summaryrefslogtreecommitdiffstats
path: root/Documentation/trace
Commit message (Collapse)AuthorAgeFilesLines
* tracing/timerlat: Print stacktrace in the IRQ handler if neededDaniel Bristot de Oliveira2022-05-261-2/+3
| | | | | | | | | | | | | | | If print_stack and stop_tracing_us are set, and stop_tracing_us is hit with latency higher than or equal to print_stack, print the stack at the IRQ handler as it is useful to define the root cause for the IRQ latency. Link: https://lkml.kernel.org/r/fd04530ce98ae9270e41bb124ee5bf67b05ecfed.1652175637.git.bristot@kernel.org Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* tracing: Add documentation for trace clock taiKurt Kanzenbach2022-04-271-0/+12
| | | | | | | | | | Add documentation for newly introduced trace clock "tai". This clock corresponds to CLOCK_TAI. Link: https://lkml.kernel.org/r/20220414091805.89667-4-kurt@linutronix.de Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* Merge tag 'trace-v5.18-2' of ↵Linus Torvalds2022-04-031-11/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: - Rename the staging files to give them some meaning. Just stage1,stag2,etc, does not show what they are for - Check for NULL from allocation in bootconfig - Hold event mutex for dyn_event call in user events - Mark user events to broken (to work on the API) - Remove eBPF updates from user events - Remove user events from uapi header to keep it from being installed. - Move ftrace_graph_is_dead() into inline as it is called from hot paths and also convert it into a static branch. * tag 'trace-v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Move user_events.h temporarily out of include/uapi ftrace: Make ftrace_graph_is_dead() a static branch tracing: Set user_events to BROKEN tracing/user_events: Remove eBPF interfaces tracing/user_events: Hold event_mutex during dyn_event_add proc: bootconfig: Add null pointer check tracing: Rename the staging files for trace_events
| * tracing/user_events: Remove eBPF interfacesBeau Belgrave2022-04-021-11/+3
| | | | | | | | | | | | | | | | | | | | | | | | Remove eBPF interfaces within user_events to ensure they are fully reviewed. Link: https://lore.kernel.org/all/20220329165718.GA10381@kbox/ Link: https://lkml.kernel.org/r/20220329173051.10087-1-beaub@linux.microsoft.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* | Merge tag 'net-next-5.18' of ↵Linus Torvalds2022-03-242-0/+175
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * docs: fprobe: Add fprobe description to ftrace-use.rstMasami Hiramatsu2022-03-172-0/+175
| | | | | | | | | | | | | | | | | | | | | | Add a documentation of fprobe for the user who needs this interface. 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/164735294272.1084943.12372175959382037397.stgit@devnote2
* | Merge tag 'trace-v5.18' of ↵Linus Torvalds2022-03-232-0/+217
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - New user_events interface. User space can register an event with the kernel describing the format of the event. Then it will receive a byte in a page mapping that it can check against. A privileged task can then enable that event like any other event, which will change the mapped byte to true, telling the user space application to start writing the event to the tracing buffer. - Add new "ftrace_boot_snapshot" kernel command line parameter. When set, the tracing buffer will be saved in the snapshot buffer at boot up when the kernel hands things over to user space. This will keep the traces that happened at boot up available even if user space boot up has tracing as well. - Have TRACE_EVENT_ENUM() also update trace event field type descriptions. Thus if a static array defines its size with an enum, the user space trace event parsers can still know how to parse that array. - Add new TRACE_CUSTOM_EVENT() macro. This acts the same as the TRACE_EVENT() macro, but will attach to an existing tracepoint. This will make one tracepoint be able to trace different content and not be stuck at only what the original TRACE_EVENT() macro exports. - Fixes to tracing error logging. - Better saving of cmdlines to PIDs when tracing (use the wakeup events for mapping). * tag 'trace-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits) tracing: Have type enum modifications copy the strings user_events: Add trace event call as root for low permission cases tracing/user_events: Use alloc_pages instead of kzalloc() for register pages tracing: Add snapshot at end of kernel boot up tracing: Have TRACE_DEFINE_ENUM affect trace event types as well tracing: Fix strncpy warning in trace_events_synth.c user_events: Prevent dyn_event delete racing with ioctl add/delete tracing: Add TRACE_CUSTOM_EVENT() macro tracing: Move the defines to create TRACE_EVENTS into their own files tracing: Add sample code for custom trace events tracing: Allow custom events to be added to the tracefs directory tracing: Fix last_cmd_set() string management in histogram code user_events: Fix potential uninitialized pointer while parsing field tracing: Fix allocation of last_cmd in last_cmd_set() user_events: Add documentation file user_events: Add sample code for typical usage user_events: Add self-test for validator boundaries user_events: Add self-test for perf_event integration user_events: Add self-test for dynamic_events integration user_events: Add self-test for ftrace integration ...
| * | user_events: Add documentation fileBeau Belgrave2022-02-102-0/+217
| |/ | | | | | | | | | | | | | | | | | | | | Add a documentation file about user_events with example code, etc. explaining how it may be used. Link: https://lkml.kernel.org/r/20220118204326.2169-13-beaub@linux.microsoft.com Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
* / docs: Remove duplicated words in trace/osnoise-tracerOscar Shiang2022-02-241-2/+2
|/ | | | | | | | | | | There are 2 duplicated words found in osnoise tracer documentation. This patch removes them. Signed-off-by: Oscar Shiang <oscar0225@livemail.tw> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Link: https://lore.kernel.org/r/TYCP286MB1913117487F390E3BCE38B15A1399@TYCP286MB1913.JPNP286.PROD.OUTLOOK.COM Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Merge tag 'docs-5.17-2' of git://git.lwn.net/linuxLinus Torvalds2022-01-221-1/+1
|\ | | | | | | | | | | | | | | | | | | Pull documentation fixes from Jonathan Corbet: "Three small documentation fixes" * tag 'docs-5.17-2' of git://git.lwn.net/linux: Documentation: fix firewire.rst ABI file path error docs: ftrace: fix ambiguous sentence docs: staging/tee.rst: fix two typos found while reading
| * docs: ftrace: fix ambiguous sentenceHuichun Feng2022-01-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | The sentence looks ambiguous, rephrase it by adding ", there". Signed-off-by: Huichun Feng <foxhoundsk.tw@gmail.com> Signed-off-by: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw> Signed-off-by: Chun-Hung Tseng <henrybear327@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20220111052000.2675944-1-foxhoundsk.tw@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* | Merge tag 'trace-v5.17' of ↵Linus Torvalds2022-01-161-0/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New: - The Real Time Linux Analysis (RTLA) tool is added to the tools directory. - Can safely filter on user space pointers with: field.ustring ~ "match-string" - eprobes can now be filtered like any other event. - trace_marker(_raw) now uses stream_open() to allow multiple threads to safely write to it. Note, this could possibly break existing user space, but we will not know until we hear about it, and then can revert the change if need be. - New field in events to display when bottom halfs are disabled. - Sorting of the ftrace functions are now done at compile time instead of at bootup. Infrastructure changes to support future efforts: - Added __rel_loc type for trace events. Similar to __data_loc but the offset to the dynamic data is based off of the location of the descriptor and not the beginning of the event. Needed for user defined events. - Some simplification of event trigger code. - Make synthetic events process its callback better to not hinder other event callbacks that are registered. Needed for user defined events. And other small fixes and cleanups" * tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits) tracing: Add ustring operation to filtering string pointers rtla: Add rtla timerlat hist documentation rtla: Add rtla timerlat top documentation rtla: Add rtla timerlat documentation rtla: Add rtla osnoise hist documentation rtla: Add rtla osnoise top documentation rtla: Add rtla osnoise man page rtla: Add Documentation rtla/timerlat: Add timerlat hist mode rtla: Add timerlat tool and timelart top mode rtla/osnoise: Add the hist mode rtla/osnoise: Add osnoise top mode rtla: Add osnoise tool rtla: Helper functions for rtla rtla: Real-Time Linux Analysis tool tracing/osnoise: Properly unhook events if start_per_cpu_kthreads() fails tracing: Remove duplicate warnings when calling trace_create_file() tracing/kprobes: 'nmissed' not showed correctly for kretprobe tracing: Add test for user space strings when filtering on string pointers tracing: Have syscall trace events use trace_event_buffer_lock_reserve() ...
| * | tracing: Add ustring operation to filtering string pointersSteven Rostedt2022-01-141-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since referencing user space pointers is special, if the user wants to filter on a field that is a pointer to user space, then they need to specify it. Add a ".ustring" attribute to the field name for filters to state that the field is pointing to user space such that the kernel can take the appropriate action to read that pointer. Link: https://lore.kernel.org/all/yt9d8rvmt2jq.fsf@linux.ibm.com/ Fixes: 77360f9bbc7e ("tracing: Add test for user space strings when filtering on string pointers") Tested-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| * | tracing: Add test for user space strings when filtering on string pointersSteven Rostedt2022-01-131-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pingfan reported that the following causes a fault: echo "filename ~ \"cpu\"" > events/syscalls/sys_enter_openat/filter echo 1 > events/syscalls/sys_enter_at/enable The reason is that trace event filter treats the user space pointer defined by "filename" as a normal pointer to compare against the "cpu" string. The following bug happened: kvm-03-guest16 login: [72198.026181] BUG: unable to handle page fault for address: 00007fffaae8ef60 #PF: supervisor read access in kernel mode #PF: error_code(0x0001) - permissions violation PGD 80000001008b7067 P4D 80000001008b7067 PUD 2393f1067 PMD 2393ec067 PTE 8000000108f47867 Oops: 0001 [#1] PREEMPT SMP PTI CPU: 1 PID: 1 Comm: systemd Kdump: loaded Not tainted 5.14.0-32.el9.x86_64 #1 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:strlen+0x0/0x20 Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31 RSP: 0018:ffffb5b900013e48 EFLAGS: 00010246 RAX: 0000000000000018 RBX: ffff8fc1c49ede00 RCX: 0000000000000000 RDX: 0000000000000020 RSI: ffff8fc1c02d601c RDI: 00007fffaae8ef60 RBP: 00007fffaae8ef60 R08: 0005034f4ddb8ea4 R09: 0000000000000000 R10: ffff8fc1c02d601c R11: 0000000000000000 R12: ffff8fc1c8a6e380 R13: 0000000000000000 R14: ffff8fc1c02d6010 R15: ffff8fc1c00453c0 FS: 00007fa86123db40(0000) GS:ffff8fc2ffd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffaae8ef60 CR3: 0000000102880001 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: filter_pred_pchar+0x18/0x40 filter_match_preds+0x31/0x70 ftrace_syscall_enter+0x27a/0x2c0 syscall_trace_enter.constprop.0+0x1aa/0x1d0 do_syscall_64+0x16/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa861d88664 The above happened because the kernel tried to access user space directly and triggered a "supervisor read access in kernel mode" fault. Worse yet, the memory could not even be loaded yet, and a SEGFAULT could happen as well. This could be true for kernel space accessing as well. To be even more robust, test both kernel and user space strings. If the string fails to read, then simply have the filter fail. Note, TASK_SIZE is used to determine if the pointer is user or kernel space and the appropriate strncpy_from_kernel/user_nofault() function is used to copy the memory. For some architectures, the compare to TASK_SIZE may always pick user space or kernel space. If it gets it wrong, the only thing is that the filter will fail to match. In the future, this needs to be fixed to have the event denote which should be used. But failing a filter is much better than panicing the machine, and that can be solved later. Link: https://lore.kernel.org/all/20220107044951.22080-1-kernelfans@gmail.com/ Link: https://lkml.kernel.org/r/20220110115532.536088fd@gandalf.local.home Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Reported-by: Pingfan Liu <kernelfans@gmail.com> Tested-by: Pingfan Liu <kernelfans@gmail.com> Fixes: 87a342f5db69d ("tracing/filters: Support filtering for char * strings") Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | Merge tag 'char-misc-5.17-rc1' of ↵Linus Torvalds2022-01-141-14/+64
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver updates from Greg KH: "Here is the large set of char, misc, and other "small" driver subsystem changes for 5.17-rc1. Lots of different things are in here for char/misc drivers such as: - habanalabs driver updates - mei driver updates - lkdtm driver updates - vmw_vmci driver updates - android binder driver updates - other small char/misc driver updates Also smaller driver subsystems have also been updated, including: - fpga subsystem updates - iio subsystem updates - soundwire subsystem updates - extcon subsystem updates - gnss subsystem updates - phy subsystem updates - coresight subsystem updates - firmware subsystem updates - comedi subsystem updates - mhi subsystem updates - speakup subsystem updates - rapidio subsystem updates - spmi subsystem updates - virtual driver updates - counter subsystem updates Too many individual changes to summarize, the shortlog contains the full details. All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (406 commits) counter: 104-quad-8: Fix use-after-free by quad8_irq_handler dt-bindings: mux: Document mux-states property dt-bindings: ti-serdes-mux: Add defines for J721S2 SoC counter: remove old and now unused registration API counter: ti-eqep: Convert to new counter registration counter: stm32-lptimer-cnt: Convert to new counter registration counter: stm32-timer-cnt: Convert to new counter registration counter: microchip-tcb-capture: Convert to new counter registration counter: ftm-quaddec: Convert to new counter registration counter: intel-qep: Convert to new counter registration counter: interrupt-cnt: Convert to new counter registration counter: 104-quad-8: Convert to new counter registration counter: Update documentation for new counter registration functions counter: Provide alternative counter registration functions counter: stm32-timer-cnt: Convert to counter_priv() wrapper counter: stm32-lptimer-cnt: Convert to counter_priv() wrapper counter: ti-eqep: Convert to counter_priv() wrapper counter: ftm-quaddec: Convert to counter_priv() wrapper counter: intel-qep: Convert to counter_priv() wrapper counter: microchip-tcb-capture: Convert to counter_priv() wrapper ...
| * | Merge tag 'coresight-next-v5.17' of ↵Greg Kroah-Hartman2021-12-211-14/+64
| |\ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gitolite.kernel.org:pub/scm/linux/kernel/git/coresight/linux into char-misc-next Mathieu writes: Coresight changes for v5.17 This pull request includes: - A patch that uses devm_bitmap_zalloc() instead of the open-coded equivalent. - Work to make coresight complex configuration loadable via modules. - Some coresight documentation updates. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> * tag 'coresight-next-v5.17' of gitolite.kernel.org:pub/scm/linux/kernel/git/coresight/linux: coresight: core: Fix typo in a comment Documentation: coresight: Update coresight configuration docs coresight: configfs: Allow configfs to activate configuration coresight: syscfg: Example CoreSight configuration loadable module coresight: syscfg: Update load API for config loadable modules coresight: configuration: Update API to permit dynamic load/unload coresight: configuration: Update API to introduce load owner concept Documentation: coresight: Fix documentation issue coresight: Use devm_bitmap_zalloc when applicable
| | * Documentation: coresight: Update coresight configuration docsMike Leach2021-11-261-3/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update the CoreSight System Configuration document to cover the use of loadable modules to add configurations and features to the system. Signed-off-by: Mike Leach <mike.leach@linaro.org> Link: https://lore.kernel.org/r/20211124200038.28662-7-mike.leach@linaro.org Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
| | * Documentation: coresight: Fix documentation issueMike Leach2021-11-181-11/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the description of the directories and attributes used in cs_etm as used by perf. Drop the references to the 'configurations' sub-directory which had been removed in an earlier version of the patchset. Fixes: f71cd93d5ea4 ("Documentation: coresight: Add documentation for CoreSight config") Reported-by: German Gomex <german.gomez@arm.com> Signed-off-by: Mike Leach <mike.leach@linaro.org> Link: https://lore.kernel.org/r/20211117164220.14883-1-mike.leach@linaro.org Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
* | | docs/trace: fix a label of boottime-traceYanteng Si2021-12-101-3/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 559789539255 ("Documentation: tracing: Add histogram syntax to boot-time tracing") introduced a warning: linux/Documentation/trace/boottime-trace.rst:136: WARNING: undefined label: histogram (if the link has no caption the label must precede a section header) Replace with: (path) Signed-off-by: Yanteng Si <siyanteng@loongson.cn> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 559789539255 ("Documentation: tracing: Add histogram syntax to boot-time tracing") Link: https://lore.kernel.org/r/20211210041536.1446734-1-siyanteng@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* / docs: ftrace: fix the wrong path of tracefsZhaoyu Liu2021-11-151-5/+4
|/ | | | | | | | | | Delete "tracing" due to it has been included in /proc/mounts. Delete "echo nop > $tracefs/tracing/current_tracer", maybe this command is redundant. Signed-off-by: Zhaoyu Liu <zackary.liu.pro@gmail.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* tracing/histogram: Update division by 0 documentationKalesh Singh2021-11-011-1/+2
| | | | | | | | | | | | | | If the divisor is a constant and zero, the undeifned case can be detected and an error returned instead of -1. Link: https://lkml.kernel.org/r/20211029183339.3216491-3-kaleshsingh@google.com Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing/histogram: Fix documentation inline emphasis warningKalesh Singh2021-10-281-1/+1
| | | | | | | | | | | | | | | | | This fixes the warning: Documentation/trace/histogram.rst:1766: WARNING: Inline emphasis start-string without end-string The issue was caused by an unescaped '*' character. Link: https://lore.kernel.org/all/20211028170548.2597449-1-kaleshsingh@google.com/T/#m77da47432f5cc6521d4294ffdb9621949cc35d04 Link: https://lkml.kernel.org/r/20211028170548.2597449-1-kaleshsingh@google.com Fixes: 2d2f6d4b8ce7 ("tracing/histogram: Document expression arithmetic and constants") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing/histogram: Document expression arithmetic and constantsKalesh Singh2021-10-261-0/+14
| | | | | | | | | | | | | | Histogram expressions now support division, and multiplication in addition to the already supported subtraction and addition operators. Numeric constants can also be used in a hist trigger expressions or assigned to a variable and used by refernce in an expression. Link: https://lkml.kernel.org/r/20211025200852.3002369-9-kaleshsingh@google.com Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* docs, kprobes: Remove invalid URL and add new referenceTiezhu Yang2021-10-261-1/+1
| | | | | | | | | | | | | | The following reference is invalid, remove it. https://www.ibm.com/developerworks/library/l-kprobes/index.html Add the following new reference "An introduction to KProbes": https://lwn.net/Articles/132196/ Link: https://lkml.kernel.org/r/1635213091-24387-3-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* tracing/doc: Fix typos on the timerlat tracer documentationDaniel Bristot de Oliveira2021-10-251-12/+12
| | | | | | | | | | | | | | | | | | | | Fixes a series of typos in the timerlat doc. Link: https://lkml.kernel.org/r/d3763eb376603890baab908141de6660ba18fff8.1634308385.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Fixes: a955d7eac177 ("trace: Add timerlat tracer") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* Merge tag 'trace-v5.15' of ↵Linus Torvalds2021-09-052-20/+175
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT - bootconfig can now start histograms - bootconfig supports group/all enabling - histograms now can put values in linear size buckets - execnames can be passed to synthetic events - introduce "event probes" that attach to other events and can retrieve data from pointers of fields, or record fields as different types (a pointer to a string as a string instead of just a hex number) - various fixes and clean ups * tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits) tracing/doc: Fix table format in histogram code selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes selftests/ftrace: Add selftest for testing eprobe events on synthetic events selftests/ftrace: Add test case to test adding and removing of event probe selftests/ftrace: Fix requirement check of README file selftests/ftrace: Add clear_dynamic_events() to test cases tracing: Add a probe that attaches to trace events tracing/probes: Reject events which have the same name of existing one tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs tracing/probe: Change traceprobe_set_print_fmt() to take a type tracing/probes: Use struct_size() instead of defining custom macros tracing/probes: Allow for dot delimiter as well as slash for system names tracing/probe: Have traceprobe_parse_probe_arg() take a const arg tracing: Have dynamic events have a ref counter tracing: Add DYNAMIC flag for dynamic events tracing: Replace deprecated CPU-hotplug functions. MAINTAINERS: Add an entry for os noise/latency tracepoint: Fix kerneldoc comments bootconfig/tracing/ktest: Update ktest example for boot-time tracing tools/bootconfig: Use per-group/all enable option in ftrace2bconf script ...
| * tracing/doc: Fix table format in histogram codeSteven Rostedt (VMware)2021-08-241-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | The addition of the buckets conversion for the histogram code, updated the documentation table of available conversions, but did not update the format to accommodate the extra size needed to cover the description. Link: https://lkml.kernel.org/r/20210823100007.71ce2ba9@oasis.local.home Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * Documentation: tracing: Add histogram syntax to boot-time tracingMasami Hiramatsu2021-08-161-5/+80
| | | | | | | | | | | | | | | | | | | | | | Add the documentation about histogram syntax in boot-time tracing. This will allow user to write the histogram setting in a structured parameters. Link: https://lkml.kernel.org/r/162856127129.203126.15551542847575916525.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * tracing/histogram: Update the documentation for the buckets modifierSteven Rostedt (VMware)2021-08-161-6/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | Update both the tracefs README file as well as the histogram.rst to include an explanation of what the buckets modifier is and how to use it. Include an example with the wakeup_latency example for both log2 and the buckets modifiers as there was no existing log2 example. Link: https://lkml.kernel.org/r/20210707213922.167218794@goodmis.org Acked-by: Namhyung Kim <namhyung@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | Merge tag 'char-misc-5.15-rc1' of ↵Linus Torvalds2021-09-012-0/+259
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc driver updates from Greg KH: "Here is the big set of char/misc driver changes for 5.15-rc1. Lots of different driver subsystems are being updated in here, notably: - mhi subsystem update - fpga subsystem update - coresight/hwtracing subsystem update - interconnect subsystem update - nvmem subsystem update - parport drivers update - phy subsystem update - soundwire subsystem update and there are some other char/misc drivers being updated as well: - binder driver additions - new misc drivers - lkdtm driver updates - mei driver updates - sram driver updates - other minor driver updates. Note, there are no habanalabs driver updates in this pull request, that will probably come later before -rc1 is out in a different request. All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (169 commits) Revert "bus: mhi: Add inbound buffers allocation flag" misc/pvpanic: fix set driver data VMCI: fix NULL pointer dereference when unmapping queue pair char: mware: fix returnvar.cocci warnings parport: remove non-zero check on count soundwire: cadence: do not extend reset delay soundwire: intel: conditionally exit clock stop mode on system suspend soundwire: intel: skip suspend/resume/wake when link was not started soundwire: intel: fix potential race condition during power down phy: qcom-qmp: Add support for SM6115 UFS phy dt-bindings: phy: qcom,qmp: Add SM6115 UFS PHY bindings phy: qmp: Provide unique clock names for DP clocks lkdtm: remove IDE_CORE_CP crashpoint lkdtm: replace SCSI_DISPATCH_CMD with SCSI_QUEUE_RQ coresight: Replace deprecated CPU-hotplug functions. Documentation: coresight: Add documentation for CoreSight config coresight: syscfg: Add initial configfs support coresight: config: Add preloaded configurations coresight: etm4x: Add complex configuration handlers to etmv4 coresight: etm-perf: Update to activate selected configuration ...
| * | Documentation: coresight: Add documentation for CoreSight configMike Leach2021-08-182-0/+259
| |/ | | | | | | | | | | | | | | | | | | | | | | | | Adds documentation for the CoreSight System configuration manager. Link: https://lore.kernel.org/r/20210723165444.1048-11-mike.leach@linaro.org [Fixed coresight-config.rst documentation link] Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Mike Leach <mike.leach@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20210818194022.379573-11-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* / Documentation: Replace deprecated CPU-hotplug functions.Sebastian Andrzej Siewior2021-08-281-1/+1
|/ | | | | | | | | | | | | The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Update the documentation accordingly. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210803141621.780504-2-bigeasy@linutronix.de
* tracing/histogram: Rename "cpu" to "common_cpu"Steven Rostedt (VMware)2021-07-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the histogram logic allows the user to write "cpu" in as an event field, and it will record the CPU that the event happened on. The problem with this is that there's a lot of events that have "cpu" as a real field, and using "cpu" as the CPU it ran on, makes it impossible to run histograms on the "cpu" field of events. For example, if I want to have a histogram on the count of the workqueue_queue_work event on its cpu field, running: ># echo 'hist:keys=cpu' > events/workqueue/workqueue_queue_work/trigger Gives a misleading and wrong result. Change the command to "common_cpu" as no event should have "common_*" fields as that's a reserved name for fields used by all events. And this makes sense here as common_cpu would be a field used by all events. Now we can even do: ># echo 'hist:keys=common_cpu,cpu if cpu < 100' > events/workqueue/workqueue_queue_work/trigger ># cat events/workqueue/workqueue_queue_work/hist # event histogram # # trigger info: hist:keys=common_cpu,cpu:vals=hitcount:sort=hitcount:size=2048 if cpu < 100 [active] # { common_cpu: 0, cpu: 2 } hitcount: 1 { common_cpu: 0, cpu: 4 } hitcount: 1 { common_cpu: 7, cpu: 7 } hitcount: 1 { common_cpu: 0, cpu: 7 } hitcount: 1 { common_cpu: 0, cpu: 1 } hitcount: 1 { common_cpu: 0, cpu: 6 } hitcount: 2 { common_cpu: 0, cpu: 5 } hitcount: 2 { common_cpu: 1, cpu: 1 } hitcount: 4 { common_cpu: 6, cpu: 6 } hitcount: 4 { common_cpu: 5, cpu: 5 } hitcount: 14 { common_cpu: 4, cpu: 4 } hitcount: 26 { common_cpu: 0, cpu: 0 } hitcount: 39 { common_cpu: 2, cpu: 2 } hitcount: 184 Now for backward compatibility, I added a trick. If "cpu" is used, and the field is not found, it will fall back to "common_cpu" and work as it did before. This way, it will still work for old programs that use "cpu" to get the actual CPU, but if the event has a "cpu" as a field, it will get that event's "cpu" field, which is probably what it wants anyway. I updated the tracefs/README to include documentation about both the common_timestamp and the common_cpu. This way, if that text is present in the README, then an application can know that common_cpu is supported over just plain "cpu". Link: https://lkml.kernel.org/r/20210721110053.26b4f641@oasis.local.home Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: 8b7622bf94a44 ("tracing: Add cpu field for hist triggers") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* Merge tag 'trace-v5.14' of ↵Linus Torvalds2021-07-035-4/+350
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Added option for per CPU threads to the hwlat tracer - Have hwlat tracer handle hotplug CPUs - New tracer: osnoise, that detects latency caused by interrupts, softirqs and scheduling of other tasks. - Added timerlat tracer that creates a thread and measures in detail what sources of latency it has for wake ups. - Removed the "success" field of the sched_wakeup trace event. This has been hardcoded as "1" since 2015, no tooling should be looking at it now. If one exists, we can revert this commit, fix that tool and try to remove it again in the future. - tgid mapping fixed to handle more than PID_MAX_DEFAULT pids/tgids. - New boot command line option "tp_printk_stop", as tp_printk causes trace events to write to console. When user space starts, this can easily live lock the system. Having a boot option to stop just after boot up is useful to prevent that from happening. - Have ftrace_dump_on_oops boot command line option take numbers that match the numbers shown in /proc/sys/kernel/ftrace_dump_on_oops. - Bootconfig clean ups, fixes and enhancements. - New ktest script that tests bootconfig options. - Add tracepoint_probe_register_may_exist() to register a tracepoint without triggering a WARN*() if it already exists. BPF has a path from user space that can do this. All other paths are considered a bug. - Small clean ups and fixes * tag 'trace-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (49 commits) tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULT tracing: Simplify & fix saved_tgids logic treewide: Add missing semicolons to __assign_str uses tracing: Change variable type as bool for clean-up trace/timerlat: Fix indentation on timerlat_main() trace/osnoise: Make 'noise' variable s64 in run_osnoise() tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing tracing: Fix spelling in osnoise tracer "interferences" -> "interference" Documentation: Fix a typo on trace/osnoise-tracer trace/osnoise: Fix return value on osnoise_init_hotplug_support trace/osnoise: Make interval u64 on osnoise_main trace/osnoise: Fix 'no previous prototype' warnings tracing: Have osnoise_main() add a quiescent state for task rcu seq_buf: Make trace_seq_putmem_hex() support data longer than 8 seq_buf: Fix overflow in seq_buf_putmem_hex() trace/osnoise: Support hotplug operations trace/hwlat: Support hotplug operations trace/hwlat: Protect kdata->kthread with get/put_online_cpus trace: Add timerlat tracer trace: Add osnoise tracer ...
| * Documentation: Fix a typo on trace/osnoise-tracerDaniel Bristot de Oliveira2021-06-281-1/+1
| | | | | | | | | | | | | | | | | | | | s/RUNTIME IN USE/RUNTIME IN US/ Link: https://lkml.kernel.org/r/43e5160422a967218aa651c47f523e8d32d6a59e.1624872608.git.bristot@redhat.com Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * trace: Add timerlat tracerDaniel Bristot de Oliveira2021-06-252-0/+182
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The timerlat tracer aims to help the preemptive kernel developers to found souces of wakeup latencies of real-time threads. Like cyclictest, the tracer sets a periodic timer that wakes up a thread. The thread then computes a *wakeup latency* value as the difference between the *current time* and the *absolute time* that the timer was set to expire. The main goal of timerlat is tracing in such a way to help kernel developers. Usage Write the ASCII text "timerlat" into the current_tracer file of the tracing system (generally mounted at /sys/kernel/tracing). For example: [root@f32 ~]# cd /sys/kernel/tracing/ [root@f32 tracing]# echo timerlat > current_tracer It is possible to follow the trace by reading the trace trace file: [root@f32 tracing]# cat trace # tracer: timerlat # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # || / # |||| ACTIVATION # TASK-PID CPU# |||| TIMESTAMP ID CONTEXT LATENCY # | | | |||| | | | | <idle>-0 [000] d.h1 54.029328: #1 context irq timer_latency 932 ns <...>-867 [000] .... 54.029339: #1 context thread timer_latency 11700 ns <idle>-0 [001] dNh1 54.029346: #1 context irq timer_latency 2833 ns <...>-868 [001] .... 54.029353: #1 context thread timer_latency 9820 ns <idle>-0 [000] d.h1 54.030328: #2 context irq timer_latency 769 ns <...>-867 [000] .... 54.030330: #2 context thread timer_latency 3070 ns <idle>-0 [001] d.h1 54.030344: #2 context irq timer_latency 935 ns <...>-868 [001] .... 54.030347: #2 context thread timer_latency 4351 ns The tracer creates a per-cpu kernel thread with real-time priority that prints two lines at every activation. The first is the *timer latency* observed at the *hardirq* context before the activation of the thread. The second is the *timer latency* observed by the thread, which is the same level that cyclictest reports. The ACTIVATION ID field serves to relate the *irq* execution to its respective *thread* execution. The irq/thread splitting is important to clarify at which context the unexpected high value is coming from. The *irq* context can be delayed by hardware related actions, such as SMIs, NMIs, IRQs or by a thread masking interrupts. Once the timer happens, the delay can also be influenced by blocking caused by threads. For example, by postponing the scheduler execution via preempt_disable(), by the scheduler execution, or by masking interrupts. Threads can also be delayed by the interference from other threads and IRQs. The timerlat can also take advantage of the osnoise: traceevents. For example: [root@f32 ~]# cd /sys/kernel/tracing/ [root@f32 tracing]# echo timerlat > current_tracer [root@f32 tracing]# echo osnoise > set_event [root@f32 tracing]# echo 25 > osnoise/stop_tracing_total_us [root@f32 tracing]# tail -10 trace cc1-87882 [005] d..h... 548.771078: #402268 context irq timer_latency 1585 ns cc1-87882 [005] dNLh1.. 548.771082: irq_noise: local_timer:236 start 548.771077442 duration 4597 ns cc1-87882 [005] dNLh2.. 548.771083: irq_noise: reschedule:253 start 548.771083017 duration 56 ns cc1-87882 [005] dNLh2.. 548.771086: irq_noise: call_function_single:251 start 548.771083811 duration 2048 ns cc1-87882 [005] dNLh2.. 548.771088: irq_noise: call_function_single:251 start 548.771086814 duration 1495 ns cc1-87882 [005] dNLh2.. 548.771091: irq_noise: call_function_single:251 start 548.771089194 duration 1558 ns cc1-87882 [005] dNLh2.. 548.771094: irq_noise: call_function_single:251 start 548.771091719 duration 1932 ns cc1-87882 [005] dNLh2.. 548.771096: irq_noise: call_function_single:251 start 548.771094696 duration 1050 ns cc1-87882 [005] d...3.. 548.771101: thread_noise: cc1:87882 start 548.771078243 duration 10909 ns timerlat/5-1035 [005] ....... 548.771103: #402268 context thread timer_latency 25960 ns For further information see: Documentation/trace/timerlat-tracer.rst Link: https://lkml.kernel.org/r/71f18efc013e1194bcaea1e54db957de2b19ba62.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * trace: Add osnoise tracerDaniel Bristot de Oliveira2021-06-252-0/+153
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the context of high-performance computing (HPC), the Operating System Noise (*osnoise*) refers to the interference experienced by an application due to activities inside the operating system. In the context of Linux, NMIs, IRQs, SoftIRQs, and any other system thread can cause noise to the system. Moreover, hardware-related jobs can also cause noise, for example, via SMIs. The osnoise tracer leverages the hwlat_detector by running a similar loop with preemption, SoftIRQs and IRQs enabled, thus allowing all the sources of *osnoise* during its execution. Using the same approach of hwlat, osnoise takes note of the entry and exit point of any source of interferences, increasing a per-cpu interference counter. The osnoise tracer also saves an interference counter for each source of interference. The interference counter for NMI, IRQs, SoftIRQs, and threads is increased anytime the tool observes these interferences' entry events. When a noise happens without any interference from the operating system level, the hardware noise counter increases, pointing to a hardware-related noise. In this way, osnoise can account for any source of interference. At the end of the period, the osnoise tracer prints the sum of all noise, the max single noise, the percentage of CPU available for the thread, and the counters for the noise sources. Usage Write the ASCII text "osnoise" into the current_tracer file of the tracing system (generally mounted at /sys/kernel/tracing). For example:: [root@f32 ~]# cd /sys/kernel/tracing/ [root@f32 tracing]# echo osnoise > current_tracer It is possible to follow the trace by reading the trace trace file:: [root@f32 tracing]# cat trace # tracer: osnoise # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth MAX # || / SINGLE Interference counters: # |||| RUNTIME NOISE % OF CPU NOISE +-----------------------------+ # TASK-PID CPU# |||| TIMESTAMP IN US IN US AVAILABLE IN US HW NMI IRQ SIRQ THREAD # | | | |||| | | | | | | | | | | <...>-859 [000] .... 81.637220: 1000000 190 99.98100 9 18 0 1007 18 1 <...>-860 [001] .... 81.638154: 1000000 656 99.93440 74 23 0 1006 16 3 <...>-861 [002] .... 81.638193: 1000000 5675 99.43250 202 6 0 1013 25 21 <...>-862 [003] .... 81.638242: 1000000 125 99.98750 45 1 0 1011 23 0 <...>-863 [004] .... 81.638260: 1000000 1721 99.82790 168 7 0 1002 49 41 <...>-864 [005] .... 81.638286: 1000000 263 99.97370 57 6 0 1006 26 2 <...>-865 [006] .... 81.638302: 1000000 109 99.98910 21 3 0 1006 18 1 <...>-866 [007] .... 81.638326: 1000000 7816 99.21840 107 8 0 1016 39 19 In addition to the regular trace fields (from TASK-PID to TIMESTAMP), the tracer prints a message at the end of each period for each CPU that is running an osnoise/CPU thread. The osnoise specific fields report: - The RUNTIME IN USE reports the amount of time in microseconds that the osnoise thread kept looping reading the time. - The NOISE IN US reports the sum of noise in microseconds observed by the osnoise tracer during the associated runtime. - The % OF CPU AVAILABLE reports the percentage of CPU available for the osnoise thread during the runtime window. - The MAX SINGLE NOISE IN US reports the maximum single noise observed during the runtime window. - The Interference counters display how many each of the respective interference happened during the runtime window. Note that the example above shows a high number of HW noise samples. The reason being is that this sample was taken on a virtual machine, and the host interference is detected as a hardware interference. Tracer options The tracer has a set of options inside the osnoise directory, they are: - osnoise/cpus: CPUs at which a osnoise thread will execute. - osnoise/period_us: the period of the osnoise thread. - osnoise/runtime_us: how long an osnoise thread will look for noise. - osnoise/stop_tracing_us: stop the system tracing if a single noise higher than the configured value happens. Writing 0 disables this option. - osnoise/stop_tracing_total_us: stop the system tracing if total noise higher than the configured value happens. Writing 0 disables this option. - tracing_threshold: the minimum delta between two time() reads to be considered as noise, in us. When set to 0, the default value will be used, which is currently 5 us. Additional Tracing In addition to the tracer, a set of tracepoints were added to facilitate the identification of the osnoise source. - osnoise:sample_threshold: printed anytime a noise is higher than the configurable tolerance_ns. - osnoise:nmi_noise: noise from NMI, including the duration. - osnoise:irq_noise: noise from an IRQ, including the duration. - osnoise:softirq_noise: noise from a SoftIRQ, including the duration. - osnoise:thread_noise: noise from a thread, including the duration. Note that all the values are *net values*. For example, if while osnoise is running, another thread preempts the osnoise thread, it will start a thread_noise duration at the start. Then, an IRQ takes place, preempting the thread_noise, starting a irq_noise. When the IRQ ends its execution, it will compute its duration, and this duration will be subtracted from the thread_noise, in such a way as to avoid the double accounting of the IRQ execution. This logic is valid for all sources of noise. Here is one example of the usage of these tracepoints:: osnoise/8-961 [008] d.h. 5789.857532: irq_noise: local_timer:236 start 5789.857529929 duration 1845 ns osnoise/8-961 [008] dNh. 5789.858408: irq_noise: local_timer:236 start 5789.858404871 duration 2848 ns migration/8-54 [008] d... 5789.858413: thread_noise: migration/8:54 start 5789.858409300 duration 3068 ns osnoise/8-961 [008] .... 5789.858413: sample_threshold: start 5789.858404555 duration 8723 ns interferences 2 In this example, a noise sample of 8 microseconds was reported in the last line, pointing to two interferences. Looking backward in the trace, the two previous entries were about the migration thread running after a timer IRQ execution. The first event is not part of the noise because it took place one millisecond before. It is worth noticing that the sum of the duration reported in the tracepoints is smaller than eight us reported in the sample_threshold. The reason roots in the overhead of the entry and exit code that happens before and after any interference execution. This justifies the dual approach: measuring thread and tracing. Link: https://lkml.kernel.org/r/e649467042d60e7b62714c9c6751a56299d15119.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> [ Made the following functions static: trace_irqentry_callback() trace_irqexit_callback() trace_intel_irqentry_callback() trace_intel_irqexit_callback() Added to include/trace.h: osnoise_arch_register() osnoise_arch_unregister() Fixed define logic for LATENCY_FS_NOTIFY Reported-by: kernel test robot <lkp@intel.com> ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * trace/hwlat: Implement the per-cpu modeDaniel Bristot de Oliveira2021-06-251-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implements the per-cpu mode in which a sampling thread is created for each cpu in the "cpus" (and tracing_mask). The per-cpu mode has the potention to speed up the hwlat detection by running on multiple CPUs at the same time, at the cost of higher cpu usage with irqs disabled. Use with care. [ Changed get_cpu_data() to static. Reported-by: kernel test robot <lkp@intel.com> ] Link: https://lkml.kernel.org/r/ec06d0ab340e8460d293772faba19ad8a5c371aa.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * trace/hwlat: Implement the mode config optionDaniel Bristot de Oliveira2021-06-241-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provides the "mode" config to the hardware latency detector. hwlatd has two different operation modes. The default mode is the "round-robin" one, in which a single hwlatd thread runs, migrating among the allowed CPUs in a "round-robin" fashion. This is the current behavior. The "none" sets the allowed cpumask for a single hwlatd thread at the startup, but skips the round-robin, letting the scheduler handle the migration. In preparation to the per-cpu mode. Link: https://lkml.kernel.org/r/f3b1271262aa030c680e26615c1b9b2d71e55e92.1624372313.git.bristot@redhat.com Cc: Phil Auld <pauld@redhat.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Kate Carcia <kcarcia@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alexandre Chartre <alexandre.chartre@oracle.com> Cc: Clark Willaims <williams@redhat.com> Cc: John Kacur <jkacur@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * Documentation: tracing: Add per-group/all events enablement desciptionMasami Hiramatsu2021-06-101-0/+6
| | | | | | | | | | | | | | | | | | | | Add ftrace.event.<GROUP>.enable and ftrace.event.enable bootconfig description in the boot-time tracing document. Link: https://lkml.kernel.org/r/162264438901.302580.10697703336929432947.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | Merge tag 'docs-5.14' of git://git.lwn.net/linuxLinus Torvalds2021-06-283-7/+9
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull documentation updates from Jonathan Corbet: "This was a reasonably active cycle for documentation; this includes: - Some kernel-doc cleanups. That script is still regex onslaught from hell, but it has gotten a little better. - Improvements to the checkpatch docs, which are also used by the tool itself. - A major update to the pathname lookup documentation. - Elimination of :doc: markup, since our automarkup magic can create references from filenames without all the extra noise. - The flurry of Chinese translation activity continues. Plus, of course, the usual collection of updates, typo fixes, and warning fixes" * tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits) docs: path-lookup: use bare function() rather than literals docs: path-lookup: update symlink description docs: path-lookup: update get_link() ->follow_link description docs: path-lookup: update WALK_GET, WALK_PUT desc docs: path-lookup: no get_link() docs: path-lookup: update i_op->put_link and cookie description docs: path-lookup: i_op->follow_link replaced with i_op->get_link docs: path-lookup: Add macro name to symlink limit description docs: path-lookup: remove filename_mountpoint docs: path-lookup: update do_last() part docs: path-lookup: update path_mountpoint() part docs: path-lookup: update path_to_nameidata() part docs: path-lookup: update follow_managed() part docs: Makefile: Use CONFIG_SHELL not SHELL docs: Take a little noise out of the build process docs: x86: avoid using ReST :doc:`foo` markup docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup ...
| * | docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab2021-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/cf9b03ff4b7917d9846503f198372bc6b821445b.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| * | docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab2021-06-171-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/c79be625f7c90468e13d5380f0e4e1c1ccfa2fc8.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| * | docs: trace: coresight: coresight-etm4x-reference.rst: replace some charactersMauro Carvalho Chehab2021-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The conversion tools used during DocBook/LaTeX/html/Markdown->ReST conversion and some cut-and-pasted text contain some characters that aren't easily reachable on standard keyboards and/or could cause troubles when parsed by the documentation build system. Replace the occurences of the following characters: - U+00a0 (' '): NO-BREAK SPACE as it can cause lines being truncated on PDF output Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/b6a04e881bc80a3c1d3d23ccbc8208ca3c9053fd.1623826294.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
| * | docs: Fix typos in Documentation/trace/ftrace.rstHaocheng Xie2021-06-011-2/+2
| |/ | | | | | | | | | | | | | | | | Fix the usage of "a/the" and improve the readability. Signed-off-by: Haocheng Xie <xiehaocheng.cn@gmail.com> Link: https://lore.kernel.org/r/20210531083905.25763-1-xiehaocheng.cn@gmail.com [jc: tweaked wording slightly] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* / kprobes: Remove kprobe::fault_handlerPeter Zijlstra2021-06-011-19/+5
|/ | | | | | | | | | | | | | | | | | | The reason for kprobe::fault_handler(), as given by their comment: * We come here because instructions in the pre/post * handler caused the page_fault, this could happen * if handler tries to access user space by * copy_from_user(), get_user() etc. Let the * user-specified handler try to fix it first. Is just plain bad. Those other handlers are ran from non-preemptible context and had better use _nofault() functions. Also, there is no upstream usage of this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20210525073213.561116662@infradead.org
* Documentation: trace: Add documentation for TRBEAnshuman Khandual2021-04-061-0/+38
| | | | | | | | | | | | Add documentation for the TRBE under trace/coresight. Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> [ Split from the TRBE driver patch ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20210405164307.1720226-20-suzuki.poulose@arm.com Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
* Merge tag 'char-misc-5.12-rc1' of ↵Linus Torvalds2021-02-241-0/+32
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the large set of char/misc/whatever driver subsystem updates for 5.12-rc1. Over time it seems like this tree is collecting more and more tiny driver subsystems in one place, making it easier for those maintainers, which is why this is getting larger. Included in here are: - coresight driver updates - habannalabs driver updates - virtual acrn driver addition (proper acks from the x86 maintainers) - broadcom misc driver addition - speakup driver updates - soundwire driver updates - fpga driver updates - amba driver updates - mei driver updates - vfio driver updates - greybus driver updates - nvmeem driver updates - phy driver updates - mhi driver updates - interconnect driver udpates - fsl-mc bus driver updates - random driver fix - some small misc driver updates (rtsx, pvpanic, etc.) All of these have been in linux-next for a while, with the only reported issue being a merge conflict due to the dfl_device_id addition from the fpga subsystem in here" * tag 'char-misc-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (311 commits) spmi: spmi-pmic-arb: Fix hw_irq overflow Documentation: coresight: Add PID tracing description coresight: etm-perf: Support PID tracing for kernel at EL2 coresight: etm-perf: Clarify comment on perf options ACRN: update MAINTAINERS: mailing list is subscribers-only regmap: sdw-mbq: use MODULE_LICENSE("GPL") regmap: sdw: use no_pm routines for SoundWire 1.2 MBQ regmap: sdw: use _no_pm functions in regmap_read/write soundwire: intel: fix possible crash when no device is detected MAINTAINERS: replace my with email with replacements mhi: Fix double dma free uapi: map_to_7segment: Update example in documentation uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED drivers/misc/vmw_vmci: restrict too big queue size in qp_host_alloc_queue firewire: replace tricky statement by two simple ones vme: make remove callback return void firmware: google: make coreboot driver's remove callback return void firmware: xilinx: Use explicit values for all enum values sample/acrn: Introduce a sample of HSM ioctl interface usage virt: acrn: Introduce an interface for Service VM to control vCPU ...
| * Documentation: coresight: Add PID tracing descriptionLeo Yan2021-02-111-0/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After support the PID tracing for the kernel in EL1 or EL2, the usage gets more complicated. This patch gives description for the PMU formats of contextID configs, this can help users to understand how to control the knobs for PID tracing when the kernel is in different ELs. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Mike Leach <mike.leach@linaro.org> Signed-off-by: Leo Yan <leo.yan@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20210206150833.42120-9-leo.yan@linaro.org Link: https://lore.kernel.org/r/20210211172038.2483517-4-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tracing: Add ptr-hash option to show the hashed pointer valueMasami Hiramatsu2021-02-111-0/+6
|/ | | | | | | | | | | | | | | | | | Add tracefs/options/hash-ptr option to show hashed pointer value by %p in event printk format string. For the security reason, normal printk will show the hashed pointer value (encrypted by random number) with %p to printk buffer to hide the real address. But the tracefs/trace always shows real address for debug. To bridge those outputs, add an option to switch the output format. Ftrace users can use it to find the hashed value corresponding to the real address in trace log. Link: https://lkml.kernel.org/r/160277372504.29307.14909828808982012211.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>