mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-12-27 14:41:22 -05:00
02baaa67d9
Pull sched_ext updates from Tejun Heo: - Improve recovery from misbehaving BPF schedulers. When a scheduler puts many tasks with varying affinity restrictions on a shared DSQ, CPUs scanning through tasks they cannot run can overwhelm the system, causing lockups. Bypass mode now uses per-CPU DSQs with a load balancer to avoid this, and hooks into the hardlockup detector to attempt recovery. Add scx_cpu0 example scheduler to demonstrate this scenario. - Add lockless peek operation for DSQs to reduce lock contention for schedulers that need to query queue state during load balancing. - Allow scx_bpf_reenqueue_local() to be called from anywhere in preparation for deprecating cpu_acquire/release() callbacks in favor of generic BPF hooks. - Prepare for hierarchical scheduler support: add scx_bpf_task_set_slice() and scx_bpf_task_set_dsq_vtime() kfuncs, make scx_bpf_dsq_insert*() return bool, and wrap kfunc args in structs for future aux__prog parameter. - Implement cgroup_set_idle() callback to notify BPF schedulers when a cgroup's idle state changes. - Fix migration tasks being incorrectly downgraded from stop_sched_class to rt_sched_class across sched_ext enable/disable. Applied late as the fix is low risk and the bug subtle but needs stable backporting. - Various fixes and cleanups including cgroup exit ordering, SCX_KICK_WAIT reliability, and backward compatibility improvements. * tag 'sched_ext-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (44 commits) sched_ext: Fix incorrect sched_class settings for per-cpu migration tasks sched_ext: tools: Removing duplicate targets during non-cross compilation sched_ext: Use kvfree_rcu() to release per-cpu ksyncs object sched_ext: Pass locked CPU parameter to scx_hardlockup() and add docs sched_ext: Update comments replacing breather with aborting mechanism sched_ext: Implement load balancer for bypass mode sched_ext: Factor out abbreviated dispatch dequeue into dispatch_dequeue_locked() sched_ext: Factor out scx_dsq_list_node cursor initialization into INIT_DSQ_LIST_CURSOR sched_ext: Add scx_cpu0 example scheduler sched_ext: Hook up hardlockup detector sched_ext: Make handle_lockup() propagate scx_verror() result sched_ext: Refactor lockup handlers into handle_lockup() sched_ext: Make scx_exit() and scx_vexit() return bool sched_ext: Exit dispatch and move operations immediately when aborting sched_ext: Simplify breather mechanism with scx_aborting flag sched_ext: Use per-CPU DSQs instead of per-node global DSQs in bypass mode sched_ext: Refactor do_enqueue_task() local and global DSQ paths sched_ext: Use shorter slice in bypass mode sched_ext: Mark racy bitfields to prevent adding fields that can't tolerate races sched_ext: Minor cleanups to scx_task_iter ...
Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. Quick Start ----------- * Report a bug: See Documentation/admin-guide/reporting-issues.rst * Get the latest kernel: https://kernel.org * Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst * Join the community: https://lore.kernel.org/ Essential Documentation ----------------------- All users should be familiar with: * Building requirements: Documentation/process/changes.rst * Code of Conduct: Documentation/process/code-of-conduct.rst * License: See COPYING Documentation can be built with make htmldocs or viewed online at: https://www.kernel.org/doc/html/latest/ Who Are You? ============ Find your role below: * New Kernel Developer - Getting started with kernel development * Academic Researcher - Studying kernel internals and architecture * Security Expert - Hardening and vulnerability analysis * Backport/Maintenance Engineer - Maintaining stable kernels * System Administrator - Configuring and troubleshooting * Maintainer - Leading subsystems and reviewing patches * Hardware Vendor - Writing drivers for new hardware * Distribution Maintainer - Packaging kernels for distros For Specific Users ================== New Kernel Developer -------------------- Welcome! Start your kernel development journey here: * Getting Started: Documentation/process/development-process.rst * Your First Patch: Documentation/process/submitting-patches.rst * Coding Style: Documentation/process/coding-style.rst * Build System: Documentation/kbuild/index.rst * Development Tools: Documentation/dev-tools/index.rst * Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst * Core APIs: Documentation/core-api/index.rst Academic Researcher ------------------- Explore the kernel's architecture and internals: * Researcher Guidelines: Documentation/process/researcher-guidelines.rst * Memory Management: Documentation/mm/index.rst * Scheduler: Documentation/scheduler/index.rst * Networking Stack: Documentation/networking/index.rst * Filesystems: Documentation/filesystems/index.rst * RCU (Read-Copy Update): Documentation/RCU/index.rst * Locking Primitives: Documentation/locking/index.rst * Power Management: Documentation/power/index.rst Security Expert --------------- Security documentation and hardening guides: * Security Documentation: Documentation/security/index.rst * LSM Development: Documentation/security/lsm-development.rst * Self Protection: Documentation/security/self-protection.rst * Reporting Vulnerabilities: Documentation/process/security-bugs.rst * CVE Procedures: Documentation/process/cve.rst * Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst * Security Features: Documentation/userspace-api/seccomp_filter.rst Backport/Maintenance Engineer ----------------------------- Maintain and stabilize kernel versions: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * Backporting Guide: Documentation/process/backporting.rst * Applying Patches: Documentation/process/applying-patches.rst * Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git for Maintainers: Documentation/maintainer/configure-git.rst System Administrator -------------------- Configure, tune, and troubleshoot Linux systems: * Admin Guide: Documentation/admin-guide/index.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst * Tracing/Debugging: Documentation/trace/index.rst * Performance Security: Documentation/admin-guide/perf-security.rst * Hardware Monitoring: Documentation/hwmon/index.rst Maintainer ---------- Lead kernel subsystems and manage contributions: * Maintainer Handbook: Documentation/maintainer/index.rst * Pull Requests: Documentation/maintainer/pull-requests.rst * Managing Patches: Documentation/maintainer/modifying-patches.rst * Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst * Development Process: Documentation/process/maintainer-handbooks.rst * Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git Configuration: Documentation/maintainer/configure-git.rst Hardware Vendor --------------- Write drivers and support new hardware: * Driver API Guide: Documentation/driver-api/index.rst * Driver Model: Documentation/driver-api/driver-model/driver.rst * Device Drivers: Documentation/driver-api/infrastructure.rst * Bus Types: Documentation/driver-api/driver-model/bus.rst * Device Tree Bindings: Documentation/devicetree/bindings/ * Power Management: Documentation/driver-api/pm/index.rst * DMA API: Documentation/core-api/dma-api.rst Distribution Maintainer ----------------------- Package and distribute the kernel: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * ABI Documentation: Documentation/ABI/README * Kernel Configuration: Documentation/kbuild/kconfig.rst * Module Signing: Documentation/admin-guide/module-signing.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst Communication and Support ========================= * Mailing Lists: https://lore.kernel.org/ * IRC: #kernelnewbies on irc.oftc.net * Bugzilla: https://bugzilla.kernel.org/ * MAINTAINERS file: Lists subsystem maintainers and mailing lists * Email Clients: Documentation/process/email-clients.rst