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AJvYcCUz03muEmlvBjwU19E7FI7+nu9VCbYMdNdJLFdiCioijhBL7ThrvZbpWKSMfKMRcDq8jOiNmt+MoNt100FP/XN9MlT1wkXR10o+auPOuA== X-Gm-Message-State: AOJu0YzG83fKBnWB/6mVkh9UtG0K115wQlsalWfIz21zEJNhYBIq3s7t bDpoLkWRaWKDDFQjChkJzvxLRgq9Nk+ozXSP6/CGdrEuh4kZ/+F0BtdQfT1VH63BcQ95KSACdI8 qSQ== X-Google-Smtp-Source: AGHT+IFxWhscAtmHFqVARupfDbCnYirPYeuewmxRn+Ji3V4MrmINBlSy8mq1BztHmr3T3yFBdMS18fz4TYU= X-Received: from surenb-desktop.mtv.corp.google.com ([2620:15c:211:201:85f0:e3db:db05:85e2]) (user=surenb job=sendgmr) by 2002:a05:6902:1004:b0:dc2:3441:897f with SMTP id w4-20020a056902100400b00dc23441897fmr3842720ybt.6.1709749484713; Wed, 06 Mar 2024 10:24:44 -0800 (PST) Date: Wed, 6 Mar 2024 10:23:58 -0800 Precedence: bulk X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.44.0.278.ge034bb2e1d-goog Message-ID: <20240306182440.2003814-1-surenb@google.com> Subject: [PATCH v5 00/37] Memory allocation profiling From: Suren Baghdasaryan To: akpm@linux-foundation.org Cc: kent.overstreet@linux.dev, mhocko@suse.com, vbabka@suse.cz, hannes@cmpxchg.org, roman.gushchin@linux.dev, mgorman@suse.de, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, penguin-kernel@i-love.sakura.ne.jp, corbet@lwn.net, void@manifault.com, peterz@infradead.org, juri.lelli@redhat.com, catalin.marinas@arm.com, will@kernel.org, arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, peterx@redhat.com, david@redhat.com, axboe@kernel.dk, mcgrof@kernel.org, masahiroy@kernel.org, nathan@kernel.org, dennis@kernel.org, jhubbard@nvidia.com, tj@kernel.org, muchun.song@linux.dev, rppt@kernel.org, paulmck@kernel.org, pasha.tatashin@soleen.com, yosryahmed@google.com, yuzhao@google.com, dhowells@redhat.com, hughd@google.com, andreyknvl@gmail.com, keescook@chromium.org, ndesaulniers@google.com, vvvvvv@google.com, gregkh@linuxfoundation.org, ebiggers@google.com, ytcoode@gmail.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, bristot@redhat.com, vschneid@redhat.com, cl@linux.com, penberg@kernel.org, iamjoonsoo.kim@lge.com, 42.hyeyoo@gmail.com, glider@google.com, elver@google.com, dvyukov@google.com, shakeelb@google.com, songmuchun@bytedance.com, jbaron@akamai.com, aliceryhl@google.com, rientjes@google.com, minchan@google.com, kaleshsingh@google.com, surenb@google.com, kernel-team@android.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, kasan-dev@googlegroups.com, cgroups@vger.kernel.org Rebased over mm-unstable. Overview: Low overhead [1] per-callsite memory allocation profiling. Not just for debug kernels, overhead low enough to be deployed in production. Example output: root@moria-kvm:~# sort -rn /proc/allocinfo 127664128 31168 mm/page_ext.c:270 func:alloc_page_ext 56373248 4737 mm/slub.c:2259 func:alloc_slab_page 14880768 3633 mm/readahead.c:247 func:page_cache_ra_unbounded 14417920 3520 mm/mm_init.c:2530 func:alloc_large_system_hash 13377536 234 block/blk-mq.c:3421 func:blk_mq_alloc_rqs 11718656 2861 mm/filemap.c:1919 func:__filemap_get_folio 9192960 2800 kernel/fork.c:307 func:alloc_thread_stack_node 4206592 4 net/netfilter/nf_conntrack_core.c:2567 func:nf_ct_alloc_hashtable 4136960 1010 drivers/staging/ctagmod/ctagmod.c:20 [ctagmod] func:ctagmod_start 3940352 962 mm/memory.c:4214 func:alloc_anon_folio 2894464 22613 fs/kernfs/dir.c:615 func:__kernfs_new_node ... Since v4 [2]: - Added Reviewed-by, per Pasha Tatashin, Vlastimil Babka, Alice Ryhl - Changed slab_free_freelist_hook() to use __fastpath_inline, per Pasha Tatashin - Removed [3] as it is already Ack'ed and merged into in mm-unstable - Moved alloc_slab_obj_exts(), prepare_slab_obj_exts_hook() and alloc_tagging_slab_free_hook() into slub.c, per Vlastimil Babka - Removed drive-by spacing fixups, per Vlastimil Babka - Restored early memcg_kmem_online() check before calling free_slab_obj_exts(), per Vlastimil Babka - Added pr_warn() when module can't be unloaded, per Vlastimil Babka - Dropped __alloc_tag_sub() and alloc_tag_sub_noalloc(), per Vlastimil Babka - Fixed alloc_tag_add() to check for tag to be valid, per Vlastimil Babka - Moved alloc_tag_ref_set() where it's first used - Added a patch introducing a tristate early boot parameter, per Vlastimil Babka - Updated description for page splitting patch, per Vlastimil Babka - Added a patch fixing non-compound page accounting in __free_pages(), per Vlastimil Babka - Added early mem_alloc_profiling_enabled() checks in alloc_tagging_slab_free_hook() and prepare_slab_obj_exts_hook(), per Vlastimil Babka - Moved rust krealloc() helper patch before krealloc() is redefined, per Alice Ryhl - Replaced printk(KERN_NOTICE...) with pr_notice(), per Vlastimil Babka - Fixed codetag_{un}load_module() redefinition for CONFIG_MODULE=n, per kernel test robot - Updated documentation to describe new early boot parameter - Rebased over mm-unstable Usage: kconfig options: - CONFIG_MEM_ALLOC_PROFILING - CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT - CONFIG_MEM_ALLOC_PROFILING_DEBUG adds warnings for allocations that weren't accounted because of a missing annotation sysctl: /proc/sys/vm/mem_profiling Runtime info: /proc/allocinfo Notes: [1]: Overhead To measure the overhead we are comparing the following configurations: (1) Baseline with CONFIG_MEMCG_KMEM=n (2) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n) (3) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y) (4) Enabled at runtime (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n && /proc/sys/vm/mem_profiling=1) (5) Baseline with CONFIG_MEMCG_KMEM=y && allocating with __GFP_ACCOUNT (6) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n) && CONFIG_MEMCG_KMEM=y (7) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y && CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y) && CONFIG_MEMCG_KMEM=y Performance overhead: To evaluate performance we implemented an in-kernel test executing multiple get_free_page/free_page and kmalloc/kfree calls with allocation sizes growing from 8 to 240 bytes with CPU frequency set to max and CPU affinity set to a specific CPU to minimize the noise. Below are results from running the test on Ubuntu 22.04.2 LTS with 6.8.0-rc1 kernel on 56 core Intel Xeon: kmalloc pgalloc (1 baseline) 6.764s 16.902s (2 default disabled) 6.793s (+0.43%) 17.007s (+0.62%) (3 default enabled) 7.197s (+6.40%) 23.666s (+40.02%) (4 runtime enabled) 7.405s (+9.48%) 23.901s (+41.41%) (5 memcg) 13.388s (+97.94%) 48.460s (+186.71%) (6 def disabled+memcg) 13.332s (+97.10%) 48.105s (+184.61%) (7 def enabled+memcg) 13.446s (+98.78%) 54.963s (+225.18%) Memory overhead: Kernel size: text data bss dec diff (1) 26515311 18890222 17018880 62424413 (2) 26524728 19423818 16740352 62688898 264485 (3) 26524724 19423818 16740352 62688894 264481 (4) 26524728 19423818 16740352 62688898 264485 (5) 26541782 18964374 16957440 62463596 39183 Memory consumption on a 56 core Intel CPU with 125GB of memory: Code tags: 192 kB PageExts: 262144 kB (256MB) SlabExts: 9876 kB (9.6MB) PcpuExts: 512 kB (0.5MB) Total overhead is 0.2% of total memory. Benchmarks: Hackbench tests run 100 times: hackbench -s 512 -l 200 -g 15 -f 25 -P baseline disabled profiling enabled profiling avg 0.3543 0.3559 (+0.0016) 0.3566 (+0.0023) stdev 0.0137 0.0188 0.0077 hackbench -l 10000 baseline disabled profiling enabled profiling avg 6.4218 6.4306 (+0.0088) 6.5077 (+0.0859) stdev 0.0933 0.0286 0.0489 stress-ng tests: stress-ng --class memory --seq 4 -t 60 stress-ng --class cpu --seq 4 -t 60 Results posted at: https://evilpiepirate.org/~kent/memalloc_prof_v4_stress-ng/ [2] https://lore.kernel.org/all/20240221194052.927623-1-surenb@google.com/ [3] https://lore.kernel.org/all/20240221194052.927623-7-surenb@google.com/ Kent Overstreet (13): fix missing vmalloc.h includes asm-generic/io.h: Kill vmalloc.h dependency mm/slub: Mark slab_free_freelist_hook() __always_inline scripts/kallysms: Always include __start and __stop symbols fs: Convert alloc_inode_sb() to a macro rust: Add a rust helper for krealloc() mempool: Hook up to memory allocation profiling mm: percpu: Introduce pcpuobj_ext mm: percpu: Add codetag reference into pcpuobj_ext mm: vmalloc: Enable memory allocation profiling rhashtable: Plumb through alloc tag MAINTAINERS: Add entries for code tagging and memory allocation profiling memprofiling: Documentation Suren Baghdasaryan (24): mm: introduce slabobj_ext to support slab object extensions mm: introduce __GFP_NO_OBJ_EXT flag to selectively prevent slabobj_ext creation mm/slab: introduce SLAB_NO_OBJ_EXT to avoid obj_ext creation slab: objext: introduce objext_flags as extension to page_memcg_data_flags lib: code tagging framework lib: code tagging module support lib: prevent module unloading if memory is not freed lib: add allocation tagging support for memory allocation profiling lib: introduce support for page allocation tagging lib: introduce early boot parameter to avoid page_ext memory overhead mm: percpu: increase PERCPU_MODULE_RESERVE to accommodate allocation tags change alloc_pages name in dma_map_ops to avoid name conflicts mm: enable page allocation tagging mm: create new codetag references during page splitting mm: fix non-compound multi-order memory accounting in __free_pages mm/page_ext: enable early_page_ext when CONFIG_MEM_ALLOC_PROFILING_DEBUG=y lib: add codetag reference into slabobj_ext mm/slab: add allocation accounting into slab allocation and free paths mm/slab: enable slab allocation tagging for kmalloc and friends mm: percpu: enable per-cpu allocation tagging lib: add memory allocations report in show_mem() codetag: debug: skip objext checking when it's for objext itself codetag: debug: mark codetags for reserved pages as empty codetag: debug: introduce OBJEXTS_ALLOC_FAIL to mark failed slab_ext allocations Documentation/admin-guide/sysctl/vm.rst | 16 + Documentation/filesystems/proc.rst | 29 ++ Documentation/mm/allocation-profiling.rst | 91 +++++ MAINTAINERS | 17 + arch/alpha/kernel/pci_iommu.c | 2 +- arch/alpha/lib/checksum.c | 1 + arch/alpha/lib/fpreg.c | 1 + arch/alpha/lib/memcpy.c | 1 + arch/arm/kernel/irq.c | 1 + arch/arm/kernel/traps.c | 1 + arch/arm64/kernel/efi.c | 1 + arch/loongarch/include/asm/kfence.h | 1 + arch/mips/jazz/jazzdma.c | 2 +- arch/powerpc/kernel/dma-iommu.c | 2 +- arch/powerpc/kernel/iommu.c | 1 + arch/powerpc/mm/mem.c | 1 + arch/powerpc/platforms/ps3/system-bus.c | 4 +- arch/powerpc/platforms/pseries/vio.c | 2 +- arch/riscv/kernel/elf_kexec.c | 1 + arch/riscv/kernel/probes/kprobes.c | 1 + arch/s390/kernel/cert_store.c | 1 + arch/s390/kernel/ipl.c | 1 + arch/x86/include/asm/io.h | 1 + arch/x86/kernel/amd_gart_64.c | 2 +- arch/x86/kernel/cpu/sgx/main.c | 1 + arch/x86/kernel/irq_64.c | 1 + arch/x86/mm/fault.c | 1 + drivers/accel/ivpu/ivpu_mmu_context.c | 1 + drivers/gpu/drm/gma500/mmu.c | 1 + drivers/gpu/drm/i915/gem/i915_gem_pages.c | 1 + .../gpu/drm/i915/gem/selftests/mock_dmabuf.c | 1 + drivers/gpu/drm/i915/gt/shmem_utils.c | 1 + drivers/gpu/drm/i915/gvt/firmware.c | 1 + drivers/gpu/drm/i915/gvt/gtt.c | 1 + drivers/gpu/drm/i915/gvt/handlers.c | 1 + drivers/gpu/drm/i915/gvt/mmio.c | 1 + drivers/gpu/drm/i915/gvt/vgpu.c | 1 + drivers/gpu/drm/i915/intel_gvt.c | 1 + drivers/gpu/drm/imagination/pvr_vm_mips.c | 1 + drivers/gpu/drm/mediatek/mtk_drm_gem.c | 1 + drivers/gpu/drm/omapdrm/omap_gem.c | 1 + drivers/gpu/drm/v3d/v3d_bo.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_binding.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_cmd.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_devcaps.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c | 1 + drivers/gpu/drm/xen/xen_drm_front_gem.c | 1 + drivers/hwtracing/coresight/coresight-trbe.c | 1 + drivers/iommu/dma-iommu.c | 2 +- .../marvell/octeon_ep/octep_pfvf_mbox.c | 1 + .../net/ethernet/microsoft/mana/hw_channel.c | 1 + drivers/parisc/ccio-dma.c | 2 +- drivers/parisc/sba_iommu.c | 2 +- drivers/platform/x86/uv_sysfs.c | 1 + drivers/scsi/mpi3mr/mpi3mr_transport.c | 2 + drivers/staging/media/atomisp/pci/hmm/hmm.c | 2 +- drivers/vfio/pci/pds/dirty.c | 1 + drivers/virt/acrn/mm.c | 1 + drivers/virtio/virtio_mem.c | 1 + drivers/xen/grant-dma-ops.c | 2 +- drivers/xen/swiotlb-xen.c | 2 +- include/asm-generic/codetag.lds.h | 14 + include/asm-generic/io.h | 1 - include/asm-generic/vmlinux.lds.h | 3 + include/linux/alloc_tag.h | 205 +++++++++++ include/linux/codetag.h | 81 +++++ include/linux/dma-map-ops.h | 2 +- include/linux/fortify-string.h | 5 +- include/linux/fs.h | 6 +- include/linux/gfp.h | 126 ++++--- include/linux/gfp_types.h | 11 + include/linux/memcontrol.h | 56 ++- include/linux/mempool.h | 73 ++-- include/linux/mm.h | 9 + include/linux/mm_types.h | 4 +- include/linux/page_ext.h | 1 - include/linux/pagemap.h | 9 +- include/linux/pds/pds_common.h | 2 + include/linux/percpu.h | 27 +- include/linux/pgalloc_tag.h | 134 +++++++ include/linux/rhashtable-types.h | 11 +- include/linux/sched.h | 24 ++ include/linux/slab.h | 175 +++++----- include/linux/string.h | 4 +- include/linux/vmalloc.h | 60 +++- include/rdma/rdmavt_qp.h | 1 + init/Kconfig | 4 + kernel/dma/mapping.c | 4 +- kernel/kallsyms_selftest.c | 2 +- kernel/module/main.c | 29 +- lib/Kconfig.debug | 31 ++ lib/Makefile | 3 + lib/alloc_tag.c | 243 +++++++++++++ lib/codetag.c | 283 +++++++++++++++ lib/rhashtable.c | 28 +- mm/compaction.c | 7 +- mm/debug_vm_pgtable.c | 1 + mm/filemap.c | 6 +- mm/huge_memory.c | 2 + mm/kfence/core.c | 14 +- mm/kfence/kfence.h | 4 +- mm/memcontrol.c | 56 +-- mm/mempolicy.c | 52 +-- mm/mempool.c | 36 +- mm/mm_init.c | 13 +- mm/nommu.c | 64 ++-- mm/page_alloc.c | 77 +++-- mm/page_ext.c | 13 + mm/page_owner.c | 2 +- mm/percpu-internal.h | 26 +- mm/percpu.c | 120 +++---- mm/show_mem.c | 26 ++ mm/slab.h | 51 ++- mm/slab_common.c | 6 +- mm/slub.c | 327 +++++++++++++++--- mm/util.c | 44 +-- mm/vmalloc.c | 88 ++--- rust/helpers.c | 8 + scripts/kallsyms.c | 13 + scripts/module.lds.S | 7 + sound/pci/hda/cs35l41_hda.c | 1 + 123 files changed, 2305 insertions(+), 657 deletions(-) create mode 100644 Documentation/mm/allocation-profiling.rst create mode 100644 include/asm-generic/codetag.lds.h create mode 100644 include/linux/alloc_tag.h create mode 100644 include/linux/codetag.h create mode 100644 include/linux/pgalloc_tag.h create mode 100644 lib/alloc_tag.c create mode 100644 lib/codetag.c base-commit: b38c34939fe4735b8716511f0a98814be3865a1b