On Thu, May 11, 2023 at 03:02:55PM +0100, Matthew Wilcox wrote:
> We also talked about moving x86 to always RCU-free page tables in
> order to make accessing /proc/$pid/smaps lockless. I believe Michel
> is going to take a swing at this project.
Shouldn't be too controversial I think -- effectiv
Hi,
On Thu, May 11, 2023 at 03:02:55PM +0100, Matthew Wilcox wrote:
> On Wed, May 10, 2023 at 09:35:44PM -0700, Hugh Dickins wrote:
> > On Wed, 10 May 2023, Matthew Wilcox wrote:
> >
> > I don't really understand why you're going down a remove-CONFIG_HIGHPTE
> > route: I thought you were motivate
On Thu, 11 May 2023, Matthew Wilcox wrote:
>
> I was thinking that removing CONFIG_HIGHPTE might simplify the page
> fault handling path a little, but now I've looked at it some more, and
> I'm not sure there's any simplification to be had. It should probably
> use kmap_local instead of kmap_atom
On Wed, May 10, 2023 at 09:35:44PM -0700, Hugh Dickins wrote:
> On Wed, 10 May 2023, Matthew Wilcox wrote:
> > On Tue, May 09, 2023 at 09:39:13PM -0700, Hugh Dickins wrote:
> > > Two: pte_offset_map() will need to do an rcu_read_lock(), with the
> > > corresponding rcu_read_unlock() in pte_unmap().
On Wed, 10 May 2023, Matthew Wilcox wrote:
> On Tue, May 09, 2023 at 09:39:13PM -0700, Hugh Dickins wrote:
> > Two: pte_offset_map() will need to do an rcu_read_lock(), with the
> > corresponding rcu_read_unlock() in pte_unmap(). But most architectures
> > never supported CONFIG_HIGHPTE, so some d
On Tue, May 09, 2023 at 09:39:13PM -0700, Hugh Dickins wrote:
> Two: pte_offset_map() will need to do an rcu_read_lock(), with the
> corresponding rcu_read_unlock() in pte_unmap(). But most architectures
> never supported CONFIG_HIGHPTE, so some don't always call pte_unmap()
> after pte_offset_map
Here is a series of patches to various architectures, based on v6.4-rc1:
preparing for changes expected to follow in mm, affecting pte_offset_map()
and pte_offset_map_lock().
In a week or two, I intend to post a separate series, of equivalent
preparations in mm. These two series are "independent"
