• Kent Overstreet's avatar
    fix missing vmalloc.h includes · 0069455b
    Kent Overstreet authored
    Patch series "Memory allocation profiling", v6.
    
    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
         ...
    
    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/20240306182440.2003814-1-surenb@google.com/
    
    
    This patch (of 37):
    
    The next patch drops vmalloc.h from a system header in order to fix a
    circular dependency; this adds it to all the files that were pulling it in
    implicitly.
    
    [kent.overstreet@linux.dev: fix arch/alpha/lib/memcpy.c]
      Link: https://lkml.kernel.org/r/20240327002152.3339937-1-kent.overstreet@linux.dev
    [surenb@google.com: fix arch/x86/mm/numa_32.c]
      Link: https://lkml.kernel.org/r/20240402180933.1663992-1-surenb@google.com
    [kent.overstreet@linux.dev: a few places were depending on sizes.h]
      Link: https://lkml.kernel.org/r/20240404034744.1664840-1-kent.overstreet@linux.dev
    [arnd@arndb.de: fix mm/kasan/hw_tags.c]
      Link: https://lkml.kernel.org/r/20240404124435.3121534-1-arnd@kernel.org
    [surenb@google.com: fix arc build]
      Link: https://lkml.kernel.org/r/20240405225115.431056-1-surenb@google.com
    Link: https://lkml.kernel.org/r/20240321163705.3067592-1-surenb@google.com
    Link: https://lkml.kernel.org/r/20240321163705.3067592-2-surenb@google.comSigned-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
    Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
    Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Reviewed-by: default avatarPasha Tatashin <pasha.tatashin@soleen.com>
    Tested-by: default avatarKees Cook <keescook@chromium.org>
    Cc: Alexander Viro <viro@zeniv.linux.org.uk>
    Cc: Alex Gaynor <alex.gaynor@gmail.com>
    Cc: Alice Ryhl <aliceryhl@google.com>
    Cc: Andreas Hindborg <a.hindborg@samsung.com>
    Cc: Benno Lossin <benno.lossin@proton.me>
    Cc: "Björn Roy Baron" <bjorn3_gh@protonmail.com>
    Cc: Boqun Feng <boqun.feng@gmail.com>
    Cc: Christoph Lameter <cl@linux.com>
    Cc: Dennis Zhou <dennis@kernel.org>
    Cc: Gary Guo <gary@garyguo.net>
    Cc: Miguel Ojeda <ojeda@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Vlastimil Babka <vbabka@suse.cz>
    Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    0069455b
fault.c 42.4 KB