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2024-03-25Merge tag 'v6.9-rc1' into sched/core, to pick up fixes and to refresh the branchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-03-24Merge tag 'sched-urgent-2024-03-24' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler doc clarification from Thomas Gleixner: "A single update for the documentation of the base_slice_ns tunable to clarify that any value which is less than the tick slice has no effect because the scheduler tick is not guaranteed to happen within the set time slice" * tag 'sched-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/doc: Update documentation for base_slice_ns and CONFIG_HZ relation
2024-03-21sched/doc: Update documentation for base_slice_ns and CONFIG_HZ relationMukesh Kumar Chaurasiya
The tunable base_slice_ns is dependent on CONFIG_HZ (i.e. TICK_NSEC) for any significant performance improvement. The reason being the scheduler tick is not frequent enough to force preemption when base_slice expires in case of: base_slice_ns < TICK_NSEC The below data is of stress-ng: Number of CPU: 1 Stressor threads: 4 Time: 30sec On CONFIG_HZ=1000 | base_slice | avg-run (msec) | context-switches | | ---------- | -------------- | ---------------- | | 3ms | 2.914 | 10342 | | 6ms | 4.857 | 6196 | | 9ms | 6.754 | 4482 | | 12ms | 7.872 | 3802 | | 22ms | 11.294 | 2710 | | 32ms | 13.425 | 2284 | On CONFIG_HZ=100 | base_slice | avg-run (msec) | context-switches | | ---------- | -------------- | ---------------- | | 3ms | 9.144 | 3337 | | 6ms | 9.113 | 3301 | | 9ms | 8.991 | 3315 | | 12ms | 12.935 | 2328 | | 22ms | 16.031 | 1915 | | 32ms | 18.608 | 1622 | base_slice: the value of base_slice in ms avg-run (msec): average time of the stressor threads got on cpu before it got preempted context-switches: number of context switches for the stress-ng process Signed-off-by: Mukesh Kumar Chaurasiya <mchauras@linux.ibm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20240320173815.927637-2-mchauras@linux.ibm.com
2024-03-12sched/balancing: Rename load_balance() => sched_balance_rq()Ingo Molnar
Standardize scheduler load-balancing function names on the sched_balance_() prefix. Also load_balance() has become somewhat of a misnomer: historically it was the first and primary load-balancing function that was called, but with the introduction of sched domains, it's become a lower layer function that balances runqueues. Rename it to sched_balance_rq() accordingly. Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20240308111819.1101550-6-mingo@kernel.org
2024-03-12sched/balancing: Rename rebalance_domains() => sched_balance_domains()Ingo Molnar
Standardize scheduler load-balancing function names on the sched_balance_() prefix. Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20240308111819.1101550-5-mingo@kernel.org
2024-03-12sched/balancing: Rename trigger_load_balance() => sched_balance_trigger()Ingo Molnar
Standardize scheduler load-balancing function names on the sched_balance_() prefix. Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20240308111819.1101550-4-mingo@kernel.org
2024-03-12sched/balancing: Rename scheduler_tick() => sched_tick()Ingo Molnar
- Standardize on prefixing scheduler-internal functions defined in <linux/sched.h> with sched_*() prefix. scheduler_tick() was the only function using the scheduler_ prefix. Harmonize it. - The other reason to rename it is the NOHZ scheduler tick handling functions are already named sched_tick_*(). Make the 'git grep sched_tick' more meaningful. Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Valentin Schneider <vschneid@redhat.com> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20240308111819.1101550-3-mingo@kernel.org
2024-03-12sched/balancing: Rename run_rebalance_domains() => sched_balance_softirq()Ingo Molnar
run_rebalance_domains() is a misnomer, as it doesn't only run rebalance_domains(), but since the introduction of the NOHZ code it also runs nohz_idle_balance(). Rename it to sched_balance_softirq(), reflecting its more generic purpose and that it's a softirq handler. Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Valentin Schneider <vschneid@redhat.com> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20240308111819.1101550-2-mingo@kernel.org
2024-03-12sched/debug: Increase SCHEDSTAT_VERSION to 16Ingo Molnar
We changed the order of definitions within 'enum cpu_idle_type', which changed the order of [CPU_MAX_IDLE_TYPES] columns in show_schedstat(). Suggested-by: Shrikanth Hegde <sshegde@linux.ibm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: "Gautham R. Shenoy" <gautham.shenoy@amd.com> Link: https://lore.kernel.org/r/20240308105901.1096078-5-mingo@kernel.org
2024-02-15membarrier: Create Documentation/scheduler/membarrier.rstAndrea Parri
To gather the architecture requirements of the "private/global expedited" membarrier commands. The file will be expanded to integrate further information about the membarrier syscall (as needed/desired in the future). While at it, amend some related inline comments in the membarrier codebase. Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/r/20240131144936.29190-3-parri.andrea@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-23sched/fair: Remove SCHED_FEAT(UTIL_EST_FASTUP, true)Vincent Guittot
sched_feat(UTIL_EST_FASTUP) has been added to easily disable the feature in order to check for possibly related regressions. After 3 years, it has never been used and no regression has been reported. Let's remove it and make fast increase a permanent behavior. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Reviewed-by: Hongyan Xia <hongyan.xia2@arm.com> Reviewed-by: Tang Yizhou <yizhou.tang@shopee.com> Reviewed-by: Yanteng Si <siyanteng@loongson.cn> [for the Chinese translation] Reviewed-by: Alex Shi <alexs@kernel.org> Link: https://lore.kernel.org/r/20231201161652.1241695-2-vincent.guittot@linaro.org
2023-11-26sched/doc: Update documentation after renames and synchronize Chinese versionWenyu Huang
Update the documentation after these changes, which didn't entirely propagate the changes: e23edc86b09d ("sched/fair: Rename check_preempt_curr() to wakeup_preempt()") 03b7fad167ef ("sched: Add task_struct pointer to sched_class::set_curr_task") 2f88c8e802c8 ("sched/eevdf/doc: Modify the documented knob to base_slice_ns as well") [ mingo: Reworked the changelog. ] Signed-off-by: Wenyu Huang <huangwenyu5@huawei.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org
2023-11-01Merge tag 'asm-generic-6.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull ia64 removal and asm-generic updates from Arnd Bergmann: - The ia64 architecture gets its well-earned retirement as planned, now that there is one last (mostly) working release that will be maintained as an LTS kernel. - The architecture specific system call tables are updated for the added map_shadow_stack() syscall and to remove references to the long-gone sys_lookup_dcookie() syscall. * tag 'asm-generic-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: hexagon: Remove unusable symbols from the ptrace.h uapi asm-generic: Fix spelling of architecture arch: Reserve map_shadow_stack() syscall number for all architectures syscalls: Cleanup references to sys_lookup_dcookie() Documentation: Drop or replace remaining mentions of IA64 lib/raid6: Drop IA64 support Documentation: Drop IA64 from feature descriptions kernel: Drop IA64 support from sig_fault handlers arch: Remove Itanium (IA-64) architecture
2023-10-09sched/topology: Remove the EM_MAX_COMPLEXITY limitPierre Gondois
The Energy Aware Scheduler (EAS) estimates the energy consumption of placing a task on different CPUs. The goal is to minimize this energy consumption. Estimating the energy of different task placements is increasingly complex with the size of the platform. To avoid having a slow wake-up path, EAS is only enabled if this complexity is low enough. The current complexity limit was set in: b68a4c0dba3b1 ("sched/topology: Disable EAS on inappropriate platforms") ... based on the first implementation of EAS, which was re-computing the power of the whole platform for each task placement scenario, see: 390031e4c309 ("sched/fair: Introduce an energy estimation helper function") ... but the complexity of EAS was reduced in: eb92692b2544d ("sched/fair: Speed-up energy-aware wake-ups") ... and find_energy_efficient_cpu() (feec) algorithm was updated in: 3e8c6c9aac42 ("sched/fair: Remove task_util from effective utilization in feec()") find_energy_efficient_cpu() (feec) is now doing: feec() \_ for_each_pd(pd) [0] // get max_spare_cap_cpu and compute_prev_delta \_ for_each_cpu(pd) [1] \_ eenv_pd_busy_time(pd) [2] \_ for_each_cpu(pd) // compute_energy(pd) without the task \_ eenv_pd_max_util(pd, -1) [3.0] \_ for_each_cpu(pd) \_ em_cpu_energy(pd, -1) \_ for_each_ps(pd) // compute_energy(pd) with the task on prev_cpu \_ eenv_pd_max_util(pd, prev_cpu) [3.1] \_ for_each_cpu(pd) \_ em_cpu_energy(pd, prev_cpu) \_ for_each_ps(pd) // compute_energy(pd) with the task on max_spare_cap_cpu \_ eenv_pd_max_util(pd, max_spare_cap_cpu) [3.2] \_ for_each_cpu(pd) \_ em_cpu_energy(pd, max_spare_cap_cpu) \_ for_each_ps(pd) [3.1] happens only once since prev_cpu is unique. With the same definitions for nr_pd, nr_cpus and nr_ps, the complexity is of: nr_pd * (2 * [nr_cpus in pd] + 2 * ([nr_cpus in pd] + [nr_ps in pd])) + ([nr_cpus in pd] + [nr_ps in pd]) [0] * ( [1] + [2] + [3.0] + [3.2] ) + [3.1] = nr_pd * (4 * [nr_cpus in pd] + 2 * [nr_ps in pd]) + [nr_cpus in prev pd] + nr_ps The complexity limit was set to 2048 in: b68a4c0dba3b1 ("sched/topology: Disable EAS on inappropriate platforms") ... to make "EAS usable up to 16 CPUs with per-CPU DVFS and less than 8 performance states each". For the same platform, the complexity would actually be of: 16 * (4 + 2 * 7) + 1 + 7 = 296 Since the EAS complexity was greatly reduced since the limit was introduced, bigger platforms can handle EAS. For instance, a platform with 112 CPUs with 7 performance states each would not reach it: 112 * (4 + 2 * 7) + 1 + 7 = 2024 To reflect this improvement in the underlying EAS code, remove the EAS complexity check. Note that a limit on the number of CPUs still holds against EM_MAX_NUM_CPUS to avoid overflows during the energy estimation. [ mingo: Updates to the changelog. ] Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lore.kernel.org/r/20231009060037.170765-2-sshegde@linux.vnet.ibm.com
2023-10-09sched/topology: Consolidate and clean up access to a CPU's max compute capacityVincent Guittot
Remove the rq::cpu_capacity_orig field and use arch_scale_cpu_capacity() instead. The scheduler uses 3 methods to get access to a CPU's max compute capacity: - arch_scale_cpu_capacity(cpu) which is the default way to get a CPU's capacity. - cpu_capacity_orig field which is periodically updated with arch_scale_cpu_capacity(). - capacity_orig_of(cpu) which encapsulates rq->cpu_capacity_orig. There is no real need to save the value returned by arch_scale_cpu_capacity() in struct rq. arch_scale_cpu_capacity() returns: - either a per_cpu variable. - or a const value for systems which have only one capacity. Remove rq::cpu_capacity_orig and use arch_scale_cpu_capacity() everywhere. No functional changes. Some performance tests on Arm64: - small SMP device (hikey): no noticeable changes - HMP device (RB5): hackbench shows minor improvement (1-2%) - large smp (thx2): hackbench and tbench shows minor improvement (1%) Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lore.kernel.org/r/20231009103621.374412-2-vincent.guittot@linaro.org
2023-10-02sched/rt/docs: Use 'real-time' instead of 'realtime'Cyril Hrubis
Standardize on a single variant. Signed-off-by: Cyril Hrubis <chrubis@suse.cz> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20231002115553.3007-4-chrubis@suse.cz
2023-10-02sched/rt/docs: Clarify & fix sched_rt_* sysctl docsCyril Hrubis
- Describe explicitly that sched_rt_runtime_us is allocated from sched_rt_period_us and hence always less or equal to that value. - The limit for sched_rt_runtime_us is not INT_MAX-1, but rather it's limited by the value of sched_rt_period_us. If sched_rt_period_us is INT_MAX then sched_rt_runtime_us can be set to INT_MAX as well. Signed-off-by: Cyril Hrubis <chrubis@suse.cz> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20231002115553.3007-3-chrubis@suse.cz
2023-09-11Documentation: Drop or replace remaining mentions of IA64Ard Biesheuvel
Drop or update mentions of IA64, as appropriate. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-08-30Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
2023-08-24sched/eevdf/doc: Modify the documented knob to base_slice_ns as wellShrikanth Hegde
After committing the scheduler to EEVDF, we renamed the 'min_granularity_ns' sysctl to 'base_slice_ns': e4ec3318a17f ("sched/debug: Rename sysctl_sched_min_granularity to sysctl_sched_base_slice") ... but we forgot to rename it in the documentation. Do that now. Fixes: e4ec3318a17f ("sched/debug: Rename sysctl_sched_min_granularity to sysctl_sched_base_slice") Signed-off-by: Shrikanth Hegde <sshegde@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230824080342.543396-1-sshegde@linux.vnet.ibm.com
2023-08-18Documentation: Fix typosBjorn Helgaas
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-07-14docs: scheduler: completion: Fix minor error in pseudo-codeRick Wertenbroek
Add missing address-of (&) operator in pseudo-code. Signed-off-by: Rick Wertenbroek <rick.wertenbroek@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230706114057.1120335-1-rick.wertenbroek@gmail.com
2023-06-16sched/deadline: Update GRUB description in the documentationVineeth Pillai
Update the details of GRUB to reflect the updated logic. Signed-off-by: Vineeth Pillai (Google) <vineeth@bitbyteword.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@kernel.org> Acked-by: Juri Lelli <juri.lelli@redhat.com> Link: https://lore.kernel.org/r/20230530135526.2385378-2-vineeth@bitbyteword.org
2023-04-27Merge tag 'sh-for-v6.4-tag1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux Pull sh updates from John Paul Adrian Glaubitz: "This is a bit larger than my previous one and mainly consists of clean-up work in the arch/sh directory by Geert Uytterhoeven and Randy Dunlap. Additionally, this fixes a bug in the Storage Queue code that was discovered while I was reviewing a patch to switch the code to the bitmap API by Christophe Jaillet. So this contains both a fix for the original bug in the Storage Queue code that can be backported later as well as the Christophe's patch to swich the code to the bitmap API. Summary: - Use generic GCC library routines - sq: Use the bitmap API when applicable - sq: Fix incorrect element size for allocating bitmap buffer - pci: Remove unused variable in SH-7786 PCI Express code - mcount.S: fix build error when PRINTK is not enabled - remove sh5/sh64 last fragments - math-emu: fix macro redefined warning - init: use OF_EARLY_FLATTREE for early init - nmi_debug: fix return value of __setup handler - SH2007: drop the bad URL info" * tag 'sh-for-v6.4-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux: sh: Replace <uapi/asm/types.h> by <asm-generic/int-ll64.h> sh: Use generic GCC library routines sh: sq: Use the bitmap API when applicable sh: sq: Fix incorrect element size for allocating bitmap buffer sh: pci: Remove unused variable in SH-7786 PCI Express code sh: mcount.S: fix build error when PRINTK is not enabled sh: remove sh5/sh64 last fragments sh: math-emu: fix macro redefined warning sh: init: use OF_EARLY_FLATTREE for early init sh: nmi_debug: fix return value of __setup handler sh: SH2007: drop the bad URL info
2023-03-23sh: remove sh5/sh64 last fragmentsRandy Dunlap
A previous patch removed most of the sh5 (sh64) support from the kernel tree. Now remove the last stragglers. Fixes: 37744feebc08 ("sh: remove sh5 support") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Rich Felker <dalias@libc.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: linux-sh@vger.kernel.org Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Link: https://lore.kernel.org/r/20230306040037.20350-6-rdunlap@infradead.org Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
2023-03-07sched/doc: supplement CPU capacity with RISC-VSong Shuai
This commit 7d2078310cbf ("dt-bindings: arm: move cpu-capacity to a shared loation") updates some references about capacity-dmips-mhz property in this document. The list of architectures using capacity-dmips-mhz omits RISC-V, so supplements it here. Signed-off-by: Song Shuai <suagrfillet@gmail.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> # English Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Alex Shi <alexs@kernel.org> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230227105941.2749193-1-suagrfillet@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-02-25Merge tag 'riscv-for-linus-6.3-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "There's a bunch of fixes/cleanups throughout the tree as usual, but we also have a handful of new features: - Various improvements to the extension detection and alternative patching infrastructure - Zbb-optimized string routines - Support for cpu-capacity in the RISC-V DT bindings - Zicbom no longer depends on toolchain support - Some performance and code size improvements to ftrace - Support for ARCH_WANT_LD_ORPHAN_WARN - Oops now contain the faulting instruction" * tag 'riscv-for-linus-6.3-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (67 commits) RISC-V: add a spin_shadow_stack declaration riscv: mm: hugetlb: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP riscv: Add header include guards to insn.h riscv: alternative: proceed one more instruction for auipc/jalr pair riscv: Avoid enabling interrupts in die() riscv, mm: Perform BPF exhandler fixup on page fault RISC-V: take text_mutex during alternative patching riscv: hwcap: Don't alphabetize ISA extension IDs RISC-V: fix ordering of Zbb extension riscv: jump_label: Fixup unaligned arch_static_branch function RISC-V: Only provide the single-letter extensions in HWCAP riscv: mm: fix regression due to update_mmu_cache change scripts/decodecode: Add support for RISC-V riscv: Add instruction dump to RISC-V splats riscv: select ARCH_WANT_LD_ORPHAN_WARN for !XIP_KERNEL riscv: vmlinux.lds.S: explicitly catch .init.bss sections from EFI stub riscv: vmlinux.lds.S: explicitly catch .riscv.attributes sections riscv: vmlinux.lds.S: explicitly catch .rela.dyn symbols riscv: lds: define RUNTIME_DISCARD_EXIT RISC-V: move some stray __RISCV_INSN_FUNCS definitions from kprobes ...
2023-02-22Merge tag 'docs-6.3' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a moderately calm cycle for documentation; the significant changes include: - Some significant additions to the memory-management documentation - Some improvements to navigation in the HTML-rendered docs - More Spanish and Chinese translations ... and the usual set of typo fixes and such" * tag 'docs-6.3' of git://git.lwn.net/linux: (68 commits) Documentation/watchdog/hpwdt: Fix Format Documentation/watchdog/hpwdt: Fix Reference Documentation: core-api: padata: correct spelling docs/mm: Physical Memory: correct spelling in reference to CONFIG_PAGE_EXTENSION docs: Use HTML comments for the kernel-toc SPDX line docs: Add more information to the HTML sidebar Documentation: KVM: Update AMD memory encryption link printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay= Documentation: userspace-api: correct spelling Documentation: sparc: correct spelling Documentation: driver-api: correct spelling Documentation: admin-guide: correct spelling docs: add workload-tracing document to admin-guide docs/admin-guide/mm: remove useless markup docs/mm: remove useless markup docs/mm: Physical Memory: remove useless markup docs/sp_SP: Add process magic-number translation docs: ftrace: always use canonical ftrace path Doc/damon: fix the data path error dma-buf: Add "dma-buf" to title of documentation ...
2023-02-14dt-bindings: arm: move cpu-capacity to a shared loationConor Dooley
RISC-V uses the same generic topology code as arm64 & while there currently exists no binding for cpu-capacity on RISC-V, the code paths can be hit if the property is present. Move the documentation of cpu-capacity to a shared location, ahead of defining a binding for capacity-dmips-mhz on RISC-V. Update some references to this document in the process. Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Ley Foon Tan <leyfoon.tan@starfivetech.com> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Yanteng Si <siyanteng@loongson.cn> Link: https://lore.kernel.org/r/20230104180513.1379453-2-conor@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-01-24Docs/subsystem-apis: Remove '[The ]Linux' prefixes from titles of listed ↵SeongJae Park
documents Some documents that listed on subsystem-apis have 'Linux' or 'The Linux' title prefixes. It's duplicated information, and makes finding the document of interest with human eyes not easy. Remove the prefixes from the titles. Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: Iwona Winiarska <iwona.winiarska@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230122184834.181977-1-sj@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-05sched/documentation: Document the util clamp featureQais Yousef
Add a document explaining the util clamp feature: what it is and how to use it. The new document hopefully covers everything one needs to know about uclamp. Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Qais Yousef (Google) <qyousef@layalina.io> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lore.kernel.org/r/20221216235716.201923-1-qyousef@layalina.io Cc: Jonathan Corbet <corbet@lwn.net>
2022-09-27docs: scheduler: Update new path for the sysctl knobsLukasz Luba
Add missing update for the documentation bit of some scheduler knob. The knobs have been moved to /debug/sched/ location (with adjusted names). Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Alex Shi <alexs@kernel.org> Tested-by: Yanteng Si <siyanteng@loongson.cn> Link: https://lore.kernel.org/r/20220816121907.841-1-lukasz.luba@arm.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-16docs/scheduler: fix unit errorJui-Tse Huang
The unit mentioned in the documentation of scheduler statistics is outdated which may mislead the readers. The unit of statistics that is reported by /proc/schedstat is modified to nanosecond, and the unit of statistics that is reported by /proc/PID/schedstat is provided as well to make the context consistent. The rq_cpu_time and the rq_sched_info.run_delay of a run queue, and the sched_info.run_delay of a task are all updated based on the clock of the run queue, while the se.sum_exec_runtime of a task is updated based on the clock_task of the run queue of the task. Both the clock and clock_task are relied on the return value of the function sched_clock() which is in the unit of nanosecond. Signed-off-by: Jui-Tse Huang <juitse.huang@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-16docs/scheduler: Change unit of cpu_time and rq_time to nanosecondsChunguang Xu
In the current implementation, cpu_time and rq_time should be in nanoseconds, so this document needs to be modified. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-22Merge tag 'sched-core-2022-03-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Cleanups for SCHED_DEADLINE - Tracing updates/fixes - CPU Accounting fixes - First wave of changes to optimize the overhead of the scheduler build, from the fast-headers tree - including placeholder *_api.h headers for later header split-ups. - Preempt-dynamic using static_branch() for ARM64 - Isolation housekeeping mask rework; preperatory for further changes - NUMA-balancing: deal with CPU-less nodes - NUMA-balancing: tune systems that have multiple LLC cache domains per node (eg. AMD) - Updates to RSEQ UAPI in preparation for glibc usage - Lots of RSEQ/selftests, for same - Add Suren as PSI co-maintainer * tag 'sched-core-2022-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (81 commits) sched/headers: ARM needs asm/paravirt_api_clock.h too sched/numa: Fix boot crash on arm64 systems headers/prep: Fix header to build standalone: <linux/psi.h> sched/headers: Only include <linux/entry-common.h> when CONFIG_GENERIC_ENTRY=y cgroup: Fix suspicious rcu_dereference_check() usage warning sched/preempt: Tell about PREEMPT_DYNAMIC on kernel headers sched/topology: Remove redundant variable and fix incorrect type in build_sched_domains sched/deadline,rt: Remove unused parameter from pick_next_[rt|dl]_entity() sched/deadline,rt: Remove unused functions for !CONFIG_SMP sched/deadline: Use __node_2_[pdl|dle]() and rb_first_cached() consistently sched/deadline: Merge dl_task_can_attach() and dl_cpu_busy() sched/deadline: Move bandwidth mgmt and reclaim functions into sched class source file sched/deadline: Remove unused def_dl_bandwidth sched/tracing: Report TASK_RTLOCK_WAIT tasks as TASK_UNINTERRUPTIBLE sched/tracing: Don't re-read p->state when emitting sched_switch event sched/rt: Plug rt_mutex_setprio() vs push_rt_task() race sched/cpuacct: Remove redundant RCU read lock sched/cpuacct: Optimize away RCU read lock sched/cpuacct: Fix charge percpu cpuusage sched/headers: Reorganize, clean up and optimize kernel/sched/sched.h dependencies ...
2022-03-16docs: scheduler: Convert schedutil.txt to ReSTTang Yizhou
All other scheduler documents have been converted to *.rst. Let's do the same for schedutil.txt. Also fixed some typos. Signed-off-by: Tang Yizhou <tangyizhou@huawei.com> Link: https://lore.kernel.org/r/20220312070751.16844-1-tangyizhou@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-11sched/numa-balancing: Move some document to make it consistent with the codeHuang Ying
After commit 8a99b6833c88 ("sched: Move SCHED_DEBUG sysctl to debugfs"), some NUMA balancing sysctls enclosed with SCHED_DEBUG has been moved to debugfs. This patch move the document for these sysctls from Documentation/admin-guide/sysctl/kernel.rst to Documentation/scheduler/sched-debug.rst to make the document consistent with the code. Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Link: https://lkml.kernel.org/r/20220210052514.3038279-1-ying.huang@intel.com
2022-02-01docs: scheduler: Fix outdated parameter of rebalance_domainsTang Yizhou
According to the function prototype of rebalance_domains(), its first parameter is *rq* and the document need to be updated. Signed-off-by: Tang Yizhou <tangyizhou@huawei.com> Link: https://lore.kernel.org/r/20211221031818.23186-1-tangyizhou@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-12-06docs/scheduler: fix typo and warning in sched-bwcYanteng Si
a) since d73df887b6b8 ("sched/fair: Add document for burstable CFS bandwidth") [cpu.cfs_quota_us: the total available run-time within a period (in] shoud be removed, let's delete it. b) Add a period. c) fix a build warning: linux-next/Documentation/scheduler/sched-bwc.rst:243: WARNING: Inline emphasis start-string without end-string. Signed-off-by: Yanteng Si <siyanteng@loongson.cn> Reviewed-by: Alex Shi <alexs@kernel.org> Link: https://lore.kernel.org/r/163a4dde20b8c4b68d668977a668e281d18fcf92.1638517064.git.siyanteng@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-10-05sched/fair: Add document for burstable CFS bandwidthHuaixin Chang
Basic description of usage and effect for CFS Bandwidth Control Burst. Co-developed-by: Shanpei Chen <shanpeic@linux.alibaba.com> Signed-off-by: Shanpei Chen <shanpeic@linux.alibaba.com> Co-developed-by: Tianchen Ding <dtcccc@linux.alibaba.com> Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com> Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210830032215.16302-3-changhuaixin@linux.alibaba.com
2021-06-28Merge tag 'docs-5.14' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This was a reasonably active cycle for documentation; this includes: - Some kernel-doc cleanups. That script is still regex onslaught from hell, but it has gotten a little better. - Improvements to the checkpatch docs, which are also used by the tool itself. - A major update to the pathname lookup documentation. - Elimination of :doc: markup, since our automarkup magic can create references from filenames without all the extra noise. - The flurry of Chinese translation activity continues. Plus, of course, the usual collection of updates, typo fixes, and warning fixes" * tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits) docs: path-lookup: use bare function() rather than literals docs: path-lookup: update symlink description docs: path-lookup: update get_link() ->follow_link description docs: path-lookup: update WALK_GET, WALK_PUT desc docs: path-lookup: no get_link() docs: path-lookup: update i_op->put_link and cookie description docs: path-lookup: i_op->follow_link replaced with i_op->get_link docs: path-lookup: Add macro name to symlink limit description docs: path-lookup: remove filename_mountpoint docs: path-lookup: update do_last() part docs: path-lookup: update path_mountpoint() part docs: path-lookup: update path_to_nameidata() part docs: path-lookup: update follow_managed() part docs: Makefile: Use CONFIG_SHELL not SHELL docs: Take a little noise out of the build process docs: x86: avoid using ReST :doc:`foo` markup docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup ...
2021-06-24sched/doc: Update the CPU capacity asymmetry bitsBeata Michalska
Update the documentation bits referring to capacity aware scheduling with regards to newly introduced SD_ASYM_CPUCAPACITY_FULL sched_domain flag. Signed-off-by: Beata Michalska <beata.michalska@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Link: https://lore.kernel.org/r/20210603140627.8409-4-beata.michalska@arm.com
2021-05-20docs: sched-bwc.rst: fix a typo on a doc nameMauro Carvalho Chehab
cgroupv2.rst -> cgroup-v2.rst Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/1dc0203bd7df375ef45832f0c88566e22c4138ff.1621413933.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-17Documentation: scheduler: fixed 2 typos in sched-nice-design.rstChun-Hung Tseng
This patch fixed 2 spelling errors in the documentation. Signed-off-by: Chun-Hung Tseng <henrybear327@gmail.com> Link: https://lore.kernel.org/r/20210516105955.120651-1-henrybear327@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-06sched,doc: sched_debug_verbose cmdline should be sched_verboseBarry Song
The cmdline should include sched_verbose but not sched_debug_verbose as sched_debug_verbose is only the variant name in code. Fixes: 9406415f46 ("sched/debug: Rename the sched_debug parameter to sched_verbose") Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210504105344.31344-1-song.bao.hua@hisilicon.com
2021-04-17sched/debug: Rename the sched_debug parameter to sched_verbosePeter Zijlstra
CONFIG_SCHED_DEBUG is the build-time Kconfig knob, the boot param sched_debug and the /debug/sched/debug_enabled knobs control the sched_debug_enabled variable, but what they really do is make SCHED_DEBUG more verbose, so rename the lot. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-02-22Merge tag 'docs-5.12' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively quiet cycle in docsland. - As promised, the minimum Sphinx version to build the docs is now 1.7, and we have dropped support for Python 2 entirely. That allowed the removal of a bunch of compatibility code. - A set of treewide warning fixups from Mauro that I applied after it became clear nobody else was going to deal with them. - The automarkup mechanism can now create cross-references from relative paths to RST files. - More translations, typo fixes, and warning fixes" * tag 'docs-5.12' of git://git.lwn.net/linux: (75 commits) docs: kernel-hacking: be more civil docs: Remove the Microsoft rhetoric Documentation/admin-guide: kernel-parameters: Update nohlt section doc/admin-guide: fix spelling mistake: "perfomance" -> "performance" docs: Document cross-referencing using relative path docs: Enable usage of relative paths to docs on automarkup docs: thermal: fix spelling mistakes Documentation: admin-guide: Update kvm/xen config option docs: Make syscalls' helpers naming consistent coding-style.rst: Avoid comma statements Documentation: /proc/loadavg: add 3 more field descriptions Documentation/submitting-patches: Add blurb about backtraces in commit messages Docs: drop Python 2 support Move our minimum Sphinx version to 1.7 Documentation: input: define ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams scripts/kernel-doc: add internal hyperlink to DOC: sections Update Documentation/admin-guide/sysctl/fs.rst docs: Update DTB format references docs: zh_CN: add iio index.rst translation docs/zh_CN: add iio ep93xx_adc.rst translation ...
2021-01-21docs/scheduler/sched-bwc: note/link cgroup v2Kir Kolyshkin
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210120001824.385168-6-kolyshkin@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-21docs/scheduler/sched-bwc: fix note renderingKir Kolyshkin
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210120001824.385168-4-kolyshkin@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-21docs/scheduler/sched-design-CFS: formatting fixKir Kolyshkin
Fix the rendering of the paragraph. Before the fix, the first line is rendered in bold (I'm not quite sure why) and is also separated from the rest of the paragraph, which is rendered with an indent. Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20210120001824.385168-3-kolyshkin@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>