diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /kernel/freezer.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'kernel/freezer.c')
-rw-r--r-- | kernel/freezer.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/kernel/freezer.c b/kernel/freezer.c new file mode 100644 index 000000000..4fad0e6fc --- /dev/null +++ b/kernel/freezer.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * kernel/freezer.c - Function to freeze a process + * + * Originally from kernel/power/process.c + */ + +#include <linux/interrupt.h> +#include <linux/suspend.h> +#include <linux/export.h> +#include <linux/syscalls.h> +#include <linux/freezer.h> +#include <linux/kthread.h> + +/* total number of freezing conditions in effect */ +DEFINE_STATIC_KEY_FALSE(freezer_active); +EXPORT_SYMBOL(freezer_active); + +/* + * indicate whether PM freezing is in effect, protected by + * system_transition_mutex + */ +bool pm_freezing; +bool pm_nosig_freezing; + +/* protects freezing and frozen transitions */ +static DEFINE_SPINLOCK(freezer_lock); + +/** + * freezing_slow_path - slow path for testing whether a task needs to be frozen + * @p: task to be tested + * + * This function is called by freezing() if freezer_active isn't zero + * and tests whether @p needs to enter and stay in frozen state. Can be + * called under any context. The freezers are responsible for ensuring the + * target tasks see the updated state. + */ +bool freezing_slow_path(struct task_struct *p) +{ + if (p->flags & (PF_NOFREEZE | PF_SUSPEND_TASK)) + return false; + + if (test_tsk_thread_flag(p, TIF_MEMDIE)) + return false; + + if (pm_nosig_freezing || cgroup_freezing(p)) + return true; + + if (pm_freezing && !(p->flags & PF_KTHREAD)) + return true; + + return false; +} +EXPORT_SYMBOL(freezing_slow_path); + +bool frozen(struct task_struct *p) +{ + return READ_ONCE(p->__state) & TASK_FROZEN; +} + +/* Refrigerator is place where frozen processes are stored :-). */ +bool __refrigerator(bool check_kthr_stop) +{ + unsigned int state = get_current_state(); + bool was_frozen = false; + + pr_debug("%s entered refrigerator\n", current->comm); + + WARN_ON_ONCE(state && !(state & TASK_NORMAL)); + + for (;;) { + bool freeze; + + set_current_state(TASK_FROZEN); + + spin_lock_irq(&freezer_lock); + freeze = freezing(current) && !(check_kthr_stop && kthread_should_stop()); + spin_unlock_irq(&freezer_lock); + + if (!freeze) + break; + + was_frozen = true; + schedule(); + } + __set_current_state(TASK_RUNNING); + + pr_debug("%s left refrigerator\n", current->comm); + + return was_frozen; +} +EXPORT_SYMBOL(__refrigerator); + +static void fake_signal_wake_up(struct task_struct *p) +{ + unsigned long flags; + + if (lock_task_sighand(p, &flags)) { + signal_wake_up(p, 0); + unlock_task_sighand(p, &flags); + } +} + +static int __set_task_frozen(struct task_struct *p, void *arg) +{ + unsigned int state = READ_ONCE(p->__state); + + if (p->on_rq) + return 0; + + if (p != current && task_curr(p)) + return 0; + + if (!(state & (TASK_FREEZABLE | __TASK_STOPPED | __TASK_TRACED))) + return 0; + + /* + * Only TASK_NORMAL can be augmented with TASK_FREEZABLE, since they + * can suffer spurious wakeups. + */ + if (state & TASK_FREEZABLE) + WARN_ON_ONCE(!(state & TASK_NORMAL)); + +#ifdef CONFIG_LOCKDEP + /* + * It's dangerous to freeze with locks held; there be dragons there. + */ + if (!(state & __TASK_FREEZABLE_UNSAFE)) + WARN_ON_ONCE(debug_locks && p->lockdep_depth); +#endif + + WRITE_ONCE(p->__state, TASK_FROZEN); + return TASK_FROZEN; +} + +static bool __freeze_task(struct task_struct *p) +{ + /* TASK_FREEZABLE|TASK_STOPPED|TASK_TRACED -> TASK_FROZEN */ + return task_call_func(p, __set_task_frozen, NULL); +} + +/** + * freeze_task - send a freeze request to given task + * @p: task to send the request to + * + * If @p is freezing, the freeze request is sent either by sending a fake + * signal (if it's not a kernel thread) or waking it up (if it's a kernel + * thread). + * + * RETURNS: + * %false, if @p is not freezing or already frozen; %true, otherwise + */ +bool freeze_task(struct task_struct *p) +{ + unsigned long flags; + + spin_lock_irqsave(&freezer_lock, flags); + if (!freezing(p) || frozen(p) || __freeze_task(p)) { + spin_unlock_irqrestore(&freezer_lock, flags); + return false; + } + + if (!(p->flags & PF_KTHREAD)) + fake_signal_wake_up(p); + else + wake_up_state(p, TASK_NORMAL); + + spin_unlock_irqrestore(&freezer_lock, flags); + return true; +} + +/* + * The special task states (TASK_STOPPED, TASK_TRACED) keep their canonical + * state in p->jobctl. If either of them got a wakeup that was missed because + * TASK_FROZEN, then their canonical state reflects that and the below will + * refuse to restore the special state and instead issue the wakeup. + */ +static int __set_task_special(struct task_struct *p, void *arg) +{ + unsigned int state = 0; + + if (p->jobctl & JOBCTL_TRACED) + state = TASK_TRACED; + + else if (p->jobctl & JOBCTL_STOPPED) + state = TASK_STOPPED; + + if (state) + WRITE_ONCE(p->__state, state); + + return state; +} + +void __thaw_task(struct task_struct *p) +{ + unsigned long flags, flags2; + + spin_lock_irqsave(&freezer_lock, flags); + if (WARN_ON_ONCE(freezing(p))) + goto unlock; + + if (lock_task_sighand(p, &flags2)) { + /* TASK_FROZEN -> TASK_{STOPPED,TRACED} */ + bool ret = task_call_func(p, __set_task_special, NULL); + unlock_task_sighand(p, &flags2); + if (ret) + goto unlock; + } + + wake_up_state(p, TASK_FROZEN); +unlock: + spin_unlock_irqrestore(&freezer_lock, flags); +} + +/** + * set_freezable - make %current freezable + * + * Mark %current freezable and enter refrigerator if necessary. + */ +bool set_freezable(void) +{ + might_sleep(); + + /* + * Modify flags while holding freezer_lock. This ensures the + * freezer notices that we aren't frozen yet or the freezing + * condition is visible to try_to_freeze() below. + */ + spin_lock_irq(&freezer_lock); + current->flags &= ~PF_NOFREEZE; + spin_unlock_irq(&freezer_lock); + + return try_to_freeze(); +} +EXPORT_SYMBOL(set_freezable); |