kernel/linux.git/include/linux/cleanup.h, branch v6.18.21

cleanup: fix scoped_class()

2025-12-18T13:02:49+00:00

[ Upstream commit 4e97bae1b412cd6ed8053b3d8a242122952985cc ] This is a class, not a guard so why on earth is it checking for guard pointers or conditional lock acquisition? None of it makes any sense at all. I'm not sure what happened back then. Maybe I had a brief psychedelic period that I completely forgot about and spaced out into a zone where that initial macro implementation made any sense at all. Link: https://patch.msgid.link/20251103-work-creds-init_cred-v1-1-cb3ec8711a6a@kernel.org Fixes: 5c21c5f22d07 ("cleanup: add a scoped version of CLASS()") Reviewed-by: Jens Axboe Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

Merge tag 'cxl-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

2025-08-01T22:47:06+00:00

Pull CXL updates from Dave Jiang: "The most significant changes in this pull request is the series that introduces ACQUIRE() and ACQUIRE_ERR() macros to replace conditional locking and ease the pain points of scoped_cond_guard(). The series also includes follow on changes that refactor the CXL sub-system to utilize the new macros. Detail summary: - Add documentation template for CXL conventions to document CXL platform quirks - Replace mutex_lock_io() with mutex_lock() for mailbox - Add location limit for fake CFMWS range for cxl_test, ARM platform enabling - CXL documentation typo and clarity fixes - Use correct format specifier for function cxl_set_ecs_threshold() - Make cxl_bus_type constant - Introduce new helper cxl_resource_contains_addr() to check address availability - Fix wrong DPA checking for PPR operation - Remove core/acpi.c and CXL core dependency on ACPI - Introduce ACQUIRE() and ACQUIRE_ERR() for conditional locks - Add CXL updates utilizing ACQUIRE() macro to remove gotos and improve readability - Add return for the dummy version of cxl_decoder_detach() without CONFIG_CXL_REGION - CXL events updates for spec r3.2 - Fix return of __cxl_decoder_detach() error path - CXL debugfs documentation fix" * tag 'cxl-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (28 commits) Documentation/ABI/testing/debugfs-cxl: Add 'cxl' to clear_poison path cxl/region: Fix an ERR_PTR() vs NULL bug cxl/events: Trace Memory Sparing Event Record cxl/events: Add extra validity checks for CVME count in DRAM Event Record cxl/events: Add extra validity checks for corrected memory error count in General Media Event Record cxl/events: Update Common Event Record to CXL spec rev 3.2 cxl: Fix -Werror=return-type in cxl_decoder_detach() cleanup: Fix documentation build error for ACQUIRE updates cxl: Convert to ACQUIRE() for conditional rwsem locking cxl/region: Consolidate cxl_decoder_kill_region() and cxl_region_detach() cxl/region: Move ready-to-probe state check to a helper cxl/region: Split commit_store() into __commit() and queue_reset() helpers cxl/decoder: Drop pointless locking cxl/decoder: Move decoder register programming to a helper cxl/mbox: Convert poison list mutex to ACQUIRE() cleanup: Introduce ACQUIRE() and ACQUIRE_ERR() for conditional locks cxl: Remove core/acpi.c and cxl core dependency on ACPI cxl/core: Using cxl_resource_contains_addr() to check address availability cxl/edac: Fix wrong dpa checking for PPR operation cxl/core: Introduce a new helper cxl_resource_contains_addr() ...

cleanup: Fix documentation build error for ACQUIRE updates

2025-07-18T02:59:02+00:00

Stephen reports: Documentation/core-api/cleanup:7: include/linux/cleanup.h:73: ERROR: Unexpected indentation. [docutils] Documentation/core-api/cleanup:7: include/linux/cleanup.h:74: WARNING: Block quote ends without a blank line; unexpected unindent. [docutils] Which points out that the ACQUIRE() example in cleanup.h missed the "::" suffix to mark the following text as a code-block. Fixes: 857d18f23ab1 ("cleanup: Introduce ACQUIRE() and ACQUIRE_ERR() for conditional locks") Reported-by: Stephen Rothwell Closes: http://lore.kernel.org/20250717173354.34375751@canb.auug.org.au Signed-off-by: Dan Williams Acked-by: Randy Dunlap Tested-by: Randy Dunlap Link: https://patch.msgid.link/20250717163036.1275791-1-dan.j.williams@intel.com Signed-off-by: Dave Jiang

cleanup: Introduce ACQUIRE() and ACQUIRE_ERR() for conditional locks

2025-07-16T18:34:36+00:00

scoped_cond_guard(), automatic cleanup for conditional locks, has a couple pain points: * It causes existing straight-line code to be re-indented into a new bracketed scope. While this can be mitigated by a new helper function to contain the scope, that is not always a comfortable conversion. * The return code from the conditional lock is tossed in favor of a scheme to pass a 'return err;' statement to the macro. Other attempts to clean this up, to behave more like guard() [1], got hung up trying to both establish and evaluate the conditional lock in one statement. ACQUIRE() solves this by reflecting the result of the condition in the automatic variable established by the lock CLASS(). The result is separately retrieved with the ACQUIRE_ERR() helper, effectively a PTR_ERR() operation. Link: http://lore.kernel.org/all/Z1LBnX9TpZLR5Dkf@gmail.com [1] Link: http://patch.msgid.link/20250512105026.GP4439@noisy.programming.kicks-ass.net Link: http://patch.msgid.link/20250512185817.GA1808@noisy.programming.kicks-ass.net Cc: Ingo Molnar Cc: Linus Torvalds Cc: David Lechner Cc: Fabio M. De Francesco Signed-off-by: Peter Zijlstra (Intel) [djbw: wrap Peter's proposal with changelog and comments] Co-developed-by: Dan Williams Signed-off-by: Dan Williams Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20250711234932.671292-2-dan.j.williams@intel.com Signed-off-by: Dave Jiang

cleanup: add a scoped version of CLASS()

2025-07-11T14:01:07+00:00

This will make it possible to use: scoped_class() { } constructs to limit variables to certain scopes and still perform auto-cleanup. Signed-off-by: Christian Brauner

cleanup: Provide retain_and_null_ptr()

2025-04-09T18:47:29+00:00

In cases where an allocation is consumed by another function, the allocation needs to be retained on success or freed on failure. The code pattern is usually: struct foo *f = kzalloc(sizeof(*f), GFP_KERNEL); struct bar *b; ,,, // Initialize f ... if (ret) goto free; ... bar = bar_create(f); if (!bar) { ret = -ENOMEM; goto free; } ... return 0; free: kfree(f); return ret; This prevents using __free(kfree) on @f because there is no canonical way to tell the cleanup code that the allocation should not be freed. Abusing no_free_ptr() by force ignoring the return value is not really a sensible option either. Provide an explicit macro retain_and_null_ptr(), which NULLs the cleanup pointer. That makes it easy to analyze and reason about. Signed-off-by: Thomas Gleixner Reviewed-by: Jonathan Cameron Reviewed-by: James Bottomley Link: https://lore.kernel.org/all/20250319105506.083538907@linutronix.de

Revert "Merge tag 'irq-msi-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip"

2025-03-28T18:22:54+00:00

This reverts commit 36f5f026df6c1cd8a20373adc4388d2b3401ce91, reversing changes made to 43a7eec035a5b64546c8adefdc9cf96a116da14b. Thomas says: "I just noticed that for some incomprehensible reason, probably sheer incompetemce when trying to utilize b4, I managed to merge an outdated _and_ buggy version of that series. Can you please revert that merge completely?" Done. Requested-by: Thomas Gleixner Signed-off-by: Linus Torvalds

Merge tag 'timers-core-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-03-25T17:33:23+00:00

Pull timer core updates from Thomas Gleixner: - Fix a memory ordering issue in posix-timers Posix-timer lookup is lockless and reevaluates the timer validity under the timer lock, but the update which validates the timer is not protected by the timer lock. That allows the store to be reordered against the initialization stores, so that the lookup side can observe a partially initialized timer. That's mostly a theoretical problem, but incorrect nevertheless. - Fix a long standing inconsistency of the coarse time getters The coarse time getters read the base time of the current update cycle without reading the actual hardware clock. NTP frequency adjustment can set the base time backwards. The fine grained interfaces compensate this by reading the clock and applying the new conversion factor, but the coarse grained time getters use the base time directly. That allows the user to observe time going backwards. Cure it by always forwarding base time, when NTP changes the frequency with an immediate step. - Rework of posix-timer hashing The posix-timer hash is not scalable and due to the CRIU timer restore mechanism prone to massive contention on the global hash bucket lock. Replace the global hash lock with a fine grained per bucket locking scheme to address that. - Rework the proc/$PID/timers interface. /proc/$PID/timers is provided for CRIU to be able to restore a timer. The printout happens with sighand lock held and interrupts disabled. That's not required as this can be done with RCU protection as well. - Provide a sane mechanism for CRIU to restore a timer ID CRIU restores timers by creating and deleting them until the kernel internal per process ID counter reached the requested ID. That's horribly slow for sparse timer IDs. Provide a prctl() which allows CRIU to restore a timer with a given ID. When enabled the ID pointer is used as input pointer to read the requested ID from user space. When disabled, the normal allocation scheme (next ID) is active as before. This is backwards compatible for both kernel and user space. - Make hrtimer_update_function() less expensive. The sanity checks are valuable, but expensive for high frequency usage in io/uring. Make the debug checks conditional and enable them only when lockdep is enabled. - Small updates, cleanups and improvements * tag 'timers-core-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) selftests/timers: Improve skew_consistency by testing with other clockids timekeeping: Fix possible inconsistencies in _COARSE clockids posix-timers: Drop redundant memset() invocation selftests/timers/posix-timers: Add a test for exact allocation mode posix-timers: Provide a mechanism to allocate a given timer ID posix-timers: Dont iterate /proc/$PID/timers with sighand:: Siglock held posix-timers: Make per process list RCU safe posix-timers: Avoid false cacheline sharing posix-timers: Switch to jhash32() posix-timers: Improve hash table performance posix-timers: Make signal_struct:: Next_posix_timer_id an atomic_t posix-timers: Make lock_timer() use guard() posix-timers: Rework timer removal posix-timers: Simplify lock/unlock_timer() posix-timers: Use guards in a few places posix-timers: Remove SLAB_PANIC from kmem cache posix-timers: Remove a few paranoid warnings posix-timers: Cleanup includes posix-timers: Add cond_resched() to posix_timer_add() search loop posix-timers: Initialise timer before adding it to the hash table ...

Merge tag 'irq-msi-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-03-25T16:15:17+00:00

Pull MSI irq updates from Thomas Gleixner: - Switch the MSI descriptor locking to guards - Replace the broken PCI/TPH implementation, which lacks any form of serialization against concurrent modifications with a properly serialized mechanism in the PCI/MSI core code - Replace the MSI descriptor abuse in the SCSI/UFS Qualcom driver with dedicated driver internal storage * tag 'irq-msi-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/msi: Rename msi_[un]lock_descs() scsi: ufs: qcom: Remove the MSI descriptor abuse PCI/TPH: Replace the broken MSI-X control word update PCI/MSI: Provide a sane mechanism for TPH PCI: hv: Switch MSI descriptor locking to guard() PCI/MSI: Switch to MSI descriptor locking to guard() NTB/msi: Switch MSI descriptor locking to lock guard() soc: ti: ti_sci_inta_msi: Switch MSI descriptor locking to guard() genirq/msi: Use lock guards for MSI descriptor locking cleanup: Provide retain_ptr() genirq/msi: Make a few functions static

cleanup: Provide retain_ptr()

2025-03-13T17:57:59+00:00

In cases where an allocation is consumed by another function, the allocation needs to be retained on success or freed on failure. The code pattern is usually: struct foo *f = kzalloc(sizeof(*f), GFP_KERNEL); struct bar *b; ,,, // Initialize f ... if (ret) goto free; ... bar = bar_create(f); if (!bar) { ret = -ENOMEM; goto free; } ... return 0; free: kfree(f); return ret; This prevents using __free(kfree) on @f because there is no canonical way to tell the cleanup code that the allocation should not be freed. Abusing no_free_ptr() by force ignoring the return value is not really a sensible option either. Provide an explicit macro retain_ptr(), which NULLs the cleanup pointer. That makes it easy to analyze and reason about. Signed-off-by: Thomas Gleixner Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/all/20250313130321.442025758@linutronix.de