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2020-01-28Merge branch 'linus' of ↵Linus Torvalds1-192/+194
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Removed CRYPTO_TFM_RES flags - Extended spawn grabbing to all algorithm types - Moved hash descsize verification into API code Algorithms: - Fixed recursive pcrypt dead-lock - Added new 32 and 64-bit generic versions of poly1305 - Added cryptogams implementation of x86/poly1305 Drivers: - Added support for i.MX8M Mini in caam - Added support for i.MX8M Nano in caam - Added support for i.MX8M Plus in caam - Added support for A33 variant of SS in sun4i-ss - Added TEE support for Raven Ridge in ccp - Added in-kernel API to submit TEE commands in ccp - Added AMD-TEE driver - Added support for BCM2711 in iproc-rng200 - Added support for AES256-GCM based ciphers for chtls - Added aead support on SEC2 in hisilicon" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (244 commits) crypto: arm/chacha - fix build failured when kernel mode NEON is disabled crypto: caam - add support for i.MX8M Plus crypto: x86/poly1305 - emit does base conversion itself crypto: hisilicon - fix spelling mistake "disgest" -> "digest" crypto: chacha20poly1305 - add back missing test vectors and test chunking crypto: x86/poly1305 - fix .gitignore typo tee: fix memory allocation failure checks on drv_data and amdtee crypto: ccree - erase unneeded inline funcs crypto: ccree - make cc_pm_put_suspend() void crypto: ccree - split overloaded usage of irq field crypto: ccree - fix PM race condition crypto: ccree - fix FDE descriptor sequence crypto: ccree - cc_do_send_request() is void func crypto: ccree - fix pm wrongful error reporting crypto: ccree - turn errors to debug msgs crypto: ccree - fix AEAD decrypt auth fail crypto: ccree - fix typo in comment crypto: ccree - fix typos in error msgs crypto: atmel-{aes,sha,tdes} - Retire crypto_platform_data crypto: x86/sha - Eliminate casts on asm implementations ...
2020-01-28Merge branch 'sched-core-for-linus' of ↵Linus Torvalds19-191/+315
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "These were the main changes in this cycle: - More -rt motivated separation of CONFIG_PREEMPT and CONFIG_PREEMPTION. - Add more low level scheduling topology sanity checks and warnings to filter out nonsensical topologies that break scheduling. - Extend uclamp constraints to influence wakeup CPU placement - Make the RT scheduler more aware of asymmetric topologies and CPU capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y - Make idle CPU selection more consistent - Various fixes, smaller cleanups, updates and enhancements - please see the git log for details" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) sched/fair: Define sched_idle_cpu() only for SMP configurations sched/topology: Assert non-NUMA topology masks don't (partially) overlap idle: fix spelling mistake "iterrupts" -> "interrupts" sched/fair: Remove redundant call to cpufreq_update_util() sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP sched/fair: calculate delta runnable load only when it's needed sched/cputime: move rq parameter in irqtime_account_process_tick stop_machine: Make stop_cpus() static sched/debug: Reset watchdog on all CPUs while processing sysrq-t sched/core: Fix size of rq::uclamp initialization sched/uclamp: Fix a bug in propagating uclamp value in new cgroups sched/fair: Load balance aggressively for SCHED_IDLE CPUs sched/fair : Improve update_sd_pick_busiest for spare capacity case watchdog: Remove soft_lockup_hrtimer_cnt and related code sched/rt: Make RT capacity-aware sched/fair: Make EAS wakeup placement consider uclamp restrictions sched/fair: Make task_fits_capacity() consider uclamp restrictions sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with() sched/uclamp: Make uclamp util helpers use and return UL values ...
2020-01-28Merge branch 'perf-core-for-linus' of ↵Linus Torvalds10-236/+185
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Kernel side changes: - Ftrace is one of the last W^X violators (after this only KLP is left). These patches move it over to the generic text_poke() interface and thereby get rid of this oddity. This requires a surprising amount of surgery, by Peter Zijlstra. - x86/AMD PMUs: add support for 'Large Increment per Cycle Events' to count certain types of events that have a special, quirky hw ABI (by Kim Phillips) - kprobes fixes by Masami Hiramatsu Lots of tooling updates as well, the following subcommands were updated: annotate/report/top, c2c, clang, record, report/top TUI, sched timehist, tests; plus updates were done to the gtk ui, libperf, headers and the parser" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) perf/x86/amd: Add support for Large Increment per Cycle Events perf/x86/amd: Constrain Large Increment per Cycle events perf/x86/intel/rapl: Add Comet Lake support tracing: Initialize ret in syscall_enter_define_fields() perf header: Use last modification time for timestamp perf c2c: Fix return type for histogram sorting comparision functions perf beauty sockaddr: Fix augmented syscall format warning perf/ui/gtk: Fix gtk2 build perf ui gtk: Add missing zalloc object perf tools: Use %define api.pure full instead of %pure-parser libperf: Setup initial evlist::all_cpus value perf report: Fix no libunwind compiled warning break s390 issue perf tools: Support --prefix/--prefix-strip perf report: Clarify in help that --children is default tools build: Fix test-clang.cpp with Clang 8+ perf clang: Fix build with Clang 9 kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic tools lib: Fix builds when glibc contains strlcpy() perf report/top: Make 'e' visible in the help and make it toggle showing callchains perf report/top: Do not offer annotation for symbols without samples ...
2020-01-28Merge branch 'locking-core-for-linus' of ↵Linus Torvalds3-21/+19
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "Just a handful of changes in this cycle: an ARM64 performance optimization, a comment fix and a debug output fix" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/osq: Use optimized spinning loop for arm64 locking/qspinlock: Fix inaccessible URL of MCS lock paper locking/lockdep: Fix lockdep_stats indentation problem
2020-01-28Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds17-385/+778
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The RCU changes in this cycle were: - Expedited grace-period updates - kfree_rcu() updates - RCU list updates - Preemptible RCU updates - Torture-test updates - Miscellaneous fixes - Documentation updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits) rcu: Remove unused stop-machine #include powerpc: Remove comment about read_barrier_depends() .mailmap: Add entries for old paulmck@kernel.org addresses srcu: Apply *_ONCE() to ->srcu_last_gp_end rcu: Switch force_qs_rnp() to for_each_leaf_node_cpu_mask() rcu: Move rcu_{expedited,normal} definitions into rcupdate.h rcu: Move gp_state_names[] and gp_state_getname() to tree_stall.h rcu: Remove the declaration of call_rcu() in tree.h rcu: Fix tracepoint tracking RCU CPU kthread utilization rcu: Fix harmless omission of "CONFIG_" from #if condition rcu: Avoid tick_dep_set_cpu() misordering rcu: Provide wrappers for uses of ->rcu_read_lock_nesting rcu: Use READ_ONCE() for ->expmask in rcu_read_unlock_special() rcu: Clear ->rcu_read_unlock_special only once rcu: Clear .exp_hint only when deferred quiescent state has been reported rcu: Rename some instance of CONFIG_PREEMPTION to CONFIG_PREEMPT_RCU rcu: Remove kfree_call_rcu_nobatch() rcu: Remove kfree_rcu() special casing and lazy-callback handling rcu: Add support for debug_objects debugging for kfree_rcu() rcu: Add multiple in-flight batches of kfree_rcu() work ...
2020-01-28Merge branch 'core/kprobes' into perf/core, to pick up fixesIngo Molnar2-25/+45
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-27Merge tag 'irq-core-2020-01-28' of ↵Linus Torvalds6-5/+87
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "The interrupt departement provides: - A mechanism to shield isolated tasks from managed interrupts: The affinity of managed interrupts is completely controlled by the kernel and user space has no influence on them. The reason is that the automatically assigned affinity correlates to the multi-queue CPU handling of block devices. If the generated affinity mask spaws both housekeeping and isolated CPUs the interrupt could be routed to an isolated CPU which would then be disturbed by I/O submitted by a housekeeping CPU. The new mechamism ensures that as long as one housekeeping CPU is online in the assigned affinity mask the interrupt is routed to a housekeeping CPU. If there is no online housekeeping CPU in the affinity mask, then the interrupt is routed to an isolated CPU to keep the device queue intact, but unless the isolated CPU submits I/O by itself these interrupts are not raised. - A small addon to the device tree irqdomain core code to avoid duplication in irq chip drivers - Conversion of the SiFive PLIC to hierarchical domains - The usual pile of new irq chip drivers: SiFive GPIO, Aspeed SCI, NXP INTMUX, Meson A1 GPIO - The first cut of support for the new ARM GICv4.1 - The usual pile of fixes and improvements in core and driver code" * tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits) genirq, sched/isolation: Isolate from handling managed interrupts irqchip/gic-v4.1: Allow direct invalidation of VLPIs irqchip/gic-v4.1: Suppress per-VLPI doorbell irqchip/gic-v4.1: Add VPE INVALL callback irqchip/gic-v4.1: Add VPE eviction callback irqchip/gic-v4.1: Add VPE residency callback irqchip/gic-v4.1: Add mask/unmask doorbell callbacks irqchip/gic-v4.1: Plumb skeletal VPE irqchip irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP irqchip/gic-v4.1: Don't use the VPE proxy if RVPEID is set irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocation irqchip/gic-v3: Add GICv4.1 VPEID size discovery irqchip/gic-v3: Detect GICv4.1 supporting RVPEID irqchip/gic-v3-its: Fix get_vlpi_map() breakage with doorbells irqdomain: Fix a memory leak in irq_domain_push_irq() irqchip: Add NXP INTMUX interrupt multiplexer support dt-bindings: interrupt-controller: Add binding for NXP INTMUX interrupt multiplexer irqchip: Define EXYNOS_IRQ_COMBINER irqchip/meson-gpio: Add support for meson a1 SoCs ...
2020-01-27Merge tag 'smp-core-2020-01-28' of ↵Linus Torvalds2-63/+48
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core SMP updates from Thomas Gleixner: "A small set of SMP core code changes: - Rework the smp function call core code to avoid the allocation of an additional cpumask - Remove the not longer required GFP argument from on_each_cpu_cond() and on_each_cpu_cond_mask() and fixup the callers" * tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smp: Remove allocation mask from on_each_cpu_cond.*() smp: Add a smp_cond_func_t argument to smp_call_function_many() smp: Use smp_cond_func_t as type for the conditional function
2020-01-27Merge tag 'timers-core-2020-01-27' of ↵Linus Torvalds13-117/+703
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The timekeeping and timers departement provides: - Time namespace support: If a container migrates from one host to another then it expects that clocks based on MONOTONIC and BOOTTIME are not subject to disruption. Due to different boot time and non-suspended runtime these clocks can differ significantly on two hosts, in the worst case time goes backwards which is a violation of the POSIX requirements. The time namespace addresses this problem. It allows to set offsets for clock MONOTONIC and BOOTTIME once after creation and before tasks are associated with the namespace. These offsets are taken into account by timers and timekeeping including the VDSO. Offsets for wall clock based clocks (REALTIME/TAI) are not provided by this mechanism. While in theory possible, the overhead and code complexity would be immense and not justified by the esoteric potential use cases which were discussed at Plumbers '18. The overhead for tasks in the root namespace (ie where host time offsets = 0) is in the noise and great effort was made to ensure that especially in the VDSO. If time namespace is disabled in the kernel configuration the code is compiled out. Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature and kept on for more than a year addressing review comments, finding better solutions. A pleasant experience. - Overhaul of the alarmtimer device dependency handling to ensure that the init/suspend/resume ordering is correct. - A new clocksource/event driver for Microchip PIT64 - Suspend/resume support for the Hyper-V clocksource - The usual pile of fixes, updates and improvements mostly in the driver code" * tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n alarmtimer: Use wakeup source from alarmtimer platform device alarmtimer: Make alarmtimer platform device child of RTC device alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality hrtimer: Add missing sparse annotation for __run_timer() lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres() MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources clocksource/drivers/timer-microchip-pit64b: Fix sparse warning clocksource/drivers/exynos_mct: Rename Exynos to lowercase clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access clocksource/drivers/timer-ti-dm: Switch to platform_get_irq clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource clocksource/drivers/bcm2835_timer: Fix memory leak of timer clocksource/drivers/cadence-ttc: Use ttc driver as platform driver clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page ...
2020-01-27Merge tag 'core-core-2020-01-28' of ↵Linus Torvalds1-24/+7
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull watchdog updates from Thomas Gleixner: "A set of watchdog/softlockup related improvements: - Enforce that the watchdog timestamp is always valid on boot. The original implementation caused a watchdog disabled gap of one second in the boot process due to truncation of the underlying sched clock. The sched clock is divided by 1e9 to convert nanoseconds to seconds. So for the first second of the boot process the result is 0 which is at the same time the indicator to disable the watchdog. The trivial fix is to change the disabled indicator to ULONG_MAX. - Two cleanup patches removing unused and redundant code which got forgotten to be cleaned up in previous changes" * tag 'core-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: watchdog/softlockup: Enforce that timestamp is valid on boot watchdog/softlockup: Remove obsolete check of last reported task watchdog: Remove soft_lockup_hrtimer_cnt and related code
2020-01-27Merge tag 'timers-urgent-2020-01-27' of ↵Linus Torvalds1-20/+17
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two fixes for the generic VDSO code which missed 5.5: - Make the update to the coarse timekeeper unconditional. This is required because the coarse timekeeper interfaces in the VDSO do not depend on a VDSO capable clocksource. If the system does not have a VDSO capable clocksource and the update is depending on the VDSO capable clocksource, the coarse VDSO interfaces would operate on stale data forever. - Invert the logic of __arch_update_vdso_data() to avoid further head scratching. Tripped over this several times while analyzing the update problem above" * tag 'timers-urgent-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lib/vdso: Update coarse timekeeper unconditionally lib/vdso: Make __arch_update_vdso_data() logic understandable
2020-01-27Merge tag 'audit-pr-20200127' of ↵Linus Torvalds1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit update from Paul Moore: "One small audit patch for the Linux v5.6 merge window, and unsurprisingly it passes our test suite with flying colors" * tag 'audit-pr-20200127' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: Add __rcu annotation to RCU pointer
2020-01-27Merge branch 'for-5.6' of ↵Linus Torvalds2-6/+7
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - cgroup2 interface for hugetlb controller. I think this was the last remaining bit which was missing from cgroup2 - fixes for race and a spurious warning in threaded cgroup handling - other minor changes * 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: iocost: Fix iocost_monitor.py due to helper type mismatch cgroup: Prevent double killing of css when enabling threaded cgroup cgroup: fix function name in comment mm: hugetlb controller for cgroups v2
2020-01-27Merge branch 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-1/+1
Pull workqueue updates from Tejun Heo: "Just a couple tracepoint patches" * 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: remove workqueue_work event class workqueue: add worker function to workqueue_execute_end tracepoint
2020-01-27Merge tag 'pm-5.6-rc1' of ↵Linus Torvalds6-28/+69
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add ACPI support to the intel_idle driver along with an admin guide document for it, add support for CPR (Core Power Reduction) to the AVS (Adaptive Voltage Scaling) subsystem, add new hardware support in a few places, add some new sysfs attributes, debugfs files and tracepoints, fix bugs and clean up a bunch of things all over. Specifics: - Update the ACPI processor driver in order to export acpi_processor_evaluate_cst() to the code outside of it, add ACPI support to the intel_idle driver based on that and clean up that driver somewhat (Rafael Wysocki). - Add an admin guide document for the intel_idle driver (Rafael Wysocki). - Clean up cpuidle core and drivers, enable compilation testing for some of them (Benjamin Gaignard, Krzysztof Kozlowski, Rafael Wysocki, Yangtao Li). - Fix reference counting of OPP (operating performance points) table structures (Viresh Kumar). - Add support for CPR (Core Power Reduction) to the AVS (Adaptive Voltage Scaling) subsystem (Niklas Cassel, Colin Ian King, YueHaibing). - Add support for TigerLake Mobile and JasperLake to the Intel RAPL power capping driver (Zhang Rui). - Update cpufreq drivers: - Add i.MX8MP support to imx-cpufreq-dt (Anson Huang). - Fix usage of a macro in loongson2_cpufreq (Alexandre Oliva). - Fix cpufreq policy reference counting issues in s3c and brcmstb-avs (chenqiwu). - Fix ACPI table reference counting issue and HiSilicon quirk handling in the CPPC driver (Hanjun Guo). - Clean up spelling mistake in intel_pstate (Harry Pan). - Convert the kirkwood and tegra186 drivers to using devm_platform_ioremap_resource() (Yangtao Li). - Update devfreq core: - Add 'name' sysfs attribute for devfreq devices (Chanwoo Choi). - Clean up the handing of transition statistics and allow them to be reset by writing 0 to the 'trans_stat' devfreq device attribute in sysfs (Kamil Konieczny). - Add 'devfreq_summary' to debugfs (Chanwoo Choi). - Clean up kerneldoc comments and Kconfig indentation (Krzysztof Kozlowski, Randy Dunlap). - Update devfreq drivers: - Add dynamic scaling for the imx8m DDR controller and clean up imx8m-ddrc (Leonard Crestez, YueHaibing). - Fix DT node reference counting and nitialization error code path in rk3399_dmc and add COMPILE_TEST and HAVE_ARM_SMCCC dependency for it (Chanwoo Choi, Yangtao Li). - Fix DT node reference counting in rockchip-dfi and make it use devm_platform_ioremap_resource() (Yangtao Li). - Fix excessive stack usage in exynos-ppmu (Arnd Bergmann). - Fix initialization error code paths in exynos-bus (Yangtao Li). - Clean up exynos-bus and exynos somewhat (Artur Świgoń, Krzysztof Kozlowski). - Add tracepoints for tracking usage_count updates unrelated to status changes in PM-runtime (Michał Mirosław). - Add sysfs attribute to control the "sync on suspend" behavior during system-wide suspend (Jonas Meurer). - Switch system-wide suspend tests over to 64-bit time (Alexandre Belloni). - Make wakeup sources statistics in debugfs cover deleted ones which used to be the case some time ago (zhuguangqing). - Clean up computations carried out during hibernation, update messages related to hibernation and fix a spelling mistake in one of them (Wen Yang, Luigi Semenzato, Colin Ian King). - Add mailmap entry for maintainer e-mail address that has not been functional for several years (Rafael Wysocki)" * tag 'pm-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (83 commits) cpufreq: loongson2_cpufreq: adjust cpufreq uses of LOONGSON_CHIPCFG intel_idle: Clean up irtl_2_usec() intel_idle: Move 3 functions closer to their callers intel_idle: Annotate initialization code and data structures intel_idle: Move and clean up intel_idle_cpuidle_devices_uninit() intel_idle: Rearrange intel_idle_cpuidle_driver_init() intel_idle: Clean up NULL pointer check in intel_idle_init() intel_idle: Fold intel_idle_probe() into intel_idle_init() intel_idle: Eliminate __setup_broadcast_timer() cpuidle: fix cpuidle_find_deepest_state() kerneldoc warnings cpuidle: sysfs: fix warnings when compiling with W=1 cpuidle: coupled: fix warnings when compiling with W=1 cpufreq: brcmstb-avs: fix imbalance of cpufreq policy refcount PM: suspend: Add sysfs attribute to control the "sync on suspend" behavior PM / devfreq: Add debugfs support with devfreq_summary file Documentation: admin-guide: PM: Add intel_idle document cpuidle: arm: Enable compile testing for some of drivers PM-runtime: add tracepoints for usage_count changes cpufreq: intel_pstate: fix spelling mistake: "Whethet" -> "Whether" PM: hibernate: fix spelling mistake "shapshot" -> "snapshot" ...
2020-01-27Merge tag 'arm64-upstream' of ↵Linus Torvalds4-1/+17
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The changes are a real mixed bag this time around. The only scary looking one from the diffstat is the uapi change to asm-generic/mman-common.h, but this has been acked by Arnd and is actually just adding a pair of comments in an attempt to prevent allocation of some PROT values which tend to get used for arch-specific purposes. We'll be using them for Branch Target Identification (a CFI-like hardening feature), which is currently under review on the mailing list. New architecture features: - Support for Armv8.5 E0PD, which benefits KASLR in the same way as KPTI but without the overhead. This allows KPTI to be disabled on CPUs that are not affected by Meltdown, even is KASLR is enabled. - Initial support for the Armv8.5 RNG instructions, which claim to provide access to a high bandwidth, cryptographically secure hardware random number generator. As well as exposing these to userspace, we also use them as part of the KASLR seed and to seed the crng once all CPUs have come online. - Advertise a bunch of new instructions to userspace, including support for Data Gathering Hint, Matrix Multiply and 16-bit floating point. Kexec: - Cleanups in preparation for relocating with the MMU enabled - Support for loading crash dump kernels with kexec_file_load() Perf and PMU drivers: - Cleanups and non-critical fixes for a couple of system PMU drivers FPU-less (aka broken) CPU support: - Considerable fixes to support CPUs without the FP/SIMD extensions, including their presence in heterogeneous systems. Good luck finding a 64-bit userspace that handles this. Modern assembly function annotations: - Start migrating our use of ENTRY() and ENDPROC() over to the new-fangled SYM_{CODE,FUNC}_{START,END} macros, which are intended to aid debuggers Kbuild: - Cleanup detection of LSE support in the assembler by introducing 'as-instr' - Remove compressed Image files when building clean targets IP checksumming: - Implement optimised IPv4 checksumming routine when hardware offload is not in use. An IPv6 version is in the works, pending testing. Hardware errata: - Work around Cortex-A55 erratum #1530923 Shadow call stack: - Work around some issues with Clang's integrated assembler not liking our perfectly reasonable assembly code - Avoid allocating the X18 register, so that it can be used to hold the shadow call stack pointer in future ACPI: - Fix ID count checking in IORT code. This may regress broken firmware that happened to work with the old implementation, in which case we'll have to revert it and try something else - Fix DAIF corruption on return from GHES handler with pseudo-NMIs Miscellaneous: - Whitelist some CPUs that are unaffected by Spectre-v2 - Reduce frequency of ASID rollover when KPTI is compiled in but inactive - Reserve a couple of arch-specific PROT flags that are already used by Sparc and PowerPC and are planned for later use with BTI on arm64 - Preparatory cleanup of our entry assembly code in preparation for moving more of it into C later on - Refactoring and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (73 commits) arm64: acpi: fix DAIF manipulation with pNMI arm64: kconfig: Fix alignment of E0PD help text arm64: Use v8.5-RNG entropy for KASLR seed arm64: Implement archrandom.h for ARMv8.5-RNG arm64: kbuild: remove compressed images on 'make ARCH=arm64 (dist)clean' arm64: entry: Avoid empty alternatives entries arm64: Kconfig: select HAVE_FUTEX_CMPXCHG arm64: csum: Fix pathological zero-length calls arm64: entry: cleanup sp_el0 manipulation arm64: entry: cleanup el0 svc handler naming arm64: entry: mark all entry code as notrace arm64: assembler: remove smp_dmb macro arm64: assembler: remove inherit_daif macro ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map() mm: Reserve asm-generic prot flags 0x10 and 0x20 for arch use arm64: Use macros instead of hard-coded constants for MAIR_EL1 arm64: Add KRYO{3,4}XX CPU cores to spectre-v2 safe list arm64: kernel: avoid x18 in __cpu_soft_restart arm64: kvm: stop treating register x18 as caller save arm64/lib: copy_page: avoid x18 register in assembler code ...
2020-01-27Merge branches 'pm-cpufreq' and 'pm-sleep'Rafael J. Wysocki6-28/+69
* pm-cpufreq: cpufreq: loongson2_cpufreq: adjust cpufreq uses of LOONGSON_CHIPCFG cpufreq: brcmstb-avs: fix imbalance of cpufreq policy refcount cpufreq: intel_pstate: fix spelling mistake: "Whethet" -> "Whether" cpufreq: s3c: fix unbalances of cpufreq policy refcount cpufreq: imx-cpufreq-dt: Add i.MX8MP support cpufreq: Use imx-cpufreq-dt for i.MX8MP's speed grading cpufreq: tegra186: convert to devm_platform_ioremap_resource cpufreq: kirkwood: convert to devm_platform_ioremap_resource cpufreq: CPPC: put ACPI table after using it cpufreq : CPPC: Break out if HiSilicon CPPC workaround is matched * pm-sleep: PM: suspend: Add sysfs attribute to control the "sync on suspend" behavior PM: hibernate: fix spelling mistake "shapshot" -> "snapshot" PM: hibernate: Add more logging on hibernation failure PM: hibernate: improve arithmetic division in preallocate_highmem_fraction() PM: wakeup: Show statistics for deleted wakeup sources again PM: sleep: Switch to rtc_time64_to_tm()/rtc_tm_to_time64()
2020-01-25Merge branch 'for-mingo' of ↵Ingo Molnar17-385/+778
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - Expedited grace-period updates - kfree_rcu() updates - RCU list updates - Preemptible RCU updates - Torture-test updates - Miscellaneous fixes - Documentation updates Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-24alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=nStephen Boyd1-5/+0
The stubbed version of alarmtimer_get_rtcdev() is not exported. so this won't work if this function is used in a module when CONFIG_RTC_CLASS=n. Move the stub function to the header file and make it inline so that callers don't have to worry about linking against this symbol. rtcdev isn't used outside of this ifdef so it's not required to be redefined to NULL. Drop that while touching this area. Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20200124055849.154411-4-swboyd@chromium.org
2020-01-24alarmtimer: Use wakeup source from alarmtimer platform deviceStephen Boyd1-10/+5
Use the wakeup source that can be associated with the 'alarmtimer' platform device instead of registering another one by hand. Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200124055849.154411-3-swboyd@chromium.org
2020-01-24alarmtimer: Make alarmtimer platform device child of RTC deviceStephen Boyd1-11/+9
The alarmtimer_suspend() function will fail if an RTC device is on a bus such as SPI or i2c and that RTC device registers and probes after alarmtimer_init() registers and probes the 'alarmtimer' platform device. This is because system wide suspend suspends devices in the reverse order of their probe. When alarmtimer_suspend() attempts to program the RTC for a wakeup it will try to program an RTC device on a bus that has already been suspended. Move the alarmtimer device registration to happen when the RTC which is used for wakeup is registered. Register the 'alarmtimer' platform device as a child of the RTC device too, so that it can be guaranteed that the RTC device won't be suspended when alarmtimer_suspend() is called. Reported-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200124055849.154411-2-swboyd@chromium.org
2020-01-24alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect realityStephen Boyd1-2/+0
This function doesn't do anything like this comment says when an RTC device hasn't been chosen. It looks like we used to do something like that before commit 8bc0dafb5cf3 ("alarmtimers: Rework RTC device selection using class interface") but that's long gone now. Remove this sentence to avoid confusing the reader. Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20200124055849.154411-5-swboyd@chromium.org
2020-01-24smp: Remove allocation mask from on_each_cpu_cond.*()Sebastian Andrzej Siewior2-14/+6
The allocation mask is no longer used by on_each_cpu_cond() and on_each_cpu_cond_mask() and can be removed. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20200117090137.1205765-4-bigeasy@linutronix.de
2020-01-24smp: Add a smp_cond_func_t argument to smp_call_function_many()Sebastian Andrzej Siewior1-43/+38
on_each_cpu_cond_mask() allocates a new CPU mask. The newly allocated mask is a subset of the provided mask based on the conditional function. This memory allocation can be avoided by extending smp_call_function_many() with the conditional function and performing the remote function call based on the mask and the conditional function. Rename smp_call_function_many() to smp_call_function_many_cond() and add the smp_cond_func_t argument. If smp_cond_func_t is provided then it is used before invoking the function. Provide smp_call_function_many() with cond_func set to NULL. Let on_each_cpu_cond_mask() use smp_call_function_many_cond(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20200117090137.1205765-3-bigeasy@linutronix.de
2020-01-24smp: Use smp_cond_func_t as type for the conditional functionSebastian Andrzej Siewior2-12/+10
Use a typdef for the conditional function instead defining it each time in the function prototype. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20200117090137.1205765-2-bigeasy@linutronix.de
2020-01-24Merge tag 'irqchip-5.6' of ↵Thomas Gleixner1-0/+18
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip updates from Marc Zyngier: - Conversion of the SiFive PLIC to hierarchical domains - New SiFive GPIO irqchip driver - New Aspeed SCI irqchip driver - New NXP INTMUX irqchip driver - Additional support for the Meson A1 GPIO irqchip - First part of the GICv4.1 support - Assorted fixes
2020-01-24Merge branches 'doc.2019.12.10a', 'exp.2019.12.09a', 'fixes.2020.01.24a', ↵Paul E. McKenney17-385/+778
'kfree_rcu.2020.01.24a', 'list.2020.01.10a', 'preempt.2020.01.24a' and 'torture.2019.12.09a' into HEAD doc.2019.12.10a: Documentations updates exp.2019.12.09a: Expedited grace-period updates fixes.2020.01.24a: Miscellaneous fixes kfree_rcu.2020.01.24a: Batch kfree_rcu() work list.2020.01.10a: RCU-protected-list updates preempt.2020.01.24a: Preemptible RCU updates torture.2019.12.09a: Torture-test updates
2020-01-24rcu: Remove unused stop-machine #includePaul E. McKenney2-2/+0
Long ago, RCU used the stop-machine mechanism to implement expedited grace periods, but no longer does so. This commit therefore removes the no-longer-needed #includes of linux/stop_machine.h. Link: https://lwn.net/Articles/805317/ Reported-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24srcu: Apply *_ONCE() to ->srcu_last_gp_endPaul E. McKenney1-3/+4
The ->srcu_last_gp_end field is accessed from any CPU at any time by synchronize_srcu(), so non-initialization references need to use READ_ONCE() and WRITE_ONCE(). This commit therefore makes that change. Reported-by: syzbot+08f3e9d26e5541e1ecf2@syzkaller.appspotmail.com Acked-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Switch force_qs_rnp() to for_each_leaf_node_cpu_mask()Paul E. McKenney1-8/+5
Currently, force_qs_rnp() uses a for_each_leaf_node_possible_cpu() loop containing a check of the current CPU's bit in ->qsmask. This works, but this commit saves three lines by instead using for_each_leaf_node_cpu_mask(), which combines the functionality of for_each_leaf_node_possible_cpu() and leaf_node_cpu_bit(). This commit also replaces the use of the local variable "bit" with rdp->grpmask. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Move rcu_{expedited,normal} definitions into rcupdate.hBen Dooks1-2/+0
This commit moves the rcu_{expedited,normal} definitions from kernel/rcu/update.c to include/linux/rcupdate.h to make sure they are in sync, and also to avoid the following warning from sparse: kernel/ksysfs.c:150:5: warning: symbol 'rcu_expedited' was not declared. Should it be static? kernel/ksysfs.c:167:5: warning: symbol 'rcu_normal' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Move gp_state_names[] and gp_state_getname() to tree_stall.hLai Jiangshan3-22/+22
Only tree_stall.h needs to get name from GP state, so this commit moves the gp_state_names[] array and the gp_state_getname() from kernel/rcu/tree.h and kernel/rcu/tree.c, respectively, to kernel/rcu/tree_stall.h. While moving gp_state_names[], this commit uses the GCC syntax to ensure that the right string is associated with the right CPP macro. Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Remove the declaration of call_rcu() in tree.hLai Jiangshan1-1/+0
The call_rcu() function is an external RCU API that is declared in include/linux/rcupdate.h. There is thus no point in redeclaring it in kernel/rcu/tree.h, so this commit removes that redundant declaration. Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Fix tracepoint tracking RCU CPU kthread utilizationLai Jiangshan1-1/+1
In the call to trace_rcu_utilization() at the start of the loop in rcu_cpu_kthread(), "rcu_wait" is incorrect, plus this trace event needs to be hoisted above the loop to balance with either the "rcu_wait" or "rcu_yield", depending on how the loop exits. This commit therefore makes these changes. Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Fix harmless omission of "CONFIG_" from #if conditionLai Jiangshan1-2/+2
The C preprocessor macros SRCU and TINY_RCU should instead be CONFIG_SRCU and CONFIG_TINY_RCU, respectively in the #f in kernel/rcu/rcu.h. But there is no harm when "TINY_RCU" is wrongly used, which are always non-defined, which makes "!defined(TINY_RCU)" always true, which means the code block is always included, and the included code block doesn't cause any compilation error so far in CONFIG_TINY_RCU builds. It is also the reason this change should not be taken in -stable. This commit adds the needed "CONFIG_" prefix to both macros. Not for -stable. Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Avoid tick_dep_set_cpu() misorderingPaul E. McKenney1-3/+9
In the current code, rcu_nmi_enter_common() might decide to turn on the tick using tick_dep_set_cpu(), but be delayed just before doing so. Then the grace-period kthread might notice that the CPU in question had in fact gone through a quiescent state, thus turning off the tick using tick_dep_clear_cpu(). The later invocation of tick_dep_set_cpu() would then incorrectly leave the tick on. This commit therefore enlists the aid of the leaf rcu_node structure's ->lock to ensure that decisions to enable or disable the tick are carried out before they can be reversed. Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Provide wrappers for uses of ->rcu_read_lock_nestingLai Jiangshan2-21/+36
This commit provides wrapper functions for uses of ->rcu_read_lock_nesting to improve readability and to ease future changes to support inlining of __rcu_read_lock() and __rcu_read_unlock(). Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Use READ_ONCE() for ->expmask in rcu_read_unlock_special()Paul E. McKenney1-1/+1
The rcu_node structure's ->expmask field is updated only when holding the ->lock, but is also accessed locklessly. This means that all ->expmask updates must use WRITE_ONCE() and all reads carried out without holding ->lock must use READ_ONCE(). This commit therefore changes the lockless ->expmask read in rcu_read_unlock_special() to use READ_ONCE(). Reported-by: syzbot+99f4ddade3c22ab0cf23@syzkaller.appspotmail.com Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Marco Elver <elver@google.com>
2020-01-24rcu: Clear ->rcu_read_unlock_special only onceLai Jiangshan1-16/+3
In rcu_preempt_deferred_qs_irqrestore(), ->rcu_read_unlock_special is cleared one piece at a time. Given that the "if" statements in this function use the copy in "special", this commit removes the clearing of the individual pieces in favor of clearing ->rcu_read_unlock_special in one go just after it has been determined to be non-zero. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Clear .exp_hint only when deferred quiescent state has been reportedLai Jiangshan1-2/+1
Currently, the .exp_hint flag is cleared in rcu_read_unlock_special(), which works, but which can also prevent subsequent rcu_read_unlock() calls from helping expedite the quiescent state needed by an ongoing expedited RCU grace period. This commit therefore defers clearing of .exp_hint from rcu_read_unlock_special() to rcu_preempt_deferred_qs_irqrestore(), thus ensuring that intervening calls to rcu_read_unlock() have a chance to help end the expedited grace period. Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Rename some instance of CONFIG_PREEMPTION to CONFIG_PREEMPT_RCULai Jiangshan2-5/+5
CONFIG_PREEMPTION and CONFIG_PREEMPT_RCU are always identical, but some code depends on CONFIG_PREEMPTION to access to rcu_preempt functionality. This patch changes CONFIG_PREEMPTION to CONFIG_PREEMPT_RCU in these cases. Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Remove kfree_call_rcu_nobatch()Joel Fernandes (Google)2-23/+5
Now that the kfree_rcu() special-casing has been removed from tree RCU, this commit removes kfree_call_rcu_nobatch() since it is no longer needed. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Remove kfree_rcu() special casing and lazy-callback handlingJoel Fernandes (Google)9-129/+75
This commit removes kfree_rcu() special-casing and the lazy-callback handling from Tree RCU. It moves some of this special casing to Tiny RCU, the removal of which will be the subject of later commits. This results in a nice negative delta. Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> [ paulmck: Add slab.h #include, thanks to kbuild test robot <lkp@intel.com>. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Add support for debug_objects debugging for kfree_rcu()Joel Fernandes (Google)1-0/+8
This commit applies RCU's debug_objects debugging to the new batched kfree_rcu() implementations. The object is queued at the kfree_rcu() call and dequeued during reclaim. Tested that enabling CONFIG_DEBUG_OBJECTS_RCU_HEAD successfully detects double kfree_rcu() calls. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> [ paulmck: Fix IRQ per kbuild test robot <lkp@intel.com> feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Add multiple in-flight batches of kfree_rcu() workJoel Fernandes (Google)1-12/+39
During testing, it was observed that amount of memory consumed due kfree_rcu() batching is 300-400MB. Previously we had only a single head_free pointer pointing to the list of rcu_head(s) that are to be freed after a grace period. Until this list is drained, we cannot queue any more objects on it since such objects may not be ready to be reclaimed when the worker thread eventually gets to drainin g the head_free list. We can do better by maintaining multiple lists as done by this patch. Testing shows that memory consumption came down by around 100-150MB with just adding another list. Adding more than 1 additional list did not show any improvement. Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> [ paulmck: Code style and initialization handling. ] [ paulmck: Fix field name, reported by kbuild test robot <lkp@intel.com>. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Make kfree_rcu() use a non-atomic ->monitor_todoJoel Fernandes1-6/+10
Because the ->monitor_todo field is always protected by krcp->lock, this commit downgrades from xchg() to non-atomic unmarked assignment statements. Signed-off-by: Joel Fernandes <joel@joelfernandes.org> [ paulmck: Update to include early-boot kick code. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcuperf: Add kfree_rcu() performance TestsJoel Fernandes (Google)1-8/+173
This test runs kfree_rcu() in a loop to measure performance of the new kfree_rcu() batching functionality. The following table shows results when booting with arguments: rcuperf.kfree_loops=20000 rcuperf.kfree_alloc_num=8000 rcuperf.kfree_rcu_test=1 rcuperf.kfree_no_batch=X rcuperf.kfree_no_batch=X # Grace Periods Test Duration (s) X=1 (old behavior) 9133 11.5 X=0 (new behavior) 1732 12.5 On a 16 CPU system with the above boot parameters, we see that the total number of grace periods that elapse during the test drops from 9133 when not batching to 1732 when batching (a 5X improvement). The kfree_rcu() flood itself slows down a bit when batching, though, as shown. Note that the active memory consumption during the kfree_rcu() flood does increase to around 200-250MB due to the batching (from around 50MB without batching). However, this memory consumption is relatively constant. In other words, the system is able to keep up with the kfree_rcu() load. The memory consumption comes down considerably if KFREE_DRAIN_JIFFIES is increased from HZ/50 to HZ/80. A later patch will reduce memory consumption further by using multiple lists. Also, when running the test, please disable CONFIG_DEBUG_PREEMPT and CONFIG_PROVE_RCU for realistic comparisons with/without batching. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-24rcu: Add basic support for kfree_rcu() batchingByungchul Park2-6/+198
Recently a discussion about stability and performance of a system involving a high rate of kfree_rcu() calls surfaced on the list [1] which led to another discussion how to prepare for this situation. This patch adds basic batching support for kfree_rcu(). It is "basic" because we do none of the slab management, dynamic allocation, code moving or any of the other things, some of which previous attempts did [2]. These fancier improvements can be follow-up patches and there are different ideas being discussed in those regards. This is an effort to start simple, and build up from there. In the future, an extension to use kfree_bulk and possibly per-slab batching could be done to further improve performance due to cache-locality and slab-specific bulk free optimizations. By using an array of pointers, the worker thread processing the work would need to read lesser data since it does not need to deal with large rcu_head(s) any longer. Torture tests follow in the next patch and show improvements of around 5x reduction in number of grace periods on a 16 CPU system. More details and test data are in that patch. There is an implication with rcu_barrier() with this patch. Since the kfree_rcu() calls can be batched, and may not be handed yet to the RCU machinery in fact, the monitor may not have even run yet to do the queue_rcu_work(), there seems no easy way of implementing rcu_barrier() to wait for those kfree_rcu()s that are already made. So this means a kfree_rcu() followed by an rcu_barrier() does not imply that memory will be freed once rcu_barrier() returns. Another implication is higher active memory usage (although not run-away..) until the kfree_rcu() flooding ends, in comparison to without batching. More details about this are in the second patch which adds an rcuperf test. Finally, in the near future we will get rid of kfree_rcu() special casing within RCU such as in rcu_do_batch and switch everything to just batching. Currently we don't do that since timer subsystem is not yet up and we cannot schedule the kfree_rcu() monitor as the timer subsystem's lock are not initialized. That would also mean getting rid of kfree_call_rcu_nobatch() entirely. [1] http://lore.kernel.org/lkml/20190723035725-mutt-send-email-mst@kernel.org [2] https://lkml.org/lkml/2017/12/19/824 Cc: kernel-team@android.com Cc: kernel-team@lge.com Co-developed-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> [ paulmck: Applied 0day and Paul Walmsley feedback on ->monitor_todo. ] [ paulmck: Make it work during early boot. ] [ paulmck: Add a crude early boot self-test. ] [ paulmck: Style adjustments and experimental docbook structure header. ] Link: https://lore.kernel.org/lkml/alpine.DEB.2.21.9999.1908161931110.32497@viisi.sifive.com/T/#me9956f66cb611b95d26ae92700e1d901f46e8c59 Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-23Merge tag 'trace-v5.5-rc6-2' of ↵Linus Torvalds7-70/+158
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Various tracing fixes: - Fix a function comparison warning for a xen trace event macro - Fix a double perf_event linking to a trace_uprobe_filter for multiple events - Fix suspicious RCU warnings in trace event code for using list_for_each_entry_rcu() when the "_rcu" portion wasn't needed. - Fix a bug in the histogram code when using the same variable - Fix a NULL pointer dereference when tracefs lockdown enabled and calling trace_set_default_clock() - A fix to a bug found with the double perf_event linking patch" * tag 'trace-v5.5-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/uprobe: Fix to make trace_uprobe_filter alignment safe tracing: Do not set trace clock if tracefs lockdown is in effect tracing: Fix histogram code when expression has same var as value tracing: trigger: Replace unneeded RCU-list traversals tracing/uprobe: Fix double perf_event linking on multiprobe uprobe tracing: xen: Ordered comparison of function pointers
2020-01-23Merge tag 'pm-5.5-rc8' of ↵Linus Torvalds1-10/+10
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fix from Rafael Wysocki: "Prevent the kernel from crashing during resume from hibernation if free pages contain leftover data from the restore kernel and init_on_free is set (Alexander Potapenko)" * tag 'pm-5.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM: hibernate: fix crashes with init_on_free=1