| Message ID | 20190527111152.16324-4-david@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v3,01/11] mm/memory_hotplug: Simplify and fix check_hotplug_memory_range() | expand |
On Mon 27-05-19 13:11:44, David Hildenbrand wrote: > Will come in handy when wanting to handle errors after > arch_add_memory(). I do not understand this. Why do you add a code for something that is not possible on this HW (based on the comment - is it still valid btw?) > Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> > Cc: Heiko Carstens <heiko.carstens@de.ibm.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Michal Hocko <mhocko@suse.com> > Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> > Cc: David Hildenbrand <david@redhat.com> > Cc: Vasily Gorbik <gor@linux.ibm.com> > Cc: Oscar Salvador <osalvador@suse.com> > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > arch/s390/mm/init.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > index d552e330fbcc..14955e0a9fcf 100644 > --- a/arch/s390/mm/init.c > +++ b/arch/s390/mm/init.c > @@ -243,12 +243,13 @@ int arch_add_memory(int nid, u64 start, u64 size, > void arch_remove_memory(int nid, u64 start, u64 size, > struct vmem_altmap *altmap) > { > - /* > - * There is no hardware or firmware interface which could trigger a > - * hot memory remove on s390. So there is nothing that needs to be > - * implemented. > - */ > - BUG(); > + unsigned long start_pfn = start >> PAGE_SHIFT; > + unsigned long nr_pages = size >> PAGE_SHIFT; > + struct zone *zone; > + > + zone = page_zone(pfn_to_page(start_pfn)); > + __remove_pages(zone, start_pfn, nr_pages, altmap); > + vmem_remove_mapping(start, size); > } > #endif > #endif /* CONFIG_MEMORY_HOTPLUG */ > -- > 2.20.1 >
On Mon 01-07-19 09:45:03, Michal Hocko wrote: > On Mon 27-05-19 13:11:44, David Hildenbrand wrote: > > Will come in handy when wanting to handle errors after > > arch_add_memory(). > > I do not understand this. Why do you add a code for something that is > not possible on this HW (based on the comment - is it still valid btw?) Same as the previous patch (drop it). > > Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> > > Cc: Heiko Carstens <heiko.carstens@de.ibm.com> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Michal Hocko <mhocko@suse.com> > > Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> > > Cc: David Hildenbrand <david@redhat.com> > > Cc: Vasily Gorbik <gor@linux.ibm.com> > > Cc: Oscar Salvador <osalvador@suse.com> > > Signed-off-by: David Hildenbrand <david@redhat.com> > > --- > > arch/s390/mm/init.c | 13 +++++++------ > > 1 file changed, 7 insertions(+), 6 deletions(-) > > > > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > > index d552e330fbcc..14955e0a9fcf 100644 > > --- a/arch/s390/mm/init.c > > +++ b/arch/s390/mm/init.c > > @@ -243,12 +243,13 @@ int arch_add_memory(int nid, u64 start, u64 size, > > void arch_remove_memory(int nid, u64 start, u64 size, > > struct vmem_altmap *altmap) > > { > > - /* > > - * There is no hardware or firmware interface which could trigger a > > - * hot memory remove on s390. So there is nothing that needs to be > > - * implemented. > > - */ > > - BUG(); > > + unsigned long start_pfn = start >> PAGE_SHIFT; > > + unsigned long nr_pages = size >> PAGE_SHIFT; > > + struct zone *zone; > > + > > + zone = page_zone(pfn_to_page(start_pfn)); > > + __remove_pages(zone, start_pfn, nr_pages, altmap); > > + vmem_remove_mapping(start, size); > > } > > #endif > > #endif /* CONFIG_MEMORY_HOTPLUG */ > > -- > > 2.20.1 > > > > -- > Michal Hocko > SUSE Labs
On 01.07.19 14:47, Michal Hocko wrote: > On Mon 01-07-19 09:45:03, Michal Hocko wrote: >> On Mon 27-05-19 13:11:44, David Hildenbrand wrote: >>> Will come in handy when wanting to handle errors after >>> arch_add_memory(). >> >> I do not understand this. Why do you add a code for something that is >> not possible on this HW (based on the comment - is it still valid btw?) > > Same as the previous patch (drop it). No. As the description says, this will be needed to handle errors in patch 6 cleanly. And BTW, with paravirtualied devices like virtio-pmem and virtio-mem, this will also see some other users in the future. Thanks. > >>> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> >>> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> >>> Cc: Andrew Morton <akpm@linux-foundation.org> >>> Cc: Michal Hocko <mhocko@suse.com> >>> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> >>> Cc: David Hildenbrand <david@redhat.com> >>> Cc: Vasily Gorbik <gor@linux.ibm.com> >>> Cc: Oscar Salvador <osalvador@suse.com> >>> Signed-off-by: David Hildenbrand <david@redhat.com> >>> --- >>> arch/s390/mm/init.c | 13 +++++++------ >>> 1 file changed, 7 insertions(+), 6 deletions(-) >>> >>> diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c >>> index d552e330fbcc..14955e0a9fcf 100644 >>> --- a/arch/s390/mm/init.c >>> +++ b/arch/s390/mm/init.c >>> @@ -243,12 +243,13 @@ int arch_add_memory(int nid, u64 start, u64 size, >>> void arch_remove_memory(int nid, u64 start, u64 size, >>> struct vmem_altmap *altmap) >>> { >>> - /* >>> - * There is no hardware or firmware interface which could trigger a >>> - * hot memory remove on s390. So there is nothing that needs to be >>> - * implemented. >>> - */ >>> - BUG(); >>> + unsigned long start_pfn = start >> PAGE_SHIFT; >>> + unsigned long nr_pages = size >> PAGE_SHIFT; >>> + struct zone *zone; >>> + >>> + zone = page_zone(pfn_to_page(start_pfn)); >>> + __remove_pages(zone, start_pfn, nr_pages, altmap); >>> + vmem_remove_mapping(start, size); >>> } >>> #endif >>> #endif /* CONFIG_MEMORY_HOTPLUG */ >>> -- >>> 2.20.1 >>> >> >> -- >> Michal Hocko >> SUSE Labs >
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index d552e330fbcc..14955e0a9fcf 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -243,12 +243,13 @@ int arch_add_memory(int nid, u64 start, u64 size, void arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) { - /* - * There is no hardware or firmware interface which could trigger a - * hot memory remove on s390. So there is nothing that needs to be - * implemented. - */ - BUG(); + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + + zone = page_zone(pfn_to_page(start_pfn)); + __remove_pages(zone, start_pfn, nr_pages, altmap); + vmem_remove_mapping(start, size); } #endif #endif /* CONFIG_MEMORY_HOTPLUG */
Will come in handy when wanting to handle errors after arch_add_memory(). Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Oscar Salvador <osalvador@suse.com> Signed-off-by: David Hildenbrand <david@redhat.com> --- arch/s390/mm/init.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)