lkml.org 
[lkml]   [2020]   [Aug]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/2] s390: convert to GENERIC_VDSO
On Mon, Aug 03, 2020 at 06:05:24PM +0200, Thomas Gleixner wrote:
> +/**
> + * vdso_update_begin - Start of a VDSO update section
> + *
> + * Allows architecture code to safely update the architecture specific VDSO
> + * data.
> + */
> +void vdso_update_begin(void)
> +{
> + struct vdso_data *vdata = __arch_get_k_vdso_data();
> +
> + raw_spin_lock(&timekeeper_lock);
> + vdso_write_begin(vdata);
> +}

I would assume that this only works if vdso_update_begin() is called
with irqs disabled, otherwise it could deadlock, no?

Maybe something like:

void vdso_update_begin(unsigned long *flags)
{
struct vdso_data *vdata = __arch_get_k_vdso_data();

raw_spin_lock_irqsave(&timekeeper_lock, *flags);
vdso_write_begin(vdata);
}

void vdso_update_end(unsigned long *flags)
{
struct vdso_data *vdata = __arch_get_k_vdso_data();

vdso_write_end(vdata);
__arch_sync_vdso_data(vdata);
raw_spin_unlock_irqrestore(&timekeeper_lock, *flags);
}

? Just wondering.

\
 
 \ /
  Last update: 2020-08-03 20:45    [W:0.100 / U:0.136 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site