| Message ID | 20190725160207.19579-2-osalvador@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Allocate memmap from hotadded memory | expand |
On 25.07.19 18:02, Oscar Salvador wrote: > This patch introduces MHP_MEMMAP_ON_MEMORY flag, > and prepares the callers that add memory to take a "flags" parameter. > This "flags" parameter will be evaluated later on in Patch#3 > to init mhp_restrictions struct. > > The callers are: > > add_memory > __add_memory > add_memory_resource > > Unfortunately, we do not have a single entry point to add memory, as depending > on the requisites of the caller, they want to hook up in different places, > (e.g: Xen reserve_additional_memory()), so we have to spread the parameter > in the three callers. > > MHP_MEMMAP_ON_MEMORY flag parameter will specify to allocate memmaps > from the hot-added range. > If callers wants memmaps to be allocated per memory block, it will > have to call add_memory() variants in memory-block granularity > spanning the whole range, while if it wants to allocate memmaps > per whole memory range, just one call will do. > > Want to add 384MB (3 sections, 3 memory-blocks) > e.g: > > add_memory(0x1000, size_memory_block); > add_memory(0x2000, size_memory_block); > add_memory(0x3000, size_memory_block); > > [memblock#0 ] > [0 - 511 pfns ] - vmemmaps for section#0 > [512 - 32767 pfns ] - normal memory > > [memblock#1 ] > [32768 - 33279 pfns] - vmemmaps for section#1 > [33280 - 65535 pfns] - normal memory > > [memblock#2 ] > [65536 - 66047 pfns] - vmemmap for section#2 > [66048 - 98304 pfns] - normal memory I wouldn't even care about documenting this right now. We have no user so far, so spending 50% of the description on this topic isn't really needed IMHO :) > > or > add_memory(0x1000, size_memory_block * 3); > > [memblock #0 ] > [0 - 1533 pfns ] - vmemmap for section#{0-2} > [1534 - 98304 pfns] - normal memory > > When using larger memory blocks (1GB or 2GB), the principle is the same. > > Of course, per whole-range granularity is nicer when it comes to have a large > contigous area, while per memory-block granularity allows us to have flexibility > when removing the memory. E.g., in my virtio-mem I am currently adding all memory blocks separately either way (to guranatee that remove_memory() works cleanly - see __release_memory_resource()), and to control the amount of not-offlined memory blocks (e.g., to make user space is actually onlining them). As it's just a prototype, this might change of course in the future. > > Signed-off-by: Oscar Salvador <osalvador@suse.de> > --- > drivers/acpi/acpi_memhotplug.c | 2 +- > drivers/base/memory.c | 2 +- > drivers/dax/kmem.c | 2 +- > drivers/hv/hv_balloon.c | 2 +- > drivers/s390/char/sclp_cmd.c | 2 +- > drivers/xen/balloon.c | 2 +- > include/linux/memory_hotplug.h | 25 ++++++++++++++++++++++--- > mm/memory_hotplug.c | 10 +++++----- > 8 files changed, 33 insertions(+), 14 deletions(-) > > diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c > index e294f44a7850..d91b3584d4b2 100644 > --- a/drivers/acpi/acpi_memhotplug.c > +++ b/drivers/acpi/acpi_memhotplug.c > @@ -207,7 +207,7 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) > if (node < 0) > node = memory_add_physaddr_to_nid(info->start_addr); > > - result = __add_memory(node, info->start_addr, info->length); > + result = __add_memory(node, info->start_addr, info->length, 0); > > /* > * If the memory block has been used by the kernel, add_memory() > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 154d5d4a0779..d30d0f6c8ad0 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -521,7 +521,7 @@ static ssize_t probe_store(struct device *dev, struct device_attribute *attr, > > nid = memory_add_physaddr_to_nid(phys_addr); > ret = __add_memory(nid, phys_addr, > - MIN_MEMORY_BLOCK_SIZE * sections_per_block); > + MIN_MEMORY_BLOCK_SIZE * sections_per_block, 0); > > if (ret) > goto out; > diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c > index 3d0a7e702c94..e159184e0ba0 100644 > --- a/drivers/dax/kmem.c > +++ b/drivers/dax/kmem.c > @@ -65,7 +65,7 @@ int dev_dax_kmem_probe(struct device *dev) > new_res->flags = IORESOURCE_SYSTEM_RAM; > new_res->name = dev_name(dev); > > - rc = add_memory(numa_node, new_res->start, resource_size(new_res)); > + rc = add_memory(numa_node, new_res->start, resource_size(new_res), 0); > if (rc) { > release_resource(new_res); > kfree(new_res); > diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c > index 6fb4ea5f0304..beb92bc56186 100644 > --- a/drivers/hv/hv_balloon.c > +++ b/drivers/hv/hv_balloon.c > @@ -731,7 +731,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size, > > nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn)); > ret = add_memory(nid, PFN_PHYS((start_pfn)), > - (HA_CHUNK << PAGE_SHIFT)); > + (HA_CHUNK << PAGE_SHIFT), 0); > > if (ret) { > pr_err("hot_add memory failed error is %d\n", ret); > diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c > index 37d42de06079..f61026c7db7e 100644 > --- a/drivers/s390/char/sclp_cmd.c > +++ b/drivers/s390/char/sclp_cmd.c > @@ -406,7 +406,7 @@ static void __init add_memory_merged(u16 rn) > if (!size) > goto skip_add; > for (addr = start; addr < start + size; addr += block_size) > - add_memory(numa_pfn_to_nid(PFN_DOWN(addr)), addr, block_size); > + add_memory(numa_pfn_to_nid(PFN_DOWN(addr)), addr, block_size, 0); > skip_add: > first_rn = rn; > num = 1; > diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c > index 4e11de6cde81..e4934ce40478 100644 > --- a/drivers/xen/balloon.c > +++ b/drivers/xen/balloon.c > @@ -349,7 +349,7 @@ static enum bp_state reserve_additional_memory(void) > mutex_unlock(&balloon_mutex); > /* add_memory_resource() requires the device_hotplug lock */ > lock_device_hotplug(); > - rc = add_memory_resource(nid, resource); > + rc = add_memory_resource(nid, resource, 0); > unlock_device_hotplug(); > mutex_lock(&balloon_mutex); > > diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > index f46ea71b4ffd..45dece922d7c 100644 > --- a/include/linux/memory_hotplug.h > +++ b/include/linux/memory_hotplug.h > @@ -54,6 +54,25 @@ enum { > }; > > /* > + * We want memmap (struct page array) to be allocated from the hotadded range. > + * To do so, there are two possible ways depending on what the caller wants. > + * 1) Allocate memmap pages whole hot-added range. > + * Here the caller will only call any add_memory() variant with the whole > + * memory address. > + * 2) Allocate memmap pages per memblock > + * Here, the caller will call any add_memory() variant per memblock > + * granularity. > + * The former implies that we will use the beginning of the hot-added range > + * to store the memmap pages of the whole range, while the latter implies > + * that we will use the beginning of each memblock to store its own memmap > + * pages. Can you make this documentation only state how MHP_MEMMAP_ON_MEMORY works? (IOW, shrink it heavily to what we actually implement) > + * > + * Please note that this is only a hint, not a guarantee. Only selected > + * architectures support it with SPARSE_VMEMMAP. > + */ > +#define MHP_MEMMAP_ON_MEMORY (1UL<<1) > + > +/* > * Restrictions for the memory hotplug: > * flags: MHP_ flags > * altmap: alternative allocator for memmap array > @@ -340,9 +359,9 @@ static inline void __remove_memory(int nid, u64 start, u64 size) {} > #endif /* CONFIG_MEMORY_HOTREMOVE */ > > extern void __ref free_area_init_core_hotplug(int nid); > -extern int __add_memory(int nid, u64 start, u64 size); > -extern int add_memory(int nid, u64 start, u64 size); > -extern int add_memory_resource(int nid, struct resource *resource); > +extern int __add_memory(int nid, u64 start, u64 size, unsigned long flags); > +extern int add_memory(int nid, u64 start, u64 size, unsigned long flags); > +extern int add_memory_resource(int nid, struct resource *resource, unsigned long flags); > extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, > unsigned long nr_pages, struct vmem_altmap *altmap); > extern bool is_memblock_offlined(struct memory_block *mem); > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 9a82e12bd0e7..3d97c3711333 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1046,7 +1046,7 @@ static int online_memory_block(struct memory_block *mem, void *arg) > * > * we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG > */ > -int __ref add_memory_resource(int nid, struct resource *res) > +int __ref add_memory_resource(int nid, struct resource *res, unsigned long flags) > { > struct mhp_restrictions restrictions = {}; > u64 start, size; > @@ -1123,7 +1123,7 @@ int __ref add_memory_resource(int nid, struct resource *res) > } > > /* requires device_hotplug_lock, see add_memory_resource() */ > -int __ref __add_memory(int nid, u64 start, u64 size) > +int __ref __add_memory(int nid, u64 start, u64 size, unsigned long flags) > { > struct resource *res; > int ret; > @@ -1132,18 +1132,18 @@ int __ref __add_memory(int nid, u64 start, u64 size) > if (IS_ERR(res)) > return PTR_ERR(res); > > - ret = add_memory_resource(nid, res); > + ret = add_memory_resource(nid, res, flags); > if (ret < 0) > release_memory_resource(res); > return ret; > } > > -int add_memory(int nid, u64 start, u64 size) > +int add_memory(int nid, u64 start, u64 size, unsigned long flags) > { > int rc; > > lock_device_hotplug(); > - rc = __add_memory(nid, start, size); > + rc = __add_memory(nid, start, size, flags); > unlock_device_hotplug(); > > return rc; > Apart from the requested description/documentation changes Reviewed-by: David Hildenbrand <david@redhat.com>
On Fri, Jul 26, 2019 at 10:34:47AM +0200, David Hildenbrand wrote: > > Want to add 384MB (3 sections, 3 memory-blocks) > > e.g: > > > > add_memory(0x1000, size_memory_block); > > add_memory(0x2000, size_memory_block); > > add_memory(0x3000, size_memory_block); > > > > [memblock#0 ] > > [0 - 511 pfns ] - vmemmaps for section#0 > > [512 - 32767 pfns ] - normal memory > > > > [memblock#1 ] > > [32768 - 33279 pfns] - vmemmaps for section#1 > > [33280 - 65535 pfns] - normal memory > > > > [memblock#2 ] > > [65536 - 66047 pfns] - vmemmap for section#2 > > [66048 - 98304 pfns] - normal memory > > I wouldn't even care about documenting this right now. We have no user > so far, so spending 50% of the description on this topic isn't really > needed IMHO :) Fair enough, I could drop it. Was just trying to be extra clear. > > > > > or > > add_memory(0x1000, size_memory_block * 3); > > > > [memblock #0 ] > > [0 - 1533 pfns ] - vmemmap for section#{0-2} > > [1534 - 98304 pfns] - normal memory > > > > When using larger memory blocks (1GB or 2GB), the principle is the same. > > > > Of course, per whole-range granularity is nicer when it comes to have a large > > contigous area, while per memory-block granularity allows us to have flexibility > > when removing the memory. > > E.g., in my virtio-mem I am currently adding all memory blocks > separately either way (to guranatee that remove_memory() works cleanly - > see __release_memory_resource()), and to control the amount of > not-offlined memory blocks (e.g., to make user space is actually > onlining them). As it's just a prototype, this might change of course in > the future. What is virtio-mem for? Did it that raised from a need? Is it something you could try this patch on? > > /* > > + * We want memmap (struct page array) to be allocated from the hotadded range. > > + * To do so, there are two possible ways depending on what the caller wants. > > + * 1) Allocate memmap pages whole hot-added range. > > + * Here the caller will only call any add_memory() variant with the whole > > + * memory address. > > + * 2) Allocate memmap pages per memblock > > + * Here, the caller will call any add_memory() variant per memblock > > + * granularity. > > + * The former implies that we will use the beginning of the hot-added range > > + * to store the memmap pages of the whole range, while the latter implies > > + * that we will use the beginning of each memblock to store its own memmap > > + * pages. > > Can you make this documentation only state how MHP_MEMMAP_ON_MEMORY > works? (IOW, shrink it heavily to what we actually implement) Sure. > Apart from the requested description/documentation changes > > Reviewed-by: David Hildenbrand <david@redhat.com> Thanks for having a look David ;-) > > -- > > Thanks, > > David / dhildenb
>> >>> >>> or >>> add_memory(0x1000, size_memory_block * 3); >>> >>> [memblock #0 ] >>> [0 - 1533 pfns ] - vmemmap for section#{0-2} >>> [1534 - 98304 pfns] - normal memory >>> >>> When using larger memory blocks (1GB or 2GB), the principle is the same. >>> >>> Of course, per whole-range granularity is nicer when it comes to have a large >>> contigous area, while per memory-block granularity allows us to have flexibility >>> when removing the memory. >> >> E.g., in my virtio-mem I am currently adding all memory blocks >> separately either way (to guranatee that remove_memory() works cleanly - >> see __release_memory_resource()), and to control the amount of >> not-offlined memory blocks (e.g., to make user space is actually >> onlining them). As it's just a prototype, this might change of course in >> the future. > > What is virtio-mem for? Did it that raised from a need? > Is it something you could try this patch on? virtio-mem is a paravirtualized way of hotplugging/removing to/from a guest. (similar to, but different to e.g., the hv-balloon). It adds/removes memory to/from the system. In the long term, it will try to also act similar-but different to a balloon - but that will require more work. In the first shot, it's all about adding/removing memory in the smaller granularity possible. The old prototype was https://lwn.net/Articles/755423/ Since then, a lot changed. Some more updated information is at https://events.linuxfoundation.org/wp-content/uploads/2017/12/virtio-mem-Paravirtualized-Memory-David-Hildenbrand-Red-Hat-1.pdf There is also a recording of the presentation on youtube. The current prototype is unfortunately not in a state yet that allows me to test with this patch set - my Master's thesis consumed most of my energy during the last year. I just started hacking on it again.
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index e294f44a7850..d91b3584d4b2 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -207,7 +207,7 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) if (node < 0) node = memory_add_physaddr_to_nid(info->start_addr); - result = __add_memory(node, info->start_addr, info->length); + result = __add_memory(node, info->start_addr, info->length, 0); /* * If the memory block has been used by the kernel, add_memory() diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 154d5d4a0779..d30d0f6c8ad0 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -521,7 +521,7 @@ static ssize_t probe_store(struct device *dev, struct device_attribute *attr, nid = memory_add_physaddr_to_nid(phys_addr); ret = __add_memory(nid, phys_addr, - MIN_MEMORY_BLOCK_SIZE * sections_per_block); + MIN_MEMORY_BLOCK_SIZE * sections_per_block, 0); if (ret) goto out; diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 3d0a7e702c94..e159184e0ba0 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -65,7 +65,7 @@ int dev_dax_kmem_probe(struct device *dev) new_res->flags = IORESOURCE_SYSTEM_RAM; new_res->name = dev_name(dev); - rc = add_memory(numa_node, new_res->start, resource_size(new_res)); + rc = add_memory(numa_node, new_res->start, resource_size(new_res), 0); if (rc) { release_resource(new_res); kfree(new_res); diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 6fb4ea5f0304..beb92bc56186 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -731,7 +731,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size, nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn)); ret = add_memory(nid, PFN_PHYS((start_pfn)), - (HA_CHUNK << PAGE_SHIFT)); + (HA_CHUNK << PAGE_SHIFT), 0); if (ret) { pr_err("hot_add memory failed error is %d\n", ret); diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c index 37d42de06079..f61026c7db7e 100644 --- a/drivers/s390/char/sclp_cmd.c +++ b/drivers/s390/char/sclp_cmd.c @@ -406,7 +406,7 @@ static void __init add_memory_merged(u16 rn) if (!size) goto skip_add; for (addr = start; addr < start + size; addr += block_size) - add_memory(numa_pfn_to_nid(PFN_DOWN(addr)), addr, block_size); + add_memory(numa_pfn_to_nid(PFN_DOWN(addr)), addr, block_size, 0); skip_add: first_rn = rn; num = 1; diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 4e11de6cde81..e4934ce40478 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -349,7 +349,7 @@ static enum bp_state reserve_additional_memory(void) mutex_unlock(&balloon_mutex); /* add_memory_resource() requires the device_hotplug lock */ lock_device_hotplug(); - rc = add_memory_resource(nid, resource); + rc = add_memory_resource(nid, resource, 0); unlock_device_hotplug(); mutex_lock(&balloon_mutex); diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index f46ea71b4ffd..45dece922d7c 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -54,6 +54,25 @@ enum { }; /* + * We want memmap (struct page array) to be allocated from the hotadded range. + * To do so, there are two possible ways depending on what the caller wants. + * 1) Allocate memmap pages whole hot-added range. + * Here the caller will only call any add_memory() variant with the whole + * memory address. + * 2) Allocate memmap pages per memblock + * Here, the caller will call any add_memory() variant per memblock + * granularity. + * The former implies that we will use the beginning of the hot-added range + * to store the memmap pages of the whole range, while the latter implies + * that we will use the beginning of each memblock to store its own memmap + * pages. + * + * Please note that this is only a hint, not a guarantee. Only selected + * architectures support it with SPARSE_VMEMMAP. + */ +#define MHP_MEMMAP_ON_MEMORY (1UL<<1) + +/* * Restrictions for the memory hotplug: * flags: MHP_ flags * altmap: alternative allocator for memmap array @@ -340,9 +359,9 @@ static inline void __remove_memory(int nid, u64 start, u64 size) {} #endif /* CONFIG_MEMORY_HOTREMOVE */ extern void __ref free_area_init_core_hotplug(int nid); -extern int __add_memory(int nid, u64 start, u64 size); -extern int add_memory(int nid, u64 start, u64 size); -extern int add_memory_resource(int nid, struct resource *resource); +extern int __add_memory(int nid, u64 start, u64 size, unsigned long flags); +extern int add_memory(int nid, u64 start, u64 size, unsigned long flags); +extern int add_memory_resource(int nid, struct resource *resource, unsigned long flags); extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, unsigned long nr_pages, struct vmem_altmap *altmap); extern bool is_memblock_offlined(struct memory_block *mem); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 9a82e12bd0e7..3d97c3711333 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1046,7 +1046,7 @@ static int online_memory_block(struct memory_block *mem, void *arg) * * we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ -int __ref add_memory_resource(int nid, struct resource *res) +int __ref add_memory_resource(int nid, struct resource *res, unsigned long flags) { struct mhp_restrictions restrictions = {}; u64 start, size; @@ -1123,7 +1123,7 @@ int __ref add_memory_resource(int nid, struct resource *res) } /* requires device_hotplug_lock, see add_memory_resource() */ -int __ref __add_memory(int nid, u64 start, u64 size) +int __ref __add_memory(int nid, u64 start, u64 size, unsigned long flags) { struct resource *res; int ret; @@ -1132,18 +1132,18 @@ int __ref __add_memory(int nid, u64 start, u64 size) if (IS_ERR(res)) return PTR_ERR(res); - ret = add_memory_resource(nid, res); + ret = add_memory_resource(nid, res, flags); if (ret < 0) release_memory_resource(res); return ret; } -int add_memory(int nid, u64 start, u64 size) +int add_memory(int nid, u64 start, u64 size, unsigned long flags) { int rc; lock_device_hotplug(); - rc = __add_memory(nid, start, size); + rc = __add_memory(nid, start, size, flags); unlock_device_hotplug(); return rc;
This patch introduces MHP_MEMMAP_ON_MEMORY flag, and prepares the callers that add memory to take a "flags" parameter. This "flags" parameter will be evaluated later on in Patch#3 to init mhp_restrictions struct. The callers are: add_memory __add_memory add_memory_resource Unfortunately, we do not have a single entry point to add memory, as depending on the requisites of the caller, they want to hook up in different places, (e.g: Xen reserve_additional_memory()), so we have to spread the parameter in the three callers. MHP_MEMMAP_ON_MEMORY flag parameter will specify to allocate memmaps from the hot-added range. If callers wants memmaps to be allocated per memory block, it will have to call add_memory() variants in memory-block granularity spanning the whole range, while if it wants to allocate memmaps per whole memory range, just one call will do. Want to add 384MB (3 sections, 3 memory-blocks) e.g: add_memory(0x1000, size_memory_block); add_memory(0x2000, size_memory_block); add_memory(0x3000, size_memory_block); [memblock#0 ] [0 - 511 pfns ] - vmemmaps for section#0 [512 - 32767 pfns ] - normal memory [memblock#1 ] [32768 - 33279 pfns] - vmemmaps for section#1 [33280 - 65535 pfns] - normal memory [memblock#2 ] [65536 - 66047 pfns] - vmemmap for section#2 [66048 - 98304 pfns] - normal memory or add_memory(0x1000, size_memory_block * 3); [memblock #0 ] [0 - 1533 pfns ] - vmemmap for section#{0-2} [1534 - 98304 pfns] - normal memory When using larger memory blocks (1GB or 2GB), the principle is the same. Of course, per whole-range granularity is nicer when it comes to have a large contigous area, while per memory-block granularity allows us to have flexibility when removing the memory. Signed-off-by: Oscar Salvador <osalvador@suse.de> --- drivers/acpi/acpi_memhotplug.c | 2 +- drivers/base/memory.c | 2 +- drivers/dax/kmem.c | 2 +- drivers/hv/hv_balloon.c | 2 +- drivers/s390/char/sclp_cmd.c | 2 +- drivers/xen/balloon.c | 2 +- include/linux/memory_hotplug.h | 25 ++++++++++++++++++++++--- mm/memory_hotplug.c | 10 +++++----- 8 files changed, 33 insertions(+), 14 deletions(-)