search for: memory_device_publ

...include/linux/memremap.h index 1732dea030b2..995c62c5a48b 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -37,13 +37,6 @@ struct vmem_altmap { * A more complete discussion of unaddressable memory may be found in * include/linux/hmm.h and Documentation/vm/hmm.rst. * - * MEMORY_DEVICE_PUBLIC: - * Device memory that is cache coherent from device and CPU point of view. This - * is use on platform that have an advance system bus (like CAPI or CCIX). A - * driver can hotplug the device memory using ZONE_DEVICE and with that memory - * type. Any page of a process can be migrated to such m...

...h because it goes > > too far and removes the put_devmap_managed_page() call. > > release_pages only called put_devmap_managed_page for device public > pages. So I can't see how that is in any way a problem. It's a bug that the call to put_devmap_managed_page() was gated by MEMORY_DEVICE_PUBLIC in release_pages(). That path is also applicable to MEMORY_DEVICE_FSDAX because it needs to trigger the ->page_free() callback to wake up wait_on_var() via fsdax_pagefree(). So I guess you could argue that the MEMORY_DEVICE_PUBLIC removal patch left the original bug in place. In that sense we...

On Wed, Jun 26, 2019 at 09:00:47AM -0700, Dan Williams wrote: > [ add Ira ] > > On Wed, Jun 26, 2019 at 5:27 AM Christoph Hellwig <hch at lst.de> wrote: > > > > The code hasn't been used since it was added to the tree, and doesn't > > appear to actually be usable. > > > > Signed-off-by: Christoph Hellwig <hch at lst.de> > >

...ine bool is_device_public_page(const struct page *page) > { > return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && > IS_ENABLED(CONFIG_DEVICE_PUBLIC) && > is_zone_device_page(page) && > page->pgmap->type == MEMORY_DEVICE_PUBLIC; > } > > Which is called all over the place.. <sigh> yes but the earlier patch: [PATCH 03/22] mm: remove hmm_devmem_add_resource Removes the only place type is set to MEMORY_DEVICE_PUBLIC. So I think it is ok. Frankly I was wondering if we should remove the public type alto...

[ add Ira ] On Wed, Jun 26, 2019 at 5:27 AM Christoph Hellwig <hch at lst.de> wrote: > > The code hasn't been used since it was added to the tree, and doesn't > appear to actually be usable. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> > Acked-by: Michal Hocko <mhocko at suse.com>

...age *page) > >> { > >> return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && > >> IS_ENABLED(CONFIG_DEVICE_PUBLIC) && > >> is_zone_device_page(page) && > >> page->pgmap->type == MEMORY_DEVICE_PUBLIC; > >> } > >> > >> Which is called all over the place.. > > > > <sigh> yes but the earlier patch: > > > > [PATCH 03/22] mm: remove hmm_devmem_add_resource > > > > Removes the only place type is set to MEMORY_DEVICE_PUBLIC. &...

This function has never been used since it was first added to the kernel more than a year and a half ago, and if we ever grow a consumer of the MEMORY_DEVICE_PUBLIC infrastructure it can easily use devm_memremap_pages directly now that we've simplified the API for it. Signed-off-by: Christoph Hellwig <hch at lst.de> --- include/linux/hmm.h | 3 --- mm/hmm.c | 54 --------------------------------------------- 2 files changed, 57 deleti...

...ublic_page(const struct page *page) >> { >> return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && >> IS_ENABLED(CONFIG_DEVICE_PUBLIC) && >> is_zone_device_page(page) && >> page->pgmap->type == MEMORY_DEVICE_PUBLIC; >> } >> >> Which is called all over the place.. > > <sigh> yes but the earlier patch: > > [PATCH 03/22] mm: remove hmm_devmem_add_resource > > Removes the only place type is set to MEMORY_DEVICE_PUBLIC. > > So I think it is ok. Frankly I was...

On Thu, Jun 13, 2019 at 11:43:06AM +0200, Christoph Hellwig wrote: > This function has never been used since it was first added to the kernel > more than a year and a half ago, and if we ever grow a consumer of the > MEMORY_DEVICE_PUBLIC infrastructure it can easily use devm_memremap_pages > directly now that we've simplified the API for it. nit: Have we simplified the interface for devm_memremap_pages() at this point, or are you talking about later patches in this series. I checked this and all the called functions are...

This function has never been used since it was first added to the kernel more than a year and a half ago, and if we ever grow a consumer of the MEMORY_DEVICE_PUBLIC infrastructure it can easily use devm_memremap_pages directly. Signed-off-by: Christoph Hellwig <hch at lst.de> Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Reviewed-by: John Hubbard <jhubbard at nvidia.com> Acked-by: Michal Hocko <mhocko at suse.com> --- include/l...

On Wed, Jun 26, 2019 at 02:27:02PM +0200, Christoph Hellwig wrote: > This function has never been used since it was first added to the kernel > more than a year and a half ago, and if we ever grow a consumer of the > MEMORY_DEVICE_PUBLIC infrastructure it can easily use devm_memremap_pages > directly. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> > Reviewed-by: John Hubbard <jhubbard at nvidia.com> > Acked-by: Michal Hocko <mhocko...

On Fri, Jun 28, 2019 at 11:59:19AM -0700, Dan Williams wrote: > It's a bug that the call to put_devmap_managed_page() was gated by > MEMORY_DEVICE_PUBLIC in release_pages(). That path is also applicable > to MEMORY_DEVICE_FSDAX because it needs to trigger the ->page_free() > callback to wake up wait_on_var() via fsdax_pagefree(). > > So I guess you could argue that the MEMORY_DEVICE_PUBLIC removal patch > left the original bug i...

On Fri, Jun 28, 2019 at 12:02 PM Christoph Hellwig <hch at lst.de> wrote: > > On Fri, Jun 28, 2019 at 11:59:19AM -0700, Dan Williams wrote: > > It's a bug that the call to put_devmap_managed_page() was gated by > > MEMORY_DEVICE_PUBLIC in release_pages(). That path is also applicable > > to MEMORY_DEVICE_FSDAX because it needs to trigger the ->page_free() > > callback to wake up wait_on_var() via fsdax_pagefree(). > > > > So I guess you could argue that the MEMORY_DEVICE_PUBLIC removal patch > >...

On 6/13/19 12:44 PM, Jason Gunthorpe wrote: > On Thu, Jun 13, 2019 at 11:43:21AM +0200, Christoph Hellwig wrote: >> The code hasn't been used since it was added to the tree, and doesn't >> appear to actually be usable. Mark it as BROKEN until either a user >> comes along or we finally give up on it. >> >> Signed-off-by: Christoph Hellwig <hch at

On Fri, Jun 28, 2019 at 11:29 AM Jason Gunthorpe <jgg at mellanox.com> wrote: > > On Fri, Jun 28, 2019 at 10:10:12AM -0700, Dan Williams wrote: > > On Fri, Jun 28, 2019 at 10:08 AM Dan Williams <dan.j.williams at intel.com> wrote: > > > > > > On Fri, Jun 28, 2019 at 10:02 AM Jason Gunthorpe <jgg at mellanox.com> wrote: > > > > > >

...circuit here: static inline bool is_device_public_page(const struct page *page) { return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && IS_ENABLED(CONFIG_DEVICE_PUBLIC) && is_zone_device_page(page) && page->pgmap->type == MEMORY_DEVICE_PUBLIC; } Which is called all over the place.. So, yes, we really don't want any distro or something to turn this on until it has a use. Reviewed-by: Jason Gunthorpe <jgg at mellanox.com> Jason

On Thu, Jun 13, 2019 at 05:43:15PM -0700, Ira Weiny wrote: > <sigh> yes but the earlier patch: > > [PATCH 03/22] mm: remove hmm_devmem_add_resource > > Removes the only place type is set to MEMORY_DEVICE_PUBLIC. > > So I think it is ok. Frankly I was wondering if we should remove the public > type altogether but conceptually it seems ok. But I don't see any users of it > so... should we get rid of it in the code rather than turning the config off? That was my original idea. But the...

...dev_pagemap *pgmap) pgprot_t pgprot = PAGE_KERNEL; int error, nid, is_ram; + switch (pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { + WARN(1, "Device private memory not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_PUBLIC: + if (!IS_ENABLED(CONFIG_DEVICE_PUBLIC)) { + WARN(1, "Device public memory not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_FS_DAX: + if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || + IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { + WARN(1, "File system...

...e MEMORY_DEVICE_PRIVATE: > + if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { > + WARN(1, "Device private memory not supported\n"); > + return ERR_PTR(-EINVAL); > + } > + break; > + case MEMORY_DEVICE_PUBLIC: > + if (!IS_ENABLED(CONFIG_DEVICE_PUBLIC)) { > + WARN(1, "Device public memory not supported\n"); > + return ERR_PTR(-EINVAL); > + } > + break; > + case MEMORY_DEVICE_FS_DAX: &...

On Thu, Jun 13, 2019 at 11:43:21AM +0200, Christoph Hellwig wrote: > The code hasn't been used since it was added to the tree, and doesn't > appear to actually be usable. Mark it as BROKEN until either a user > comes along or we finally give up on it. > > Signed-off-by: Christoph Hellwig <hch at lst.de> > mm/Kconfig | 1 + > 1 file changed, 1 insertion(+) >