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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /rust/kernel/print.rs
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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 'rust/kernel/print.rs')
-rw-r--r--rust/kernel/print.rs413
1 files changed, 413 insertions, 0 deletions
diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs
new file mode 100644
index 000000000..301033256
--- /dev/null
+++ b/rust/kernel/print.rs
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Printing facilities.
+//!
+//! C header: [`include/linux/printk.h`](../../../../include/linux/printk.h)
+//!
+//! Reference: <https://www.kernel.org/doc/html/latest/core-api/printk-basics.html>
+
+use core::{
+ ffi::{c_char, c_void},
+ fmt,
+};
+
+use crate::str::RawFormatter;
+
+#[cfg(CONFIG_PRINTK)]
+use crate::bindings;
+
+// Called from `vsprintf` with format specifier `%pA`.
+#[no_mangle]
+unsafe fn rust_fmt_argument(buf: *mut c_char, end: *mut c_char, ptr: *const c_void) -> *mut c_char {
+ use fmt::Write;
+ // SAFETY: The C contract guarantees that `buf` is valid if it's less than `end`.
+ let mut w = unsafe { RawFormatter::from_ptrs(buf.cast(), end.cast()) };
+ let _ = w.write_fmt(unsafe { *(ptr as *const fmt::Arguments<'_>) });
+ w.pos().cast()
+}
+
+/// Format strings.
+///
+/// Public but hidden since it should only be used from public macros.
+#[doc(hidden)]
+pub mod format_strings {
+ use crate::bindings;
+
+ /// The length we copy from the `KERN_*` kernel prefixes.
+ const LENGTH_PREFIX: usize = 2;
+
+ /// The length of the fixed format strings.
+ pub const LENGTH: usize = 10;
+
+ /// Generates a fixed format string for the kernel's [`_printk`].
+ ///
+ /// The format string is always the same for a given level, i.e. for a
+ /// given `prefix`, which are the kernel's `KERN_*` constants.
+ ///
+ /// [`_printk`]: ../../../../include/linux/printk.h
+ const fn generate(is_cont: bool, prefix: &[u8; 3]) -> [u8; LENGTH] {
+ // Ensure the `KERN_*` macros are what we expect.
+ assert!(prefix[0] == b'\x01');
+ if is_cont {
+ assert!(prefix[1] == b'c');
+ } else {
+ assert!(prefix[1] >= b'0' && prefix[1] <= b'7');
+ }
+ assert!(prefix[2] == b'\x00');
+
+ let suffix: &[u8; LENGTH - LENGTH_PREFIX] = if is_cont {
+ b"%pA\0\0\0\0\0"
+ } else {
+ b"%s: %pA\0"
+ };
+
+ [
+ prefix[0], prefix[1], suffix[0], suffix[1], suffix[2], suffix[3], suffix[4], suffix[5],
+ suffix[6], suffix[7],
+ ]
+ }
+
+ // Generate the format strings at compile-time.
+ //
+ // This avoids the compiler generating the contents on the fly in the stack.
+ //
+ // Furthermore, `static` instead of `const` is used to share the strings
+ // for all the kernel.
+ pub static EMERG: [u8; LENGTH] = generate(false, bindings::KERN_EMERG);
+ pub static ALERT: [u8; LENGTH] = generate(false, bindings::KERN_ALERT);
+ pub static CRIT: [u8; LENGTH] = generate(false, bindings::KERN_CRIT);
+ pub static ERR: [u8; LENGTH] = generate(false, bindings::KERN_ERR);
+ pub static WARNING: [u8; LENGTH] = generate(false, bindings::KERN_WARNING);
+ pub static NOTICE: [u8; LENGTH] = generate(false, bindings::KERN_NOTICE);
+ pub static INFO: [u8; LENGTH] = generate(false, bindings::KERN_INFO);
+ pub static DEBUG: [u8; LENGTH] = generate(false, bindings::KERN_DEBUG);
+ pub static CONT: [u8; LENGTH] = generate(true, bindings::KERN_CONT);
+}
+
+/// Prints a message via the kernel's [`_printk`].
+///
+/// Public but hidden since it should only be used from public macros.
+///
+/// # Safety
+///
+/// The format string must be one of the ones in [`format_strings`], and
+/// the module name must be null-terminated.
+///
+/// [`_printk`]: ../../../../include/linux/_printk.h
+#[doc(hidden)]
+#[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
+pub unsafe fn call_printk(
+ format_string: &[u8; format_strings::LENGTH],
+ module_name: &[u8],
+ args: fmt::Arguments<'_>,
+) {
+ // `_printk` does not seem to fail in any path.
+ #[cfg(CONFIG_PRINTK)]
+ unsafe {
+ bindings::_printk(
+ format_string.as_ptr() as _,
+ module_name.as_ptr(),
+ &args as *const _ as *const c_void,
+ );
+ }
+}
+
+/// Prints a message via the kernel's [`_printk`] for the `CONT` level.
+///
+/// Public but hidden since it should only be used from public macros.
+///
+/// [`_printk`]: ../../../../include/linux/printk.h
+#[doc(hidden)]
+#[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
+pub fn call_printk_cont(args: fmt::Arguments<'_>) {
+ // `_printk` does not seem to fail in any path.
+ //
+ // SAFETY: The format string is fixed.
+ #[cfg(CONFIG_PRINTK)]
+ unsafe {
+ bindings::_printk(
+ format_strings::CONT.as_ptr() as _,
+ &args as *const _ as *const c_void,
+ );
+ }
+}
+
+/// Performs formatting and forwards the string to [`call_printk`].
+///
+/// Public but hidden since it should only be used from public macros.
+#[doc(hidden)]
+#[cfg(not(testlib))]
+#[macro_export]
+#[allow(clippy::crate_in_macro_def)]
+macro_rules! print_macro (
+ // The non-continuation cases (most of them, e.g. `INFO`).
+ ($format_string:path, false, $($arg:tt)+) => (
+ // To remain sound, `arg`s must be expanded outside the `unsafe` block.
+ // Typically one would use a `let` binding for that; however, `format_args!`
+ // takes borrows on the arguments, but does not extend the scope of temporaries.
+ // Therefore, a `match` expression is used to keep them around, since
+ // the scrutinee is kept until the end of the `match`.
+ match format_args!($($arg)+) {
+ // SAFETY: This hidden macro should only be called by the documented
+ // printing macros which ensure the format string is one of the fixed
+ // ones. All `__LOG_PREFIX`s are null-terminated as they are generated
+ // by the `module!` proc macro or fixed values defined in a kernel
+ // crate.
+ args => unsafe {
+ $crate::print::call_printk(
+ &$format_string,
+ crate::__LOG_PREFIX,
+ args,
+ );
+ }
+ }
+ );
+
+ // The `CONT` case.
+ ($format_string:path, true, $($arg:tt)+) => (
+ $crate::print::call_printk_cont(
+ format_args!($($arg)+),
+ );
+ );
+);
+
+/// Stub for doctests
+#[cfg(testlib)]
+#[macro_export]
+macro_rules! print_macro (
+ ($format_string:path, $e:expr, $($arg:tt)+) => (
+ ()
+ );
+);
+
+// We could use a macro to generate these macros. However, doing so ends
+// up being a bit ugly: it requires the dollar token trick to escape `$` as
+// well as playing with the `doc` attribute. Furthermore, they cannot be easily
+// imported in the prelude due to [1]. So, for the moment, we just write them
+// manually, like in the C side; while keeping most of the logic in another
+// macro, i.e. [`print_macro`].
+//
+// [1]: https://github.com/rust-lang/rust/issues/52234
+
+/// Prints an emergency-level message (level 0).
+///
+/// Use this level if the system is unusable.
+///
+/// Equivalent to the kernel's [`pr_emerg`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_emerg`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_emerg
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_emerg!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_emerg (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::EMERG, false, $($arg)*)
+ )
+);
+
+/// Prints an alert-level message (level 1).
+///
+/// Use this level if action must be taken immediately.
+///
+/// Equivalent to the kernel's [`pr_alert`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_alert`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_alert
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_alert!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_alert (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::ALERT, false, $($arg)*)
+ )
+);
+
+/// Prints a critical-level message (level 2).
+///
+/// Use this level for critical conditions.
+///
+/// Equivalent to the kernel's [`pr_crit`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_crit`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_crit
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_crit!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_crit (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::CRIT, false, $($arg)*)
+ )
+);
+
+/// Prints an error-level message (level 3).
+///
+/// Use this level for error conditions.
+///
+/// Equivalent to the kernel's [`pr_err`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_err`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_err
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_err!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_err (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::ERR, false, $($arg)*)
+ )
+);
+
+/// Prints a warning-level message (level 4).
+///
+/// Use this level for warning conditions.
+///
+/// Equivalent to the kernel's [`pr_warn`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_warn`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_warn
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_warn!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_warn (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::WARNING, false, $($arg)*)
+ )
+);
+
+/// Prints a notice-level message (level 5).
+///
+/// Use this level for normal but significant conditions.
+///
+/// Equivalent to the kernel's [`pr_notice`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_notice`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_notice
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_notice!("hello {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_notice (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::NOTICE, false, $($arg)*)
+ )
+);
+
+/// Prints an info-level message (level 6).
+///
+/// Use this level for informational messages.
+///
+/// Equivalent to the kernel's [`pr_info`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_info`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_info
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_info!("hello {}\n", "there");
+/// ```
+#[macro_export]
+#[doc(alias = "print")]
+macro_rules! pr_info (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::INFO, false, $($arg)*)
+ )
+);
+
+/// Prints a debug-level message (level 7).
+///
+/// Use this level for debug messages.
+///
+/// Equivalent to the kernel's [`pr_debug`] macro, except that it doesn't support dynamic debug
+/// yet.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_debug`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_debug
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// pr_debug!("hello {}\n", "there");
+/// ```
+#[macro_export]
+#[doc(alias = "print")]
+macro_rules! pr_debug (
+ ($($arg:tt)*) => (
+ if cfg!(debug_assertions) {
+ $crate::print_macro!($crate::print::format_strings::DEBUG, false, $($arg)*)
+ }
+ )
+);
+
+/// Continues a previous log message in the same line.
+///
+/// Use only when continuing a previous `pr_*!` macro (e.g. [`pr_info!`]).
+///
+/// Equivalent to the kernel's [`pr_cont`] macro.
+///
+/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and
+/// `alloc::format!` for information about the formatting syntax.
+///
+/// [`pr_cont`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_cont
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::pr_cont;
+/// pr_info!("hello");
+/// pr_cont!(" {}\n", "there");
+/// ```
+#[macro_export]
+macro_rules! pr_cont (
+ ($($arg:tt)*) => (
+ $crate::print_macro!($crate::print::format_strings::CONT, true, $($arg)*)
+ )
+);