xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Juergen Gross <jgross@suse.com>
To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org
Cc: jeremy@goop.org, jdelvare@suse.com, peterz@infradead.org,
	hpa@zytor.com, akataria@vmware.com, x86@kernel.org,
	rusty@rustcorp.com.au, virtualization@lists.linux-foundation.org,
	chrisw@sous-sol.org, mingo@redhat.com, david.vrabel@citrix.com,
	Douglas_Warzecha@dell.com, pali.rohar@gmail.com,
	boris.ostrovsky@oracle.com, tglx@linutronix.de,
	linux@roeck-us.net
Subject: Re: [PATCH v5 5/6] dcdbas: make use of smp_call_on_cpu()
Date: Wed, 15 Jun 2016 13:19:29 +0200	[thread overview]
Message-ID: <576139C1.4030301__46542.1262699694$1465989636$gmane$org@suse.com> (raw)
In-Reply-To: <1459952266-3687-6-git-send-email-jgross@suse.com>

On 06/04/16 16:17, Juergen Gross wrote:
> Use smp_call_on_cpu() to raise SMI on cpu 0.
> Make call secure by adding get_online_cpus() to avoid e.g. suspend
> resume cycles in between.
>
> Signed-off-by: Juergen Gross <jgross@suse.com>

Could please some maintainer comment on this patch?


Juergen

> ---
> V4: add call to get_online_cpus()
> ---
>   drivers/firmware/dcdbas.c | 51 ++++++++++++++++++++++++-----------------------
>   1 file changed, 26 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
> index 829eec8..2fe1a13 100644
> --- a/drivers/firmware/dcdbas.c
> +++ b/drivers/firmware/dcdbas.c
> @@ -23,6 +23,7 @@
>   #include <linux/platform_device.h>
>   #include <linux/dma-mapping.h>
>   #include <linux/errno.h>
> +#include <linux/cpu.h>
>   #include <linux/gfp.h>
>   #include <linux/init.h>
>   #include <linux/kernel.h>
> @@ -238,33 +239,14 @@ static ssize_t host_control_on_shutdown_store(struct device *dev,
>   	return count;
>   }
>
> -/**
> - * dcdbas_smi_request: generate SMI request
> - *
> - * Called with smi_data_lock.
> - */
> -int dcdbas_smi_request(struct smi_cmd *smi_cmd)
> +static int raise_smi(void *par)
>   {
> -	cpumask_var_t old_mask;
> -	int ret = 0;
> +	struct smi_cmd *smi_cmd = par;
>
> -	if (smi_cmd->magic != SMI_CMD_MAGIC) {
> -		dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
> -			 __func__);
> -		return -EBADR;
> -	}
> -
> -	/* SMI requires CPU 0 */
> -	if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
> -		return -ENOMEM;
> -
> -	cpumask_copy(old_mask, &current->cpus_allowed);
> -	set_cpus_allowed_ptr(current, cpumask_of(0));
>   	if (smp_processor_id() != 0) {
>   		dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
>   			__func__);
> -		ret = -EBUSY;
> -		goto out;
> +		return -EBUSY;
>   	}
>
>   	/* generate SMI */
> @@ -280,9 +262,28 @@ int dcdbas_smi_request(struct smi_cmd *smi_cmd)
>   		: "memory"
>   	);
>
> -out:
> -	set_cpus_allowed_ptr(current, old_mask);
> -	free_cpumask_var(old_mask);
> +	return 0;
> +}
> +/**
> + * dcdbas_smi_request: generate SMI request
> + *
> + * Called with smi_data_lock.
> + */
> +int dcdbas_smi_request(struct smi_cmd *smi_cmd)
> +{
> +	int ret;
> +
> +	if (smi_cmd->magic != SMI_CMD_MAGIC) {
> +		dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
> +			 __func__);
> +		return -EBADR;
> +	}
> +
> +	/* SMI requires CPU 0 */
> +	get_online_cpus();
> +	ret = smp_call_on_cpu(0, raise_smi, smi_cmd, true);
> +	put_online_cpus();
> +
>   	return ret;
>   }
>
>


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

  parent reply	other threads:[~2016-06-15 11:19 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1459952266-3687-1-git-send-email-jgross@suse.com>
2016-04-06 14:17 ` [PATCH v5 1/6] xen: sync xen header Juergen Gross
2016-04-06 14:17 ` [PATCH v5 2/6] virt, sched: add generic vcpu pinning support Juergen Gross
2016-04-06 14:17 ` [PATCH v5 3/6] smp: add function to execute a function synchronously on a cpu Juergen Gross
2016-04-06 14:17 ` [PATCH v5 4/6] xen: add xen_pin_vcpu() to support calling functions on a dedicated pcpu Juergen Gross
2016-04-06 14:17 ` [PATCH v5 5/6] dcdbas: make use of smp_call_on_cpu() Juergen Gross
2016-04-06 14:17 ` [PATCH v5 6/6] hwmon: use smp_call_on_cpu() for dell-smm i8k Juergen Gross
     [not found] ` <1459952266-3687-4-git-send-email-jgross@suse.com>
2016-04-06 18:04   ` [PATCH v5 3/6] smp: add function to execute a function synchronously on a cpu Peter Zijlstra
2016-04-13  8:49 ` [PATCH v5 0/6] Support calling functions on dedicated physical cpu Juergen Gross
     [not found] ` <570E07FD.4030403@suse.com>
2016-05-17 11:21   ` Juergen Gross
     [not found] ` <1459952266-3687-7-git-send-email-jgross@suse.com>
2016-06-13 19:05   ` [PATCH v5 6/6] hwmon: use smp_call_on_cpu() for dell-smm i8k Pali Rohár
     [not found] ` <1459952266-3687-3-git-send-email-jgross@suse.com>
2016-06-15 11:18   ` [PATCH v5 2/6] virt, sched: add generic vcpu pinning support Juergen Gross
     [not found] ` <1459952266-3687-6-git-send-email-jgross@suse.com>
2016-06-15 11:19   ` Juergen Gross [this message]
2016-06-20  8:40 ` [PATCH v5 0/6] Support calling functions on dedicated physical cpu Juergen Gross
2016-06-27 10:34 ` Juergen Gross

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='576139C1.4030301__46542.1262699694$1465989636$gmane$org@suse.com' \
    --to=jgross@suse.com \
    --cc=Douglas_Warzecha@dell.com \
    --cc=akataria@vmware.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=chrisw@sous-sol.org \
    --cc=david.vrabel@citrix.com \
    --cc=hpa@zytor.com \
    --cc=jdelvare@suse.com \
    --cc=jeremy@goop.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=mingo@redhat.com \
    --cc=pali.rohar@gmail.com \
    --cc=peterz@infradead.org \
    --cc=rusty@rustcorp.com.au \
    --cc=tglx@linutronix.de \
    --cc=virtualization@lists.linux-foundation.org \
    --cc=x86@kernel.org \
    --cc=xen-devel@lists.xenproject.org \
    --subject='Re: [PATCH v5 5/6] dcdbas: make use of smp_call_on_cpu()' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).