linux/lib/alloc_tag.c, branch v6.12

Merge tag 'sysctl-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl

2024-07-16T21:24:29Z

Pull sysctl updates from Joel Granados: - Remove "->procname == NULL" check when iterating through sysctl table arrays Removing sentinels in ctl_table arrays reduces the build time size and runtime memory consumed by ~64 bytes per array. With all ctl_table sentinels gone, the additional check for ->procname == NULL that worked in tandem with the ARRAY_SIZE to calculate the size of the ctl_table arrays is no longer needed and has been removed. The sysctl register functions now returns an error if a sentinel is used. - Preparation patches for sysctl constification Constifying ctl_table structs prevents the modification of proc_handler function pointers as they would reside in .rodata. The ctl_table arguments in sysctl utility functions are const qualified in preparation for a future treewide proc_handler argument constification commit. - Misc fixes Increase robustness of set_ownership by providing sane default ownership values in case the callee doesn't set them. Bound check proc_dou8vec_minmax to avoid loading buggy modules and give sysctl testing module a name to avoid compiler complaints. * tag 'sysctl-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: sysctl: Warn on an empty procname element sysctl: Remove ctl_table sentinel code comments sysctl: Remove "child" sysctl code comments sysctl: Remove superfluous empty allocations from sysctl internals sysctl: Replace nr_entries with ctl_table_size in new_links sysctl: Remove check for sentinel element in ctl_table arrays mm profiling: Remove superfluous sentinel element from ctl_table locking: Remove superfluous sentinel element from kern_lockdep_table sysctl: Add module description to sysctl-testing sysctl: constify ctl_table arguments of utility function utsname: constify ctl_table arguments of utility function sysctl: move the extra1/2 boundary check of u8 to sysctl_check_table_array sysctl: always initialize i_uid/i_gid

lib/alloc_tag: do not register sysctl interface when CONFIG_SYSCTL=n

2024-06-15T17:43:05Z

Memory allocation profiling is trying to register sysctl interface even when CONFIG_SYSCTL=n, resulting in proc_do_static_key() being undefined. Prevent that by skipping sysctl registration for such configurations. Link: https://lkml.kernel.org/r/20240601233831.617124-1-surenb@google.com Fixes: 22d407b164ff ("lib: add allocation tagging support for memory allocation profiling") Signed-off-by: Suren Baghdasaryan Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202405280616.wcOGWJEj-lkp@intel.com/ Acked-by: Vlastimil Babka Cc: Kent Overstreet Cc: Kees Cook Cc: Pasha Tatashin Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

mm profiling: Remove superfluous sentinel element from ctl_table

2024-06-13T08:50:52Z

This commit is part of a greater effort to remove all empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Removed sentinel from memory_allocation_profiling_sysctls Signed-off-by: Joel Granados

lib: add version into /proc/allocinfo output

2024-05-24T18:55:05Z

Add version string and a header at the beginning of /proc/allocinfo to allow later format changes. Example output: > head /proc/allocinfo allocinfo - version: 1.0 # 0 0 init/main.c:1314 func:do_initcalls 0 0 init/do_mounts.c:353 func:mount_nodev_root 0 0 init/do_mounts.c:187 func:mount_root_generic 0 0 init/do_mounts.c:158 func:do_mount_root 0 0 init/initramfs.c:493 func:unpack_to_rootfs 0 0 init/initramfs.c:492 func:unpack_to_rootfs 0 0 init/initramfs.c:491 func:unpack_to_rootfs 512 1 arch/x86/events/rapl.c:681 func:init_rapl_pmus 128 1 arch/x86/events/rapl.c:571 func:rapl_cpu_online [akpm@linux-foundation.org: remove stray newline from struct allocinfo_private] Link: https://lkml.kernel.org/r/20240514163128.3662251-1-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Pasha Tatashin Reviewed-by: Kees Cook Cc: Kent Overstreet Cc: Vlastimil Babka Signed-off-by: Andrew Morton

alloc_tag: Tighten file permissions on /proc/allocinfo

2024-04-26T03:55:59Z

The /proc/allocinfo file exposes a tremendous about of information about kernel build details, memory allocations (obviously), and potentially even image layout (due to ordering). As this is intended to be consumed by system owners (like /proc/slabinfo), use the same file permissions as there: 0400. Link: https://lkml.kernel.org/r/20240425200844.work.184-kees@kernel.org Signed-off-by: Kees Cook Cc: Kent Overstreet Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

lib: add memory allocations report in show_mem()

2024-04-26T03:55:57Z

Include allocations in show_mem reports. Link: https://lkml.kernel.org/r/20240321163705.3067592-33-surenb@google.com Signed-off-by: Kent Overstreet Signed-off-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton

lib: introduce early boot parameter to avoid page_ext memory overhead

2024-04-26T03:55:53Z

The highest memory overhead from memory allocation profiling comes from page_ext objects. This overhead exists even if the feature is disabled but compiled-in. To avoid it, introduce an early boot parameter that prevents page_ext object creation. The new boot parameter is a tri-state with possible values of 0|1|never. When it is set to "never" the memory allocation profiling support is disabled, and overhead is minimized (currently no page_ext objects are allocated, in the future more overhead might be eliminated). As a result we also lose ability to enable memory allocation profiling at runtime (because there is no space to store alloctag references). Runtime sysctrl becomes read-only if the early boot parameter was set to "never". Note that the default value of this boot parameter depends on the CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT configuration. When CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=n the boot parameter is set to "never", therefore eliminating any overhead. CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y results in boot parameter being set to 1 (enabled). This allows distributions to avoid any overhead by setting CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=n config and with no changes to the kernel command line. We reuse sysctl.vm.mem_profiling boot parameter name in order to avoid introducing yet another control. This change turns it into a tri-state early boot parameter. Link: https://lkml.kernel.org/r/20240321163705.3067592-16-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Kent Overstreet Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton

lib: introduce support for page allocation tagging

2024-04-26T03:55:53Z

Introduce helper functions to easily instrument page allocators by storing a pointer to the allocation tag associated with the code that allocated the page in a page_ext field. Link: https://lkml.kernel.org/r/20240321163705.3067592-15-surenb@google.com Signed-off-by: Suren Baghdasaryan Co-developed-by: Kent Overstreet Signed-off-by: Kent Overstreet Reviewed-by: Vlastimil Babka Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton

lib: add allocation tagging support for memory allocation profiling

2024-04-26T03:55:52Z

Introduce CONFIG_MEM_ALLOC_PROFILING which provides definitions to easily instrument memory allocators. It registers an "alloc_tags" codetag type with /proc/allocinfo interface to output allocation tag information when the feature is enabled. CONFIG_MEM_ALLOC_PROFILING_DEBUG is provided for debugging the memory allocation profiling instrumentation. Memory allocation profiling can be enabled or disabled at runtime using /proc/sys/vm/mem_profiling sysctl when CONFIG_MEM_ALLOC_PROFILING_DEBUG=n. CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT enables memory allocation profiling by default. [surenb@google.com: Documentation/filesystems/proc.rst: fix allocinfo title] Link: https://lkml.kernel.org/r/20240326073813.727090-1-surenb@google.com [surenb@google.com: do limited memory accounting for modules with ARCH_NEEDS_WEAK_PER_CPU] Link: https://lkml.kernel.org/r/20240402180933.1663992-2-surenb@google.com [klarasmodin@gmail.com: explicitly include irqflags.h in alloc_tag.h] Link: https://lkml.kernel.org/r/20240407133252.173636-1-klarasmodin@gmail.com [surenb@google.com: fix alloc_tag_init() to prevent passing NULL to PTR_ERR()] Link: https://lkml.kernel.org/r/20240417003349.2520094-1-surenb@google.com Link: https://lkml.kernel.org/r/20240321163705.3067592-14-surenb@google.com Signed-off-by: Suren Baghdasaryan Co-developed-by: Kent Overstreet Signed-off-by: Kent Overstreet Signed-off-by: Klara Modin Tested-by: Kees Cook Cc: Alexander Viro Cc: Alex Gaynor Cc: Alice Ryhl Cc: Andreas Hindborg Cc: Benno Lossin Cc: "Björn Roy Baron" Cc: Boqun Feng Cc: Christoph Lameter Cc: Dennis Zhou Cc: Gary Guo Cc: Miguel Ojeda Cc: Pasha Tatashin Cc: Peter Zijlstra Cc: Tejun Heo Cc: Vlastimil Babka Cc: Wedson Almeida Filho Signed-off-by: Andrew Morton