, and can abort the whole suspend process upon the user's
unintentional input focus switch, keystroke and mouse movement.
> Your vmbus implementation should allow individual drivers to
> control the set of PM operations that they wish to use, instead of
> forcing everything through suspend/resume.
>
> Dmitry
Since the devices are pure software-emulated devices, no PM operation was
supported in the past, and now suspend/resume are the only two PM operations
we're going to support. If the idea (notifer + disabling event handling) is not
good enough, we'll have to document the issue to the user, as I described above.
Thanks,
-- Dexuan
^ permalink raw reply
* Re: [PATCH] x86/hyperv: make vapic support x2apic mode
From: kbuild test robot @ 2019-09-30 22:44 UTC (permalink / raw)
To: Roman Kagan
Cc: kbuild-all, Michael Kelley, Lan Tianyu, Joerg Roedel,
K. Y. Srinivasan, Haiyang Zhang, Stephen Hemminger, Sasha Levin,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin,
x86@kernel.org, linux-hyperv@vger.kernel.org,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
In-Reply-To: <20190930173332.13655-1-rkagan@virtuozzo.com>
[-- Attachment #1: Type: text/plain, Size: 2817 bytes --]
Hi Roman,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on tip/x86/core]
[cannot apply to v5.4-rc1 next-20190930]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Roman-Kagan/x86-hyperv-make-vapic-support-x2apic-mode/20191001-044238
config: x86_64-randconfig-e004-201939 (attached as .config)
compiler: gcc-7 (Debian 7.4.0-13) 7.4.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
arch/x86/hyperv/hv_apic.c: In function 'hv_x2apic_read':
>> arch/x86/hyperv/hv_apic.c:91:10: error: implicit declaration of function 'native_apic_msr_read'; did you mean 'native_apic_icr_read'? [-Werror=implicit-function-declaration]
return native_apic_msr_read(reg);
^~~~~~~~~~~~~~~~~~~~
native_apic_icr_read
arch/x86/hyperv/hv_apic.c: In function 'hv_x2apic_write':
>> arch/x86/hyperv/hv_apic.c:119:3: error: implicit declaration of function 'native_apic_msr_write'; did you mean 'native_apic_icr_write'? [-Werror=implicit-function-declaration]
native_apic_msr_write(reg, val);
^~~~~~~~~~~~~~~~~~~~~
native_apic_icr_write
cc1: some warnings being treated as errors
vim +91 arch/x86/hyperv/hv_apic.c
77
78 static u32 hv_x2apic_read(u32 reg)
79 {
80 u32 reg_val, hi;
81
82 switch (reg) {
83 case APIC_EOI:
84 rdmsr(HV_X64_MSR_EOI, reg_val, hi);
85 return reg_val;
86 case APIC_TASKPRI:
87 rdmsr(HV_X64_MSR_TPR, reg_val, hi);
88 return reg_val;
89
90 default:
> 91 return native_apic_msr_read(reg);
92 }
93 }
94
95 static void hv_apic_write(u32 reg, u32 val)
96 {
97 switch (reg) {
98 case APIC_EOI:
99 wrmsr(HV_X64_MSR_EOI, val, 0);
100 break;
101 case APIC_TASKPRI:
102 wrmsr(HV_X64_MSR_TPR, val, 0);
103 break;
104 default:
105 native_apic_mem_write(reg, val);
106 }
107 }
108
109 static void hv_x2apic_write(u32 reg, u32 val)
110 {
111 switch (reg) {
112 case APIC_EOI:
113 wrmsr(HV_X64_MSR_EOI, val, 0);
114 break;
115 case APIC_TASKPRI:
116 wrmsr(HV_X64_MSR_TPR, val, 0);
117 break;
118 default:
> 119 native_apic_msr_write(reg, val);
120 }
121 }
122
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 31452 bytes --]
^ permalink raw reply
* Re: [PATCH] x86/hyperv: make vapic support x2apic mode
From: kbuild test robot @ 2019-09-30 23:04 UTC (permalink / raw)
To: Roman Kagan
Cc: kbuild-all, Michael Kelley, Lan Tianyu, Joerg Roedel,
K. Y. Srinivasan, Haiyang Zhang, Stephen Hemminger, Sasha Levin,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin,
x86@kernel.org, linux-hyperv@vger.kernel.org,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
In-Reply-To: <20190930173332.13655-1-rkagan@virtuozzo.com>
[-- Attachment #1: Type: text/plain, Size: 2681 bytes --]
Hi Roman,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on tip/x86/core]
[cannot apply to v5.4-rc1 next-20190930]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/Roman-Kagan/x86-hyperv-make-vapic-support-x2apic-mode/20191001-044238
config: x86_64-randconfig-s0-201939 (attached as .config)
compiler: gcc-5 (Ubuntu 5.5.0-12ubuntu1) 5.5.0 20171010
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
arch/x86//hyperv/hv_apic.c: In function 'hv_x2apic_read':
>> arch/x86//hyperv/hv_apic.c:91:10: error: implicit declaration of function 'native_apic_msr_read' [-Werror=implicit-function-declaration]
return native_apic_msr_read(reg);
^
arch/x86//hyperv/hv_apic.c: In function 'hv_x2apic_write':
>> arch/x86//hyperv/hv_apic.c:119:3: error: implicit declaration of function 'native_apic_msr_write' [-Werror=implicit-function-declaration]
native_apic_msr_write(reg, val);
^
cc1: some warnings being treated as errors
vim +/native_apic_msr_read +91 arch/x86//hyperv/hv_apic.c
77
78 static u32 hv_x2apic_read(u32 reg)
79 {
80 u32 reg_val, hi;
81
82 switch (reg) {
83 case APIC_EOI:
84 rdmsr(HV_X64_MSR_EOI, reg_val, hi);
85 return reg_val;
86 case APIC_TASKPRI:
87 rdmsr(HV_X64_MSR_TPR, reg_val, hi);
88 return reg_val;
89
90 default:
> 91 return native_apic_msr_read(reg);
92 }
93 }
94
95 static void hv_apic_write(u32 reg, u32 val)
96 {
97 switch (reg) {
98 case APIC_EOI:
99 wrmsr(HV_X64_MSR_EOI, val, 0);
100 break;
101 case APIC_TASKPRI:
102 wrmsr(HV_X64_MSR_TPR, val, 0);
103 break;
104 default:
105 native_apic_mem_write(reg, val);
106 }
107 }
108
109 static void hv_x2apic_write(u32 reg, u32 val)
110 {
111 switch (reg) {
112 case APIC_EOI:
113 wrmsr(HV_X64_MSR_EOI, val, 0);
114 break;
115 case APIC_TASKPRI:
116 wrmsr(HV_X64_MSR_TPR, val, 0);
117 break;
118 default:
> 119 native_apic_msr_write(reg, val);
120 }
121 }
122
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 30710 bytes --]
^ permalink raw reply
* Re: [PATCH] Input: hyperv-keyboard: Add the support of hibernation
From: dmitry.torokhov @ 2019-09-30 23:06 UTC (permalink / raw)
To: Dexuan Cui
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
sashal@kernel.org, linux-hyperv@vger.kernel.org,
linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley
In-Reply-To: <PU1P153MB0169C315F7F9EBEBED4C7A7DBF820@PU1P153MB0169.APCP153.PROD.OUTLOOK.COM>
On Mon, Sep 30, 2019 at 10:09:27PM +0000, Dexuan Cui wrote:
> > From: dmitry.torokhov@gmail.com <dmitry.torokhov@gmail.com>
> > Sent: Friday, September 27, 2019 5:32 PM
> > > ...
> > > pm_wakeup_pending() is tested in a lot of places in the suspend
> > > process and eventually an unintentional keystroke (or mouse movement,
> > > when it comes to the Hyper-V mouse driver drivers/hid/hid-hyperv.c)
> > > causes the whole hibernation process to be aborted. Usually this
> > > behavior is not expected by the user, I think.
> >
> > Why not? If a device is configured as wakeup source, then it activity
> > should wake up the system, unless you disable it.
>
> Generally speaking, I agree, but compared to a physical machine, IMO
> the scenario is a little differnet when it comes to a VM running on Hyper-V:
> on the host there is a window that represents the VM, and the user can
> unintentionally switch the keyboard input focus to the window (or move
> the mouse/cursor over the window) and then the host automatically
> sends some special keystrokes (and mouse events) , and this aborts the
> hibernation process.
>
> And, when it comes to the Hyper-V mouse device, IMO it's easy for the
> user to unintentionally move the mouse after the "hibernation" button
> is clicked. I suppose a physical machine would have the same issue, though.
If waking the machine up by mouse/keyboard activity is not desired in
Hyper-V environment, then simply disable them as wakeup sources.
>
> > > So, I use the notifier to set the flag variable and with it the driver can
> > > know when it should not call pm_wakeup_hard_event().
> >
> > No, please implement hibernation support properly, as notifier + flag is
> > a hack.
>
> The keyboard/mouse driver can avoid the flag by disabling the
> keyboard/mouse event handling, but the problem is that they don't know
> when exactly they should disable the event handling. I think the PM
> notifier is the only way to tell the drivers a hibernation process is ongoing.
Whatever initiates hibernation (in userspace) can adjust wakeup sources
as needed if you want them disabled completely.
>
> Do you think this idea (notifer + disabling event handling) is acceptable?
No, I believe this a hack, that is why I am pushing back on this.
>
> If not, then I'll have to remove the notifer completely, and document this as
> a known issue to the user: when a hibernation process is started, be careful
> to not switch input focus and not touch the keyboard/mouse until the
> hibernation process is finished. :-)
>
> > In this particular case you do not want to have your
> > hv_kbd_resume() to be called in place of pm_ops->thaw() as that is what
> > reenables the keyboard vmbus channel and causes the undesired wakeup
> > events.
>
> This is only part of the issues. Another example: before the
> pm_ops()->freeze()'s of all the devices are called, pm_wakeup_pending()
> is already tested in a lot of places (e.g. in try_to_freeze_tasks ()) in the
> suspend process, and can abort the whole suspend process upon the user's
> unintentional input focus switch, keystroke and mouse movement.
How long is the prepare() phase on your systems? User may wiggle mouse
at any time really, even before the notifier fires up.
>
> > Your vmbus implementation should allow individual drivers to
> > control the set of PM operations that they wish to use, instead of
> > forcing everything through suspend/resume.
> >
> > Dmitry
>
> Since the devices are pure software-emulated devices, no PM operation was
> supported in the past, and now suspend/resume are the only two PM operations
> we're going to support. If the idea (notifer + disabling event handling) is not
> good enough, we'll have to document the issue to the user, as I described above.
¯\_(ツ)_/¯ If you do not want to implement hibernation properly in vmbus
code that is totally up to you (have you read in pm.h how freeze() is
different from suspend()?).
Thanks.
--
Dmitry
^ permalink raw reply
* Re: [PATCH net v3] vsock: Fix a lockdep warning in __vsock_release()
From: Stefano Garzarella @ 2019-10-01 7:28 UTC (permalink / raw)
To: Dexuan Cui
Cc: davem@davemloft.net, KY Srinivasan, Haiyang Zhang,
Stephen Hemminger, sashal@kernel.org, stefanha@redhat.com,
gregkh@linuxfoundation.org, arnd@arndb.de, deepa.kernel@gmail.com,
ytht.net@gmail.com, tglx@linutronix.de, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org,
kvm@vger.kernel.org, virtualization@lists.linux-foundation.org,
Michael Kelley, jhansen@vmware.com
In-Reply-To: <1569868998-56603-1-git-send-email-decui@microsoft.com>
On Mon, Sep 30, 2019 at 06:43:50PM +0000, Dexuan Cui wrote:
> Lockdep is unhappy if two locks from the same class are held.
>
> Fix the below warning for hyperv and virtio sockets (vmci socket code
> doesn't have the issue) by using lock_sock_nested() when __vsock_release()
> is called recursively:
>
> ============================================
> WARNING: possible recursive locking detected
> 5.3.0+ #1 Not tainted
> --------------------------------------------
> server/1795 is trying to acquire lock:
> ffff8880c5158990 (sk_lock-AF_VSOCK){+.+.}, at: hvs_release+0x10/0x120 [hv_sock]
>
> but task is already holding lock:
> ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]
>
> other info that might help us debug this:
> Possible unsafe locking scenario:
>
> CPU0
> ----
> lock(sk_lock-AF_VSOCK);
> lock(sk_lock-AF_VSOCK);
>
> *** DEADLOCK ***
>
> May be due to missing lock nesting notation
>
> 2 locks held by server/1795:
> #0: ffff8880c5d05ff8 (&sb->s_type->i_mutex_key#10){+.+.}, at: __sock_release+0x2d/0xa0
> #1: ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]
>
> stack backtrace:
> CPU: 5 PID: 1795 Comm: server Not tainted 5.3.0+ #1
> Call Trace:
> dump_stack+0x67/0x90
> __lock_acquire.cold.67+0xd2/0x20b
> lock_acquire+0xb5/0x1c0
> lock_sock_nested+0x6d/0x90
> hvs_release+0x10/0x120 [hv_sock]
> __vsock_release+0x24/0xf0 [vsock]
> __vsock_release+0xa0/0xf0 [vsock]
> vsock_release+0x12/0x30 [vsock]
> __sock_release+0x37/0xa0
> sock_close+0x14/0x20
> __fput+0xc1/0x250
> task_work_run+0x98/0xc0
> do_exit+0x344/0xc60
> do_group_exit+0x47/0xb0
> get_signal+0x15c/0xc50
> do_signal+0x30/0x720
> exit_to_usermode_loop+0x50/0xa0
> do_syscall_64+0x24e/0x270
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x7f4184e85f31
>
> Tested-by: Stefano Garzarella <sgarzare@redhat.com>
> Signed-off-by: Dexuan Cui <decui@microsoft.com>
> ---
The patch LGTM and and functionally it's the same as the v2 that I tested, so:
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Thanks,
Stefano
>
> Changes in v2:
> Avoid the duplication of code in v1.
> Also fix virtio socket code.
>
>
> Changes in v3:
> Use "lock_sock_nested(sk, level);" -- suggested by Stefano.
> Add Stefano's Tested-by.
>
> net/vmw_vsock/af_vsock.c | 16 ++++++++++++----
> net/vmw_vsock/hyperv_transport.c | 2 +-
> net/vmw_vsock/virtio_transport_common.c | 2 +-
> 3 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> index ab47bf3ab66e..2ab43b2bba31 100644
> --- a/net/vmw_vsock/af_vsock.c
> +++ b/net/vmw_vsock/af_vsock.c
> @@ -638,7 +638,7 @@ struct sock *__vsock_create(struct net *net,
> }
> EXPORT_SYMBOL_GPL(__vsock_create);
>
> -static void __vsock_release(struct sock *sk)
> +static void __vsock_release(struct sock *sk, int level)
> {
> if (sk) {
> struct sk_buff *skb;
> @@ -648,9 +648,17 @@ static void __vsock_release(struct sock *sk)
> vsk = vsock_sk(sk);
> pending = NULL; /* Compiler warning. */
>
> + /* The release call is supposed to use lock_sock_nested()
> + * rather than lock_sock(), if a sock lock should be acquired.
> + */
> transport->release(vsk);
>
> - lock_sock(sk);
> + /* When "level" is SINGLE_DEPTH_NESTING, use the nested
> + * version to avoid the warning "possible recursive locking
> + * detected". When "level" is 0, lock_sock_nested(sk, level)
> + * is the same as lock_sock(sk).
> + */
> + lock_sock_nested(sk, level);
> sock_orphan(sk);
> sk->sk_shutdown = SHUTDOWN_MASK;
>
> @@ -659,7 +667,7 @@ static void __vsock_release(struct sock *sk)
>
> /* Clean up any sockets that never were accepted. */
> while ((pending = vsock_dequeue_accept(sk)) != NULL) {
> - __vsock_release(pending);
> + __vsock_release(pending, SINGLE_DEPTH_NESTING);
> sock_put(pending);
> }
>
> @@ -708,7 +716,7 @@ EXPORT_SYMBOL_GPL(vsock_stream_has_space);
>
> static int vsock_release(struct socket *sock)
> {
> - __vsock_release(sock->sk);
> + __vsock_release(sock->sk, 0);
> sock->sk = NULL;
> sock->state = SS_FREE;
>
> diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
> index 261521d286d6..c443db7af8d4 100644
> --- a/net/vmw_vsock/hyperv_transport.c
> +++ b/net/vmw_vsock/hyperv_transport.c
> @@ -559,7 +559,7 @@ static void hvs_release(struct vsock_sock *vsk)
> struct sock *sk = sk_vsock(vsk);
> bool remove_sock;
>
> - lock_sock(sk);
> + lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
> remove_sock = hvs_close_lock_held(vsk);
> release_sock(sk);
> if (remove_sock)
> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> index 5bb70c692b1e..a666ef8fc54e 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -820,7 +820,7 @@ void virtio_transport_release(struct vsock_sock *vsk)
> struct sock *sk = &vsk->sk;
> bool remove_sock = true;
>
> - lock_sock(sk);
> + lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
> if (sk->sk_type == SOCK_STREAM)
> remove_sock = virtio_transport_close(vsk);
>
> --
> 2.19.1
>
--
^ permalink raw reply
* Re: [PATCH] x86/hyperv: make vapic support x2apic mode
From: Roman Kagan @ 2019-10-01 9:18 UTC (permalink / raw)
To: kbuild test robot
Cc: kbuild-all@01.org, Michael Kelley, Lan Tianyu, Joerg Roedel,
K. Y. Srinivasan, Haiyang Zhang, Stephen Hemminger, Sasha Levin,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin,
x86@kernel.org, linux-hyperv@vger.kernel.org,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
In-Reply-To: <201910010607.cwCYMTaB%lkp@intel.com>
On Tue, Oct 01, 2019 at 06:44:08AM +0800, kbuild test robot wrote:
> url: https://github.com/0day-ci/linux/commits/Roman-Kagan/x86-hyperv-make-vapic-support-x2apic-mode/20191001-044238
> config: x86_64-randconfig-e004-201939 (attached as .config)
> compiler: gcc-7 (Debian 7.4.0-13) 7.4.0
> reproduce:
> # save the attached .config to linux build tree
> make ARCH=x86_64
>
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@intel.com>
>
> All errors (new ones prefixed by >>):
>
> arch/x86/hyperv/hv_apic.c: In function 'hv_x2apic_read':
> >> arch/x86/hyperv/hv_apic.c:91:10: error: implicit declaration of function 'native_apic_msr_read'; did you mean 'native_apic_icr_read'? [-Werror=implicit-function-declaration]
> return native_apic_msr_read(reg);
> ^~~~~~~~~~~~~~~~~~~~
> native_apic_icr_read
> arch/x86/hyperv/hv_apic.c: In function 'hv_x2apic_write':
> >> arch/x86/hyperv/hv_apic.c:119:3: error: implicit declaration of function 'native_apic_msr_write'; did you mean 'native_apic_icr_write'? [-Werror=implicit-function-declaration]
> native_apic_msr_write(reg, val);
> ^~~~~~~~~~~~~~~~~~~~~
> native_apic_icr_write
> cc1: some warnings being treated as errors
Oops, !CONFIG_X86_X2APIC needs to be handled. Will post v2.
Roman.
^ permalink raw reply
* [PATCH v2 0/3] Add a unified parameter "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:08 UTC (permalink / raw)
To: linux-kernel; +Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan
There are cases folks want to disable spinlock optimization for
debug/test purpose. Xen and hyperv already have parameters "xen_nopvspin"
and "hv_nopvspin" to support that, but kvm doesn't.
The first patch adds that feature to KVM guest with "nopvspin".
For compatibility reason original parameters "xen_nopvspin" and
"hv_nopvspin" are retained and marked obsolete.
v2:
PATCH1: pick the print code change into seperate PATCH2,
updated patch description [Vitaly Kuznetsov]
PATCH2: new patch with print code change [Vitaly Kuznetsov]
PATCH3: add Reviewed-by [Juergen Gross]
Thanks
Zhenzhong
^ permalink raw reply
* [PATCH v2 4/4] x86/hyperv: Mark "hv_nopvspin" parameter obsolete and map it to "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:09 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
K. Y. Srinivasan, Haiyang Zhang, Stephen Hemminger, Sasha Levin,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin
In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com>
Includes asm/hypervisor.h in order to reference x86_hyper_type.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
Documentation/admin-guide/kernel-parameters.txt | 6 +++++-
arch/x86/hyperv/hv_spinlock.c | 9 +++++----
2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1f0a62f..43f922c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1436,6 +1436,10 @@
hv_nopvspin [X86,HYPER_V] Disables the paravirt spinlock optimizations
which allow the hypervisor to 'idle' the
guest on lock contention.
+ This parameter is obsoleted by "nopvspin"
+ parameter, which has equivalent effect for
+ HYPER_V platform.
+
keep_bootcon [KNL]
Do not unregister boot console at start. This is only
@@ -5331,7 +5335,7 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
- nopvspin [X86,XEN,KVM] Disables the qspinlock slow path
+ nopvspin [X86,XEN,KVM,HYPER_V] Disables the qspinlock slow path
using PV optimizations which allow the hypervisor to
'idle' the guest on lock contention.
diff --git a/arch/x86/hyperv/hv_spinlock.c b/arch/x86/hyperv/hv_spinlock.c
index 07f21a0..e00e319 100644
--- a/arch/x86/hyperv/hv_spinlock.c
+++ b/arch/x86/hyperv/hv_spinlock.c
@@ -12,12 +12,11 @@
#include <linux/spinlock.h>
+#include <asm/hypervisor.h>
#include <asm/mshyperv.h>
#include <asm/paravirt.h>
#include <asm/apic.h>
-static bool __initdata hv_pvspin = true;
-
static void hv_qlock_kick(int cpu)
{
apic->send_IPI(cpu, X86_PLATFORM_IPI_VECTOR);
@@ -64,7 +63,7 @@ __visible bool hv_vcpu_is_preempted(int vcpu)
void __init hv_init_spinlocks(void)
{
- if (!hv_pvspin || !apic ||
+ if (!pvspin || !apic ||
!(ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) ||
!(ms_hyperv.features & HV_X64_MSR_GUEST_IDLE_AVAILABLE)) {
pr_info("PV spinlocks disabled\n");
@@ -82,7 +81,9 @@ void __init hv_init_spinlocks(void)
static __init int hv_parse_nopvspin(char *arg)
{
- hv_pvspin = false;
+ pr_notice("\"hv_nopvspin\" is deprecated, please use \"nopvspin\" instead\n");
+ if (x86_hyper_type == X86_HYPER_MS_HYPERV)
+ pvspin = false;
return 0;
}
early_param("hv_nopvspin", hv_parse_nopvspin);
--
1.8.3.1
^ permalink raw reply related
* [PATCH v2 3/4] xen: Mark "xen_nopvspin" parameter obsolete and map it to "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:08 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
Boris Ostrovsky, Juergen Gross, Stefano Stabellini,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin
In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com>
Fix stale description of "xen_nopvspin" as we use qspinlock now.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
Documentation/admin-guide/kernel-parameters.txt | 7 ++++---
arch/x86/xen/spinlock.c | 13 +++++++------
2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4b956d8..1f0a62f 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5303,8 +5303,9 @@
never -- do not unplug even if version check succeeds
xen_nopvspin [X86,XEN]
- Disables the ticketlock slowpath using Xen PV
- optimizations.
+ Disables the qspinlock slowpath using Xen PV optimizations.
+ This parameter is obsoleted by "nopvspin" parameter, which
+ has equivalent effect for XEN platform.
xen_nopv [X86]
Disables the PV optimizations forcing the HVM guest to
@@ -5330,7 +5331,7 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
- nopvspin [X86,KVM] Disables the qspinlock slow path
+ nopvspin [X86,XEN,KVM] Disables the qspinlock slow path
using PV optimizations which allow the hypervisor to
'idle' the guest on lock contention.
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 6deb490..092a53f 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -18,7 +18,6 @@
static DEFINE_PER_CPU(int, lock_kicker_irq) = -1;
static DEFINE_PER_CPU(char *, irq_name);
static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest);
-static bool xen_pvspin = true;
static void xen_qlock_kick(int cpu)
{
@@ -68,7 +67,7 @@ void xen_init_lock_cpu(int cpu)
int irq;
char *name;
- if (!xen_pvspin)
+ if (!pvspin)
return;
WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
@@ -93,7 +92,7 @@ void xen_init_lock_cpu(int cpu)
void xen_uninit_lock_cpu(int cpu)
{
- if (!xen_pvspin)
+ if (!pvspin)
return;
unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL);
@@ -117,9 +116,9 @@ void __init xen_init_spinlocks(void)
/* Don't need to use pvqspinlock code if there is only 1 vCPU. */
if (num_possible_cpus() == 1)
- xen_pvspin = false;
+ pvspin = false;
- if (!xen_pvspin) {
+ if (!pvspin) {
printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
static_branch_disable(&virt_spin_lock_key);
return;
@@ -137,7 +136,9 @@ void __init xen_init_spinlocks(void)
static __init int xen_parse_nopvspin(char *arg)
{
- xen_pvspin = false;
+ pr_notice("\"xen_nopvspin\" is deprecated, please use \"nopvspin\" instead\n");
+ if (xen_domain())
+ pvspin = false;
return 0;
}
early_param("xen_nopvspin", xen_parse_nopvspin);
--
1.8.3.1
^ permalink raw reply related
* [PATCH v2 2/4] x86/kvm: Change print code to use pr_*() format
From: Zhenzhong Duan @ 2019-09-30 12:08 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Paolo Bonzini,
Radim Krcmar, Sean Christopherson, Wanpeng Li, Jim Mattson,
Joerg Roedel, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
H. Peter Anvin
In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com>
pr_*() is preferred than printk(KERN_* ...), after change all the print
in arch/x86/kernel/kvm.c will have "KVM: xxx" style.
No functional change.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
arch/x86/kernel/kvm.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index a4f108d..7b8cf0d 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -7,6 +7,8 @@
* Authors: Anthony Liguori <aliguori@us.ibm.com>
*/
+#define pr_fmt(fmt) "KVM: " fmt
+
#include <linux/context_tracking.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -286,7 +288,7 @@ static void kvm_register_steal_time(void)
return;
wrmsrl(MSR_KVM_STEAL_TIME, (slow_virt_to_phys(st) | KVM_MSR_ENABLED));
- pr_info("kvm-stealtime: cpu %d, msr %llx\n",
+ pr_info("stealtime: cpu %d, msr %llx\n",
cpu, (unsigned long long) slow_virt_to_phys(st));
}
@@ -321,7 +323,7 @@ static void kvm_guest_cpu_init(void)
wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);
__this_cpu_write(apf_reason.enabled, 1);
- printk(KERN_INFO"KVM setup async PF for cpu %d\n",
+ pr_info("setup async PF for cpu %d\n",
smp_processor_id());
}
@@ -347,7 +349,7 @@ static void kvm_pv_disable_apf(void)
wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
__this_cpu_write(apf_reason.enabled, 0);
- printk(KERN_INFO"Unregister pv shared memory for cpu %d\n",
+ pr_info("Unregister pv shared memory for cpu %d\n",
smp_processor_id());
}
@@ -509,7 +511,7 @@ static void kvm_setup_pv_ipi(void)
{
apic->send_IPI_mask = kvm_send_ipi_mask;
apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
- pr_info("KVM setup pv IPIs\n");
+ pr_info("setup pv IPIs\n");
}
static void kvm_smp_send_call_func_ipi(const struct cpumask *mask)
@@ -639,11 +641,11 @@ static void __init kvm_guest_init(void)
!kvm_para_has_hint(KVM_HINTS_REALTIME) &&
kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) {
smp_ops.send_call_func_ipi = kvm_smp_send_call_func_ipi;
- pr_info("KVM setup pv sched yield\n");
+ pr_info("setup pv sched yield\n");
}
if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/kvm:online",
kvm_cpu_online, kvm_cpu_down_prepare) < 0)
- pr_err("kvm_guest: Failed to install cpu hotplug callbacks\n");
+ pr_err("failed to install cpu hotplug callbacks\n");
#else
sev_map_percpu_data();
kvm_guest_cpu_init();
@@ -746,7 +748,7 @@ static __init int kvm_setup_pv_tlb_flush(void)
zalloc_cpumask_var_node(per_cpu_ptr(&__pv_tlb_mask, cpu),
GFP_KERNEL, cpu_to_node(cpu));
}
- pr_info("KVM setup pv remote TLB flush\n");
+ pr_info("setup pv remote TLB flush\n");
}
return 0;
@@ -879,8 +881,8 @@ static void kvm_enable_host_haltpoll(void *i)
void arch_haltpoll_enable(unsigned int cpu)
{
if (!kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) {
- pr_err_once("kvm: host does not support poll control\n");
- pr_err_once("kvm: host upgrade recommended\n");
+ pr_err_once("host does not support poll control\n");
+ pr_err_once("host upgrade recommended\n");
return;
}
--
1.8.3.1
^ permalink raw reply related
* [PATCH v2 1/4] x86/kvm: Add "nopvspin" parameter to disable PV spinlocks
From: Zhenzhong Duan @ 2019-09-30 12:08 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin,
Paolo Bonzini, Radim Krcmar, Sean Christopherson, Wanpeng Li,
Jim Mattson, Joerg Roedel, Peter Zijlstra, Will Deacon
In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com>
There are cases where a guest tries to switch spinlocks to bare metal
behavior (e.g. by setting "xen_nopvspin" on XEN platform and
"hv_nopvspin" on HYPER_V).
That feature is missed on KVM, add a new parameter "nopvspin" to disable
PV spinlocks for KVM guest.
This new parameter is also used to replace "xen_nopvspin" and
"hv_nopvspin".
The global variable pvspin isn't defined as __initdata as it's used at
runtime by XEN guest.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
---
Documentation/admin-guide/kernel-parameters.txt | 4 ++++
arch/x86/include/asm/qspinlock.h | 1 +
arch/x86/kernel/kvm.c | 7 +++++++
kernel/locking/qspinlock.c | 7 +++++++
4 files changed, 19 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index c7ac2f3..4b956d8 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5330,6 +5330,10 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
+ nopvspin [X86,KVM] Disables the qspinlock slow path
+ using PV optimizations which allow the hypervisor to
+ 'idle' the guest on lock contention.
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h
index 444d6fd..34a4484 100644
--- a/arch/x86/include/asm/qspinlock.h
+++ b/arch/x86/include/asm/qspinlock.h
@@ -32,6 +32,7 @@ static __always_inline u32 queued_fetch_set_pending_acquire(struct qspinlock *lo
extern void __pv_init_lock_hash(void);
extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
extern void __raw_callee_save___pv_queued_spin_unlock(struct qspinlock *lock);
+extern bool pvspin;
#define queued_spin_unlock queued_spin_unlock
/**
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index e820568..a4f108d 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -842,6 +842,13 @@ void __init kvm_spinlock_init(void)
if (num_possible_cpus() == 1)
return;
+ if (!pvspin) {
+ pr_info("PV spinlocks disabled\n");
+ static_branch_disable(&virt_spin_lock_key);
+ return;
+ }
+ pr_info("PV spinlocks enabled\n");
+
__pv_init_lock_hash();
pv_ops.lock.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath;
pv_ops.lock.queued_spin_unlock =
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index 2473f10..945b510 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -580,4 +580,11 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
#include "qspinlock_paravirt.h"
#include "qspinlock.c"
+bool pvspin = true;
+static __init int parse_nopvspin(char *arg)
+{
+ pvspin = false;
+ return 0;
+}
+early_param("nopvspin", parse_nopvspin);
#endif
--
1.8.3.1
^ permalink raw reply related
* Re: [PATCH v2 0/3] Add a unified parameter "nopvspin"
From: Zhenzhong Duan @ 2019-10-01 12:19 UTC (permalink / raw)
To: linux-kernel; +Cc: vkuznets, linux-hyperv, kvm
In-Reply-To: <1569845340-11884-1-git-send-email-zhenzhong.duan@oracle.com>
On 2019/9/30 20:08, Zhenzhong Duan wrote:
> There are cases folks want to disable spinlock optimization for
> debug/test purpose. Xen and hyperv already have parameters "xen_nopvspin"
> and "hv_nopvspin" to support that, but kvm doesn't.
>
> The first patch adds that feature to KVM guest with "nopvspin".
>
> For compatibility reason original parameters "xen_nopvspin" and
> "hv_nopvspin" are retained and marked obsolete.
>
> v2:
> PATCH1: pick the print code change into seperate PATCH2,
> updated patch description [Vitaly Kuznetsov]
> PATCH2: new patch with print code change [Vitaly Kuznetsov]
Sorry, please ignore this mail thread, just found the indentation in
PATCH2 is wrong. I'll send a v3 later.
Thanks
Zhenzhong
^ permalink raw reply
* [PATCH v3 0/4] Add a unified parameter "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:44 UTC (permalink / raw)
To: linux-kernel; +Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan
There are cases folks want to disable spinlock optimization for
debug/test purpose. Xen and hyperv already have parameters "xen_nopvspin"
and "hv_nopvspin" to support that, but kvm doesn't.
The first patch adds that feature to KVM guest with "nopvspin".
For compatibility reason original parameters "xen_nopvspin" and
"hv_nopvspin" are retained and marked obsolete.
v3:
PATCH2: Fix indentation
v2:
PATCH1: pick the print code change into separate PATCH2,
updated patch description [Vitaly Kuznetsov]
PATCH2: new patch with print code change [Vitaly Kuznetsov]
PATCH3: add Reviewed-by [Juergen Gross]
Thanks
Zhenzhong
^ permalink raw reply
* [PATCH v3 4/4] x86/hyperv: Mark "hv_nopvspin" parameter obsolete and map it to "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:44 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
K. Y. Srinivasan, Haiyang Zhang, Stephen Hemminger, Sasha Levin,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin
In-Reply-To: <1569847479-13201-1-git-send-email-zhenzhong.duan@oracle.com>
Includes asm/hypervisor.h in order to reference x86_hyper_type.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
Documentation/admin-guide/kernel-parameters.txt | 6 +++++-
arch/x86/hyperv/hv_spinlock.c | 9 +++++----
2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1f0a62f..43f922c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1436,6 +1436,10 @@
hv_nopvspin [X86,HYPER_V] Disables the paravirt spinlock optimizations
which allow the hypervisor to 'idle' the
guest on lock contention.
+ This parameter is obsoleted by "nopvspin"
+ parameter, which has equivalent effect for
+ HYPER_V platform.
+
keep_bootcon [KNL]
Do not unregister boot console at start. This is only
@@ -5331,7 +5335,7 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
- nopvspin [X86,XEN,KVM] Disables the qspinlock slow path
+ nopvspin [X86,XEN,KVM,HYPER_V] Disables the qspinlock slow path
using PV optimizations which allow the hypervisor to
'idle' the guest on lock contention.
diff --git a/arch/x86/hyperv/hv_spinlock.c b/arch/x86/hyperv/hv_spinlock.c
index 07f21a0..e00e319 100644
--- a/arch/x86/hyperv/hv_spinlock.c
+++ b/arch/x86/hyperv/hv_spinlock.c
@@ -12,12 +12,11 @@
#include <linux/spinlock.h>
+#include <asm/hypervisor.h>
#include <asm/mshyperv.h>
#include <asm/paravirt.h>
#include <asm/apic.h>
-static bool __initdata hv_pvspin = true;
-
static void hv_qlock_kick(int cpu)
{
apic->send_IPI(cpu, X86_PLATFORM_IPI_VECTOR);
@@ -64,7 +63,7 @@ __visible bool hv_vcpu_is_preempted(int vcpu)
void __init hv_init_spinlocks(void)
{
- if (!hv_pvspin || !apic ||
+ if (!pvspin || !apic ||
!(ms_hyperv.hints & HV_X64_CLUSTER_IPI_RECOMMENDED) ||
!(ms_hyperv.features & HV_X64_MSR_GUEST_IDLE_AVAILABLE)) {
pr_info("PV spinlocks disabled\n");
@@ -82,7 +81,9 @@ void __init hv_init_spinlocks(void)
static __init int hv_parse_nopvspin(char *arg)
{
- hv_pvspin = false;
+ pr_notice("\"hv_nopvspin\" is deprecated, please use \"nopvspin\" instead\n");
+ if (x86_hyper_type == X86_HYPER_MS_HYPERV)
+ pvspin = false;
return 0;
}
early_param("hv_nopvspin", hv_parse_nopvspin);
--
1.8.3.1
^ permalink raw reply related
* [PATCH v3 3/4] xen: Mark "xen_nopvspin" parameter obsolete and map it to "nopvspin"
From: Zhenzhong Duan @ 2019-09-30 12:44 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
Boris Ostrovsky, Juergen Gross, Stefano Stabellini,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin
In-Reply-To: <1569847479-13201-1-git-send-email-zhenzhong.duan@oracle.com>
Fix stale description of "xen_nopvspin" as we use qspinlock now.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
Documentation/admin-guide/kernel-parameters.txt | 7 ++++---
arch/x86/xen/spinlock.c | 13 +++++++------
2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4b956d8..1f0a62f 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5303,8 +5303,9 @@
never -- do not unplug even if version check succeeds
xen_nopvspin [X86,XEN]
- Disables the ticketlock slowpath using Xen PV
- optimizations.
+ Disables the qspinlock slowpath using Xen PV optimizations.
+ This parameter is obsoleted by "nopvspin" parameter, which
+ has equivalent effect for XEN platform.
xen_nopv [X86]
Disables the PV optimizations forcing the HVM guest to
@@ -5330,7 +5331,7 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
- nopvspin [X86,KVM] Disables the qspinlock slow path
+ nopvspin [X86,XEN,KVM] Disables the qspinlock slow path
using PV optimizations which allow the hypervisor to
'idle' the guest on lock contention.
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 6deb490..092a53f 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -18,7 +18,6 @@
static DEFINE_PER_CPU(int, lock_kicker_irq) = -1;
static DEFINE_PER_CPU(char *, irq_name);
static DEFINE_PER_CPU(atomic_t, xen_qlock_wait_nest);
-static bool xen_pvspin = true;
static void xen_qlock_kick(int cpu)
{
@@ -68,7 +67,7 @@ void xen_init_lock_cpu(int cpu)
int irq;
char *name;
- if (!xen_pvspin)
+ if (!pvspin)
return;
WARN(per_cpu(lock_kicker_irq, cpu) >= 0, "spinlock on CPU%d exists on IRQ%d!\n",
@@ -93,7 +92,7 @@ void xen_init_lock_cpu(int cpu)
void xen_uninit_lock_cpu(int cpu)
{
- if (!xen_pvspin)
+ if (!pvspin)
return;
unbind_from_irqhandler(per_cpu(lock_kicker_irq, cpu), NULL);
@@ -117,9 +116,9 @@ void __init xen_init_spinlocks(void)
/* Don't need to use pvqspinlock code if there is only 1 vCPU. */
if (num_possible_cpus() == 1)
- xen_pvspin = false;
+ pvspin = false;
- if (!xen_pvspin) {
+ if (!pvspin) {
printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
static_branch_disable(&virt_spin_lock_key);
return;
@@ -137,7 +136,9 @@ void __init xen_init_spinlocks(void)
static __init int xen_parse_nopvspin(char *arg)
{
- xen_pvspin = false;
+ pr_notice("\"xen_nopvspin\" is deprecated, please use \"nopvspin\" instead\n");
+ if (xen_domain())
+ pvspin = false;
return 0;
}
early_param("xen_nopvspin", xen_parse_nopvspin);
--
1.8.3.1
^ permalink raw reply related
* [PATCH v3 2/4] x86/kvm: Change print code to use pr_*() format
From: Zhenzhong Duan @ 2019-09-30 12:44 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Paolo Bonzini,
Radim Krcmar, Sean Christopherson, Wanpeng Li, Jim Mattson,
Joerg Roedel, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
H. Peter Anvin
In-Reply-To: <1569847479-13201-1-git-send-email-zhenzhong.duan@oracle.com>
pr_*() is preferred than printk(KERN_* ...), after change all the print
in arch/x86/kernel/kvm.c will have "KVM: xxx" style.
No functional change.
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
arch/x86/kernel/kvm.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index a4f108d..ce4f578 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -7,6 +7,8 @@
* Authors: Anthony Liguori <aliguori@us.ibm.com>
*/
+#define pr_fmt(fmt) "KVM: " fmt
+
#include <linux/context_tracking.h>
#include <linux/init.h>
#include <linux/kernel.h>
@@ -286,8 +288,8 @@ static void kvm_register_steal_time(void)
return;
wrmsrl(MSR_KVM_STEAL_TIME, (slow_virt_to_phys(st) | KVM_MSR_ENABLED));
- pr_info("kvm-stealtime: cpu %d, msr %llx\n",
- cpu, (unsigned long long) slow_virt_to_phys(st));
+ pr_info("stealtime: cpu %d, msr %llx\n", cpu,
+ (unsigned long long) slow_virt_to_phys(st));
}
static DEFINE_PER_CPU_DECRYPTED(unsigned long, kvm_apic_eoi) = KVM_PV_EOI_DISABLED;
@@ -321,8 +323,7 @@ static void kvm_guest_cpu_init(void)
wrmsrl(MSR_KVM_ASYNC_PF_EN, pa);
__this_cpu_write(apf_reason.enabled, 1);
- printk(KERN_INFO"KVM setup async PF for cpu %d\n",
- smp_processor_id());
+ pr_info("setup async PF for cpu %d\n", smp_processor_id());
}
if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
@@ -347,8 +348,7 @@ static void kvm_pv_disable_apf(void)
wrmsrl(MSR_KVM_ASYNC_PF_EN, 0);
__this_cpu_write(apf_reason.enabled, 0);
- printk(KERN_INFO"Unregister pv shared memory for cpu %d\n",
- smp_processor_id());
+ pr_info("Unregister pv shared memory for cpu %d\n", smp_processor_id());
}
static void kvm_pv_guest_cpu_reboot(void *unused)
@@ -509,7 +509,7 @@ static void kvm_setup_pv_ipi(void)
{
apic->send_IPI_mask = kvm_send_ipi_mask;
apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
- pr_info("KVM setup pv IPIs\n");
+ pr_info("setup pv IPIs\n");
}
static void kvm_smp_send_call_func_ipi(const struct cpumask *mask)
@@ -639,11 +639,11 @@ static void __init kvm_guest_init(void)
!kvm_para_has_hint(KVM_HINTS_REALTIME) &&
kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) {
smp_ops.send_call_func_ipi = kvm_smp_send_call_func_ipi;
- pr_info("KVM setup pv sched yield\n");
+ pr_info("setup pv sched yield\n");
}
if (cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/kvm:online",
kvm_cpu_online, kvm_cpu_down_prepare) < 0)
- pr_err("kvm_guest: Failed to install cpu hotplug callbacks\n");
+ pr_err("failed to install cpu hotplug callbacks\n");
#else
sev_map_percpu_data();
kvm_guest_cpu_init();
@@ -746,7 +746,7 @@ static __init int kvm_setup_pv_tlb_flush(void)
zalloc_cpumask_var_node(per_cpu_ptr(&__pv_tlb_mask, cpu),
GFP_KERNEL, cpu_to_node(cpu));
}
- pr_info("KVM setup pv remote TLB flush\n");
+ pr_info("setup pv remote TLB flush\n");
}
return 0;
@@ -879,8 +879,8 @@ static void kvm_enable_host_haltpoll(void *i)
void arch_haltpoll_enable(unsigned int cpu)
{
if (!kvm_para_has_feature(KVM_FEATURE_POLL_CONTROL)) {
- pr_err_once("kvm: host does not support poll control\n");
- pr_err_once("kvm: host upgrade recommended\n");
+ pr_err_once("host does not support poll control\n");
+ pr_err_once("host upgrade recommended\n");
return;
}
--
1.8.3.1
^ permalink raw reply related
* [PATCH v3 1/4] x86/kvm: Add "nopvspin" parameter to disable PV spinlocks
From: Zhenzhong Duan @ 2019-09-30 12:44 UTC (permalink / raw)
To: linux-kernel
Cc: vkuznets, linux-hyperv, kvm, Zhenzhong Duan, Jonathan Corbet,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, H. Peter Anvin,
Paolo Bonzini, Radim Krcmar, Sean Christopherson, Wanpeng Li,
Jim Mattson, Joerg Roedel, Peter Zijlstra, Will Deacon
In-Reply-To: <1569847479-13201-1-git-send-email-zhenzhong.duan@oracle.com>
There are cases where a guest tries to switch spinlocks to bare metal
behavior (e.g. by setting "xen_nopvspin" on XEN platform and
"hv_nopvspin" on HYPER_V).
That feature is missed on KVM, add a new parameter "nopvspin" to disable
PV spinlocks for KVM guest.
This new parameter is also used to replace "xen_nopvspin" and
"hv_nopvspin".
The global variable pvspin isn't defined as __initdata as it's used at
runtime by XEN guest.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
---
Documentation/admin-guide/kernel-parameters.txt | 4 ++++
arch/x86/include/asm/qspinlock.h | 1 +
arch/x86/kernel/kvm.c | 7 +++++++
kernel/locking/qspinlock.c | 7 +++++++
4 files changed, 19 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index c7ac2f3..4b956d8 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5330,6 +5330,10 @@
as generic guest with no PV drivers. Currently support
XEN HVM, KVM, HYPER_V and VMWARE guest.
+ nopvspin [X86,KVM] Disables the qspinlock slow path
+ using PV optimizations which allow the hypervisor to
+ 'idle' the guest on lock contention.
+
xirc2ps_cs= [NET,PCMCIA]
Format:
<irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h
index 444d6fd..34a4484 100644
--- a/arch/x86/include/asm/qspinlock.h
+++ b/arch/x86/include/asm/qspinlock.h
@@ -32,6 +32,7 @@ static __always_inline u32 queued_fetch_set_pending_acquire(struct qspinlock *lo
extern void __pv_init_lock_hash(void);
extern void __pv_queued_spin_lock_slowpath(struct qspinlock *lock, u32 val);
extern void __raw_callee_save___pv_queued_spin_unlock(struct qspinlock *lock);
+extern bool pvspin;
#define queued_spin_unlock queued_spin_unlock
/**
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index e820568..a4f108d 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -842,6 +842,13 @@ void __init kvm_spinlock_init(void)
if (num_possible_cpus() == 1)
return;
+ if (!pvspin) {
+ pr_info("PV spinlocks disabled\n");
+ static_branch_disable(&virt_spin_lock_key);
+ return;
+ }
+ pr_info("PV spinlocks enabled\n");
+
__pv_init_lock_hash();
pv_ops.lock.queued_spin_lock_slowpath = __pv_queued_spin_lock_slowpath;
pv_ops.lock.queued_spin_unlock =
diff --git a/kernel/locking/qspinlock.c b/kernel/locking/qspinlock.c
index 2473f10..945b510 100644
--- a/kernel/locking/qspinlock.c
+++ b/kernel/locking/qspinlock.c
@@ -580,4 +580,11 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
#include "qspinlock_paravirt.h"
#include "qspinlock.c"
+bool pvspin = true;
+static __init int parse_nopvspin(char *arg)
+{
+ pvspin = false;
+ return 0;
+}
+early_param("nopvspin", parse_nopvspin);
#endif
--
1.8.3.1
^ permalink raw reply related
* Re: [PATCH] video: hyperv_fb: Add the support of hibernation
From: Sasha Levin @ 2019-10-01 18:38 UTC (permalink / raw)
To: Dexuan Cui
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
b.zolnierkie@samsung.com, linux-hyperv@vger.kernel.org,
dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org, Michael Kelley
In-Reply-To: <1568244833-66476-1-git-send-email-decui@microsoft.com>
On Wed, Sep 11, 2019 at 11:34:10PM +0000, Dexuan Cui wrote:
>This patch depends on the vmbus side change of the definition of
>struct hv_driver.
>
>Signed-off-by: Dexuan Cui <decui@microsoft.com>
Queued up for hyperv-next, thanks!
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH] scsi: storvsc: Add the support of hibernation
From: Sasha Levin @ 2019-10-01 18:38 UTC (permalink / raw)
To: Martin K. Petersen
Cc: Dexuan Cui, KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
jejb@linux.ibm.com, linux-hyperv@vger.kernel.org,
linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley
In-Reply-To: <yq1zhj7byph.fsf@oracle.com>
On Fri, Sep 13, 2019 at 06:47:38PM -0400, Martin K. Petersen wrote:
>
>Dexuan,
>
>> When we're in storvsc_suspend(), we're sure the SCSI layer has
>> quiesced the scsi device by scsi_bus_suspend() -> ... ->
>> scsi_device_quiesce(), so the low level SCSI adapter driver only needs
>> to suspend/resume its own state.
>
>Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Queued up for hyperv-next, thanks!
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH] HID: hyperv: Add the support of hibernation
From: Sasha Levin @ 2019-10-01 18:40 UTC (permalink / raw)
To: Dexuan Cui
Cc: Jiri Kosina, KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
benjamin.tissoires@redhat.com, linux-hyperv@vger.kernel.org,
linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley
In-Reply-To: <PU1P153MB01698048162343130F34DAE0BF830@PU1P153MB0169.APCP153.PROD.OUTLOOK.COM>
On Sun, Sep 29, 2019 at 05:44:09PM +0000, Dexuan Cui wrote:
>> From: Sasha Levin <sashal@kernel.org>
>> Dexuan, I've been silently ignoring your patches for the past few weeks
>> for the same reason as Jiri has mentioned. I'll pick them all up once
>> the 5.4 merge window closes in a few days.
>
>Thanks, Sasha!
>
>BTW, I'll post a v2 for this patch, as IMO I may be able to get rid of the
>mousevsc_pm_notify in this patch by disabling the channel callback
>in the suspend function.
Okay, I'm ignoring this patch for now then.
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH v2] hv_sock: Add the support of hibernation
From: Sasha Levin @ 2019-10-01 18:42 UTC (permalink / raw)
To: Dexuan Cui
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
davem@davemloft.net, linux-hyperv@vger.kernel.org,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley
In-Reply-To: <1569447243-27433-1-git-send-email-decui@microsoft.com>
On Wed, Sep 25, 2019 at 09:34:13PM +0000, Dexuan Cui wrote:
>Add the necessary dummy callbacks for hibernation.
>
>Signed-off-by: Dexuan Cui <decui@microsoft.com>
>Acked-by: David S. Miller <davem@davemloft.net>
Queued up for hyperv-next, thanks!
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH v5] video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver
From: Sasha Levin @ 2019-10-01 18:45 UTC (permalink / raw)
To: Wei Hu
Cc: Michael Kelley, rdunlap@infradead.org, shc_work@mail.ru,
gregkh@linuxfoundation.org, lee.jones@linaro.org,
alexandre.belloni@bootlin.com, baijiaju1990@gmail.com,
fthain@telegraphics.com.au, info@metux.net,
linux-hyperv@vger.kernel.org, dri-devel@lists.freedesktop.org,
linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org,
Stephen Hemminger, Haiyang Zhang, KY Srinivasan, Dexuan Cui
In-Reply-To: <20190913060209.3604-1-weh@microsoft.com>
On Fri, Sep 13, 2019 at 06:02:55AM +0000, Wei Hu wrote:
>Without deferred IO support, hyperv_fb driver informs the host to refresh
>the entire guest frame buffer at fixed rate, e.g. at 20Hz, no matter there
>is screen update or not. This patch supports deferred IO for screens in
>graphics mode and also enables the frame buffer on-demand refresh. The
>highest refresh rate is still set at 20Hz.
>
>Currently Hyper-V only takes a physical address from guest as the starting
>address of frame buffer. This implies the guest must allocate contiguous
>physical memory for frame buffer. In addition, Hyper-V Gen 2 VMs only
>accept address from MMIO region as frame buffer address. Due to these
>limitations on Hyper-V host, we keep a shadow copy of frame buffer
>in the guest. This means one more copy of the dirty rectangle inside
>guest when doing the on-demand refresh. This can be optimized in the
>future with help from host. For now the host performance gain from deferred
>IO outweighs the shadow copy impact in the guest.
>
>Signed-off-by: Wei Hu <weh@microsoft.com>
What tree is this based on? I can't get it to apply.
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATHC v6] video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver
From: Sasha Levin @ 2019-10-01 18:48 UTC (permalink / raw)
To: Michael Kelley
Cc: Wei Hu, rdunlap@infradead.org, shc_work@mail.ru,
gregkh@linuxfoundation.org, lee.jones@linaro.org,
alexandre.belloni@bootlin.com, baijiaju1990@gmail.com,
info@metux.net, linux-hyperv@vger.kernel.org,
dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
linux-kernel@vger.kernel.org, Stephen Hemminger, Haiyang Zhang,
KY Srinivasan, Dexuan Cui
In-Reply-To: <DM5PR21MB01375E8543451D4550D622CDD7880@DM5PR21MB0137.namprd21.prod.outlook.com>
On Fri, Sep 20, 2019 at 05:26:34PM +0000, Michael Kelley wrote:
>From: Michael Kelley <mikelley@microsoft.com> Sent: Wednesday, September 18, 2019 2:48 PM
>> >
>> > Without deferred IO support, hyperv_fb driver informs the host to refresh
>> > the entire guest frame buffer at fixed rate, e.g. at 20Hz, no matter there
>> > is screen update or not. This patch supports deferred IO for screens in
>> > graphics mode and also enables the frame buffer on-demand refresh. The
>> > highest refresh rate is still set at 20Hz.
>> >
>> > Currently Hyper-V only takes a physical address from guest as the starting
>> > address of frame buffer. This implies the guest must allocate contiguous
>> > physical memory for frame buffer. In addition, Hyper-V Gen 2 VMs only
>> > accept address from MMIO region as frame buffer address. Due to these
>> > limitations on Hyper-V host, we keep a shadow copy of frame buffer
>> > in the guest. This means one more copy of the dirty rectangle inside
>> > guest when doing the on-demand refresh. This can be optimized in the
>> > future with help from host. For now the host performance gain from deferred
>> > IO outweighs the shadow copy impact in the guest.
>> >
>> > Signed-off-by: Wei Hu <weh@microsoft.com>
>
>Sasha -- this patch and one other from Wei Hu for the Hyper-V frame buffer
>driver should be ready. Both patches affect only the Hyper-V frame buffer
>driver so can go through the Hyper-V tree. Can you pick these up? Thx.
I can't get this to apply anywhere, what tree is it based on?
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH v3] Drivers: hv: vmbus: Fix harmless building warnings without CONFIG_PM_SLEEP
From: Sasha Levin @ 2019-10-01 18:50 UTC (permalink / raw)
To: Dexuan Cui
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Kelley, arnd@arndb.de
In-Reply-To: <1569436998-130708-1-git-send-email-decui@microsoft.com>
On Wed, Sep 25, 2019 at 06:43:57PM +0000, Dexuan Cui wrote:
>If CONFIG_PM_SLEEP is not set, we can comment out these functions to avoid
>the below warnings:
>
>drivers/hv/vmbus_drv.c:2208:12: warning: ‘vmbus_bus_resume’ defined but not used [-Wunused-function]
>drivers/hv/vmbus_drv.c:2128:12: warning: ‘vmbus_bus_suspend’ defined but not used [-Wunused-function]
>drivers/hv/vmbus_drv.c:937:12: warning: ‘vmbus_resume’ defined but not used [-Wunused-function]
>drivers/hv/vmbus_drv.c:918:12: warning: ‘vmbus_suspend’ defined but not used [-Wunused-function]
>
>Fixes: 271b2224d42f ("Drivers: hv: vmbus: Implement suspend/resume for VSC drivers for hibernation")
>Fixes: f53335e3289f ("Drivers: hv: vmbus: Suspend/resume the vmbus itself for hibernation")
>Reported-by: Arnd Bergmann <arnd@arndb.de>
>Reviewed-by: Michael Kelley <mikelley@microsoft.com>
>Signed-off-by: Dexuan Cui <decui@microsoft.com>
I've queued this up for hyperv-fixes.
>In v3:
> Add Michael's Reviewed-by.
> No other change.
There's really no need to re-spin just to add tags :)
--
Thanks,
Sasha
^ permalink raw reply
* Re: [PATCH v2] scsi: storvsc: Add the support of hibernation
From: Sasha Levin @ 2019-10-01 18:51 UTC (permalink / raw)
To: Dexuan Cui
Cc: KY Srinivasan, Haiyang Zhang, Stephen Hemminger,
jejb@linux.ibm.com, martin.petersen@oracle.com,
linux-hyperv@vger.kernel.org, linux-scsi@vger.kernel.org,
linux-kernel@vger.kernel.org, Michael Kelley
In-Reply-To: <1569442244-16726-1-git-send-email-decui@microsoft.com>
On Wed, Sep 25, 2019 at 08:11:08PM +0000, Dexuan Cui wrote:
>When we're in storvsc_suspend(), we're sure the SCSI layer has quiesced the
>scsi device by scsi_bus_suspend() -> ... -> scsi_device_quiesce(), so the
>low level SCSI adapter driver only needs to suspend/resume its own state.
>
>Signed-off-by: Dexuan Cui <decui@microsoft.com>
>Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
>
>---
>
>This patch is basically a pure Hyper-V specific change and it has a
>build dependency on the commit 271b2224d42f ("Drivers: hv: vmbus: Implement
>suspend/resume for VSC drivers for hibernation"), which is on Sasha Levin's
>Hyper-V tree's hyperv-next branch:
>https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git/log/?h=hyperv-next
>
>I request this patch should go through Sasha's tree rather than the
>SCSI tree.
>
>In v2:
> Added Acked-by from Martin.
>
> @Sasha: I think the patch can go through the hyper-v tree, since
> we have the Ack from Martin. :-)
Queued up for hyperv-next, thanks!
--
Thanks,
Sasha
^ permalink raw reply
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