Changes in Makefile

7393febcb1b2082c0484952729cbebfe4dc508d5 - Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Tue, 14 Apr 2026 21:36:25 +0200

Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipPull locking updates from Ingo Molnar: "Mutexes: - Add killable flavor to guard definitions (Davidlohr Bueso) - Remove the list_head from struct mutex (Matthew Wilcox) - Rename mutex_init_lockep() (Davidlohr Bueso) rwsems: - Remove the list_head from struct rw_semaphore and replace it with a single pointer (Matthew Wilcox) - Fix logic error in rwsem_del_waiter() (Andrei Vagin) Semaphores: - Remove the list_head from struct semaphore (Matthew Wilcox) Jump labels: - Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh) - Remove workaround for old compilers in initializations (Thomas Weißschuh) Lock context analysis changes and improvements: - Add context analysis for rwsems (Peter Zijlstra) - Fix rwlock and spinlock lock context annotations (Bart Van Assche) - Fix rwlock support in (Bart Van Assche) - Add lock context annotations in the spinlock implementation (Bart Van Assche) - signal: Fix the lock_task_sighand() annotation (Bart Van Assche) - ww-mutex: Fix the ww_acquire_ctx function annotations (Bart Van Assche) - Add lock context support in do_raw_{read,write}_trylock() (Bart Van Assche) - arm64, compiler-context-analysis: Permit alias analysis through __READ_ONCE() with CONFIG_LTO=y (Marco Elver) - Add __cond_releases() (Peter Zijlstra) - Add context analysis for mutexes (Peter Zijlstra) - Add context analysis for rtmutexes (Peter Zijlstra) - Convert futexes to compiler context analysis (Peter Zijlstra) Rust integration updates: - Add atomic fetch_sub() implementation (Andreas Hindborg) - Refactor various rust_helper_ methods for expansion (Boqun Feng) - Add Atomic<*{mut,const} T> support (Boqun Feng) - Add atomic operation helpers over raw pointers (Boqun Feng) - Add performance-optimal Flag type for atomic booleans, to avoid slow byte-sized RMWs on architectures that don't support them. (FUJITA Tomonori) - Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA Tomonori) LTO support updates: - arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver) - compiler: Simplify generic RELOC_HIDE() (Marco Elver) Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap, Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) compiler: Simplify generic RELOC_HIDE() locking: Add lock context annotations in the spinlock implementation locking: Add lock context support in do_raw_{read,write}_trylock() locking: Fix rwlock support in lockdep: Raise default stack trace limits when KASAN is enabled cleanup: Optimize guards jump_label: remove workaround for old compilers in initializations jump_label: use ATOMIC_INIT() for initialization of .enabled futex: Convert to compiler context analysis locking/rwsem: Fix logic error in rwsem_del_waiter() locking/rwsem: Add context analysis locking/rtmutex: Add context analysis locking/mutex: Add context analysis compiler-context-analysys: Add __cond_releases() locking/mutex: Remove the list_head from struct mutex locking/semaphore: Remove the list_head from struct semaphore locking/rwsem: Remove the list_head from struct rw_semaphore rust: atomic: Update a safety comment in impl of `fetch_add()` rust: sync: atomic: Update documentation for `fetch_add()` rust: sync: atomic: Add fetch_sub() ... List of files: /linux/kernel/locking/Makefile

739690915ce1f017223ef4e6f3cc966ccfa3c861 - locking/rwsem: Add context analysis

Fri, 06 Mar 2026 10:43:56 +0100

locking/rwsem: Add context analysisAdd compiler context analysis annotations.Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20260306101417.GT1282955@noisy.programming.kicks-ass.net List of files: /linux/kernel/locking/Makefile

90bb681dcdf7e69c90b56a18f06c0389a0810b92 - locking/rtmutex: Add context analysis

Tue, 20 Jan 2026 18:17:50 +0100

locking/rtmutex: Add context analysisAdd compiler context analysis annotations.Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20260121111213.851599178@infradead.org List of files: /linux/kernel/locking/Makefile

5c4326231cde36fd5e90c41e403df9fac6238f4b - locking/mutex: Add context analysis

Tue, 20 Jan 2026 10:06:08 +0100

locking/mutex: Add context analysisAdd compiler context analysis annotations.Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/20260121111213.745353747@infradead.org List of files: /linux/kernel/locking/Makefile

bbfd5594756011167b8f8de9a00e0c946afda1e6 - Merge drm/drm-next into drm-intel-gt-next

Wed, 28 May 2025 09:20:17 +0200

Merge drm/drm-next into drm-intel-gt-nextNeed to pull in a67221b5eb8d ("drm/i915/dp: Return min bpc supported by source instead of 0")in order to fix build breakage on GCC 9.4.0 (from Ubuntu 20.04).Signed-off-by: Joonas Lahtinen List of files: /linux/kernel/locking/Makefile

db5302ae571beec635c1a96e7f72926a4e65195e - Merge drm/drm-next into drm-intel-next

Fri, 16 May 2025 09:22:36 +0200

Merge drm/drm-next into drm-intel-nextBackmerge to sync with v6.15-rc, xe, and specifically async flip changesin drm-misc.Signed-off-by: Jani Nikula List of files: /linux/kernel/locking/Makefile

4f9786035f9e519db41375818e1d0b5f20da2f10 - Merge branch 'next' into for-linus

Mon, 02 Jun 2025 06:41:07 +0200

Merge branch 'next' into for-linusPrepare input updates for 6.16 merge window. List of files: /linux/kernel/locking/Makefile

d51b9d81f7883f526b26e3ab903e646274aebeb1 - Merge tag 'v6.15-rc6' into next

Fri, 16 May 2025 01:20:39 +0200

Merge tag 'v6.15-rc6' into nextSync up with mainline to bring in xpad controller changes. List of files: /linux/kernel/locking/Makefile

844e31bbaef7c8a6ff2c0fbac45c0c85b5484482 - Merge remote-tracking branch 'drm-misc/drm-misc-next' into msm-next

Tue, 29 Apr 2025 22:42:29 +0200

Merge remote-tracking branch 'drm-misc/drm-misc-next' into msm-nextMerge drm-misc-next to get commit Fixes: fec450ca15af ("drm/display:hdmi: provide central data authority for ACR params").Signed-off-by: Rob Clark List of files: /linux/kernel/locking/Makefile

3ab7ae8e07f888f223027f0ef84d33e43919ad55 - Merge drm/drm-next into drm-xe-next

Thu, 24 Apr 2025 13:34:55 +0200

Merge drm/drm-next into drm-xe-nextBackmerge to bring in linux 6.15-rc.Signed-off-by: Thomas Hellström List of files: /linux/kernel/locking/Makefile

1afba39f9305fe4061a4e70baa6ebab9d41459da - Merge drm/drm-next into drm-misc-next

Mon, 07 Apr 2025 13:47:40 +0200

Merge drm/drm-next into drm-misc-nextBackmerging to get v6.15-rc1 into drm-misc-next. Also fixes abuild issue when enabling CONFIG_DRM_SCHED_KUNIT_TEST.Signed-off-by: Thomas Zimmermann List of files: /linux/kernel/locking/Makefile

1260ed77798502de9c98020040d2995008de10cc - Merge drm/drm-fixes into drm-misc-fixes

Tue, 08 Apr 2025 10:15:47 +0200

Merge drm/drm-fixes into drm-misc-fixesBackmerging to get updates from v6.15-rc1.Signed-off-by: Thomas Zimmermann List of files: /linux/kernel/locking/Makefile

2487b6b9bf2874cfca7efb59c95650c5b1d88d43 - Merge branch 'linus' into x86/urgent, to pick up fixes and refresh the branch

Tue, 25 Mar 2025 08:17:25 +0100

Merge branch 'linus' into x86/urgent, to pick up fixes and refresh the branchSigned-off-by: Ingo Molnar List of files: /linux/kernel/locking/Makefile

23608993bb224968a17d6db0df435ddb8e77412b - Merge tag 'locking-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Tue, 25 Mar 2025 04:55:03 +0100

Merge tag 'locking-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipPull locking updates from Ingo Molnar: "Locking primitives: - Micro-optimize percpu_{,try_}cmpxchg{64,128}_op() and {,try_}cmpxchg{64,128} on x86 (Uros Bizjak) - mutexes: extend debug checks in mutex_lock() (Yunhui Cui) - Misc cleanups (Uros Bizjak) Lockdep: - Fix might_fault() lockdep check of current->mm->mmap_lock (Peter Zijlstra) - Don't disable interrupts on RT in disable_irq_nosync_lockdep.*() (Sebastian Andrzej Siewior) - Disable KASAN instrumentation of lockdep.c (Waiman Long) - Add kasan_check_byte() check in lock_acquire() (Waiman Long) - Misc cleanups (Sebastian Andrzej Siewior) Rust runtime integration: - Use Pin for all LockClassKey usages (Mitchell Levy) - sync: Add accessor for the lock behind a given guard (Alice Ryhl) - sync: condvar: Add wait_interruptible_freezable() (Alice Ryhl) - sync: lock: Add an example for Guard:: Lock_ref() (Boqun Feng) Split-lock detection feature (x86): - Fix warning mode with disabled mitigation mode (Maksim Davydov) Locking events: - Add locking events for rtmutex slow paths (Waiman Long) - Add locking events for lockdep (Waiman Long)"* tag 'locking-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lockdep: Remove disable_irq_lockdep() lockdep: Don't disable interrupts on RT in disable_irq_nosync_lockdep.*() rust: lockdep: Use Pin for all LockClassKey usages rust: sync: condvar: Add wait_interruptible_freezable() rust: sync: lock: Add an example for Guard:: Lock_ref() rust: sync: Add accessor for the lock behind a given guard locking/lockdep: Add kasan_check_byte() check in lock_acquire() locking/lockdep: Disable KASAN instrumentation of lockdep.c locking/lock_events: Add locking events for lockdep locking/lock_events: Add locking events for rtmutex slow paths x86/split_lock: Fix the delayed detection logic lockdep/mm: Fix might_fault() lockdep check of current->mm->mmap_lock x86/locking: Remove semicolon from "lock" prefix locking/mutex: Add MUTEX_WARN_ON() into fast path x86/locking: Use asm_inline for {,try_}cmpxchg{64,128} emulations x86/locking: Use ALT_OUTPUT_SP() for percpu_{,try_}cmpxchg{64,128}_op() List of files: /linux/kernel/locking/Makefile

ee57ab5a32129f599ee1d358548dbebcb5e45953 - locking/lockdep: Disable KASAN instrumentation of lockdep.c

Sat, 08 Mar 2025 00:26:55 +0100

locking/lockdep: Disable KASAN instrumentation of lockdep.cBoth KASAN and LOCKDEP are commonly enabled in building a debug kernel.Each of them can significantly slow down the speed of a debug kernel.Enabling KASAN instrumentation of the LOCKDEP code will further slowthings down.Since LOCKDEP is a high overhead debugging tool, it will never getenabled in a production kernel. The LOCKDEP code is also pretty matureand is unlikely to get major changes. There is also a possibility ofrecursion similar to KCSAN.To evaluate the performance impact of disabling KASAN instrumentationof lockdep.c, the time to do a parallel build of the Linux defconfigkernel was used as the benchmark. Two x86-64 systems (Skylake & Zen 2)and an arm64 system were used as test beds. Two sets of non-RT and RTkernels with similar configurations except mainly CONFIG_PREEMPT_RTwere used for evaluation.For the Skylake system: Kernel Run time Sys time ------ -------- -------- Non-debug kernel (baseline) 0m47.642s 4m19.811s [CONFIG_KASAN_INLINE=y] Debug kernel 2m11.108s (x2.8) 38m20.467s (x8.9) Debug kernel (patched) 1m49.602s (x2.3) 31m28.501s (x7.3) Debug kernel (patched + mitigations=off) 1m30.988s (x1.9) 26m41.993s (x6.2) RT kernel (baseline) 0m54.871s 7m15.340s [CONFIG_KASAN_INLINE=n] RT debug kernel 6m07.151s (x6.7) 135m47.428s (x18.7) RT debug kernel (patched) 3m42.434s (x4.1) 74m51.636s (x10.3) RT debug kernel (patched + mitigations=off) 2m40.383s (x2.9) 57m54.369s (x8.0) [CONFIG_KASAN_INLINE=y] RT debug kernel 3m22.155s (x3.7) 77m53.018s (x10.7) RT debug kernel (patched) 2m36.700s (x2.9) 54m31.195s (x7.5) RT debug kernel (patched + mitigations=off) 2m06.110s (x2.3) 45m49.493s (x6.3)For the Zen 2 system: Kernel Run time Sys time ------ -------- -------- Non-debug kernel (baseline) 1m42.806s 39m48.714s [CONFIG_KASAN_INLINE=y] Debug kernel 4m04.524s (x2.4) 125m35.904s (x3.2) Debug kernel (patched) 3m56.241s (x2.3) 127m22.378s (x3.2) Debug kernel (patched + mitigations=off) 2m38.157s (x1.5) 92m35.680s (x2.3) RT kernel (baseline) 1m51.500s 14m56.322s [CONFIG_KASAN_INLINE=n] RT debug kernel 16m04.962s (x8.7) 244m36.463s (x16.4) RT debug kernel (patched) 9m09.073s (x4.9) 129m28.439s (x8.7) RT debug kernel (patched + mitigations=off) 3m31.662s (x1.9) 51m01.391s (x3.4)For the arm64 system: Kernel Run time Sys time ------ -------- -------- Non-debug kernel (baseline) 1m56.844s 8m47.150s Debug kernel 3m54.774s (x2.0) 92m30.098s (x10.5) Debug kernel (patched) 3m32.429s (x1.8) 77m40.779s (x8.8) RT kernel (baseline) 4m01.641s 18m16.777s [CONFIG_KASAN_INLINE=n] RT debug kernel 19m32.977s (x4.9) 304m23.965s (x16.7) RT debug kernel (patched) 16m28.354s (x4.1) 234m18.149s (x12.8)Turning the mitigations off doesn't seems to have any noticeable impacton the performance of the arm64 system. So the mitigation=off entriesaren't included.For the x86 CPUs, CPU mitigations has a much biggerimpact on performance, especially the RT debug kernel withCONFIG_KASAN_INLINE=n. The SRSO mitigation in Zen 2 has an especiallybig impact on the debug kernel. It is also the majority of the slowdownwith mitigations on. It is because the patched RET instruction slowsdown function returns. A lot of helper functions that are normallycompiled out or inlined may become real function calls in the debugkernel.With !CONFIG_KASAN_INLINE, the KASAN instrumentation inserts alot of __asan_loadX*() and __kasan_check_read() function calls to memoryaccess portion of the code. The lockdep's __lock_acquire() function,for instance, has 66 __asan_loadX*() and 6 __kasan_check_read() callsadded with KASAN instrumentation. Of course, the actual numbers may varydepending on the compiler used and the exact version of the lockdep code.With the Skylake test system, the parallel kernel build times reductionof the RT debug kernel with this patch are: CONFIG_KASAN_INLINE=n: -37% CONFIG_KASAN_INLINE=y: -22%The time reduction is less with CONFIG_KASAN_INLINE=y, but it is stillsignificant.Setting CONFIG_KASAN_INLINE=y can result in a significant performanceimprovement. The major drawback is a significant increase in the sizeof kernel text. In the case of vmlinux, its text size increases from45997948 to 67606807. That is a 47% size increase (about 21 Mbytes). Thesize increase of other kernel modules should be similar.With the newly added rtmutex and lockdep lock events, the relevantevent counts for the test runs with the Skylake system were: Event type Debug kernel RT debug kernel ---------- ------------ --------------- lockdep_acquire 1,968,663,277 5,425,313,953 rtlock_slowlock - 401,701,156 rtmutex_slowlock - 139,672The __lock_acquire() calls in the RT debug kernel are x2.8 times of thenon-RT debug kernel with the same workload. Since the __lock_acquire()function is a big hitter in term of performance slowdown, this makesthe RT debug kernel much slower than the non-RT one. The average locknesting depth is likely to be higher in the RT debug kernel too leadingto longer execution time in the __lock_acquire() function.As the small advantage of enabling KASAN instrumentation to catchpotential memory access error in the lockdep debugging tool is probablynot worth the drawback of further slowing down a debug kernel, disableKASAN instrumentation in the lockdep code to allow the debug kernelsto regain some performance back, especially for the RT debug kernels.Signed-off-by: Waiman Long Signed-off-by: Boqun Feng Signed-off-by: Ingo Molnar Reviewed-by: Marco Elver Reviewed-by: Andrey Konovalov Cc: Linus Torvalds Link: https://lore.kernel.org/r/20250307232717.1759087-6-boqun.feng@gmail.com List of files: /linux/kernel/locking/Makefile

7ae9fb1b7ecbb5d85d07857943f677fd1a559b18 - Merge branch 'next' into for-linus

Tue, 21 Feb 2023 20:19:49 +0100

Merge branch 'next' into for-linusPrepare input updates for 6.3 merge window. List of files: /linux/kernel/locking/Makefile

6f84981772535e670e4e2df051a672af229b6694 - Merge drm/drm-next into drm-misc-next

Thu, 19 Jan 2023 10:56:12 +0100

Merge drm/drm-next into drm-misc-nextBackmerging into drm-misc-next to get DRM accelerator infrastructure,which is required by ipuv driver.Signed-off-by: Thomas Zimmermann List of files: /linux/kernel/locking/Makefile

407da561244b9d51e6a794d6305ba38ec2c9d907 - Merge tag 'v6.2-rc3' into next

Tue, 10 Jan 2023 05:28:19 +0100

Merge tag 'v6.2-rc3' into nextMerge with mainline to bring in timer_shutdown_sync() API. List of files: /linux/kernel/locking/Makefile

0d8eae7b124e2ddaee00f186fe922450faad0ed7 - Merge drm/drm-next into drm-intel-next

Mon, 02 Jan 2023 10:31:03 +0100

Merge drm/drm-next into drm-intel-nextSync up with v6.2-rc1.Signed-off-by: Jani Nikula List of files: /linux/kernel/locking/Makefile

b501d4dc83aa3940189b68045cadc8b3eac73988 - Merge drm/drm-next into drm-intel-gt-next

Fri, 30 Dec 2022 10:09:09 +0100

Merge drm/drm-next into drm-intel-gt-nextSync after v6.2-rc1 landed in drm-next.We need to get some dependencies in place before we can mergethe fixes series from Gwan-gyeong and Chris.References: https://lore.kernel.org/all/Y6x5JCDnh2rvh4lA@intel.com/Signed-off-by: Rodrigo Vivi List of files: /linux/kernel/locking/Makefile