starfive-tech/linux.git/kernel/trace, branch master

Merge tag 'trace-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2021-05-06T17:03:38+00:00

Pull tracing fix from Steven Rostedt: "Fix probes written to the set_ftrace_filter file Now that there's a library that accesses the tracefs file system (libtracefs), the way the files are interacted with is slightly different than the command line. For instance, the write() system call is used directly instead of an echo. This exposes some old bugs. If a probe is written to "set_ftrace_filter" without any white space after it, it will be ignored. This is because the write expects that a string written to it that does not end with white spaces thinks there is more to come. But if the file is closed, the release function needs to finish it. The "set_ftrace_filter" release function handles the filter part of the "set_ftrace_filter" file, but did not handle the probe part" * tag 'trace-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Handle commands when closing set_ftrace_filter file

ftrace: Handle commands when closing set_ftrace_filter file

2021-05-05T14:38:24+00:00

# echo switch_mm:traceoff > /sys/kernel/tracing/set_ftrace_filter will cause switch_mm to stop tracing by the traceoff command. # echo -n switch_mm:traceoff > /sys/kernel/tracing/set_ftrace_filter does nothing. The reason is that the parsing in the write function only processes commands if it finished parsing (there is white space written after the command). That's to handle: write(fd, "switch_mm:", 10); write(fd, "traceoff", 8); cases, where the command is broken over multiple writes. The problem is if the file descriptor is closed, then the write call is not processed, and the command needs to be processed in the release code. The release code can handle matching of functions, but does not handle commands. Cc: stable@vger.kernel.org Fixes: eda1e32855656 ("tracing: handle broken names in ftrace filter") Signed-off-by: Steven Rostedt (VMware)

Merge tag 'trace-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2021-05-03T18:19:54+00:00

Pull tracing updates from Steven Rostedt: "New feature: - A new "func-no-repeats" option in tracefs/options directory. When set the function tracer will detect if the current function being traced is the same as the previous one, and instead of recording it, it will keep track of the number of times that the function is repeated in a row. And when another function is recorded, it will write a new event that shows the function that repeated, the number of times it repeated and the time stamp of when the last repeated function occurred. Enhancements: - In order to implement the above "func-no-repeats" option, the ring buffer timestamp can now give the accurate timestamp of the event as it is being recorded, instead of having to record an absolute timestamp for all events. This helps the histogram code which no longer needs to waste ring buffer space. - New validation logic to make sure all trace events that access dereferenced pointers do so in a safe way, and will warn otherwise. Fixes: - No longer limit the PIDs of tasks that are recorded for "saved_cmdlines" to PID_MAX_DEFAULT (32768), as systemd now allows for a much larger range. This caused the mapping of PIDs to the task names to be dropped for all tasks with a PID greater than 32768. - Change trace_clock_global() to never block. This caused a deadlock. Clean ups: - Typos, prototype fixes, and removing of duplicate or unused code. - Better management of ftrace_page allocations" * tag 'trace-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (32 commits) tracing: Restructure trace_clock_global() to never block tracing: Map all PIDs to command lines ftrace: Reuse the output of the function tracer for func_repeats tracing: Add "func_no_repeats" option for function tracing tracing: Unify the logic for function tracing options tracing: Add method for recording "func_repeats" events tracing: Add "last_func_repeats" to struct trace_array tracing: Define new ftrace event "func_repeats" tracing: Define static void trace_print_time() ftrace: Simplify the calculation of page number for ftrace_page->records some more ftrace: Store the order of pages allocated in ftrace_page tracing: Remove unused argument from "ring_buffer_time_stamp() tracing: Remove duplicate struct declaration in trace_events.h tracing: Update create_system_filter() kernel-doc comment tracing: A minor cleanup for create_system_filter() kernel: trace: Mundane typo fixes in the file trace_events_filter.c tracing: Fix various typos in comments scripts/recordmcount.pl: Make vim and emacs indent the same scripts/recordmcount.pl: Make indent spacing consistent tracing: Add a verifier to check string pointers for trace events ...

tracing: Restructure trace_clock_global() to never block

2021-04-30T17:48:07+00:00

It was reported that a fix to the ring buffer recursion detection would cause a hung machine when performing suspend / resume testing. The following backtrace was extracted from debugging that case: Call Trace: trace_clock_global+0x91/0xa0 __rb_reserve_next+0x237/0x460 ring_buffer_lock_reserve+0x12a/0x3f0 trace_buffer_lock_reserve+0x10/0x50 __trace_graph_return+0x1f/0x80 trace_graph_return+0xb7/0xf0 ? trace_clock_global+0x91/0xa0 ftrace_return_to_handler+0x8b/0xf0 ? pv_hash+0xa0/0xa0 return_to_handler+0x15/0x30 ? ftrace_graph_caller+0xa0/0xa0 ? trace_clock_global+0x91/0xa0 ? __rb_reserve_next+0x237/0x460 ? ring_buffer_lock_reserve+0x12a/0x3f0 ? trace_event_buffer_lock_reserve+0x3c/0x120 ? trace_event_buffer_reserve+0x6b/0xc0 ? trace_event_raw_event_device_pm_callback_start+0x125/0x2d0 ? dpm_run_callback+0x3b/0xc0 ? pm_ops_is_empty+0x50/0x50 ? platform_get_irq_byname_optional+0x90/0x90 ? trace_device_pm_callback_start+0x82/0xd0 ? dpm_run_callback+0x49/0xc0 With the following RIP: RIP: 0010:native_queued_spin_lock_slowpath+0x69/0x200 Since the fix to the recursion detection would allow a single recursion to happen while tracing, this lead to the trace_clock_global() taking a spin lock and then trying to take it again: ring_buffer_lock_reserve() { trace_clock_global() { arch_spin_lock() { queued_spin_lock_slowpath() { /* lock taken */ (something else gets traced by function graph tracer) ring_buffer_lock_reserve() { trace_clock_global() { arch_spin_lock() { queued_spin_lock_slowpath() { /* DEAD LOCK! */ Tracing should *never* block, as it can lead to strange lockups like the above. Restructure the trace_clock_global() code to instead of simply taking a lock to update the recorded "prev_time" simply use it, as two events happening on two different CPUs that calls this at the same time, really doesn't matter which one goes first. Use a trylock to grab the lock for updating the prev_time, and if it fails, simply try again the next time. If it failed to be taken, that means something else is already updating it. Link: https://lkml.kernel.org/r/20210430121758.650b6e8a@gandalf.local.home Cc: stable@vger.kernel.org Tested-by: Konstantin Kharlamov Tested-by: Todd Brandt Fixes: b02414c8f045 ("ring-buffer: Fix recursion protection transitions between interrupt context") # started showing the problem Fixes: 14131f2f98ac3 ("tracing: implement trace_clock_*() APIs") # where the bug happened Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212761 Signed-off-by: Steven Rostedt (VMware)

Merge tag 'net-next-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2021-04-29T18:57:23+00:00

Pull networking updates from Jakub Kicinski: "Core: - bpf: - allow bpf programs calling kernel functions (initially to reuse TCP congestion control implementations) - enable task local storage for tracing programs - remove the need to store per-task state in hash maps, and allow tracing programs access to task local storage previously added for BPF_LSM - add bpf_for_each_map_elem() helper, allowing programs to walk all map elements in a more robust and easier to verify fashion - sockmap: support UDP and cross-protocol BPF_SK_SKB_VERDICT redirection - lpm: add support for batched ops in LPM trie - add BTF_KIND_FLOAT support - mostly to allow use of BTF on s390 which has floats in its headers files - improve BPF syscall documentation and extend the use of kdoc parsing scripts we already employ for bpf-helpers - libbpf, bpftool: support static linking of BPF ELF files - improve support for encapsulation of L2 packets - xdp: restructure redirect actions to avoid a runtime lookup, improving performance by 4-8% in microbenchmarks - xsk: build skb by page (aka generic zerocopy xmit) - improve performance of software AF_XDP path by 33% for devices which don't need headers in the linear skb part (e.g. virtio) - nexthop: resilient next-hop groups - improve path stability on next-hops group changes (incl. offload for mlxsw) - ipv6: segment routing: add support for IPv4 decapsulation - icmp: add support for RFC 8335 extended PROBE messages - inet: use bigger hash table for IP ID generation - tcp: deal better with delayed TX completions - make sure we don't give up on fast TCP retransmissions only because driver is slow in reporting that it completed transmitting the original - tcp: reorder tcp_congestion_ops for better cache locality - mptcp: - add sockopt support for common TCP options - add support for common TCP msg flags - include multiple address ids in RM_ADDR - add reset option support for resetting one subflow - udp: GRO L4 improvements - improve 'forward' / 'frag_list' co-existence with UDP tunnel GRO, allowing the first to take place correctly even for encapsulated UDP traffic - micro-optimize dev_gro_receive() and flow dissection, avoid retpoline overhead on VLAN and TEB GRO - use less memory for sysctls, add a new sysctl type, to allow using u8 instead of "int" and "long" and shrink networking sysctls - veth: allow GRO without XDP - this allows aggregating UDP packets before handing them off to routing, bridge, OvS, etc. - allow specifing ifindex when device is moved to another namespace - netfilter: - nft_socket: add support for cgroupsv2 - nftables: add catch-all set element - special element used to define a default action in case normal lookup missed - use net_generic infra in many modules to avoid allocating per-ns memory unnecessarily - xps: improve the xps handling to avoid potential out-of-bound accesses and use-after-free when XPS change race with other re-configuration under traffic - add a config knob to turn off per-cpu netdev refcnt to catch underflows in testing Device APIs: - add WWAN subsystem to organize the WWAN interfaces better and hopefully start driving towards more unified and vendor- independent APIs - ethtool: - add interface for reading IEEE MIB stats (incl. mlx5 and bnxt support) - allow network drivers to dump arbitrary SFP EEPROM data, current offset+length API was a poor fit for modern SFP which define EEPROM in terms of pages (incl. mlx5 support) - act_police, flow_offload: add support for packet-per-second policing (incl. offload for nfp) - psample: add additional metadata attributes like transit delay for packets sampled from switch HW (and corresponding egress and policy-based sampling in the mlxsw driver) - dsa: improve support for sandwiched LAGs with bridge and DSA - netfilter: - flowtable: use direct xmit in topologies with IP forwarding, bridging, vlans etc. - nftables: counter hardware offload support - Bluetooth: - improvements for firmware download w/ Intel devices - add support for reading AOSP vendor capabilities - add support for virtio transport driver - mac80211: - allow concurrent monitor iface and ethernet rx decap - set priority and queue mapping for injected frames - phy: add support for Clause-45 PHY Loopback - pci/iov: add sysfs MSI-X vector assignment interface to distribute MSI-X resources to VFs (incl. mlx5 support) New hardware/drivers: - dsa: mv88e6xxx: add support for Marvell mv88e6393x - 11-port Ethernet switch with 8x 1-Gigabit Ethernet and 3x 10-Gigabit interfaces. - dsa: support for legacy Broadcom tags used on BCM5325, BCM5365 and BCM63xx switches - Microchip KSZ8863 and KSZ8873; 3x 10/100Mbps Ethernet switches - ath11k: support for QCN9074 a 802.11ax device - Bluetooth: Broadcom BCM4330 and BMC4334 - phy: Marvell 88X2222 transceiver support - mdio: add BCM6368 MDIO mux bus controller - r8152: support RTL8153 and RTL8156 (USB Ethernet) chips - mana: driver for Microsoft Azure Network Adapter (MANA) - Actions Semi Owl Ethernet MAC - can: driver for ETAS ES58X CAN/USB interfaces Pure driver changes: - add XDP support to: enetc, igc, stmmac - add AF_XDP support to: stmmac - virtio: - page_to_skb() use build_skb when there's sufficient tailroom (21% improvement for 1000B UDP frames) - support XDP even without dedicated Tx queues - share the Tx queues with the stack when necessary - mlx5: - flow rules: add support for mirroring with conntrack, matching on ICMP, GTP, flex filters and more - support packet sampling with flow offloads - persist uplink representor netdev across eswitch mode changes - allow coexistence of CQE compression and HW time-stamping - add ethtool extended link error state reporting - ice, iavf: support flow filters, UDP Segmentation Offload - dpaa2-switch: - move the driver out of staging - add spanning tree (STP) support - add rx copybreak support - add tc flower hardware offload on ingress traffic - ionic: - implement Rx page reuse - support HW PTP time-stamping - octeon: support TC hardware offloads - flower matching on ingress and egress ratelimitting. - stmmac: - add RX frame steering based on VLAN priority in tc flower - support frame preemption (FPE) - intel: add cross time-stamping freq difference adjustment - ocelot: - support forwarding of MRP frames in HW - support multiple bridges - support PTP Sync one-step timestamping - dsa: mv88e6xxx, dpaa2-switch: offload bridge port flags like learning, flooding etc. - ipa: add IPA v4.5, v4.9 and v4.11 support (Qualcomm SDX55, SM8350, SC7280 SoCs) - mt7601u: enable TDLS support - mt76: - add support for 802.3 rx frames (mt7915/mt7615) - mt7915 flash pre-calibration support - mt7921/mt7663 runtime power management fixes" * tag 'net-next-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2451 commits) net: selftest: fix build issue if INET is disabled net: netrom: nr_in: Remove redundant assignment to ns net: tun: Remove redundant assignment to ret net: phy: marvell: add downshift support for M88E1240 net: dsa: ksz: Make reg_mib_cnt a u8 as it never exceeds 255 net/sched: act_ct: Remove redundant ct get and check icmp: standardize naming of RFC 8335 PROBE constants bpf, selftests: Update array map tests for per-cpu batched ops bpf: Add batched ops support for percpu array bpf: Implement formatted output helpers with bstr_printf seq_file: Add a seq_bprintf function sfc: adjust efx->xdp_tx_queue_count with the real number of initialized queues net:nfc:digital: Fix a double free in digital_tg_recv_dep_req net: fix a concurrency bug in l2tp_tunnel_register() net/smc: Remove redundant assignment to rc mpls: Remove redundant assignment to err llc2: Remove redundant assignment to rc net/tls: Remove redundant initialization of record rds: Remove redundant assignment to nr_sig dt-bindings: net: mdio-gpio: add compatible for microchip,mdio-smi0 ...

tracing: Map all PIDs to command lines

2021-04-28T17:20:04+00:00

The default max PID is set by PID_MAX_DEFAULT, and the tracing infrastructure uses this number to map PIDs to the comm names of the tasks, such output of the trace can show names from the recorded PIDs in the ring buffer. This mapping is also exported to user space via the "saved_cmdlines" file in the tracefs directory. But currently the mapping expects the PIDs to be less than PID_MAX_DEFAULT, which is the default maximum and not the real maximum. Recently, systemd will increases the maximum value of a PID on the system, and when tasks are traced that have a PID higher than PID_MAX_DEFAULT, its comm is not recorded. This leads to the entire trace to have "<...>" as the comm name, which is pretty useless. Instead, keep the array mapping the size of PID_MAX_DEFAULT, but instead of just mapping the index to the comm, map a mask of the PID (PID_MAX_DEFAULT - 1) to the comm, and find the full PID from the map_cmdline_to_pid array (that already exists). This bug goes back to the beginning of ftrace, but hasn't been an issue until user space started increasing the maximum value of PIDs. Link: https://lkml.kernel.org/r/20210427113207.3c601884@gandalf.local.home Cc: stable@vger.kernel.org Fixes: bc0c38d139ec7 ("ftrace: latency tracer infrastructure") Signed-off-by: Steven Rostedt (VMware)

bpf: Implement formatted output helpers with bstr_printf

2021-04-27T22:56:31+00:00

BPF has three formatted output helpers: bpf_trace_printk, bpf_seq_printf and bpf_snprintf. Their signatures specify that all arguments are provided from the BPF world as u64s (in an array or as registers). All of these helpers are currently implemented by calling functions such as snprintf() whose signatures take a variable number of arguments, then placed in a va_list by the compiler to call vsnprintf(). "d9c9e4db bpf: Factorize bpf_trace_printk and bpf_seq_printf" introduced a bpf_printf_prepare function that fills an array of u64 sanitized arguments with an array of "modifiers" which indicate what the "real" size of each argument should be (given by the format specifier). The BPF_CAST_FMT_ARG macro consumes these arrays and casts each argument to its real size. However, the C promotion rules implicitely cast them all back to u64s. Therefore, the arguments given to snprintf are u64s and the va_list constructed by the compiler will use 64 bits for each argument. On 64 bit machines, this happens to work well because 32 bit arguments in va_lists need to occupy 64 bits anyway, but on 32 bit architectures this breaks the layout of the va_list expected by the called function and mangles values. In "88a5c690b6 bpf: fix bpf_trace_printk on 32 bit archs", this problem had been solved for bpf_trace_printk only with a "horrid workaround" that emitted multiple calls to trace_printk where each call had different argument types and generated different va_list layouts. One of the call would be dynamically chosen at runtime. This was ok with the 3 arguments that bpf_trace_printk takes but bpf_seq_printf and bpf_snprintf accept up to 12 arguments. Because this approach scales code exponentially, it is not a viable option anymore. Because the promotion rules are part of the language and because the construction of a va_list is an arch-specific ABI, it's best to just avoid variadic arguments and va_lists altogether. Thankfully the kernel's snprintf() has an alternative in the form of bstr_printf() that accepts arguments in a "binary buffer representation". These binary buffers are currently created by vbin_printf and used in the tracing subsystem to split the cost of printing into two parts: a fast one that only dereferences and remembers values, and a slower one, called later, that does the pretty-printing. This patch refactors bpf_printf_prepare to construct binary buffers of arguments consumable by bstr_printf() instead of arrays of arguments and modifiers. This gets rid of BPF_CAST_FMT_ARG and greatly simplifies the bpf_printf_prepare usage but there are a few gotchas that change how bpf_printf_prepare needs to do things. Currently, bpf_printf_prepare uses a per cpu temporary buffer as a generic storage for strings and IP addresses. With this refactoring, the temporary buffers now holds all the arguments in a structured binary format. To comply with the format expected by bstr_printf, certain format specifiers also need to be pre-formatted: %pB and %pi6/%pi4/%pI4/%pI6. Because vsnprintf subroutines for these specifiers are hard to expose, we pre-format these arguments with calls to snprintf(). Reported-by: Rasmus Villemoes Signed-off-by: Florent Revest Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210427174313.860948-3-revest@chromium.org

bpf: Lock bpf_trace_printk's tmp buf before it is written to

2021-04-27T15:04:34+00:00

bpf_trace_printk uses a shared static buffer to hold strings before they are printed. A recent refactoring moved the locking of that buffer after it gets filled by mistake. Fixes: d9c9e4db186a ("bpf: Factorize bpf_trace_printk and bpf_seq_printf") Reported-by: Rasmus Villemoes Signed-off-by: Florent Revest Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210427112958.773132-1-revest@chromium.org

Merge tag 'irq-core-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-04-26T16:43:16+00:00

Pull irq updates from Thomas Gleixner: "The usual updates from the irq departement: Core changes: - Provide IRQF_NO_AUTOEN as a flag for request*_irq() so drivers can be cleaned up which either use a seperate mechanism to prevent auto-enable at request time or have a racy mechanism which disables the interrupt right after request. - Get rid of the last usage of irq_create_identity_mapping() and remove the interface. - An overhaul of tasklet_disable(). Most usage sites of tasklet_disable() are in task context and usually in cleanup, teardown code pathes. tasklet_disable() spinwaits for a tasklet which is currently executed. That's not only a problem for PREEMPT_RT where this can lead to a live lock when the disabling task preempts the softirq thread. It's also problematic in context of virtualization when the vCPU which runs the tasklet is scheduled out and the disabling code has to spin wait until it's scheduled back in. There are a few code pathes which invoke tasklet_disable() from non-sleepable context. For these a new disable variant which still spinwaits is provided which allows to switch tasklet_disable() to a sleep wait mechanism. For the atomic use cases this does not solve the live lock issue on PREEMPT_RT. That is mitigated by blocking on the RT specific softirq lock. - The PREEMPT_RT specific implementation of softirq processing and local_bh_disable/enable(). On RT enabled kernels soft interrupt processing happens always in task context and all interrupt handlers, which are not explicitly marked to be invoked in hard interrupt context are forced into task context as well. This allows to protect against softirq processing with a per CPU lock, which in turn allows to make BH disabled regions preemptible. Most of the softirq handling code is still shared. The RT/non-RT specific differences are addressed with a set of inline functions which provide the context specific functionality. The local_bh_disable() / local_bh_enable() mechanism are obviously seperate. - The usual set of small improvements and cleanups Driver changes: - New drivers for Nuvoton WPCM450 and DT 79rc3243x interrupt controllers - Extended functionality for MStar, STM32 and SC7280 irq chips - Enhanced robustness for ARM GICv3/4.1 drivers - The usual set of cleanups and improvements all over the place" * tag 'irq-core-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) irqchip/xilinx: Expose Kconfig option for Zynq/ZynqMP irqchip/gic-v3: Do not enable irqs when handling spurious interrups dt-bindings: interrupt-controller: Add IDT 79RC3243x Interrupt Controller irqchip: Add support for IDT 79rc3243x interrupt controller irqdomain: Drop references to recusive irqdomain setup irqdomain: Get rid of irq_create_strict_mappings() irqchip/jcore-aic: Kill use of irq_create_strict_mappings() ARM: PXA: Kill use of irq_create_strict_mappings() irqchip/gic-v4.1: Disable vSGI upon (GIC CPUIF < v4.1) detection irqchip/tb10x: Use 'fallthrough' to eliminate a warning genirq: Reduce irqdebug cacheline bouncing kernel: Initialize cpumask before parsing irqchip/wpcm450: Drop COMPILE_TEST irqchip/irq-mst: Support polarity configuration irqchip: Add driver for WPCM450 interrupt controller dt-bindings: interrupt-controller: Add nuvoton, wpcm450-aic dt-bindings: qcom,pdc: Add compatible for sc7280 irqchip/stm32: Add usart instances exti direct event support irqchip/gic-v3: Fix OF_BAD_ADDR error handling irqchip/sifive-plic: Mark two global variables __ro_after_init ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2021-04-26T01:02:32+00:00

Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-04-23 The following pull-request contains BPF updates for your *net-next* tree. We've added 69 non-merge commits during the last 22 day(s) which contain a total of 69 files changed, 3141 insertions(+), 866 deletions(-). The main changes are: 1) Add BPF static linker support for extern resolution of global, from Andrii. 2) Refine retval for bpf_get_task_stack helper, from Dave. 3) Add a bpf_snprintf helper, from Florent. 4) A bunch of miscellaneous improvements from many developers. ==================== Signed-off-by: David S. Miller