kernel/linux.git/include/trace/stages, branch master

Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-04-15T19:59:16+00:00

Pull MM updates from Andrew Morton: - "maple_tree: Replace big node with maple copy" (Liam Howlett) Mainly prepararatory work for ongoing development but it does reduce stack usage and is an improvement. - "mm, swap: swap table phase III: remove swap_map" (Kairui Song) Offers memory savings by removing the static swap_map. It also yields some CPU savings and implements several cleanups. - "mm: memfd_luo: preserve file seals" (Pratyush Yadav) File seal preservation to LUO's memfd code - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan Chen) Additional userspace stats reportng to zswap - "arch, mm: consolidate empty_zero_page" (Mike Rapoport) Some cleanups for our handling of ZERO_PAGE() and zero_pfn - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu Han) A robustness improvement and some cleanups in the kmemleak code - "Improve khugepaged scan logic" (Vernon Yang) Improve khugepaged scan logic and reduce CPU consumption by prioritizing scanning tasks that access memory frequently - "Make KHO Stateless" (Jason Miu) Simplify Kexec Handover by transitioning KHO from an xarray-based metadata tracking system with serialization to a radix tree data structure that can be passed directly to the next kernel - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas Ballasi and Steven Rostedt) Enhance vmscan's tracepointing - "mm: arch/shstk: Common shadow stack mapping helper and VM_NOHUGEPAGE" (Catalin Marinas) Cleanup for the shadow stack code: remove per-arch code in favour of a generic implementation - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin) Fix a WARN() which can be emitted the KHO restores a vmalloc area - "mm: Remove stray references to pagevec" (Tal Zussman) Several cleanups, mainly udpating references to "struct pagevec", which became folio_batch three years ago - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl Shutsemau) Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail pages encode their relationship to the head page - "mm/damon/core: improve DAMOS quota efficiency for core layer filters" (SeongJae Park) Improve two problematic behaviors of DAMOS that makes it less efficient when core layer filters are used - "mm/damon: strictly respect min_nr_regions" (SeongJae Park) Improve DAMON usability by extending the treatment of the min_nr_regions user-settable parameter - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka) The proper fix for a previously hotfixed SMP=n issue. Code simplifications and cleanups ensued - "mm: cleanups around unmapping / zapping" (David Hildenbrand) A bunch of cleanups around unmapping and zapping. Mostly simplifications, code movements, documentation and renaming of zapping functions - "support batched checking of the young flag for MGLRU" (Baolin Wang) Batched checking of the young flag for MGLRU. It's part cleanups; one benchmark shows large performance benefits for arm64 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner) memcg cleanup and robustness improvements - "Allow order zero pages in page reporting" (Yuvraj Sakshith) Enhance free page reporting - it is presently and undesirably order-0 pages when reporting free memory. - "mm: vma flag tweaks" (Lorenzo Stoakes) Cleanup work following from the recent conversion of the VMA flags to a bitmap - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae Park) Add some more developer-facing debug checks into DAMON core - "mm/damon: test and document power-of-2 min_region_sz requirement" (SeongJae Park) An additional DAMON kunit test and makes some adjustments to the addr_unit parameter handling - "mm/damon/core: make passed_sample_intervals comparisons overflow-safe" (SeongJae Park) Fix a hard-to-hit time overflow issue in DAMON core - "mm/damon: improve/fixup/update ratio calculation, test and documentation" (SeongJae Park) A batch of misc/minor improvements and fixups for DAMON - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David Hildenbrand) Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code movement was required. - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky) A somewhat random mix of fixups, recompression cleanups and improvements in the zram code - "mm/damon: support multiple goal-based quota tuning algorithms" (SeongJae Park) Extend DAMOS quotas goal auto-tuning to support multiple tuning algorithms that users can select - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao) Fix the khugpaged sysfs handling so we no longer spam the logs with reams of junk when starting/stopping khugepaged - "mm: improve map count checks" (Lorenzo Stoakes) Provide some cleanups and slight fixes in the mremap, mmap and vma code - "mm/damon: support addr_unit on default monitoring targets for modules" (SeongJae Park) Extend the use of DAMON core's addr_unit tunable - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache) Cleanups to khugepaged and is a base for Nico's planned khugepaged mTHP support - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand) Code movement and cleanups in the memhotplug and sparsemem code - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION" (David Hildenbrand) Rationalize some memhotplug Kconfig support - "change young flag check functions to return bool" (Baolin Wang) Cleanups to change all young flag check functions to return bool - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh Law and SeongJae Park) Fix a few potential DAMON bugs - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo Stoakes) Convert a lot of the existing use of the legacy vm_flags_t data type to the new vma_flags_t type which replaces it. Mainly in the vma code. - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes) Expand the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. Cleanups, documentation, extension of mmap_prepare into filesystem drivers - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes) Simplify and clean up zap_huge_pmd(). Additional cleanups around vm_normal_folio_pmd() and the softleaf functionality are performed. * tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm: fix deferred split queue races during migration mm/khugepaged: fix issue with tracking lock mm/huge_memory: add and use has_deposited_pgtable() mm/huge_memory: add and use normal_or_softleaf_folio_pmd() mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio() mm/huge_memory: separate out the folio part of zap_huge_pmd() mm/huge_memory: use mm instead of tlb->mm mm/huge_memory: remove unnecessary sanity checks mm/huge_memory: deduplicate zap deposited table call mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE() mm/huge_memory: add a common exit path to zap_huge_pmd() mm/huge_memory: handle buggy PMD entry in zap_huge_pmd() mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc mm/huge: avoid big else branch in zap_huge_pmd() mm/huge_memory: simplify vma_is_specal_huge() mm: on remap assert that input range within the proposed VMA mm: add mmap_action_map_kernel_pages[_full]() uio: replace deprecated mmap hook with mmap_prepare in uio_info drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare mm: allow handling of stacked mmap_prepare hooks in more drivers ...

tracing: add __event_in_*irq() helpers

2026-04-05T20:53:04+00:00

Patch series "mm: vmscan: add PID and cgroup ID to vmscan tracepoints", v8. This patch (of 3): Some trace events want to expose in their output if they were triggered in an interrupt or softirq context. Instead of recording this in the event structure itself, as this information is stored in the flags portion of the event header, add helper macros that can be used in the print format: TP_printk("val=%d %s", __entry->val, __event_in_irq() ? "(in-irq)" : "") This will output "(in-irq)" for the event in the trace data if the event was triggered in hard or soft interrupt context. Link: https://lkml.kernel.org/r/20260316160908.42727-1-tballasi@linux.microsoft.com Link: https://lore.kernel.org/all/20251229132942.31a2b583@gandalf.local.home/ Link: https://lkml.kernel.org/r/20260316160908.42727-2-tballasi@linux.microsoft.com Signed-off-by: Steven Rostedt (Google) Signed-off-by: Thomas Ballasi Reviewed-by: Shakeel Butt Cc: Axel Rasmussen Cc: David Hildenbrand Cc: Johannes Weiner Cc: Lorenzo Stoakes Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Qi Zheng Cc: Wei Xu Cc: Yuanchu Xie Signed-off-by: Andrew Morton

tracing: Use explicit array size instead of sentinel elements in symbol printing

2026-03-12T11:15:53+00:00

The sentinel value added by the wrapper macros __print_symbolic() et al prevents the callers from adding their own trailing comma. This makes constructing symbol list dynamically based on kconfig values tedious. Drop the sentinel elements, so callers can either specify the trailing comma or not, just like in regular array initializers. Signed-off-by: Thomas Weißschuh (Schneider Electric) Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260311-hrtimer-cleanups-v1-2-095357392669@linutronix.de

tracing: Add bitmask-list option for human-readable bitmask display

2026-01-26T22:00:50+00:00

Add support for displaying bitmasks in human-readable list format (e.g., 0,2-5,7) in addition to the default hexadecimal bitmap representation. This is particularly useful when tracing CPU masks and other large bitmasks where individual bit positions are more meaningful than their hexadecimal encoding. When the "bitmask-list" option is enabled, the printk "%*pbl" format specifier is used to render bitmasks as comma-separated ranges, making trace output easier to interpret for complex CPU configurations and large bitmask values. Link: https://patch.msgid.link/20251226160724.2246493-2-atomlin@atomlin.com Signed-off-by: Aaron Tomlin Signed-off-by: Steven Rostedt (Google)

tracing: Add __print_dynamic_array() helper

2024-10-30T16:24:32+00:00

When printing a dynamic array in a trace event, the method is rather ugly. It has the format of: __print_array(__get_dynamic_array(array), __get_dynmaic_array_len(array) / el_size, el_size) Since dynamic arrays are known to the tracing infrastructure, create a helper macro that does the above for you. __print_dynamic_array(array, el_size) Which would expand to the same output. Signed-off-by: Steven Rostedt (Google) Signed-off-by: Avadhut Naik Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Qiuxu Zhuo Link: https://lore.kernel.org/r/20241022194158.110073-3-avadhut.naik@amd.com

tracing/treewide: Remove second parameter of __assign_str()

2024-05-23T00:14:47+00:00

With the rework of how the __string() handles dynamic strings where it saves off the source string in field in the helper structure[1], the assignment of that value to the trace event field is stored in the helper value and does not need to be passed in again. This means that with: __string(field, mystring) Which use to be assigned with __assign_str(field, mystring), no longer needs the second parameter and it is unused. With this, __assign_str() will now only get a single parameter. There's over 700 users of __assign_str() and because coccinelle does not handle the TRACE_EVENT() macro I ended up using the following sed script: git grep -l __assign_str | while read a ; do sed -e 's/$__assign_str([^,]*[^ ,]$ *,[^;]*/\1)/' $a > /tmp/test-file; mv /tmp/test-file $a; done I then searched for __assign_str() that did not end with ';' as those were multi line assignments that the sed script above would fail to catch. Note, the same updates will need to be done for: __assign_str_len() __assign_rel_str() __assign_rel_str_len() I tested this with both an allmodconfig and an allyesconfig (build only for both). [1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/ Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Linus Torvalds Cc: Julia Lawall Signed-off-by: Steven Rostedt (Google) Acked-by: Jani Nikula Acked-by: Christian König for the amdgpu parts. Acked-by: Thomas Hellström #for Acked-by: Rafael J. Wysocki # for thermal Acked-by: Takashi Iwai Acked-by: Darrick J. Wong # xfs Tested-by: Guenter Roeck

tracing: Just use strcmp() for testing string() and assign_str() match

2024-03-19T18:23:30+00:00

As __assign_str() no longer uses its "src" parameter, there's a check to make sure nothing depends on it being different than what was passed to __string(). It originally just compared the pointer passed to __string() with the pointer passed into __assign_str() via the "src" parameter. But there's a couple of outliers that just pass in a quoted string constant, where comparing the pointers is UB to the compiler, as the compiler is free to create multiple copies of the same string constant. Instead, just use strcmp(). It may slow down the trace event, but this will eventually be removed. Also, fix the issue of passing NULL to strcmp() by adding a WARN_ON() to make sure that both "src" and the pointer saved in __string() are either both NULL or have content, and then checking if "src" is not NULL before performing the strcmp(). Link: https://lore.kernel.org/all/CAHk-=wjxX16kWd=uxG5wzqt=aXoYDf1BgWOKk+qVmAO0zh7sjA@mail.gmail.com/ Fixes: b1afefa62ca9 ("tracing: Use strcmp() in __assign_str() WARN_ON() check") Reported-by: Linus Torvalds Signed-off-by: Steven Rostedt (Google) Signed-off-by: Linus Torvalds

tracing: Add __string_src() helper to help compilers not to get confused

2024-03-18T14:33:06+00:00

The __string() helper macro of the TRACE_EVENT() macro is used to determine how much of the ring buffer needs to be allocated to fit the given source string. Some trace events have a string that is dependent on another variable that could be NULL, and in those cases the string is passed in to be NULL. The __string() macro can handle being passed in a NULL pointer for which it will turn it into "(null)". It does that with: strlen((src) ? (const char *)(src) : "(null)") + 1 But if src itself has the same conditional type it can confuse the compiler. That is: __string(r ? dev(r)->name : NULL) Would turn into: strlen((r ? dev(r)->name : NULL) ? (r ? dev(r)->name : NULL) : "(null)" + 1 For which the compiler thinks that NULL is being passed to strlen() and gives this kind of warning: ./include/trace/stages/stage5_get_offsets.h:50:21: warning: argument 1 null where non-null expected [-Wnonnull] 50 | strlen((src) ? (const char *)(src) : "(null)") + 1) Instead, create a static inline function that takes the src string and will return the string if it is not NULL and will return "(null)" if it is. This will then make the strlen() line: strlen(__string_src(src)) + 1 Where the compiler can see that strlen() will not end up with NULL and does not warn about it. Note that this depends on commit 51270d573a8d ("tracing/net_sched: Fix tracepoints that save qdisc_dev() as a string") being applied, as passing the qdisc_dev() into __string_src() will give an error. Link: https://lore.kernel.org/all/ZfNmfCmgCs4Nc+EH@aschofie-mobl2/ Link: https://lore.kernel.org/linux-trace-kernel/20240314232754.345cea82@rorschach.local.home Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Reported-by: Alison Schofield Signed-off-by: Steven Rostedt (Google)

tracing: Use strcmp() in __assign_str() WARN_ON() check

2024-03-18T14:33:06+00:00

The WARN_ON() check in __assign_str() to catch where the source variable to the macro doesn't match the source variable to __string() gives an error in clang: >> include/trace/events/sunrpc.h:703:4: warning: result of comparison against a string literal is unspecified (use an explicit string comparison function instead) [-Wstring-compare] 670 | __assign_str(progname, "unknown"); That's because the __assign_str() macro has: WARN_ON_ONCE((src) != __data_offsets.dst##_ptr_); Where "src" is a string literal. Clang warns when comparing a string literal directly as it is undefined to what the value of the literal is. Since this is still to make sure the same string that goes to __string() is the same as __assign_str(), for string literals do a test for that and then use strcmp() in those cases Note that this depends on commit 51270d573a8d ("tracing/net_sched: Fix tracepoints that save qdisc_dev() as a string") being applied, as this was what found that bug. Link: https://lore.kernel.org/linux-trace-kernel/20240312113002.00031668@gandalf.local.home Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Nathan Chancellor Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202402292111.KIdExylU-lkp@intel.com/ Fixes: 433e1d88a3be ("tracing: Add warning if string in __assign_str() does not match __string()") Signed-off-by: Steven Rostedt (Google)

tracing: Remove second parameter to __assign_rel_str()

2024-03-18T14:33:05+00:00

The second parameter of __assign_rel_str() is no longer used. It can be removed. Note, the only real users of rel_string is user events. This code is just in the sample code for testing purposes. This makes __assign_rel_str() different than __assign_str() but that's fine. __assign_str() is used over 700 places and has a larger impact. That change will come later. Link: https://lore.kernel.org/linux-trace-kernel/20240223162519.2beb8112@gandalf.local.home Cc: Mathieu Desnoyers Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google)

kernel/linux.git/include/trace/stages, branch master

Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

tracing: add __event_in_*irq() helpers

tracing: Use explicit array size instead of sentinel elements in symbol printing

tracing: Add bitmask-list option for human-readable bitmask display

tracing: Add __print_dynamic_array() helper

tracing/treewide: Remove second parameter of __assign_str()

tracing: Just use strcmp() for testing __string() and __assign_str() match

tracing: Add __string_src() helper to help compilers not to get confused

tracing: Use strcmp() in __assign_str() WARN_ON() check

tracing: Remove second parameter to __assign_rel_str()

tracing: Just use strcmp() for testing string() and assign_str() match