Messages in this thread | | | Subject | Re: [PATCH v1 0/4]mm: convert totalram_pages, totalhigh_pages and managed pages to atomic | From | Konstantin Khlebnikov <> | Date | Tue, 6 Nov 2018 11:37:02 +0300 |
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On 06.11.2018 11:30, Arun KS wrote: > On 2018-11-06 13:47, Konstantin Khlebnikov wrote: >> On 06.11.2018 8:38, Arun KS wrote: >>> Any comments? >> >> Looks good. >> Except unclear motivation behind this change. >> This should be in comment of one of patch. > > totalram_pages, zone->managed_pages and totalhigh_pages are sometimes modified outside managed_page_count_lock. Hence convert these variable > to atomic to avoid readers potentially seeing a store tear.
So, this is just theoretical issue or splat from sanitizer. After boot memory online\offline are strictly serialized by rw-semaphore.
> > Will update the comment. > > Regards, > Arun > >> >> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> >> >>> >>> Regards, >>> Arun >>> >>> On 2018-10-26 16:30, Arun KS wrote: >>>> This series convert totalram_pages, totalhigh_pages and >>>> zone->managed_pages to atomic variables. >>>> >>>> The patch was comiple tested on x86(x86_64_defconfig & i386_defconfig) >>>> on tip of linux-mmotm. And memory hotplug tested on arm64, but on an >>>> older version of kernel. >>>> >>>> Arun KS (4): >>>> mm: Fix multiple evaluvations of totalram_pages and managed_pages >>>> mm: Convert zone->managed_pages to atomic variable >>>> mm: convert totalram_pages and totalhigh_pages variables to atomic >>>> mm: Remove managed_page_count spinlock >>>> >>>> arch/csky/mm/init.c | 4 +- >>>> arch/powerpc/platforms/pseries/cmm.c | 10 ++-- >>>> arch/s390/mm/init.c | 2 +- >>>> arch/um/kernel/mem.c | 3 +- >>>> arch/x86/kernel/cpu/microcode/core.c | 5 +- >>>> drivers/char/agp/backend.c | 4 +- >>>> drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 2 +- >>>> drivers/gpu/drm/i915/i915_gem.c | 2 +- >>>> drivers/gpu/drm/i915/selftests/i915_gem_gtt.c | 4 +- >>>> drivers/hv/hv_balloon.c | 19 +++---- >>>> drivers/md/dm-bufio.c | 2 +- >>>> drivers/md/dm-crypt.c | 2 +- >>>> drivers/md/dm-integrity.c | 2 +- >>>> drivers/md/dm-stats.c | 2 +- >>>> drivers/media/platform/mtk-vpu/mtk_vpu.c | 2 +- >>>> drivers/misc/vmw_balloon.c | 2 +- >>>> drivers/parisc/ccio-dma.c | 4 +- >>>> drivers/parisc/sba_iommu.c | 4 +- >>>> drivers/staging/android/ion/ion_system_heap.c | 2 +- >>>> drivers/xen/xen-selfballoon.c | 6 +-- >>>> fs/ceph/super.h | 2 +- >>>> fs/file_table.c | 7 +-- >>>> fs/fuse/inode.c | 2 +- >>>> fs/nfs/write.c | 2 +- >>>> fs/nfsd/nfscache.c | 2 +- >>>> fs/ntfs/malloc.h | 2 +- >>>> fs/proc/base.c | 2 +- >>>> include/linux/highmem.h | 28 ++++++++++- >>>> include/linux/mm.h | 27 +++++++++- >>>> include/linux/mmzone.h | 15 +++--- >>>> include/linux/swap.h | 1 - >>>> kernel/fork.c | 5 +- >>>> kernel/kexec_core.c | 5 +- >>>> kernel/power/snapshot.c | 2 +- >>>> lib/show_mem.c | 2 +- >>>> mm/highmem.c | 4 +- >>>> mm/huge_memory.c | 2 +- >>>> mm/kasan/quarantine.c | 2 +- >>>> mm/memblock.c | 6 +-- >>>> mm/memory_hotplug.c | 4 +- >>>> mm/mm_init.c | 2 +- >>>> mm/oom_kill.c | 2 +- >>>> mm/page_alloc.c | 71 +++++++++++++-------------- >>>> mm/shmem.c | 7 +-- >>>> mm/slab.c | 2 +- >>>> mm/swap.c | 2 +- >>>> mm/util.c | 2 +- >>>> mm/vmalloc.c | 4 +- >>>> mm/vmstat.c | 4 +- >>>> mm/workingset.c | 2 +- >>>> mm/zswap.c | 4 +- >>>> net/dccp/proto.c | 7 +-- >>>> net/decnet/dn_route.c | 2 +- >>>> net/ipv4/tcp_metrics.c | 2 +- >>>> net/netfilter/nf_conntrack_core.c | 7 +-- >>>> net/netfilter/xt_hashlimit.c | 5 +- >>>> net/sctp/protocol.c | 7 +-- >>>> security/integrity/ima/ima_kexec.c | 2 +- >>>> 58 files changed, 195 insertions(+), 144 deletions(-)
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