From 1b862aecfbd419cdc4553645bf86d07554279bed Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 6 Jul 2017 15:37:45 -0700 Subject: mm, memory_hotplug: get rid of is_zone_device_section Device memory hotplug hooks into regular memory hotplug only half way. It needs memory sections to track struct pages but there is no need/desire to associate those sections with memory blocks and export them to the userspace via sysfs because they cannot be onlined anyway. This is currently expressed by for_device argument to arch_add_memory which then makes sure to associate the given memory range with ZONE_DEVICE. register_new_memory then relies on is_zone_device_section to distinguish special memory hotplug from the regular one. While this works now, later patches in this series want to move __add_zone outside of arch_add_memory path so we have to come up with something else. Add want_memblock down the __add_pages path and use it to control whether the section->memblock association should be done. arch_add_memory then just trivially want memblock for everything but for_device hotplug. remove_memory_section doesn't need is_zone_device_section either. We can simply skip all the memblock specific cleanup if there is no memblock for the given section. This shouldn't introduce any functional change. Link: http://lkml.kernel.org/r/20170515085827.16474-5-mhocko@kernel.org Signed-off-by: Michal Hocko Tested-by: Dan Williams Acked-by: Vlastimil Babka Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Balbir Singh Cc: Daniel Kiper Cc: David Rientjes Cc: Heiko Carstens Cc: Igor Mammedov Cc: Jerome Glisse Cc: Joonsoo Kim Cc: Martin Schwidefsky Cc: Mel Gorman Cc: Reza Arbab Cc: Tobias Regnery Cc: Toshi Kani Cc: Vitaly Kuznetsov Cc: Xishi Qiu Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 3348e60dd8ad..a3d549966b6a 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -195,7 +195,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device) continue; nr_pages = (start_pfn + size_pages > zone_end_pfn) ? zone_end_pfn - start_pfn : size_pages; - rc = __add_pages(nid, zone, start_pfn, nr_pages); + rc = __add_pages(nid, zone, start_pfn, nr_pages, !for_device); if (rc) break; start_pfn += nr_pages; -- cgit v1.2.3 From f1dd2cd13c4bbbc9a7c4617b3b034fa643de98fe Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 6 Jul 2017 15:38:11 -0700 Subject: mm, memory_hotplug: do not associate hotadded memory to zones until online The current memory hotplug implementation relies on having all the struct pages associate with a zone/node during the physical hotplug phase (arch_add_memory->__add_pages->__add_section->__add_zone). In the vast majority of cases this means that they are added to ZONE_NORMAL. This has been so since 9d99aaa31f59 ("[PATCH] x86_64: Support memory hotadd without sparsemem") and it wasn't a big deal back then because movable onlining didn't exist yet. Much later memory hotplug wanted to (ab)use ZONE_MOVABLE for movable onlining 511c2aba8f07 ("mm, memory-hotplug: dynamic configure movable memory and portion memory") and then things got more complicated. Rather than reconsidering the zone association which was no longer needed (because the memory hotplug already depended on SPARSEMEM) a convoluted semantic of zone shifting has been developed. Only the currently last memblock or the one adjacent to the zone_movable can be onlined movable. This essentially means that the online type changes as the new memblocks are added. Let's simulate memory hot online manually $ echo 0x100000000 > /sys/devices/system/memory/probe $ grep . /sys/devices/system/memory/memory32/valid_zones Normal Movable $ echo $((0x100000000+(128<<20))) > /sys/devices/system/memory/probe $ grep . /sys/devices/system/memory/memory3?/valid_zones /sys/devices/system/memory/memory32/valid_zones:Normal /sys/devices/system/memory/memory33/valid_zones:Normal Movable $ echo $((0x100000000+2*(128<<20))) > /sys/devices/system/memory/probe $ grep . /sys/devices/system/memory/memory3?/valid_zones /sys/devices/system/memory/memory32/valid_zones:Normal /sys/devices/system/memory/memory33/valid_zones:Normal /sys/devices/system/memory/memory34/valid_zones:Normal Movable $ echo online_movable > /sys/devices/system/memory/memory34/state $ grep . /sys/devices/system/memory/memory3?/valid_zones /sys/devices/system/memory/memory32/valid_zones:Normal /sys/devices/system/memory/memory33/valid_zones:Normal Movable /sys/devices/system/memory/memory34/valid_zones:Movable Normal This is an awkward semantic because an udev event is sent as soon as the block is onlined and an udev handler might want to online it based on some policy (e.g. association with a node) but it will inherently race with new blocks showing up. This patch changes the physical online phase to not associate pages with any zone at all. All the pages are just marked reserved and wait for the onlining phase to be associated with the zone as per the online request. There are only two requirements - existing ZONE_NORMAL and ZONE_MOVABLE cannot overlap - ZONE_NORMAL precedes ZONE_MOVABLE in physical addresses the latter one is not an inherent requirement and can be changed in the future. It preserves the current behavior and made the code slightly simpler. This is subject to change in future. This means that the same physical online steps as above will lead to the following state: Normal Movable /sys/devices/system/memory/memory32/valid_zones:Normal Movable /sys/devices/system/memory/memory33/valid_zones:Normal Movable /sys/devices/system/memory/memory32/valid_zones:Normal Movable /sys/devices/system/memory/memory33/valid_zones:Normal Movable /sys/devices/system/memory/memory34/valid_zones:Normal Movable /sys/devices/system/memory/memory32/valid_zones:Normal Movable /sys/devices/system/memory/memory33/valid_zones:Normal Movable /sys/devices/system/memory/memory34/valid_zones:Movable Implementation: The current move_pfn_range is reimplemented to check the above requirements (allow_online_pfn_range) and then updates the respective zone (move_pfn_range_to_zone), the pgdat and links all the pages in the pfn range with the zone/node. __add_pages is updated to not require the zone and only initializes sections in the range. This allowed to simplify the arch_add_memory code (s390 could get rid of quite some of code). devm_memremap_pages is the only user of arch_add_memory which relies on the zone association because it only hooks into the memory hotplug only half way. It uses it to associate the new memory with ZONE_DEVICE but doesn't allow it to be {on,off}lined via sysfs. This means that this particular code path has to call move_pfn_range_to_zone explicitly. The original zone shifting code is kept in place and will be removed in the follow up patch for an easier review. Please note that this patch also changes the original behavior when offlining a memory block adjacent to another zone (Normal vs. Movable) used to allow to change its movable type. This will be handled later. [richard.weiyang@gmail.com: simplify zone_intersects()] Link: http://lkml.kernel.org/r/20170616092335.5177-1-richard.weiyang@gmail.com [richard.weiyang@gmail.com: remove duplicate call for set_page_links] Link: http://lkml.kernel.org/r/20170616092335.5177-2-richard.weiyang@gmail.com [akpm@linux-foundation.org: remove unused local `i'] Link: http://lkml.kernel.org/r/20170515085827.16474-12-mhocko@kernel.org Signed-off-by: Michal Hocko Signed-off-by: Wei Yang Tested-by: Dan Williams Tested-by: Reza Arbab Acked-by: Heiko Carstens # For s390 bits Acked-by: Vlastimil Babka Cc: Martin Schwidefsky Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Balbir Singh Cc: Daniel Kiper Cc: David Rientjes Cc: Igor Mammedov Cc: Jerome Glisse Cc: Joonsoo Kim Cc: Mel Gorman Cc: Tobias Regnery Cc: Toshi Kani Cc: Vitaly Kuznetsov Cc: Xishi Qiu Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/init.c | 30 ++---------------------------- 1 file changed, 2 insertions(+), 28 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index a3d549966b6a..bfa918e3592b 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -168,41 +168,15 @@ unsigned long memory_block_size_bytes(void) #ifdef CONFIG_MEMORY_HOTPLUG int arch_add_memory(int nid, u64 start, u64 size, bool for_device) { - unsigned long zone_start_pfn, zone_end_pfn, nr_pages; unsigned long start_pfn = PFN_DOWN(start); unsigned long size_pages = PFN_DOWN(size); - pg_data_t *pgdat = NODE_DATA(nid); - struct zone *zone; - int rc, i; + int rc; rc = vmem_add_mapping(start, size); if (rc) return rc; - for (i = 0; i < MAX_NR_ZONES; i++) { - zone = pgdat->node_zones + i; - if (zone_idx(zone) != ZONE_MOVABLE) { - /* Add range within existing zone limits, if possible */ - zone_start_pfn = zone->zone_start_pfn; - zone_end_pfn = zone->zone_start_pfn + - zone->spanned_pages; - } else { - /* Add remaining range to ZONE_MOVABLE */ - zone_start_pfn = start_pfn; - zone_end_pfn = start_pfn + size_pages; - } - if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) - continue; - nr_pages = (start_pfn + size_pages > zone_end_pfn) ? - zone_end_pfn - start_pfn : size_pages; - rc = __add_pages(nid, zone, start_pfn, nr_pages, !for_device); - if (rc) - break; - start_pfn += nr_pages; - size_pages -= nr_pages; - if (!size_pages) - break; - } + rc = __add_pages(nid, start_pfn, size_pages, !for_device); if (rc) vmem_remove_mapping(start, size); return rc; -- cgit v1.2.3 From 3d79a728f9b2e6ddcce4e02c91c4de1076548a4c Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 6 Jul 2017 15:38:21 -0700 Subject: mm, memory_hotplug: replace for_device by want_memblock in arch_add_memory arch_add_memory gets for_device argument which then controls whether we want to create memblocks for created memory sections. Simplify the logic by telling whether we want memblocks directly rather than going through pointless negation. This also makes the api easier to understand because it is clear what we want rather than nothing telling for_device which can mean anything. This shouldn't introduce any functional change. Link: http://lkml.kernel.org/r/20170515085827.16474-13-mhocko@kernel.org Signed-off-by: Michal Hocko Tested-by: Dan Williams Acked-by: Vlastimil Babka Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Balbir Singh Cc: Daniel Kiper Cc: David Rientjes Cc: Heiko Carstens Cc: Igor Mammedov Cc: Jerome Glisse Cc: Joonsoo Kim Cc: Martin Schwidefsky Cc: Mel Gorman Cc: Reza Arbab Cc: Tobias Regnery Cc: Toshi Kani Cc: Vitaly Kuznetsov Cc: Xishi Qiu Cc: Yasuaki Ishimatsu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index bfa918e3592b..8111694ce55a 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -166,7 +166,7 @@ unsigned long memory_block_size_bytes(void) } #ifdef CONFIG_MEMORY_HOTPLUG -int arch_add_memory(int nid, u64 start, u64 size, bool for_device) +int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock) { unsigned long start_pfn = PFN_DOWN(start); unsigned long size_pages = PFN_DOWN(size); @@ -176,7 +176,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device) if (rc) return rc; - rc = __add_pages(nid, start_pfn, size_pages, !for_device); + rc = __add_pages(nid, start_pfn, size_pages, want_memblock); if (rc) vmem_remove_mapping(start, size); return rc; -- cgit v1.2.3 From e1073d1e7920946ac4776a619cc40668b9e1401b Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Thu, 6 Jul 2017 15:39:17 -0700 Subject: mm/hugetlb: clean up ARCH_HAS_GIGANTIC_PAGE This moves the #ifdef in C code to a Kconfig dependency. Also we move the gigantic_page_supported() function to be arch specific. This allows architectures to conditionally enable runtime allocation of gigantic huge page. Architectures like ppc64 supports different gigantic huge page size (16G and 1G) based on the translation mode selected. This provides an opportunity for ppc64 to enable runtime allocation only w.r.t 1G hugepage. No functional change in this patch. Link: http://lkml.kernel.org/r/1494995292-4443-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V Cc: Michael Ellerman (powerpc) Cc: Anshuman Khandual Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/Kconfig | 2 +- arch/s390/include/asm/hugetlb.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 37abe86e5bc9..7eeb75d758c1 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -68,7 +68,7 @@ config S390 select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_GCOV_PROFILE_ALL - select ARCH_HAS_GIGANTIC_PAGE + select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA select ARCH_HAS_KCOV select ARCH_HAS_SET_MEMORY select ARCH_HAS_SG_CHAIN diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h index cd546a245c68..89057b2cc8fe 100644 --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h @@ -112,4 +112,7 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot) return pte_modify(pte, newprot); } +#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE +static inline bool gigantic_page_supported(void) { return true; } +#endif #endif /* _ASM_S390_HUGETLB_H */ -- cgit v1.2.3 From 7868a2087ec13ec4a5df0c5e00999863be132ba8 Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Thu, 6 Jul 2017 15:39:42 -0700 Subject: mm/hugetlb: add size parameter to huge_pte_offset() A poisoned or migrated hugepage is stored as a swap entry in the page tables. On architectures that support hugepages consisting of contiguous page table entries (such as on arm64) this leads to ambiguity in determining the page table entry to return in huge_pte_offset() when a poisoned entry is encountered. Let's remove the ambiguity by adding a size parameter to convey additional information about the requested address. Also fixup the definition/usage of huge_pte_offset() throughout the tree. Link: http://lkml.kernel.org/r/20170522133604.11392-4-punit.agrawal@arm.com Signed-off-by: Punit Agrawal Acked-by: Steve Capper Cc: Catalin Marinas Cc: Will Deacon Cc: Tony Luck Cc: Fenghua Yu Cc: James Hogan (odd fixer:METAG ARCHITECTURE) Cc: Ralf Baechle (supporter:MIPS) Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Yoshinori Sato Cc: Rich Felker Cc: "David S. Miller" Cc: Chris Metcalf Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Alexander Viro Cc: Michal Hocko Cc: Mike Kravetz Cc: Naoya Horiguchi Cc: "Aneesh Kumar K.V" Cc: "Kirill A. Shutemov" Cc: Hillf Danton Cc: Mark Rutland Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/mm/hugetlbpage.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c index d3a5e39756f6..44a8e6f0391e 100644 --- a/arch/s390/mm/hugetlbpage.c +++ b/arch/s390/mm/hugetlbpage.c @@ -180,7 +180,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, return (pte_t *) pmdp; } -pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) +pte_t *huge_pte_offset(struct mm_struct *mm, + unsigned long addr, unsigned long sz) { pgd_t *pgdp; p4d_t *p4dp; -- cgit v1.2.3 From 9386fac34c7cbe39013410b01348e284652ca1cf Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Thu, 6 Jul 2017 15:39:46 -0700 Subject: mm/hugetlb: allow architectures to override huge_pte_clear() When unmapping a hugepage range, huge_pte_clear() is used to clear the page table entries that are marked as not present. huge_pte_clear() internally just ends up calling pte_clear() which does not correctly deal with hugepages consisting of contiguous page table entries. Add a size argument to address this issue and allow architectures to override huge_pte_clear() by wrapping it in a #ifndef block. Update s390 implementation with the size parameter as well. Note that the change only affects huge_pte_clear() - the other generic hugetlb functions don't need any change. Link: http://lkml.kernel.org/r/20170522162555.4313-1-punit.agrawal@arm.com Signed-off-by: Punit Agrawal Acked-by: Martin Schwidefsky [s390 bits] Cc: Heiko Carstens Cc: Arnd Bergmann Cc: "Aneesh Kumar K.V" Cc: Mike Kravetz Cc: Catalin Marinas Cc: Will Deacon Cc: Naoya Horiguchi Cc: "Kirill A. Shutemov" Cc: Steve Capper Cc: Mark Rutland Cc: Hillf Danton Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/include/asm/hugetlb.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h index 89057b2cc8fe..d95869ce3ca2 100644 --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h @@ -39,7 +39,7 @@ static inline int prepare_hugepage_range(struct file *file, #define arch_clear_hugepage_flags(page) do { } while (0) static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr, - pte_t *ptep) + pte_t *ptep, unsigned long sz) { if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) pte_val(*ptep) = _REGION3_ENTRY_EMPTY; -- cgit v1.2.3