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* | Merge tag 'sched-core-2022-05-23' of ↵Linus Torvalds2022-05-241-14/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - Updates to scheduler metrics: - PELT fixes & enhancements - PSI fixes & enhancements - Refactor cpu_util_without() - Updates to instrumentation/debugging: - Remove sched_trace_*() helper functions - can be done via debug info - Fix double update_rq_clock() warnings - Introduce & use "preemption model accessors" to simplify some of the Kconfig complexity. - Make softirq handling RT-safe. - Misc smaller fixes & cleanups. * tag 'sched-core-2022-05-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: topology: Remove unused cpu_cluster_mask() sched: Reverse sched_class layout sched/deadline: Remove superfluous rq clock update in push_dl_task() sched/core: Avoid obvious double update_rq_clock warning smp: Make softirq handling RT safe in flush_smp_call_function_queue() smp: Rename flush_smp_call_function_from_idle() sched: Fix missing prototype warnings sched/fair: Remove cfs_rq_tg_path() sched/fair: Remove sched_trace_*() helper functions sched/fair: Refactor cpu_util_without() sched/fair: Revise comment about lb decision matrix sched/psi: report zeroes for CPU full at the system level sched/fair: Delete useless condition in tg_unthrottle_up() sched/fair: Fix cfs_rq_clock_pelt() for throttled cfs_rq sched/fair: Move calculate of avg_load to a better location mailmap: Update my email address to @redhat.com MAINTAINERS: Add myself as scheduler topology reviewer psi: Fix trigger being fired unexpectedly at initial ftrace: Use preemption model accessors for trace header printout kcsan: Use preemption model accessors
| * \ Merge tag 'v5.18-rc5' into sched/core to pull in fixes & to resolve a conflictIngo Molnar2022-05-061-0/+1
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - sched/core is on a pretty old -rc1 base - refresh it to include recent fixes. - this also allows up to resolve a (trivial) .mailmap conflict Conflicts: .mailmap Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched: Fix missing prototype warningsThomas Gleixner2022-05-011-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A W=1 build emits more than a dozen missing prototype warnings related to scheduler and scheduler specific includes. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220413133024.249118058@linutronix.de
| * | | sched/fair: Remove sched_trace_*() helper functionsDietmar Eggemann2022-04-291-14/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We no longer need them as we can use DWARF debug info or BTF + pahole to re-generate the required structs to compile against them for a given kernel. This moves the burden of maintaining these helper functions to the module. https://github.com/qais-yousef/sched_tp Note that pahole v1.15 is required at least for using DWARF. And for BTF v1.23 which is not yet released will be required. There's alignment problem that will lead to crashes in earlier versions when used with BTF. We should have enough infrastructure to make these helper functions now obsolete, so remove them. [Rewrote commit message to reflect the new alternative] Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220428144338.479094-2-qais.yousef@arm.com
* | | | Merge tag 'x86_splitlock_for_v5.19_rc1' of ↵Linus Torvalds2022-05-231-0/+3
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 splitlock updates from Borislav Petkov: - Add Raptor Lake to the set of CPU models which support splitlock - Make life miserable for apps using split locks by slowing them down considerably while the rest of the system remains responsive. The hope is it will hurt more and people will really fix their misaligned locks apps. As a result, free a TIF bit. * tag 'x86_splitlock_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/split_lock: Enable the split lock feature on Raptor Lake x86/split-lock: Remove unused TIF_SLD bit x86/split_lock: Make life miserable for split lockers
| * | | | x86/split_lock: Make life miserable for split lockersTony Luck2022-04-271-0/+3
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In https://lore.kernel.org/all/87y22uujkm.ffs@tglx/ Thomas said: Its's simply wishful thinking that stuff gets fixed because of a WARN_ONCE(). This has never worked. The only thing which works is to make stuff fail hard or slow it down in a way which makes it annoying enough to users to complain. He was talking about WBINVD. But it made me think about how we use the split lock detection feature in Linux. Existing code has three options for applications: 1) Don't enable split lock detection (allow arbitrary split locks) 2) Warn once when a process uses split lock, but let the process keep running with split lock detection disabled 3) Kill process that use split locks Option 2 falls into the "wishful thinking" territory that Thomas warns does nothing. But option 3 might not be viable in a situation with legacy applications that need to run. Hence make option 2 much stricter to "slow it down in a way which makes it annoying". Primary reason for this change is to provide better quality of service to the rest of the applications running on the system. Internal testing shows that even with many processes splitting locks, performance for the rest of the system is much more responsive. The new "warn" mode operates like this. When an application tries to execute a bus lock the #AC handler. 1) Delays (interruptibly) 10 ms before moving to next step. 2) Blocks (interruptibly) until it can get the semaphore If interrupted, just return. Assume the signal will either kill the task, or direct execution away from the instruction that is trying to get the bus lock. 3) Disables split lock detection for the current core 4) Schedules a work queue to re-enable split lock detect in 2 jiffies 5) Returns The work queue that re-enables split lock detection also releases the semaphore. There is a corner case where a CPU may be taken offline while split lock detection is disabled. A CPU hotplug handler handles this case. Old behaviour was to only print the split lock warning on the first occurrence of a split lock from a task. Preserve that by adding a flag to the task structure that suppresses subsequent split lock messages from that task. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220310204854.31752-2-tony.luck@intel.com
* | | | Merge tag 'rcu.2022.05.19a' of ↵Linus Torvalds2022-05-231-0/+41
|\ \ \ \ | |/ / / |/| / / | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull RCU update from Paul McKenney: - Documentation updates - Miscellaneous fixes - Callback-offloading updates, mainly simplifications - RCU-tasks updates, including some -rt fixups, handling of systems with sparse CPU numbering, and a fix for a boot-time race-condition failure - Put SRCU on a memory diet in order to reduce the size of the srcu_struct structure - Torture-test updates fixing some bugs in tests and closing some testing holes - Torture-test updates for the RCU tasks flavors, most notably ensuring that building rcutorture and friends does not change the RCU-tasks-related Kconfig options - Torture-test scripting updates - Expedited grace-period updates, most notably providing milliseconds-scale (not all that) soft real-time response from synchronize_rcu_expedited(). This is also the first time in almost 30 years of RCU that someone other than me has pushed for a reduction in the RCU CPU stall-warning timeout, in this case by more than three orders of magnitude from 21 seconds to 20 milliseconds. This tighter timeout applies only to expedited grace periods * tag 'rcu.2022.05.19a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (80 commits) rcu: Move expedited grace period (GP) work to RT kthread_worker rcu: Introduce CONFIG_RCU_EXP_CPU_STALL_TIMEOUT srcu: Drop needless initialization of sdp in srcu_gp_start() srcu: Prevent expedited GPs and blocking readers from consuming CPU srcu: Add contention check to call_srcu() srcu_data ->lock acquisition srcu: Automatically determine size-transition strategy at boot rcutorture: Make torture.sh allow for --kasan rcutorture: Make torture.sh refscale and rcuscale specify Tasks Trace RCU rcutorture: Make kvm.sh allow more memory for --kasan runs torture: Save "make allmodconfig" .config file scftorture: Remove extraneous "scf" from per_version_boot_params rcutorture: Adjust scenarios' Kconfig options for CONFIG_PREEMPT_DYNAMIC torture: Enable CSD-lock stall reports for scftorture torture: Skip vmlinux check for kvm-again.sh runs scftorture: Adjust for TASKS_RCU Kconfig option being selected rcuscale: Allow rcuscale without RCU Tasks Rude/Trace rcuscale: Allow rcuscale without RCU Tasks refscale: Allow refscale without RCU Tasks Rude/Trace refscale: Allow refscale without RCU Tasks rcutorture: Allow specifying per-scenario stat_interval ...
| * / preempt/dynamic: Introduce preemption model accessorsValentin Schneider2022-04-051-0/+41
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_PREEMPT{_NONE, _VOLUNTARY} designate either: o The build-time preemption model when !PREEMPT_DYNAMIC o The default boot-time preemption model when PREEMPT_DYNAMIC IOW, using those on PREEMPT_DYNAMIC kernels is meaningless - the actual model could have been set to something else by the "preempt=foo" cmdline parameter. Same problem applies to CONFIG_PREEMPTION. Introduce a set of helpers to determine the actual preemption model used by the live kernel. Suggested-by: Marco Elver <elver@google.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Marco Elver <elver@google.com> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20211112185203.280040-3-valentin.schneider@arm.com
* / oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanupNico Pache2022-04-211-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pthread struct is allocated on PRIVATE|ANONYMOUS memory [1] which can be targeted by the oom reaper. This mapping is used to store the futex robust list head; the kernel does not keep a copy of the robust list and instead references a userspace address to maintain the robustness during a process death. A race can occur between exit_mm and the oom reaper that allows the oom reaper to free the memory of the futex robust list before the exit path has handled the futex death: CPU1 CPU2 -------------------------------------------------------------------- page_fault do_exit "signal" wake_oom_reaper oom_reaper oom_reap_task_mm (invalidates mm) exit_mm exit_mm_release futex_exit_release futex_cleanup exit_robust_list get_user (EFAULT- can't access memory) If the get_user EFAULT's, the kernel will be unable to recover the waiters on the robust_list, leaving userspace mutexes hung indefinitely. Delay the OOM reaper, allowing more time for the exit path to perform the futex cleanup. Reproducer: https://gitlab.com/jsavitz/oom_futex_reproducer Based on a patch by Michal Hocko. Link: https://elixir.bootlin.com/glibc/glibc-2.35/source/nptl/allocatestack.c#L370 [1] Link: https://lkml.kernel.org/r/20220414144042.677008-1-npache@redhat.com Fixes: 212925802454 ("mm: oom: let oom_reap_task and exit_mmap run concurrently") Signed-off-by: Joel Savitz <jsavitz@redhat.com> Signed-off-by: Nico Pache <npache@redhat.com> Co-developed-by: Joel Savitz <jsavitz@redhat.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Waiman Long <longman@redhat.com> Cc: Herton R. Krzesinski <herton@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ben Segall <bsegall@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Savitz <jsavitz@redhat.com> Cc: Darren Hart <dvhart@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels"Thomas Gleixner2022-03-311-3/+0
| | | | | | | | | | Revert commit bf9ad37dc8a. It needs to be better encapsulated and generalized. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
* Merge tag 'net-next-5.18' of ↵Linus Torvalds2022-03-241-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "The sprinkling of SPI drivers is because we added a new one and Mark sent us a SPI driver interface conversion pull request. Core ---- - Introduce XDP multi-buffer support, allowing the use of XDP with jumbo frame MTUs and combination with Rx coalescing offloads (LRO). - Speed up netns dismantling (5x) and lower the memory cost a little. Remove unnecessary per-netns sockets. Scope some lists to a netns. Cut down RCU syncing. Use batch methods. Allow netdev registration to complete out of order. - Support distinguishing timestamp types (ingress vs egress) and maintaining them across packet scrubbing points (e.g. redirect). - Continue the work of annotating packet drop reasons throughout the stack. - Switch netdev error counters from an atomic to dynamically allocated per-CPU counters. - Rework a few preempt_disable(), local_irq_save() and busy waiting sections problematic on PREEMPT_RT. - Extend the ref_tracker to allow catching use-after-free bugs. BPF --- - Introduce "packing allocator" for BPF JIT images. JITed code is marked read only, and used to be allocated at page granularity. Custom allocator allows for more efficient memory use, lower iTLB pressure and prevents identity mapping huge pages from getting split. - Make use of BTF type annotations (e.g. __user, __percpu) to enforce the correct probe read access method, add appropriate helpers. - Convert the BPF preload to use light skeleton and drop the user-mode-driver dependency. - Allow XDP BPF_PROG_RUN test infra to send real packets, enabling its use as a packet generator. - Allow local storage memory to be allocated with GFP_KERNEL if called from a hook allowed to sleep. - Introduce fprobe (multi kprobe) to speed up mass attachment (arch bits to come later). - Add unstable conntrack lookup helpers for BPF by using the BPF kfunc infra. - Allow cgroup BPF progs to return custom errors to user space. - Add support for AF_UNIX iterator batching. - Allow iterator programs to use sleepable helpers. - Support JIT of add, and, or, xor and xchg atomic ops on arm64. - Add BTFGen support to bpftool which allows to use CO-RE in kernels without BTF info. - Large number of libbpf API improvements, cleanups and deprecations. Protocols --------- - Micro-optimize UDPv6 Tx, gaining up to 5% in test on dummy netdev. - Adjust TSO packet sizes based on min_rtt, allowing very low latency links (data centers) to always send full-sized TSO super-frames. - Make IPv6 flow label changes (AKA hash rethink) more configurable, via sysctl and setsockopt. Distinguish between server and client behavior. - VxLAN support to "collect metadata" devices to terminate only configured VNIs. This is similar to VLAN filtering in the bridge. - Support inserting IPv6 IOAM information to a fraction of frames. - Add protocol attribute to IP addresses to allow identifying where given address comes from (kernel-generated, DHCP etc.) - Support setting socket and IPv6 options via cmsg on ping6 sockets. - Reject mis-use of ECN bits in IP headers as part of DSCP/TOS. Define dscp_t and stop taking ECN bits into account in fib-rules. - Add support for locked bridge ports (for 802.1X). - tun: support NAPI for packets received from batched XDP buffs, doubling the performance in some scenarios. - IPv6 extension header handling in Open vSwitch. - Support IPv6 control message load balancing in bonding, prevent neighbor solicitation and advertisement from using the wrong port. Support NS/NA monitor selection similar to existing ARP monitor. - SMC - improve performance with TCP_CORK and sendfile() - support auto-corking - support TCP_NODELAY - MCTP (Management Component Transport Protocol) - add user space tag control interface - I2C binding driver (as specified by DMTF DSP0237) - Multi-BSSID beacon handling in AP mode for WiFi. - Bluetooth: - handle MSFT Monitor Device Event - add MGMT Adv Monitor Device Found/Lost events - Multi-Path TCP: - add support for the SO_SNDTIMEO socket option - lots of selftest cleanups and improvements - Increase the max PDU size in CAN ISOTP to 64 kB. Driver API ---------- - Add HW counters for SW netdevs, a mechanism for devices which offload packet forwarding to report packet statistics back to software interfaces such as tunnels. - Select the default NIC queue count as a fraction of number of physical CPU cores, instead of hard-coding to 8. - Expose devlink instance locks to drivers. Allow device layer of drivers to use that lock directly instead of creating their own which always runs into ordering issues in devlink callbacks. - Add header/data split indication to guide user space enabling of TCP zero-copy Rx. - Allow configuring completion queue event size. - Refactor page_pool to enable fragmenting after allocation. - Add allocation and page reuse statistics to page_pool. - Improve Multiple Spanning Trees support in the bridge to allow reuse of topologies across VLANs, saving HW resources in switches. - DSA (Distributed Switch Architecture): - replay and offload of host VLAN entries - offload of static and local FDB entries on LAG interfaces - FDB isolation and unicast filtering New hardware / drivers ---------------------- - Ethernet: - LAN937x T1 PHYs - Davicom DM9051 SPI NIC driver - Realtek RTL8367S, RTL8367RB-VB switch and MDIO - Microchip ksz8563 switches - Netronome NFP3800 SmartNICs - Fungible SmartNICs - MediaTek MT8195 switches - WiFi: - mt76: MediaTek mt7916 - mt76: MediaTek mt7921u USB adapters - brcmfmac: Broadcom BCM43454/6 - Mobile: - iosm: Intel M.2 7360 WWAN card Drivers ------- - Convert many drivers to the new phylink API built for split PCS designs but also simplifying other cases. - Intel Ethernet NICs: - add TTY for GNSS module for E810T device - improve AF_XDP performance - GTP-C and GTP-U filter offload - QinQ VLAN support - Mellanox Ethernet NICs (mlx5): - support xdp->data_meta - multi-buffer XDP - offload tc push_eth and pop_eth actions - Netronome Ethernet NICs (nfp): - flow-independent tc action hardware offload (police / meter) - AF_XDP - Other Ethernet NICs: - at803x: fiber and SFP support - xgmac: mdio: preamble suppression and custom MDC frequencies - r8169: enable ASPM L1.2 if system vendor flags it as safe - macb/gem: ZynqMP SGMII - hns3: add TX push mode - dpaa2-eth: software TSO - lan743x: multi-queue, mdio, SGMII, PTP - axienet: NAPI and GRO support - Mellanox Ethernet switches (mlxsw): - source and dest IP address rewrites - RJ45 ports - Marvell Ethernet switches (prestera): - basic routing offload - multi-chain TC ACL offload - NXP embedded Ethernet switches (ocelot & felix): - PTP over UDP with the ocelot-8021q DSA tagging protocol - basic QoS classification on Felix DSA switch using dcbnl - port mirroring for ocelot switches - Microchip high-speed industrial Ethernet (sparx5): - offloading of bridge port flooding flags - PTP Hardware Clock - Other embedded switches: - lan966x: PTP Hardward Clock - qca8k: mdio read/write operations via crafted Ethernet packets - Qualcomm 802.11ax WiFi (ath11k): - add LDPC FEC type and 802.11ax High Efficiency data in radiotap - enable RX PPDU stats in monitor co-exist mode - Intel WiFi (iwlwifi): - UHB TAS enablement via BIOS - band disablement via BIOS - channel switch offload - 32 Rx AMPDU sessions in newer devices - MediaTek WiFi (mt76): - background radar detection - thermal management improvements on mt7915 - SAR support for more mt76 platforms - MBSSID and 6 GHz band on mt7915 - RealTek WiFi: - rtw89: AP mode - rtw89: 160 MHz channels and 6 GHz band - rtw89: hardware scan - Bluetooth: - mt7921s: wake on Bluetooth, SCO over I2S, wide-band-speed (WBS) - Microchip CAN (mcp251xfd): - multiple RX-FIFOs and runtime configurable RX/TX rings - internal PLL, runtime PM handling simplification - improve chip detection and error handling after wakeup" * tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2521 commits) llc: fix netdevice reference leaks in llc_ui_bind() drivers: ethernet: cpsw: fix panic when interrupt coaleceing is set via ethtool ice: don't allow to run ice_send_event_to_aux() in atomic ctx ice: fix 'scheduling while atomic' on aux critical err interrupt net/sched: fix incorrect vlan_push_eth dest field net: bridge: mst: Restrict info size queries to bridge ports net: marvell: prestera: add missing destroy_workqueue() in prestera_module_init() drivers: net: xgene: Fix regression in CRC stripping net: geneve: add missing netlink policy and size for IFLA_GENEVE_INNER_PROTO_INHERIT net: dsa: fix missing host-filtered multicast addresses net/mlx5e: Fix build warning, detected write beyond size of field iwlwifi: mvm: Don't fail if PPAG isn't supported selftests/bpf: Fix kprobe_multi test. Revert "rethook: x86: Add rethook x86 implementation" Revert "arm64: rethook: Add arm64 rethook implementation" Revert "powerpc: Add rethook support" Revert "ARM: rethook: Add rethook arm implementation" netdevice: add missing dm_private kdoc net: bridge: mst: prevent NULL deref in br_mst_info_size() selftests: forwarding: Use same VRF for port and VLAN upper ...
| * rethook: Add a generic return hookMasami Hiramatsu2022-03-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a return hook framework which hooks the function return. Most of the logic came from the kretprobe, but this is independent from kretprobe. Note that this is expected to be used with other function entry hooking feature, like ftrace, fprobe, adn kprobes. Eventually this will replace the kretprobe (e.g. kprobe + rethook = kretprobe), but at this moment, this is just an additional hook. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/164735285066.1084943.9259661137330166643.stgit@devnote2
* | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2022-03-221-1/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge updates from Andrew Morton: - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs - Most the MM patches which precede the patches in Willy's tree: kasan, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb, userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp, cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap, zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits) mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release() Docs/ABI/testing: add DAMON sysfs interface ABI document Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface selftests/damon: add a test for DAMON sysfs interface mm/damon/sysfs: support DAMOS stats mm/damon/sysfs: support DAMOS watermarks mm/damon/sysfs: support schemes prioritization mm/damon/sysfs: support DAMOS quotas mm/damon/sysfs: support DAMON-based Operation Schemes mm/damon/sysfs: support the physical address space monitoring mm/damon/sysfs: link DAMON for virtual address spaces monitoring mm/damon: implement a minimal stub for sysfs-based DAMON interface mm/damon/core: add number of each enum type values mm/damon/core: allow non-exclusive DAMON start/stop Docs/damon: update outdated term 'regions update interval' Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling Docs/vm/damon: call low level monitoring primitives the operations mm/damon: remove unnecessary CONFIG_DAMON option mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}() mm/damon/dbgfs-test: fix is_target_id() change ...
| * | mm/fs: delete PF_SWAPWRITEHugh Dickins2022-03-221-1/+0
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PF_SWAPWRITE has been redundant since v3.2 commit ee72886d8ed5 ("mm: vmscan: do not writeback filesystem pages in direct reclaim"). Coincidentally, NeilBrown's current patch "remove inode_congested()" deletes may_write_to_inode(), which appeared to be the one function which took notice of PF_SWAPWRITE. But if you study the old logic, and the conditions under which may_write_to_inode() was called, you discover that flag and function have been pointless for a decade. Link: https://lkml.kernel.org/r/75e80e7-742d-e3bd-531-614db8961e4@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: NeilBrown <neilb@suse.de> Cc: Jan Kara <jack@suse.de> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'sched-core-2022-03-22' of ↵Linus Torvalds2022-03-221-4/+25
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * | sched/tracing: Report TASK_RTLOCK_WAIT tasks as TASK_UNINTERRUPTIBLEValentin Schneider2022-03-011-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TASK_RTLOCK_WAIT currently isn't part of TASK_REPORT, thus a task blocking on an rtlock will appear as having a task state == 0, IOW TASK_RUNNING. The actual state is saved in p->saved_state, but reading it after reading p->__state has a few issues: o that could still be TASK_RUNNING in the case of e.g. rt_spin_lock o ttwu_state_match() might have changed that to TASK_RUNNING As pointed out by Eric, adding TASK_RTLOCK_WAIT to TASK_REPORT implies exposing a new state to userspace tools which way not know what to do with them. The only information that needs to be conveyed here is that a task is waiting on an rt_mutex, which matches TASK_UNINTERRUPTIBLE - there's no need for a new state. Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20220120162520.570782-3-valentin.schneider@arm.com
| * | sched/tracing: Don't re-read p->state when emitting sched_switch eventValentin Schneider2022-03-011-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As of commit c6e7bd7afaeb ("sched/core: Optimize ttwu() spinning on p->on_cpu") the following sequence becomes possible: p->__state = TASK_INTERRUPTIBLE; __schedule() deactivate_task(p); ttwu() READ !p->on_rq p->__state=TASK_WAKING trace_sched_switch() __trace_sched_switch_state() task_state_index() return 0; TASK_WAKING isn't in TASK_REPORT, so the task appears as TASK_RUNNING in the trace event. Prevent this by pushing the value read from __schedule() down the trace event. Reported-by: Abhijeet Dharmapurikar <adharmap@quicinc.com> Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20220120162520.570782-2-valentin.schneider@arm.com
| * | Merge tag 'v5.17-rc5' into sched/core, to resolve conflictsIngo Molnar2022-02-211-5/+0
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | New conflicts in sched/core due to the following upstream fixes: 44585f7bc0cb ("psi: fix "defined but not used" warnings when CONFIG_PROC_FS=n") a06247c6804f ("psi: Fix uaf issue when psi trigger is destroyed while being polled") Conflicts: include/linux/psi_types.h kernel/sched/psi.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | sched/preempt: Add PREEMPT_DYNAMIC using static keysMark Rutland2022-02-191-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Where an architecture selects HAVE_STATIC_CALL but not HAVE_STATIC_CALL_INLINE, each static call has an out-of-line trampoline which will either branch to a callee or return to the caller. On such architectures, a number of constraints can conspire to make those trampolines more complicated and potentially less useful than we'd like. For example: * Hardware and software control flow integrity schemes can require the addition of "landing pad" instructions (e.g. `BTI` for arm64), which will also be present at the "real" callee. * Limited branch ranges can require that trampolines generate or load an address into a register and perform an indirect branch (or at least have a slow path that does so). This loses some of the benefits of having a direct branch. * Interaction with SW CFI schemes can be complicated and fragile, e.g. requiring that we can recognise idiomatic codegen and remove indirections understand, at least until clang proves more helpful mechanisms for dealing with this. For PREEMPT_DYNAMIC, we don't need the full power of static calls, as we really only need to enable/disable specific preemption functions. We can achieve the same effect without a number of the pain points above by using static keys to fold early returns into the preemption functions themselves rather than in an out-of-line trampoline, effectively inlining the trampoline into the start of the function. For arm64, this results in good code generation. For example, the dynamic_cond_resched() wrapper looks as follows when enabled. When disabled, the first `B` is replaced with a `NOP`, resulting in an early return. | <dynamic_cond_resched>: | bti c | b <dynamic_cond_resched+0x10> // or `nop` | mov w0, #0x0 | ret | mrs x0, sp_el0 | ldr x0, [x0, #8] | cbnz x0, <dynamic_cond_resched+0x8> | paciasp | stp x29, x30, [sp, #-16]! | mov x29, sp | bl <preempt_schedule_common> | mov w0, #0x1 | ldp x29, x30, [sp], #16 | autiasp | ret ... compared to the regular form of the function: | <__cond_resched>: | bti c | mrs x0, sp_el0 | ldr x1, [x0, #8] | cbz x1, <__cond_resched+0x18> | mov w0, #0x0 | ret | paciasp | stp x29, x30, [sp, #-16]! | mov x29, sp | bl <preempt_schedule_common> | mov w0, #0x1 | ldp x29, x30, [sp], #16 | autiasp | ret Any architecture which implements static keys should be able to use this to implement PREEMPT_DYNAMIC with similar cost to non-inlined static calls. Since this is likely to have greater overhead than (inlined) static calls, PREEMPT_DYNAMIC is only defaulted to enabled when HAVE_PREEMPT_DYNAMIC_CALL is selected. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20220214165216.2231574-6-mark.rutland@arm.com
* | | Merge tag 'core-core-2022-03-21' of ↵Linus Torvalds2022-03-211-0/+3
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core process handling RT latency updates from Thomas Gleixner: - Reduce the amount of work to release a task stack in context switch. There is no real reason to do cgroup accounting and memory freeing in this performance sensitive context. Aside of this the invoked functions cannot be called from this preemption disabled context on PREEMPT_RT enabled kernels. Solve this by moving the accounting into do_exit() and delaying the freeing of the stack unless the vmap stack can be cached. - Provide a mechanism to delay raising signals from atomic context on PREEMPT_RT enabled kernels as sighand::lock cannot be acquired. Store the information in the task struct and raise it in the exit path. * tag 'core-core-2022-03-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: signal, x86: Delay calling signals in atomic on RT enabled kernels fork: Use IS_ENABLED() in account_kernel_stack() fork: Only cache the VMAP stack in finish_task_switch() fork: Move task stack accounting to do_exit() fork: Move memcg_charge_kernel_stack() into CONFIG_VMAP_STACK fork: Don't assign the stack pointer in dup_task_struct() fork, IA64: Provide alloc_thread_stack_node() for IA64 fork: Duplicate task_struct before stack allocation fork: Redo ifdefs around task stack handling
| * | | signal, x86: Delay calling signals in atomic on RT enabled kernelsOleg Nesterov2022-03-041-0/+3
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86_64 we must disable preemption before we enable interrupts for stack faults, int3 and debugging, because the current task is using a per CPU debug stack defined by the IST. If we schedule out, another task can come in and use the same stack and cause the stack to be corrupted and crash the kernel on return. When CONFIG_PREEMPT_RT is enabled, spinlock_t locks become sleeping, and one of these is the spin lock used in signal handling. Some of the debug code (int3) causes do_trap() to send a signal. This function calls a spinlock_t lock that has been converted to a sleeping lock. If this happens, the above issues with the corrupted stack is possible. Instead of calling the signal right away, for PREEMPT_RT and x86, the signal information is stored on the stacks task_struct and TIF_NOTIFY_RESUME is set. Then on exit of the trap, the signal resume code will send the signal when preemption is enabled. [ rostedt: Switched from #ifdef CONFIG_PREEMPT_RT to ARCH_RT_DELAYS_SIGNAL_SEND and added comments to the code. ] [bigeasy: Add on 32bit as per Yang Shi, minor rewording. ] [ tglx: Use a config option ] Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/Ygq5aBB/qMQw6aP5@linutronix.de
* / | sched: Define and initialize a flag to identify valid PASID in the taskPeter Zijlstra2022-02-151-0/+3
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new single bit field to the task structure to track whether this task has initialized the IA32_PASID MSR to the mm's PASID. Initialize the field to zero when creating a new task with fork/clone. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Co-developed-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220207230254.3342514-8-fenghua.yu@intel.com
* | Revert "module, async: async_synchronize_full() on module init iff async is ↵Igor Pylypiv2022-02-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | used" This reverts commit 774a1221e862b343388347bac9b318767336b20b. We need to finish all async code before the module init sequence is done. In the reverted commit the PF_USED_ASYNC flag was added to mark a thread that called async_schedule(). Then the PF_USED_ASYNC flag was used to determine whether or not async_synchronize_full() needs to be invoked. This works when modprobe thread is calling async_schedule(), but it does not work if module dispatches init code to a worker thread which then calls async_schedule(). For example, PCI driver probing is invoked from a worker thread based on a node where device is attached: if (cpu < nr_cpu_ids) error = work_on_cpu(cpu, local_pci_probe, &ddi); else error = local_pci_probe(&ddi); We end up in a situation where a worker thread gets the PF_USED_ASYNC flag set instead of the modprobe thread. As a result, async_synchronize_full() is not invoked and modprobe completes without waiting for the async code to finish. The issue was discovered while loading the pm80xx driver: (scsi_mod.scan=async) modprobe pm80xx worker ... do_init_module() ... pci_call_probe() work_on_cpu(local_pci_probe) local_pci_probe() pm8001_pci_probe() scsi_scan_host() async_schedule() worker->flags |= PF_USED_ASYNC; ... < return from worker > ... if (current->flags & PF_USED_ASYNC) <--- false async_synchronize_full(); Commit 21c3c5d28007 ("block: don't request module during elevator init") fixed the deadlock issue which the reverted commit 774a1221e862 ("module, async: async_synchronize_full() on module init iff async is used") tried to fix. Since commit 0fdff3ec6d87 ("async, kmod: warn on synchronous request_module() from async workers") synchronous module loading from async is not allowed. Given that the original deadlock issue is fixed and it is no longer allowed to call synchronous request_module() from async we can remove PF_USED_ASYNC flag to make module init consistently invoke async_synchronize_full() unless async module probe is requested. Signed-off-by: Igor Pylypiv <ipylypiv@google.com> Reviewed-by: Changyuan Lyu <changyuanl@google.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'sched_urgent_for_v5.17_rc2' of ↵Linus Torvalds2022-01-231-4/+0
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Borislav Petkov: "A bunch of fixes: forced idle time accounting, utilization values propagation in the sched hierarchies and other minor cleanups and improvements" * tag 'sched_urgent_for_v5.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kernel/sched: Remove dl_boosted flag comment sched: Avoid double preemption in __cond_resched_*lock*() sched/fair: Fix all kernel-doc warnings sched/core: Accounting forceidle time for all tasks except idle task sched/pelt: Relax the sync of load_sum with load_avg sched/pelt: Relax the sync of runnable_sum with runnable_avg sched/pelt: Continue to relax the sync of util_sum with util_avg sched/pelt: Relax the sync of util_sum with util_avg psi: Fix uaf issue when psi trigger is destroyed while being polled
| * kernel/sched: Remove dl_boosted flag commentHui Su2022-01-181-4/+0
| | | | | | | | | | | | | | | | | | | | | | since commit 2279f540ea7d ("sched/deadline: Fix priority inheritance with multiple scheduling classes"), we should not keep it here. Signed-off-by: Hui Su <suhui_kernel@163.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Link: https://lore.kernel.org/r/20220107095254.GA49258@localhost.localdomain
* | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2022-01-201-2/+7
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge more updates from Andrew Morton: "55 patches. Subsystems affected by this patch series: percpu, procfs, sysctl, misc, core-kernel, get_maintainer, lib, checkpatch, binfmt, nilfs2, hfs, fat, adfs, panic, delayacct, kconfig, kcov, and ubsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (55 commits) lib: remove redundant assignment to variable ret ubsan: remove CONFIG_UBSAN_OBJECT_SIZE kcov: fix generic Kconfig dependencies if ARCH_WANTS_NO_INSTR lib/Kconfig.debug: make TEST_KMOD depend on PAGE_SIZE_LESS_THAN_256KB btrfs: use generic Kconfig option for 256kB page size limit arch/Kconfig: split PAGE_SIZE_LESS_THAN_256KB from PAGE_SIZE_LESS_THAN_64KB configs: introduce debug.config for CI-like setup delayacct: track delays from memory compact Documentation/accounting/delay-accounting.rst: add thrashing page cache and direct compact delayacct: cleanup flags in struct task_delay_info and functions use it delayacct: fix incomplete disable operation when switch enable to disable delayacct: support swapin delay accounting for swapping without blkio panic: remove oops_id panic: use error_report_end tracepoint on warnings fs/adfs: remove unneeded variable make code cleaner FAT: use io_schedule_timeout() instead of congestion_wait() hfsplus: use struct_group_attr() for memcpy() region nilfs2: remove redundant pointer sbufs fs/binfmt_elf: use PT_LOAD p_align values for static PIE const_structs.checkpatch: add frequently used ops structs ...
| * | tools/testing/selftests/bpf: replace open-coded 16 with TASK_COMM_LENYafang Shao2022-01-201-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the sched:sched_switch tracepoint args are derived from the kernel, we'd better make it same with the kernel. So the macro TASK_COMM_LEN is converted to type enum, then all the BPF programs can get it through BTF. The BPF program which wants to use TASK_COMM_LEN should include the header vmlinux.h. Regarding the test_stacktrace_map and test_tracepoint, as the type defined in linux/bpf.h are also defined in vmlinux.h, so we don't need to include linux/bpf.h again. Link: https://lkml.kernel.org/r/20211120112738.45980-8-laoar.shao@gmail.com Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'signal-for-v5.17' of ↵Linus Torvalds2022-01-171-2/+2
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
| * | kthread: Generalize pf_io_worker so it can point to struct kthreadEric W. Biederman2022-01-081-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The point of using set_child_tid to hold the kthread pointer was that it already did what is necessary. There are now restrictions on when set_child_tid can be initialized and when set_child_tid can be used in schedule_tail. Which indicates that continuing to use set_child_tid to hold the kthread pointer is a bad idea. Instead of continuing to use the set_child_tid field of task_struct generalize the pf_io_worker field of task_struct and use it to hold the kthread pointer. Rename pf_io_worker (which is a void * pointer) to worker_private so it can be used to store kthreads struct kthread pointer. Update the kthread code to store the kthread pointer in the worker_private field. Remove the places where set_child_tid had to be dealt with carefully because kthreads also used it. Link: https://lkml.kernel.org/r/CAHk-=wgtFAA9SbVYg0gR1tqPMC17-NYcs0GQkaYg1bGhh1uJQQ@mail.gmail.com Link: https://lkml.kernel.org/r/87a6grvqy8.fsf_-_@email.froward.int.ebiederm.org Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | Merge tag 'locking_core_for_v5.17_rc1' of ↵Linus Torvalds2022-01-111-0/+9
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Borislav Petkov: "Lots of cleanups and preparation. Highlights: - futex: Cleanup and remove runtime futex_cmpxchg detection - rtmutex: Some fixes for the PREEMPT_RT locking infrastructure - kcsan: Share owner_on_cpu() between mutex,rtmutex and rwsem and annotate the racy owner->on_cpu access *once*. - atomic64: Dead-Code-Elemination" [ Description above by Peter Zijlstra ] * tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/atomic: atomic64: Remove unusable atomic ops futex: Fix additional regressions locking: Allow to include asm/spinlock_types.h from linux/spinlock_types_raw.h x86/mm: Include spinlock_t definition in pgtable. locking: Mark racy reads of owner->on_cpu locking: Make owner_on_cpu() into <linux/sched.h> lockdep/selftests: Adapt ww-tests for PREEMPT_RT lockdep/selftests: Skip the softirq related tests on PREEMPT_RT lockdep/selftests: Unbalanced migrate_disable() & rcu_read_lock(). lockdep/selftests: Avoid using local_lock_{acquire|release}(). lockdep: Remove softirq accounting on PREEMPT_RT. locking/rtmutex: Add rt_mutex_lock_nest_lock() and rt_mutex_lock_killable(). locking/rtmutex: Squash self-deadlock check for ww_rt_mutex. locking: Remove rt_rwlock_is_contended(). sched: Trigger warning if ->migration_disabled counter underflows. futex: Fix sparc32/m68k/nds32 build regression futex: Remove futex_cmpxchg detection futex: Ensure futex_atomic_cmpxchg_inatomic() is present kernel/locking: Use a pointer in ww_mutex_trylock().
| * | locking: Mark racy reads of owner->on_cpuMarco Elver2021-12-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the more frequent data races reported by KCSAN is the racy read in mutex_spin_on_owner(), which is usually reported as "race of unknown origin" without showing the writer. This is due to the racing write occurring in kernel/sched. Locally enabling KCSAN in kernel/sched shows: | write (marked) to 0xffff97f205079934 of 4 bytes by task 316 on cpu 6: | finish_task kernel/sched/core.c:4632 [inline] | finish_task_switch kernel/sched/core.c:4848 | context_switch kernel/sched/core.c:4975 [inline] | __schedule kernel/sched/core.c:6253 | schedule kernel/sched/core.c:6326 | schedule_preempt_disabled kernel/sched/core.c:6385 | __mutex_lock_common kernel/locking/mutex.c:680 | __mutex_lock kernel/locking/mutex.c:740 [inline] | __mutex_lock_slowpath kernel/locking/mutex.c:1028 | mutex_lock kernel/locking/mutex.c:283 | tty_open_by_driver drivers/tty/tty_io.c:2062 [inline] | ... | | read to 0xffff97f205079934 of 4 bytes by task 322 on cpu 3: | mutex_spin_on_owner kernel/locking/mutex.c:370 | mutex_optimistic_spin kernel/locking/mutex.c:480 | __mutex_lock_common kernel/locking/mutex.c:610 | __mutex_lock kernel/locking/mutex.c:740 [inline] | __mutex_lock_slowpath kernel/locking/mutex.c:1028 | mutex_lock kernel/locking/mutex.c:283 | tty_open_by_driver drivers/tty/tty_io.c:2062 [inline] | ... | | value changed: 0x00000001 -> 0x00000000 This race is clearly intentional, and the potential for miscompilation is slim due to surrounding barrier() and cpu_relax(), and the value being used as a boolean. Nevertheless, marking this reader would more clearly denote intent and make it obvious that concurrency is expected. Use READ_ONCE() to avoid having to reason about compiler optimizations now and in future. With previous refactor, mark the read to owner->on_cpu in owner_on_cpu(), which immediately precedes the loop executing mutex_spin_on_owner(). Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20211203075935.136808-3-wangkefeng.wang@huawei.com
| * | locking: Make owner_on_cpu() into <linux/sched.h>Kefeng Wang2021-12-041-0/+9
| |/ | | | | | | | | | | | | | | | | | | Move the owner_on_cpu() from kernel/locking/rwsem.c into include/linux/sched.h with under CONFIG_SMP, then use it in the mutex/rwsem/rtmutex to simplify the code. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20211203075935.136808-2-wangkefeng.wang@huawei.com
* | Merge tag 'sched_core_for_v5.17_rc1' of ↵Linus Torvalds2022-01-111-0/+4
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Borislav Petkov: "Mostly minor things this time; some highlights: - core-sched: Add 'Forced Idle' accounting; this allows to track how much CPU time is 'lost' due to core scheduling constraints. - psi: Fix for MEM_FULL; a task running reclaim would be counted as a runnable task and prevent MEM_FULL from being reported. - cpuacct: Long standing fixes for some cgroup accounting issues. - rt: Bandwidth timer could, under unusual circumstances, be failed to armed, leading to indefinite throttling." [ Description above by Peter Zijlstra ] * tag 'sched_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: Replace CFS internal cpu_util() with cpu_util_cfs() sched/fair: Cleanup task_util and capacity type sched/rt: Try to restart rt period timer when rt runtime exceeded sched/fair: Document the slow path and fast path in select_task_rq_fair sched/fair: Fix per-CPU kthread and wakee stacking for asym CPU capacity sched/fair: Fix detection of per-CPU kthreads waking a task sched/cpuacct: Make user/system times in cpuacct.stat more precise sched/cpuacct: Fix user/system in shown cpuacct.usage* cpuacct: Convert BUG_ON() to WARN_ON_ONCE() cputime, cpuacct: Include guest time in user time in cpuacct.stat psi: Fix PSI_MEM_FULL state when tasks are in memstall and doing reclaim sched/core: Forced idle accounting psi: Add a missing SPDX license header psi: Remove repeated verbose comment
| * | sched/core: Forced idle accountingJosh Don2021-11-171-0/+4
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds accounting for "forced idle" time, which is time where a cookie'd task forces its SMT sibling to idle, despite the presence of runnable tasks. Forced idle time is one means to measure the cost of enabling core scheduling (ie. the capacity lost due to the need to force idle). Forced idle time is attributed to the thread responsible for causing the forced idle. A few details: - Forced idle time is displayed via /proc/PID/sched. It also requires that schedstats is enabled. - Forced idle is only accounted when a sibling hyperthread is held idle despite the presence of runnable tasks. No time is charged if a sibling is idle but has no runnable tasks. - Tasks with 0 cookie are never charged forced idle. - For SMT > 2, we scale the amount of forced idle charged based on the number of forced idle siblings. Additionally, we split the time up and evenly charge it to all running tasks, as each is equally responsible for the forced idle. Signed-off-by: Josh Don <joshdon@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20211018203428.2025792-1-joshdon@google.com
* / kcsan: Add core support for a subset of weak memory modelingMarco Elver2021-12-091-0/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for modeling a subset of weak memory, which will enable detection of a subset of data races due to missing memory barriers. KCSAN's approach to detecting missing memory barriers is based on modeling access reordering, and enabled if `CONFIG_KCSAN_WEAK_MEMORY=y`, which depends on `CONFIG_KCSAN_STRICT=y`. The feature can be enabled or disabled at boot and runtime via the `kcsan.weak_memory` boot parameter. Each memory access for which a watchpoint is set up, is also selected for simulated reordering within the scope of its function (at most 1 in-flight access). We are limited to modeling the effects of "buffering" (delaying the access), since the runtime cannot "prefetch" accesses (therefore no acquire modeling). Once an access has been selected for reordering, it is checked along every other access until the end of the function scope. If an appropriate memory barrier is encountered, the access will no longer be considered for reordering. When the result of a memory operation should be ordered by a barrier, KCSAN can then detect data races where the conflict only occurs as a result of a missing barrier due to reordering accesses. Suggested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
* Merge branch 'per_signal_struct_coredumps-for-v5.16' of ↵Linus Torvalds2021-11-031-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull per signal_struct coredumps from Eric Biederman: "Current coredumps are mixed up with the exit code, the signal handling code, and the ptrace code making coredumps much more complicated than necessary and difficult to follow. This series of changes starts with ptrace_stop and cleans it up, making it easier to follow what is happening in ptrace_stop. Then cleans up the exec interactions with coredumps. Then cleans up the coredump interactions with exit. Finally the coredump interactions with the signal handling code is cleaned up. The first and last changes are bug fixes for minor bugs. I believe the fact that vfork followed by execve can kill the process the called vfork if exec fails is sufficient justification to change the userspace visible behavior. In previous discussions some of these changes were organized differently and individually appeared to make the code base worse. As currently written I believe they all stand on their own as cleanups and bug fixes. Which means that even if the worst should happen and the last change needs to be reverted for some unimaginable reason, the code base will still be improved. If the worst does not happen there are a more cleanups that can be made. Signals that generate coredumps can easily become eligible for short circuit delivery in complete_signal. The entire rendezvous for generating a coredump can move into get_signal. The function force_sig_info_to_task be written in a way that does not modify the signal handling state of the target task (because coredumps are eligible for short circuit delivery). Many of these future cleanups can be done another way but nothing so cleanly as if coredumps become per signal_struct" * 'per_signal_struct_coredumps-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: coredump: Limit coredumps to a single thread group coredump: Don't perform any cleanups before dumping core exit: Factor coredump_exit_mm out of exit_mm exec: Check for a pending fatal signal instead of core_state ptrace: Remove the unnecessary arguments from arch_ptrace_stop signal: Remove the bogus sigkill_pending in ptrace_stop
| * coredump: Don't perform any cleanups before dumping coreEric W. Biederman2021-10-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename coredump_exit_mm to coredump_task_exit and call it from do_exit before PTRACE_EVENT_EXIT, and before any cleanup work for a task happens. This ensures that an accurate copy of the process can be captured in the coredump as no cleanup for the process happens before the coredump completes. This also ensures that PTRACE_EVENT_EXIT will not be visited by any thread until the coredump is complete. Add a new flag PF_POSTCOREDUMP so that tasks that have passed through coredump_task_exit can be recognized and ignored in zap_process. Now that all of the coredumping happens before exit_mm remove code to test for a coredump in progress from mm_release. Replace "may_ptrace_stop()" with a simple test of "current->ptrace". The other tests in may_ptrace_stop all concern avoiding stopping during a coredump. These tests are no longer necessary as it is now guaranteed that fatal_signal_pending will be set if the code enters ptrace_stop during a coredump. The code in ptrace_stop is guaranteed not to stop if fatal_signal_pending returns true. Until this change "ptrace_event(PTRACE_EVENT_EXIT)" could call ptrace_stop without fatal_signal_pending being true, as signals are dequeued in get_signal before calling do_exit. This is no longer an issue as "ptrace_event(PTRACE_EVENT_EXIT)" is no longer reached until after the coredump completes. Link: https://lkml.kernel.org/r/874kaax26c.fsf@disp2133 Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | Merge tag 'cpu-to-thread_info-v5.16-rc1' of ↵Linus Torvalds2021-11-011-12/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull thread_info update to move 'cpu' back from task_struct from Kees Cook: "Cross-architecture update to move task_struct::cpu back into thread_info on arm64, x86, s390, powerpc, and riscv. All Acked by arch maintainers. Quoting Ard Biesheuvel: 'Move task_struct::cpu back into thread_info Keeping CPU in task_struct is problematic for architectures that define raw_smp_processor_id() in terms of this field, as it requires linux/sched.h to be included, which causes a lot of pain in terms of circular dependencies (aka 'header soup') This series moves it back into thread_info (where it came from) for all architectures that enable THREAD_INFO_IN_TASK, addressing the header soup issue as well as some pointless differences in the implementations of task_cpu() and set_task_cpu()'" * tag 'cpu-to-thread_info-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: riscv: rely on core code to keep thread_info::cpu updated powerpc: smp: remove hack to obtain offset of task_struct::cpu sched: move CPU field back into thread_info if THREAD_INFO_IN_TASK=y powerpc: add CPU field to struct thread_info s390: add CPU field to struct thread_info x86: add CPU field to struct thread_info arm64: add CPU field to struct thread_info
| * | sched: move CPU field back into thread_info if THREAD_INFO_IN_TASK=yArd Biesheuvel2021-09-301-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | THREAD_INFO_IN_TASK moved the CPU field out of thread_info, but this causes some issues on architectures that define raw_smp_processor_id() in terms of this field, due to the fact that #include'ing linux/sched.h to get at struct task_struct is problematic in terms of circular dependencies. Given that thread_info and task_struct are the same data structure anyway when THREAD_INFO_IN_TASK=y, let's move it back so that having access to the type definition of struct thread_info is sufficient to reference the CPU number of the current task. Note that this requires THREAD_INFO_IN_TASK's definition of the task_thread_info() helper to be updated, as task_cpu() takes a pointer-to-const, whereas task_thread_info() (which is used to generate lvalues as well), needs a non-const pointer. So make it a macro instead. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
* | | Merge tag 'sched-core-2021-11-01' of ↵Linus Torvalds2021-11-011-4/+7
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Thomas Gleixner: - Revert the printk format based wchan() symbol resolution as it can leak the raw value in case that the symbol is not resolvable. - Make wchan() more robust and work with all kind of unwinders by enforcing that the task stays blocked while unwinding is in progress. - Prevent sched_fork() from accessing an invalid sched_task_group - Improve asymmetric packing logic - Extend scheduler statistics to RT and DL scheduling classes and add statistics for bandwith burst to the SCHED_FAIR class. - Properly account SCHED_IDLE entities - Prevent a potential deadlock when initial priority is assigned to a newly created kthread. A recent change to plug a race between cpuset and __sched_setscheduler() introduced a new lock dependency which is now triggered. Break the lock dependency chain by moving the priority assignment to the thread function. - Fix the idle time reporting in /proc/uptime for NOHZ enabled systems. - Improve idle balancing in general and especially for NOHZ enabled systems. - Provide proper interfaces for live patching so it does not have to fiddle with scheduler internals. - Add cluster aware scheduling support. - A small set of tweaks for RT (irqwork, wait_task_inactive(), various scheduler options and delaying mmdrop) - The usual small tweaks and improvements all over the place * tag 'sched-core-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits) sched/fair: Cleanup newidle_balance sched/fair: Remove sysctl_sched_migration_cost condition sched/fair: Wait before decaying max_newidle_lb_cost sched/fair: Skip update_blocked_averages if we are defering load balance sched/fair: Account update_blocked_averages in newidle_balance cost x86: Fix __get_wchan() for !STACKTRACE sched,x86: Fix L2 cache mask sched/core: Remove rq_relock() sched: Improve wake_up_all_idle_cpus() take #2 irq_work: Also rcuwait for !IRQ_WORK_HARD_IRQ on PREEMPT_RT irq_work: Handle some irq_work in a per-CPU thread on PREEMPT_RT irq_work: Allow irq_work_sync() to sleep if irq_work() no IRQ support. sched/rt: Annotate the RT balancing logic irqwork as IRQ_WORK_HARD_IRQ sched: Add cluster scheduler level for x86 sched: Add cluster scheduler level in core and related Kconfig for ARM64 topology: Represent clusters of CPUs within a die sched: Disable -Wunused-but-set-variable sched: Add wrapper for get_wchan() to keep task blocked x86: Fix get_wchan() to support the ORC unwinder proc: Use task_is_running() for wchan in /proc/$pid/stat ...
| * | | sched: Add wrapper for get_wchan() to keep task blockedKees Cook2021-10-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having a stable wchan means the process must be blocked and for it to stay that way while performing stack unwinding. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm] Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64] Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org
| * | | sched: Fill unconditional hole induced by sched_entityKees Cook2021-10-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With struct sched_entity before the other sched entities, its alignment won't induce a struct hole. This saves 64 bytes in defconfig task_struct: Before: ... unsigned int rt_priority; /* 120 4 */ /* XXX 4 bytes hole, try to pack */ /* --- cacheline 2 boundary (128 bytes) --- */ const struct sched_class * sched_class; /* 128 8 */ /* XXX 56 bytes hole, try to pack */ /* --- cacheline 3 boundary (192 bytes) --- */ struct sched_entity se __attribute__((__aligned__(64))); /* 192 448 */ /* --- cacheline 10 boundary (640 bytes) --- */ struct sched_rt_entity rt; /* 640 48 */ struct sched_dl_entity dl __attribute__((__aligned__(8))); /* 688 224 */ /* --- cacheline 14 boundary (896 bytes) was 16 bytes ago --- */ After: ... unsigned int rt_priority; /* 120 4 */ /* XXX 4 bytes hole, try to pack */ /* --- cacheline 2 boundary (128 bytes) --- */ struct sched_entity se __attribute__((__aligned__(64))); /* 128 448 */ /* --- cacheline 9 boundary (576 bytes) --- */ struct sched_rt_entity rt; /* 576 48 */ struct sched_dl_entity dl __attribute__((__aligned__(8))); /* 624 224 */ /* --- cacheline 13 boundary (832 bytes) was 16 bytes ago --- */ Summary diff: - /* size: 7040, cachelines: 110, members: 188 */ + /* size: 6976, cachelines: 109, members: 188 */ Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210924025450.4138503-1-keescook@chromium.org
| * | | sched: Introduce task block time in schedstatsYafang Shao2021-10-051-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently in schedstats we have sum_sleep_runtime and iowait_sum, but there's no metric to show how long the task is in D state. Once a task in D state, it means the task is blocked in the kernel, for example the task may be waiting for a mutex. The D state is more frequent than iowait, and it is more critital than S state. So it is worth to add a metric to measure it. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20210905143547.4668-5-laoar.shao@gmail.com
| * | | sched: Make struct sched_statistics independent of fair sched classYafang Shao2021-10-051-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we want to use the schedstats facility to trace other sched classes, we should make it independent of fair sched class. The struct sched_statistics is the schedular statistics of a task_struct or a task_group. So we can move it into struct task_struct and struct task_group to achieve the goal. After the patch, schestats are orgnized as follows, struct task_struct { ... struct sched_entity se; struct sched_rt_entity rt; struct sched_dl_entity dl; ... struct sched_statistics stats; ... }; Regarding the task group, schedstats is only supported for fair group sched, and a new struct sched_entity_stats is introduced, suggested by Peter - struct sched_entity_stats { struct sched_entity se; struct sched_statistics stats; } __no_randomize_layout; Then with the se in a task_group, we can easily get the stats. The sched_statistics members may be frequently modified when schedstats is enabled, in order to avoid impacting on random data which may in the same cacheline with them, the struct sched_statistics is defined as cacheline aligned. As this patch changes the core struct of scheduler, so I verified the performance it may impact on the scheduler with 'perf bench sched pipe', suggested by Mel. Below is the result, in which all the values are in usecs/op. Before After kernel.sched_schedstats=0 5.2~5.4 5.2~5.4 kernel.sched_schedstats=1 5.3~5.5 5.3~5.5 [These data is a little difference with the earlier version, that is because my old test machine is destroyed so I have to use a new different test machine.] Almost no impact on the sched performance. No functional change. [lkp@intel.com: reported build failure in earlier version] Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lore.kernel.org/r/20210905143547.4668-3-laoar.shao@gmail.com
* | | | Merge tag 'locking-core-2021-10-31' of ↵Linus Torvalds2021-11-011-10/+29
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Thomas Gleixner: - Move futex code into kernel/futex/ and split up the kitchen sink into seperate files to make integration of sys_futex_waitv() simpler. - Add a new sys_futex_waitv() syscall which allows to wait on multiple futexes. The main use case is emulating Windows' WaitForMultipleObjects which allows Wine to improve the performance of Windows Games. Also native Linux games can benefit from this interface as this is a common wait pattern for this kind of applications. - Add context to ww_mutex_trylock() to provide a path for i915 to rework their eviction code step by step without making lockdep upset until the final steps of rework are completed. It's also useful for regulator and TTM to avoid dropping locks in the non contended path. - Lockdep and might_sleep() cleanups and improvements - A few improvements for the RT substitutions. - The usual small improvements and cleanups. * tag 'locking-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) locking: Remove spin_lock_flags() etc locking/rwsem: Fix comments about reader optimistic lock stealing conditions locking: Remove rcu_read_{,un}lock() for preempt_{dis,en}able() locking/rwsem: Disable preemption for spinning region docs: futex: Fix kernel-doc references futex: Fix PREEMPT_RT build futex2: Documentation: Document sys_futex_waitv() uAPI selftests: futex: Test sys_futex_waitv() wouldblock selftests: futex: Test sys_futex_waitv() timeout selftests: futex: Add sys_futex_waitv() test futex,arm: Wire up sys_futex_waitv() futex,x86: Wire up sys_futex_waitv() futex: Implement sys_futex_waitv() futex: Simplify double_lock_hb() futex: Split out wait/wake futex: Split out requeue futex: Rename mark_wake_futex() futex: Rename: match_futex() futex: Rename: hb_waiter_{inc,dec,pending}() futex: Split out PI futex ...
| * | | | sched: Make cond_resched_lock() variants RT awareThomas Gleixner2021-10-011-9/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __might_resched() checks in the cond_resched_lock() variants use PREEMPT_LOCK_OFFSET for preempt count offset checking which takes the preemption disable by the spin_lock() which is still held at that point into account. On PREEMPT_RT enabled kernels spin/rw_lock held sections stay preemptible which means PREEMPT_LOCK_OFFSET is 0, but that still triggers the __might_resched() check because that takes RCU read side nesting into account. On RT enabled kernels spin/read/write_lock() issue rcu_read_lock() to resemble the !RT semantics, which means in cond_resched_lock() the might resched check will see preempt_count() == 0 and rcu_preempt_depth() == 1. Introduce PREEMPT_LOCK_SCHED_OFFSET for those might resched checks and map them depending on CONFIG_PREEMPT_RT. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210923165358.305969211@linutronix.de
| * | | | sched: Make RCU nest depth distinct in __might_resched()Thomas Gleixner2021-10-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For !RT kernels RCU nest depth in __might_resched() is always expected to be 0, but on RT kernels it can be non zero while the preempt count is expected to be always 0. Instead of playing magic games in interpreting the 'preempt_offset' argument, rename it to 'offsets' and use the lower 8 bits for the expected preempt count, allow to hand in the expected RCU nest depth in the upper bits and adopt the __might_resched() code and related checks and printks. The affected call sites are updated in subsequent steps. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210923165358.243232823@linutronix.de
| * | | | sched: Make cond_resched_*lock() variants consistent vs. might_sleep()Thomas Gleixner2021-10-011-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 3427445afd26 ("sched: Exclude cond_resched() from nested sleep test") removed the task state check of __might_sleep() for cond_resched_lock() because cond_resched_lock() is not a voluntary scheduling point which blocks. It's a preemption point which requires the lock holder to release the spin lock. The same rationale applies to cond_resched_rwlock_read/write(), but those were not touched. Make it consistent and use the non-state checking __might_resched() there as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210923165357.991262778@linutronix.de
| * | | | sched: Clean up the might_sleep() underscore zooThomas Gleixner2021-10-011-4/+4
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __might_sleep() vs. ___might_sleep() is hard to distinguish. Aside of that the three underscore variant is exposed to provide a checkpoint for rescheduling points which are distinct from blocking points. They are semantically a preemption point which means that scheduling is state preserving. A real blocking operation, e.g. mutex_lock(), wait*(), which cannot preserve a task state which is not equal to RUNNING. While technically blocking on a "sleeping" spinlock in RT enabled kernels falls into the voluntary scheduling category because it has to wait until the contended spin/rw lock becomes available, the RT lock substitution code can semantically be mapped to a voluntary preemption because the RT lock substitution code and the scheduler are providing mechanisms to preserve the task state and to take regular non-lock related wakeups into account. Rename ___might_sleep() to __might_resched() to make the distinction of these functions clear. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210923165357.928693482@linutronix.de
* | | | sched: make task_struct->plug always definedJens Axboe2021-10-221-2/+0
| |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_BLOCK isn't set, then it's an empty struct anyway. Just make it generally available, so we don't break the compile: kernel/sched/core.c: In function ‘sched_submit_work’: kernel/sched/core.c:6346:35: error: ‘struct task_struct’ has no member named ‘plug’ 6346 | blk_flush_plug(tsk->plug, true); | ^~ kernel/sched/core.c: In function ‘io_schedule_prepare’: kernel/sched/core.c:8357:20: error: ‘struct task_struct’ has no member named ‘plug’ 8357 | if (current->plug) | ^~ kernel/sched/core.c:8358:39: error: ‘struct task_struct’ has no member named ‘plug’ 8358 | blk_flush_plug(current->plug, true); | ^~ Reported-by: Nathan Chancellor <nathan@kernel.org> Fixes: 008f75a20e70 ("block: cleanup the flush plug helpers") Signed-off-by: Jens Axboe <axboe@kernel.dk>