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2019-12-04Merge tag 'trace-v5.5-2' of ↵Linus Torvalds7-0/+371
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: "Two fixes and one patch that was missed: Fixes: - Missing __print_hex_dump undef for processing new function in trace events - Stop WARN_ON messages when lockdown disables tracing on boot up Enhancement: - Debug option to inject trace events from userspace (for rasdaemon)" The enhancement has its own config option and is non invasive. It's been discussed for sever months and should have been added to my original push, but I never pulled it into my queue. * tag 'trace-v5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Do not create directories if lockdown is in affect tracing: Introduce trace event injection tracing: Fix __print_hex_dump scope
2019-12-04tracing: Do not create directories if lockdown is in affectSteven Rostedt (VMware)2-0/+23
If lockdown is disabling tracing on boot up, it prevents the tracing files from even bering created. But when that happens, there's several places that will give a warning that the files were not created as that is usually a sign of a bug. Add in strategic locations where a check is made to see if tracing is disabled by lockdown, and if it is, do not go further, and fail silently (but print that tracing is disabled by lockdown, without doing a WARN_ON()). Cc: Matthew Garrett <mjg59@google.com> Fixes: 17911ff38aa5 ("tracing: Add locked_down checks to the open calls of files created for tracefs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-12-03Merge branch 'irq-core-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Ingo Molnar: "Most of the IRQ subsystem changes in this cycle were irq-chip driver updates: - Qualcomm PDC wakeup interrupt support - Layerscape external IRQ support - Broadcom bcm7038 PM and wakeup support - Ingenic driver cleanup and modernization - GICv3 ITS preparation for GICv4.1 updates - GICv4 fixes There's also the series from Frederic Weisbecker that fixes memory ordering bugs for the irq-work logic, whose primary fix is to turn work->irq_work.flags into an atomic variable and then convert the complex (and buggy) atomic_cmpxchg() loop in irq_work_claim() into a much simpler atomic_fetch_or() call. There are also various smaller cleanups" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) pinctrl/sdm845: Add PDC wakeup interrupt map for GPIOs pinctrl/msm: Setup GPIO chip in hierarchy irqchip/qcom-pdc: Add irqchip set/get state calls irqchip/qcom-pdc: Add irqdomain for wakeup capable GPIOs irqchip/qcom-pdc: Do not toggle IRQ_ENABLE during mask/unmask irqchip/qcom-pdc: Update max PDC interrupts of/irq: Document properties for wakeup interrupt parent genirq: Introduce irq_chip_get/set_parent_state calls irqdomain: Add bus token DOMAIN_BUS_WAKEUP genirq: Fix function documentation of __irq_alloc_descs() irq_work: Fix IRQ_WORK_BUSY bit clearing irqchip/ti-sci-inta: Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...)) irq_work: Slightly simplify IRQ_WORK_PENDING clearing irq_work: Fix irq_work_claim() memory ordering irq_work: Convert flags to atomic_t irqchip: Ingenic: Add process for more than one irq at the same time. irqchip: ingenic: Alloc generic chips from IRQ domain irqchip: ingenic: Get virq number from IRQ domain irqchip: ingenic: Error out if IRQ domain creation failed irqchip: ingenic: Drop redundant irq_suspend / irq_resume functions ...
2019-12-02tracing: Introduce trace event injectionCong Wang5-0/+348
We have been trying to use rasdaemon to monitor hardware errors like correctable memory errors. rasdaemon uses trace events to monitor various hardware errors. In order to test it, we have to inject some hardware errors, unfortunately not all of them provide error injections. MCE does provide a way to inject MCE errors, but errors like PCI error and devlink error don't, it is not easy to add error injection to each of them. Instead, it is relatively easier to just allow users to inject trace events in a generic way so that all trace events can be injected. This patch introduces trace event injection, where a new 'inject' is added to each tracepoint directory. Users could write into this file with key=value pairs to specify the value of each fields of the trace event, all unspecified fields are set to zero values by default. For example, for the net/net_dev_queue tracepoint, we can inject: INJECT=/sys/kernel/debug/tracing/events/net/net_dev_queue/inject echo "" > $INJECT echo "name='test'" > $INJECT echo "name='test' len=1024" > $INJECT cat /sys/kernel/debug/tracing/trace ... <...>-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0 <...>-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0 <...>-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024 Triggers could be triggered as usual too: echo "stacktrace if len == 1025" > /sys/kernel/debug/tracing/events/net/net_dev_queue/trigger echo "len=1025" > $INJECT cat /sys/kernel/debug/tracing/trace ... bash-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0 bash-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0 bash-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024 bash-614 [001] .N.1 284.236349: <stack trace> => event_inject_write => vfs_write => ksys_write => do_syscall_64 => entry_SYSCALL_64_after_hwframe The only thing that can't be injected is string pointers as they require constant string pointers, this can't be done at run time. Link: http://lkml.kernel.org/r/20191130045218.18979-1-xiyou.wangcong@gmail.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-27Merge tag 'trace-v5.5' of ↵Linus Torvalds18-143/+1064
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New tracing features: - New PERMANENT flag to ftrace_ops when attaching a callback to a function. As /proc/sys/kernel/ftrace_enabled when set to zero will disable all attached callbacks in ftrace, this has a detrimental impact on live kernel tracing, as it disables all that it patched. If a ftrace_ops is registered to ftrace with the PERMANENT flag set, it will prevent ftrace_enabled from being disabled, and if ftrace_enabled is already disabled, it will prevent a ftrace_ops with PREMANENT flag set from being registered. - New register_ftrace_direct(). As eBPF would like to register its own trampolines to be called by the ftrace nop locations directly, without going through the ftrace trampoline, this function has been added. This allows for eBPF trampolines to live along side of ftrace, perf, kprobe and live patching. It also utilizes the ftrace enabled_functions file that keeps track of functions that have been modified in the kernel, to allow for security auditing. - Allow for kernel internal use of ftrace instances. Subsystems in the kernel can now create and destroy their own tracing instances which allows them to have their own tracing buffer, and be able to record events without worrying about other users from writing over their data. - New seq_buf_hex_dump() that lets users use the hex_dump() in their seq_buf usage. - Notifications now added to tracing_max_latency to allow user space to know when a new max latency is hit by one of the latency tracers. - Wider spread use of generic compare operations for use of bsearch and friends. - More synthetic event fields may be defined (32 up from 16) - Use of xarray for architectures with sparse system calls, for the system call trace events. This along with small clean ups and fixes" * tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (51 commits) tracing: Enable syscall optimization for MIPS tracing: Use xarray for syscall trace events tracing: Sample module to demonstrate kernel access to Ftrace instances. tracing: Adding new functions for kernel access to Ftrace instances tracing: Fix Kconfig indentation ring-buffer: Fix typos in function ring_buffer_producer ftrace: Use BIT() macro ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured ftrace: Rename ftrace_graph_stub to ftrace_stub_graph ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization ftrace: Add helper find_direct_entry() to consolidate code ftrace: Add another check for match in register_ftrace_direct() ftrace: Fix accounting bug with direct->count in register_ftrace_direct() ftrace/selftests: Fix spelling mistake "wakeing" -> "waking" tracing: Increase SYNTH_FIELDS_MAX for synthetic_events ftrace/samples: Add a sample module that implements modify_ftrace_direct() ftrace: Add modify_ftrace_direct() tracing: Add missing "inline" in stub function of latency_fsnotify() tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text tracing: Use seq_buf_hex_dump() to dump buffers ...
2019-11-27Merge tag 'driver-core-5.5-rc1' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the "big" set of driver core patches for 5.5-rc1 There's a few minor cleanups and fixes in here, but the majority of the patches in here fall into two buckets: - debugfs api cleanups and fixes - driver core device link support for boot dependancy issues The debugfs api cleanups are working to slowly refactor the debugfs apis so that it is even harder to use incorrectly. That work has been happening for the past few kernel releases and will continue over time, it's a long-term project/goal The driver core device link support missed 5.4 by just a bit, so it's been sitting and baking for many months now. It's from Saravana Kannan to help resolve the problems that DT-based systems have at boot time with dependancy graphs and kernel modules. Turns out that no one has actually tried to build a generic arm64 kernel with loads of modules and have it "just work" for a variety of platforms (like a distro kernel). The big problem turned out to be a lack of dependency information between different areas of DT entries, and the work here resolves that problem and now allows devices to boot properly, and quicker than a monolith kernel. All of these patches have been in linux-next for a long time with no reported issues" * tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits) tracing: Remove unnecessary DEBUG_FS dependency of: property: Add device link support for interrupt-parent, dmas and -gpio(s) debugfs: Fix !DEBUG_FS debugfs_create_automount of: property: Add device link support for "iommu-map" of: property: Fix the semantics of of_is_ancestor_of() i2c: of: Populate fwnode in of_i2c_get_board_info() drivers: base: Fix Kconfig indentation firmware_loader: Fix labels with comma for builtin firmware driver core: Allow device link operations inside sync_state() driver core: platform: Declare ret variable only once cpu-topology: declare parse_acpi_topology in <linux/arch_topology.h> crypto: hisilicon: no need to check return value of debugfs_create functions driver core: platform: use the correct callback type for bus_find_device firmware_class: make firmware caching configurable driver core: Clarify documentation for fwnode_operations.add_links() mailbox: tegra: Fix superfluous IRQ error message net: caif: Fix debugfs on 64-bit platforms mac80211: Use debugfs_create_xul() helper media: c8sectpfe: no need to check return value of debugfs_create functions of: property: Add device link support for iommus, mboxes and io-channels ...
2019-11-26Merge branch 'perf-core-for-linus' of ↵Linus Torvalds1-5/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "The main kernel side changes in this cycle were: - Various Intel-PT updates and optimizations (Alexander Shishkin) - Prohibit kprobes on Xen/KVM emulate prefixes (Masami Hiramatsu) - Add support for LSM and SELinux checks to control access to the perf syscall (Joel Fernandes) - Misc other changes, optimizations, fixes and cleanups - see the shortlog for details. There were numerous tooling changes as well - 254 non-merge commits. Here are the main changes - too many to list in detail: - Enhancements to core tooling infrastructure, perf.data, libperf, libtraceevent, event parsing, vendor events, Intel PT, callchains, BPF support and instruction decoding. - There were updates to the following tools: perf annotate perf diff perf inject perf kvm perf list perf maps perf parse perf probe perf record perf report perf script perf stat perf test perf trace - And a lot of other changes: please see the shortlog and Git log for more details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (279 commits) perf parse: Fix potential memory leak when handling tracepoint errors perf probe: Fix spelling mistake "addrees" -> "address" libtraceevent: Fix memory leakage in copy_filter_type libtraceevent: Fix header installation perf intel-bts: Does not support AUX area sampling perf intel-pt: Add support for decoding AUX area samples perf intel-pt: Add support for recording AUX area samples perf pmu: When using default config, record which bits of config were changed by the user perf auxtrace: Add support for queuing AUX area samples perf session: Add facility to peek at all events perf auxtrace: Add support for dumping AUX area samples perf inject: Cut AUX area samples perf record: Add aux-sample-size config term perf record: Add support for AUX area sampling perf auxtrace: Add support for AUX area sample recording perf auxtrace: Move perf_evsel__find_pmu() perf record: Add a function to test for kernel support for AUX area sampling perf tools: Add kernel AUX area sampling definitions perf/core: Make the mlock accounting simple again perf report: Jump to symbol source view from total cycles view ...
2019-11-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-52/+175
Pull networking updates from David Miller: "Another merge window, another pull full of stuff: 1) Support alternative names for network devices, from Jiri Pirko. 2) Introduce per-netns netdev notifiers, also from Jiri Pirko. 3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara Larsen. 4) Allow compiling out the TLS TOE code, from Jakub Kicinski. 5) Add several new tracepoints to the kTLS code, also from Jakub. 6) Support set channels ethtool callback in ena driver, from Sameeh Jubran. 7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED, SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long. 8) Add XDP support to mvneta driver, from Lorenzo Bianconi. 9) Lots of netfilter hw offload fixes, cleanups and enhancements, from Pablo Neira Ayuso. 10) PTP support for aquantia chips, from Egor Pomozov. 11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From Josh Hunt. 12) Add smart nagle to tipc, from Jon Maloy. 13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat Duvvuru. 14) Add a flow mask cache to OVS, from Tonghao Zhang. 15) Add XDP support to ice driver, from Maciej Fijalkowski. 16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak. 17) Support UDP GSO offload in atlantic driver, from Igor Russkikh. 18) Support it in stmmac driver too, from Jose Abreu. 19) Support TIPC encryption and auth, from Tuong Lien. 20) Introduce BPF trampolines, from Alexei Starovoitov. 21) Make page_pool API more numa friendly, from Saeed Mahameed. 22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni. 23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits) libbpf: Fix usage of u32 in userspace code mm: Implement no-MMU variant of vmalloc_user_node_flags slip: Fix use-after-free Read in slip_open net: dsa: sja1105: fix sja1105_parse_rgmii_delays() macvlan: schedule bc_work even if error enetc: add support Credit Based Shaper(CBS) for hardware offload net: phy: add helpers phy_(un)lock_mdio_bus mdio_bus: don't use managed reset-controller ax88179_178a: add ethtool_op_get_ts_info() mlxsw: spectrum_router: Fix use of uninitialized adjacency index mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels bpf: Simplify __bpf_arch_text_poke poke type handling bpf: Introduce BPF_TRACE_x helper for the tracing tests bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT bpf, testing: Add various tail call test cases bpf, x86: Emit patchable direct jump as tail call bpf: Constant map key tracking for prog array pokes bpf: Add poke dependency tracking for prog array maps bpf: Add initial poke descriptor table for jit images bpf: Move owner type, jited info into array auxiliary data ...
2019-11-25Merge tag 'printk-for-5.5' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk updates from Petr Mladek: - Allow to print symbolic error names via new %pe modifier. - Use pr_warn() instead of the remaining pr_warning() calls. Fix formatting of the related lines. - Add VSPRINTF entry to MAINTAINERS. * tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits) checkpatch: don't warn about new vsprintf pointer extension '%pe' MAINTAINERS: Add VSPRINTF tools lib api: Renaming pr_warning to pr_warn ASoC: samsung: Use pr_warn instead of pr_warning lib: cpu_rmap: Use pr_warn instead of pr_warning trace: Use pr_warn instead of pr_warning dma-debug: Use pr_warn instead of pr_warning vgacon: Use pr_warn instead of pr_warning fs: afs: Use pr_warn instead of pr_warning sh/intc: Use pr_warn instead of pr_warning scsi: Use pr_warn instead of pr_warning platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning platform/x86: asus-laptop: Use pr_warn instead of pr_warning platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning oprofile: Use pr_warn instead of pr_warning of: Use pr_warn instead of pr_warning macintosh: Use pr_warn instead of pr_warning idsn: Use pr_warn instead of pr_warning ide: Use pr_warn instead of pr_warning crypto: n2: Use pr_warn instead of pr_warning ...
2019-11-25Merge branch 'for-5.5' of ↵Linus Torvalds1-38/+46
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "There are several notable changes here: - Single thread migrating itself has been optimized so that it doesn't need threadgroup rwsem anymore. - Freezer optimization to avoid unnecessary frozen state changes. - cgroup ID unification so that cgroup fs ino is the only unique ID used for the cgroup and can be used to directly look up live cgroups through filehandle interface on 64bit ino archs. On 32bit archs, cgroup fs ino is still the only ID in use but it is only unique when combined with gen. - selftest and other changes" * 'for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (24 commits) writeback: fix -Wformat compilation warnings docs: cgroup: mm: Fix spelling of "list" cgroup: fix incorrect WARN_ON_ONCE() in cgroup_setup_root() cgroup: use cgrp->kn->id as the cgroup ID kernfs: use 64bit inos if ino_t is 64bit kernfs: implement custom exportfs ops and fid type kernfs: combine ino/id lookup functions into kernfs_find_and_get_node_by_id() kernfs: convert kernfs_node->id from union kernfs_node_id to u64 kernfs: kernfs_find_and_get_node_by_ino() should only look up activated nodes kernfs: use dumber locking for kernfs_find_and_get_node_by_ino() netprio: use css ID instead of cgroup ID writeback: use ino_t for inodes in tracepoints kernfs: fix ino wrap-around detection kselftests: cgroup: Avoid the reuse of fd after it is deallocated cgroup: freezer: don't change task and cgroups status unnecessarily cgroup: use cgroup->last_bstat instead of cgroup->bstat_pending for consistency cgroup: remove cgroup_enable_task_cg_lists() optimization cgroup: pids: use atomic64_t for pids->limit selftests: cgroup: Run test_core under interfering stress selftests: cgroup: Add task migration tests ...
2019-11-25Merge tag 'arm64-upstream' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Apart from the arm64-specific bits (core arch and perf, new arm64 selftests), it touches the generic cow_user_page() (reviewed by Kirill) together with a macro for x86 to preserve the existing behaviour on this architecture. Summary: - On ARMv8 CPUs without hardware updates of the access flag, avoid failing cow_user_page() on PFN mappings if the pte is old. The patches introduce an arch_faults_on_old_pte() macro, defined as false on x86. When true, cow_user_page() makes the pte young before attempting __copy_from_user_inatomic(). - Covert the synchronous exception handling paths in arch/arm64/kernel/entry.S to C. - FTRACE_WITH_REGS support for arm64. - ZONE_DMA re-introduced on arm64 to support Raspberry Pi 4 - Several kselftest cases specific to arm64, together with a MAINTAINERS update for these files (moved to the ARM64 PORT entry). - Workaround for a Neoverse-N1 erratum where the CPU may fetch stale instructions under certain conditions. - Workaround for Cortex-A57 and A72 errata where the CPU may speculatively execute an AT instruction and associate a VMID with the wrong guest page tables (corrupting the TLB). - Perf updates for arm64: additional PMU topologies on HiSilicon platforms, support for CCN-512 interconnect, AXI ID filtering in the IMX8 DDR PMU, support for the CCPI2 uncore PMU in ThunderX2. - GICv3 optimisation to avoid a heavy barrier when accessing the ICC_PMR_EL1 register. - ELF HWCAP documentation updates and clean-up. - SMC calling convention conduit code clean-up. - KASLR diagnostics printed during boot - NVIDIA Carmel CPU added to the KPTI whitelist - Some arm64 mm clean-ups: use generic free_initrd_mem(), remove stale macro, simplify calculation in __create_pgd_mapping(), typos. - Kconfig clean-ups: CMDLINE_FORCE to depend on CMDLINE, choice for endinanness to help with allmodconfig" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits) arm64: Kconfig: add a choice for endianness kselftest: arm64: fix spelling mistake "contiguos" -> "contiguous" arm64: Kconfig: make CMDLINE_FORCE depend on CMDLINE MAINTAINERS: Add arm64 selftests to the ARM64 PORT entry arm64: kaslr: Check command line before looking for a seed arm64: kaslr: Announce KASLR status on boot kselftest: arm64: fake_sigreturn_misaligned_sp kselftest: arm64: fake_sigreturn_bad_size kselftest: arm64: fake_sigreturn_duplicated_fpsimd kselftest: arm64: fake_sigreturn_missing_fpsimd kselftest: arm64: fake_sigreturn_bad_size_for_magic0 kselftest: arm64: fake_sigreturn_bad_magic kselftest: arm64: add helper get_current_context kselftest: arm64: extend test_init functionalities kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht] kselftest: arm64: mangle_pstate_invalid_daif_bits kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils kselftest: arm64: extend toplevel skeleton Makefile drivers/perf: hisi: update the sccl_id/ccl_id for certain HiSilicon platform arm64: mm: reserve CMA and crashkernel in ZONE_DMA32 ...
2019-11-22tracing: Use xarray for syscall trace eventsHassan Naveed1-7/+25
Currently, a lot of memory is wasted for architectures like MIPS when init_ftrace_syscalls() allocates the array for syscalls using kcalloc. This is because syscalls numbers start from 4000, 5000 or 6000 and array elements up to that point are unused. Fix this by using a data structure more suited to storing sparsely populated arrays. The XARRAY data structure, implemented using radix trees, is much more memory efficient for storing the syscalls in question. Link: http://lkml.kernel.org/r/20191115234314.21599-1-hnaveed@wavecomp.com Signed-off-by: Hassan Naveed <hnaveed@wavecomp.com> Reviewed-by: Paul Burton <paulburton@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-22tracing: Adding new functions for kernel access to Ftrace instancesDivya Indi3-22/+102
Adding 2 new functions - 1) struct trace_array *trace_array_get_by_name(const char *name); Return pointer to a trace array with given name. If it does not exist, create and return pointer to the new trace array. 2) int trace_array_set_clr_event(struct trace_array *tr, const char *system ,const char *event, bool enable); Enable/Disable events to this trace array. Additionally, - To handle reference counters, export trace_array_put() - Due to introduction of the above 2 new functions, we no longer need to export - ftrace_set_clr_event & trace_array_create APIs. Link: http://lkml.kernel.org/r/1574276919-11119-2-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-22tracing: Fix Kconfig indentationKrzysztof Kozlowski1-4/+4
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Link: http://lkml.kernel.org/r/20191120133807.12741-1-krzk@kernel.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-22ring-buffer: Fix typos in function ring_buffer_producerXianting Tian1-2/+2
Fix spelling and other typos Link: http://lkml.kernel.org/r/1573916755-32478-1-git-send-email-xianting_tian@126.com Signed-off-by: Xianting Tian <xianting_tian@126.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-22tracing: Remove unnecessary DEBUG_FS dependencyKusanagi Kouichi1-1/+0
Tracing replaced debugfs with tracefs. Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20191120104350753.EWCT.12796.ppp.dion.ne.jp@dmta0009.auone-net.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-18ftrace: Rename ftrace_graph_stub to ftrace_stub_graphSteven Rostedt (VMware)1-3/+3
The ftrace_graph_stub was created and points to ftrace_stub as a way to assign the functon graph tracer function pointer to a stub function with a different prototype than what ftrace_stub has and not trigger the C verifier. The ftrace_graph_stub was created via the linker script vmlinux.lds.h. Unfortunately, powerpc already uses the name ftrace_graph_stub for its internal implementation of the function graph tracer, and even though powerpc would still build, the change via the linker script broke function tracer on powerpc from working. By using the name ftrace_stub_graph, which does not exist anywhere else in the kernel, this should not be a problem. Link: https://lore.kernel.org/r/1573849732.5937.136.camel@lca.pw Fixes: b83b43ffc6e4 ("fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub") Reorted-by: Qian Cai <cai@lca.pw> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18ftrace: Add a helper function to modify_ftrace_direct() to allow arch ↵Steven Rostedt (VMware)1-32/+88
optimization If a direct ftrace callback is at a location that does not have any other ftrace helpers attached to it, it is possible to simply just change the text to call the new caller (if the architecture supports it). But this requires special architecture code. Currently, modify_ftrace_direct() uses a trick to add a stub ftrace callback to the location forcing it to call the ftrace iterator. Then it can change the direct helper to call the new function in C, and then remove the stub. Removing the stub will have the location now call the new location that the direct helper is using. The new helper function does the registering the stub trick, but is a weak function, allowing an architecture to override it to do something a bit more direct. Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add helper find_direct_entry() to consolidate codeSteven Rostedt (VMware)1-30/+29
Both unregister_ftrace_direct() and modify_ftrace_direct() needs to normalize the ip passed in to match the rec->ip, as it is acceptable to have the ip on the ftrace call site but not the start. There are also common validity checks with the record found by the ip, these should be done for both unregister_ftrace_direct() and modify_ftrace_direct(). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add another check for match in register_ftrace_direct()Steven Rostedt (VMware)1-1/+6
As an instruction pointer passed into register_ftrace_direct() may just exist on the ftrace call site, but may not be the start of the call site itself, register_ftrace_direct() still needs to update test if a direct call exists on the normalized site, as only one direct call is allowed at any one time. Fixes: 763e34e74bb7d ("ftrace: Add register_ftrace_direct()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Fix accounting bug with direct->count in register_ftrace_direct()Steven Rostedt (VMware)1-2/+1
The direct->count wasn't being updated properly, where it only was updated when the first entry was added, but should be updated every time. Fixes: 013bf0da04748 ("ftrace: Add ftrace_find_direct_func()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15tracing: Increase SYNTH_FIELDS_MAX for synthetic_eventsArtem Bityutskiy1-1/+1
Increase the maximum allowed count of synthetic event fields from 16 to 32 in order to allow for larger-than-usual events. Link: http://lkml.kernel.org/r/20191115091730.9192-1-dedekind1@gmail.com Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14ftrace: Add modify_ftrace_direct()Steven Rostedt (VMware)1-0/+78
Add a new function modify_ftrace_direct() that will allow a user to update an existing direct caller to a new trampoline, without missing hits due to unregistering one and then adding another. Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Add missing "inline" in stub function of latency_fsnotify()Steven Rostedt (VMware)1-1/+1
The latency_fsnotify() stub when the function is not defined, was missing the "inline". Link: https://lore.kernel.org/r/20191115140213.74c5efe7@canb.auug.org.au Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help textBorislav Petkov1-2/+2
There was a stray tab in the help text of the aforementioned config option which showed like this: The "print fmt" of the trace events will show the enum/sizeof names instead of their values. This can cause problems for user space tools ... in menuconfig. Remove it and end a sentence with a fullstop. No functional changes. Link: http://lkml.kernel.org/r/20191112174219.10933-1-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Use seq_buf_hex_dump() to dump buffersPiotr Maziarz2-0/+45
Without this, buffers can be printed with __print_array macro that has no formatting options and can be hard to read. The other way is to mimic formatting capability with multiple calls of trace event with one call per row which gives performance impact and different timestamp in each row. Link: http://lkml.kernel.org/r/1573130738-29390-2-git-send-email-piotrx.maziarz@linux.intel.com Signed-off-by: Piotr Maziarz <piotrx.maziarz@linux.intel.com> Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing/kprobe: Check whether the non-suffixed symbol is notraceMasami Hiramatsu1-3/+24
Check whether the non-suffixed symbol is notrace, since suffixed symbols are generated by the compilers for optimization. Based on these suffixed symbols, notrace check might not work because some of them are just a partial code of the original function. (e.g. cold-cache (unlikely) code is separated from original function as FUNCTION.cold.XX) For example, without this fix, # echo p device_add.cold.67 > /sys/kernel/debug/tracing/kprobe_events sh: write error: Invalid argument # cat /sys/kernel/debug/tracing/error_log [ 135.491035] trace_kprobe: error: Failed to register probe event Command: p device_add.cold.67 ^ # dmesg | tail -n 1 [ 135.488599] trace_kprobe: Could not probe notrace function device_add.cold.67 With this, # echo p device_add.cold.66 > /sys/kernel/debug/tracing/kprobe_events # cat /sys/kernel/debug/kprobes/list ffffffff81599de9 k device_add.cold.66+0x0 [DISABLED] Actually, kprobe blacklist already did similar thing, see within_kprobe_blacklist(). Link: http://lkml.kernel.org/r/157233790394.6706.18243942030937189679.stgit@devnote2 Fixes: 45408c4f9250 ("tracing: kprobes: Prohibit probing on notrace function") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: use kvcalloc for tgid_map array allocationYuming Han1-1/+1
Fail to allocate memory for tgid_map, because it requires order-6 page. detail as: c3 sh: page allocation failure: order:6, mode:0x140c0c0(GFP_KERNEL), nodemask=(null) c3 sh cpuset=/ mems_allowed=0 c3 CPU: 3 PID: 5632 Comm: sh Tainted: G W O 4.14.133+ #10 c3 Hardware name: Generic DT based system c3 Backtrace: c3 [<c010bdbc>] (dump_backtrace) from [<c010c08c>](show_stack+0x18/0x1c) c3 [<c010c074>] (show_stack) from [<c0993c54>](dump_stack+0x84/0xa4) c3 [<c0993bd0>] (dump_stack) from [<c0229858>](warn_alloc+0xc4/0x19c) c3 [<c0229798>] (warn_alloc) from [<c022a6e4>](__alloc_pages_nodemask+0xd18/0xf28) c3 [<c02299cc>] (__alloc_pages_nodemask) from [<c0248344>](kmalloc_order+0x20/0x38) c3 [<c0248324>] (kmalloc_order) from [<c0248380>](kmalloc_order_trace+0x24/0x108) c3 [<c024835c>] (kmalloc_order_trace) from [<c01e6078>](set_tracer_flag+0xb0/0x158) c3 [<c01e5fc8>] (set_tracer_flag) from [<c01e6404>](trace_options_core_write+0x7c/0xcc) c3 [<c01e6388>] (trace_options_core_write) from [<c0278b1c>](__vfs_write+0x40/0x14c) c3 [<c0278adc>] (__vfs_write) from [<c0278e10>](vfs_write+0xc4/0x198) c3 [<c0278d4c>] (vfs_write) from [<c027906c>](SyS_write+0x6c/0xd0) c3 [<c0279000>] (SyS_write) from [<c01079a0>](ret_fast_syscall+0x0/0x54) Switch to use kvcalloc to avoid unexpected allocation failures. Link: http://lkml.kernel.org/r/1571888070-24425-1-git-send-email-chunyan.zhang@unisoc.com Signed-off-by: Yuming Han <yuming.han@unisoc.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing/hwlat: Fix a few trivial nitsSrivatsa S. Bhat (VMware)1-2/+2
Update the source file name in the comments, and fix a grammatical error. Link: http://lkml.kernel.org/r/157073346821.17189.8946944856026592247.stgit@srivatsa-ubuntu Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Use generic type for comparator functionAndy Shevchenko4-15/+13
Comparator function type, cmp_func_t, is defined in the types.h, use it in the code. Link: http://lkml.kernel.org/r/20191007135656.37734-3-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stubSteven Rostedt (VMware)1-3/+8
The C compiler is allowing more checks to make sure that function pointers are assigned to the correct prototype function. Unfortunately, the function graph tracer uses a special name with its assigned ftrace_graph_return function pointer that maps to a stub function used by the function tracer (ftrace_stub). The ftrace_graph_return variable is compared to the ftrace_stub in some archs to know if the function graph tracer is enabled or not. This means we can not just simply create a new function stub that compares it without modifying all the archs. Instead, have the linker script create a function_graph_stub that maps to ftrace_stub, and this way we can define the prototype for it to match the prototype of ftrace_graph_return, and make the compiler checks all happy! Link: http://lkml.kernel.org/r/20191015090055.789a0aed@gandalf.local.home Cc: linux-sh@vger.kernel.org Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Reported-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Adding NULL checks for trace_array descriptor pointerDivya Indi2-0/+5
As part of commit f45d1225adb0 ("tracing: Kernel access to Ftrace instances") we exported certain functions. Here, we are adding some additional NULL checks to ensure safe usage by users of these APIs. Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Verify if trace array exists before destroying it.Divya Indi1-3/+12
A trace array can be destroyed from userspace or kernel. Verify if the trace array exists before proceeding to destroy/remove it. Link: http://lkml.kernel.org/r/1565805327-579-3-git-send-email-divya.indi@oracle.com Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com> Signed-off-by: Divya Indi <divya.indi@oracle.com> [ Removed unneeded braces ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Declare newly exported APIs in include/linux/trace.hDivya Indi1-3/+1
Declare the newly introduced and exported APIs in the header file - include/linux/trace.h. Moving previous declarations from kernel/trace/trace.h to include/linux/trace.h. Link: http://lkml.kernel.org/r/1565805327-579-2-git-send-email-divya.indi@oracle.com Signed-off-by: Divya Indi <divya.indi@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Make internal ftrace events staticBen Dooks1-2/+2
The event_class_ftrace_##call and event_##call do not seem to be used outside of trace_export.c so make them both static to avoid a number of sparse warnings: kernel/trace/trace_entries.h:59:1: warning: symbol 'event_class_ftrace_function' was not declared. Should it be static? kernel/trace/trace_entries.h:59:1: warning: symbol '__event_function' was not declared. Should it be static? kernel/trace/trace_entries.h:77:1: warning: symbol 'event_class_ftrace_funcgraph_entry' was not declared. Should it be static? kernel/trace/trace_entries.h:77:1: warning: symbol '__event_funcgraph_entry' was not declared. Should it be static? kernel/trace/trace_entries.h:93:1: warning: symbol 'event_class_ftrace_funcgraph_exit' was not declared. Should it be static? kernel/trace/trace_entries.h:93:1: warning: symbol '__event_funcgraph_exit' was not declared. Should it be static? kernel/trace/trace_entries.h:129:1: warning: symbol 'event_class_ftrace_context_switch' was not declared. Should it be static? kernel/trace/trace_entries.h:129:1: warning: symbol '__event_context_switch' was not declared. Should it be static? kernel/trace/trace_entries.h:149:1: warning: symbol 'event_class_ftrace_wakeup' was not declared. Should it be static? kernel/trace/trace_entries.h:149:1: warning: symbol '__event_wakeup' was not declared. Should it be static? kernel/trace/trace_entries.h:171:1: warning: symbol 'event_class_ftrace_kernel_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:171:1: warning: symbol '__event_kernel_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:191:1: warning: symbol 'event_class_ftrace_user_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:191:1: warning: symbol '__event_user_stack' was not declared. Should it be static? kernel/trace/trace_entries.h:214:1: warning: symbol 'event_class_ftrace_bprint' was not declared. Should it be static? kernel/trace/trace_entries.h:214:1: warning: symbol '__event_bprint' was not declared. Should it be static? kernel/trace/trace_entries.h:230:1: warning: symbol 'event_class_ftrace_print' was not declared. Should it be static? kernel/trace/trace_entries.h:230:1: warning: symbol '__event_print' was not declared. Should it be static? kernel/trace/trace_entries.h:247:1: warning: symbol 'event_class_ftrace_raw_data' was not declared. Should it be static? kernel/trace/trace_entries.h:247:1: warning: symbol '__event_raw_data' was not declared. Should it be static? kernel/trace/trace_entries.h:262:1: warning: symbol 'event_class_ftrace_bputs' was not declared. Should it be static? kernel/trace/trace_entries.h:262:1: warning: symbol '__event_bputs' was not declared. Should it be static? kernel/trace/trace_entries.h:277:1: warning: symbol 'event_class_ftrace_mmiotrace_rw' was not declared. Should it be static? kernel/trace/trace_entries.h:277:1: warning: symbol '__event_mmiotrace_rw' was not declared. Should it be static? kernel/trace/trace_entries.h:298:1: warning: symbol 'event_class_ftrace_mmiotrace_map' was not declared. Should it be static? kernel/trace/trace_entries.h:298:1: warning: symbol '__event_mmiotrace_map' was not declared. Should it be static? kernel/trace/trace_entries.h:322:1: warning: symbol 'event_class_ftrace_branch' was not declared. Should it be static? kernel/trace/trace_entries.h:322:1: warning: symbol '__event_branch' was not declared. Should it be static? kernel/trace/trace_entries.h:343:1: warning: symbol 'event_class_ftrace_hwlat' was not declared. Should it be static? kernel/trace/trace_entries.h:343:1: warning: symbol '__event_hwlat' was not declared. Should it be static? Link: http://lkml.kernel.org/r/20191015121012.18824-1-ben.dooks@codethink.co.uk Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13tracing: Use CONFIG_PREEMPTIONSebastian Andrzej Siewior1-0/+2
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Add additional header output for PREEMPT_RT. Link: http://lkml.kernel.org/r/20191015191821.11479-34-bigeasy@linutronix.de Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13preemptirq_delay_test: Add the burst feature and a sysfs triggerViktor Rosendahl (BMW)2-22/+128
This burst feature enables the user to generate a burst of preempt/irqsoff latencies. This makes it possible to test whether we are able to detect latencies that systematically occur very close to each other. The maximum burst size is 10. We also create 10 identical test functions, so that we get 10 different backtraces; this is useful when we want to test whether we can detect all the latencies in a burst. Otherwise, there would be no easy way of differentiating between which latency in a burst was captured by the tracer. In addition, there is a sysfs trigger, so that it's not necessary to reload the module to repeat the test. The trigger will appear as /sys/kernel/preemptirq_delay_test/trigger in sysfs. Link: http://lkml.kernel.org/r/20191008220824.7911-3-viktor.rosendahl@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Implement fs notification for tracing_max_latencyViktor Rosendahl (BMW)3-6/+98
This patch implements the feature that the tracing_max_latency file, e.g. /sys/kernel/debug/tracing/tracing_max_latency will receive notifications through the fsnotify framework when a new latency is available. One particularly interesting use of this facility is when enabling threshold tracing, through /sys/kernel/debug/tracing/tracing_thresh, together with the preempt/irqsoff tracers. This makes it possible to implement a user space program that can, with equal probability, obtain traces of latencies that occur immediately after each other in spite of the fact that the preempt/irqsoff tracers operate in overwrite mode. This facility works with the hwlat, preempt/irqsoff, and wakeup tracers. The tracers may call the latency_fsnotify() from places such as __schedule() or do_idle(); this makes it impossible to call queue_work() directly without risking a deadlock. The same would happen with a softirq, kernel thread or tasklet. For this reason we use the irq_work mechanism to call queue_work(). This patch creates a new workqueue. The reason for doing this is that I wanted to use the WQ_UNBOUND and WQ_HIGHPRI flags. My thinking was that WQ_UNBOUND might help with the latency in some important cases. If we use: queue_work(system_highpri_wq, &tr->fsnotify_work); then the work will (almost) always execute on the same CPU but if we are unlucky that CPU could be too busy while there could be another CPU in the system that would be able to process the work soon enough. queue_work_on() could be used to queue the work on another CPU but it seems difficult to select the right CPU. Link: http://lkml.kernel.org/r/20191008220824.7911-2-viktor.rosendahl@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com> [ Added max() to have one compare for max latency ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add information on number of page groups allocatedSteven Rostedt (VMware)3-6/+31
Looking for ways to shrink the size of the dyn_ftrace structure, knowing the information about how many pages and the number of groups of those pages, is useful in working out the best ways to save on memory. This adds one info print on how many groups of pages were used to allocate the ftrace dyn_ftrace structures, and also shows the number of pages and groups in the dyn_ftrace_total_info (which is used for debugging). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Add a counter to test function_graph with directSteven Rostedt (VMware)1-0/+4
As testing for direct calls from the function graph tracer adds a little overhead (which is a lot when tracing every function), add a counter that can be used to test if function_graph tracer needs to test for a direct caller or not. It would have been nicer if we could use a static branch, but the static branch logic fails when used within the function graph tracer trampoline. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add ftrace_find_direct_func()Steven Rostedt (VMware)1-1/+78
As function_graph tracer modifies the return address to insert a trampoline to trace the return of a function, it must be aware of a direct caller, as when it gets called, the function's return address may not be at on the stack where it expects. It may have to see if that return address points to the a direct caller and adjust if it is. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add register_ftrace_direct()Steven Rostedt (VMware)2-5/+272
Add the start of the functionality to allow other trampolines to use the ftrace mcount/fentry/nop location. This adds two new functions: register_ftrace_direct() and unregister_ftrace_direct() Both take two parameters: the first is the instruction address of where the mcount/fentry/nop exists, and the second is the trampoline to have that location called. This will handle cases where ftrace is already used on that same location, and will make it still work, where the registered direct called trampoline will get called after all the registered ftrace callers are handled. Currently, it will not allow for IP_MODIFY functions to be called at the same locations, which include some kprobes and live kernel patching. At this point, no architecture supports this. This is only the start of implementing the framework. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-12cgroup: use cgrp->kn->id as the cgroup IDTejun Heo1-2/+2
cgroup ID is currently allocated using a dedicated per-hierarchy idr and used internally and exposed through tracepoints and bpf. This is confusing because there are tracepoints and other interfaces which use the cgroupfs ino as IDs. The preceding changes made kn->id exposed as ino as 64bit ino on supported archs or ino+gen (low 32bits as ino, high gen). There's no reason for cgroup to use different IDs. The kernfs IDs are unique and userland can easily discover them and map them back to paths using standard file operations. This patch replaces cgroup IDs with kernfs IDs. * cgroup_id() is added and all cgroup ID users are converted to use it. * kernfs_node creation is moved to earlier during cgroup init so that cgroup_id() is available during init. * While at it, s/cgroup/cgrp/ in psi helpers for consistency. * Fallback ID value is changed to 1 to be consistent with root cgroup ID. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-12kernfs: use 64bit inos if ino_t is 64bitTejun Heo1-4/+17
Each kernfs_node is identified with a 64bit ID. The low 32bit is exposed as ino and the high gen. While this already allows using inos as keys by looking up with wildcard generation number of 0, it's adding unnecessary complications for 64bit ino archs which can directly use kernfs_node IDs as inos to uniquely identify each cgroup instance. This patch exposes IDs directly as inos on 64bit ino archs. The conversion is mostly straight-forward. * 32bit ino archs behave the same as before. 64bit ino archs now use the whole 64bit ID as ino and the generation number is fixed at 1. * 64bit inos still use the same idr allocator which gurantees that the lower 32bits identify the current live instance uniquely and the high 32bits are incremented whenever the low bits wrap. As the upper 32bits are no longer used as gen and we don't wanna start ino allocation with 33rd bit set, the initial value for highbits allocation is changed to 0 on 64bit ino archs. * blktrace exposes two 32bit numbers - (INO,GEN) pair - to identify the issuing cgroup. Userland builds FILEID_INO32_GEN fids from these numbers to look up the cgroups. To remain compatible with the behavior, always output (LOW32,HIGH32) which will be constructed back to the original 64bit ID by __kernfs_fh_to_dentry(). Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-12kernfs: convert kernfs_node->id from union kernfs_node_id to u64Tejun Heo1-36/+31
kernfs_node->id is currently a union kernfs_node_id which represents either a 32bit (ino, gen) pair or u64 value. I can't see much value in the usage of the union - all that's needed is a 64bit ID which the current code is already limited to. Using a union makes the code unnecessarily complicated and prevents using 64bit ino without adding practical benefits. This patch drops union kernfs_node_id and makes kernfs_node->id a u64. ino is stored in the lower 32bits and gen upper. Accessors - kernfs[_id]_ino() and kernfs[_id]_gen() - are added to retrieve the ino and gen. This simplifies ID handling less cumbersome and will allow using 64bit inos on supported archs. This patch doesn't make any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexei Starovoitov <ast@kernel.org>
2019-11-11irq_work: Convert flags to atomic_tFrederic Weisbecker1-1/+1
We need to convert flags to atomic_t in order to later fix an ordering issue on atomic_cmpxchg() failure. This will allow us to use atomic_fetch_or(). Also clarify the nature of those flags. [ mingo: Converted two more usage site the original patch missed. ] Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20191108160858.31665-2-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-08ftrace: Separate out functionality from ftrace_location_range()Steven Rostedt (VMware)1-15/+23
Create a new function called lookup_rec() from the functionality of ftrace_location_range(). The difference between lookup_rec() is that it returns the record that it finds, where as ftrace_location_range() returns only if it found a match or not. The lookup_rec() is static, and can be used for new functionality where ftrace needs to find a record of a specific address. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out the copying of a ftrace_hash from __ftrace_hash_move()Steven Rostedt (VMware)1-12/+17
Most of the functionality of __ftrace_hash_move() can be reused, but not all of it. That is, __ftrace_hash_move() is used to simply make a new hash from an existing one, using the same size as the original. Creating a dup_hash(), where we can specify a new size will be useful when we want to create a hash with a default size, or simply copy the old one. Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
2019-11-06ftrace: add ftrace_init_nop()Mark Rutland1-3/+3
Architectures may need to perform special initialization of ftrace callsites, and today they do so by special-casing ftrace_make_nop() when the expected branch address is MCOUNT_ADDR. In some cases (e.g. for patchable-function-entry), we don't have an mcount-like symbol and don't want a synthetic MCOUNT_ADDR, but we may need to perform some initialization of callsites. To make it possible to separate initialization from runtime modification, and to handle cases without an mcount-like symbol, this patch adds an optional ftrace_init_nop() function that architectures can implement, which does not pass a branch address. Where an architecture does not provide ftrace_init_nop(), we will fall back to the existing behaviour of calling ftrace_make_nop() with MCOUNT_ADDR. At the same time, ftrace_code_disable() is renamed to ftrace_nop_initialize() to make it clearer that it is intended to intialize a callsite into a disabled state, and is not for disabling a callsite that has been runtime enabled. The kerneldoc description of rec arguments is updated to cover non-mcount callsites. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Torsten Duwe <duwe@suse.de> Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Tested-by: Sven Schnelle <svens@stackframe.org> Tested-by: Torsten Duwe <duwe@suse.de> Cc: Ingo Molnar <mingo@redhat.com>
2019-11-04ftrace: Introduce PERMANENT ftrace_ops flagMiroslav Benes1-2/+21
Livepatch uses ftrace for redirection to new patched functions. It means that if ftrace is disabled, all live patched functions are disabled as well. Toggling global 'ftrace_enabled' sysctl thus affect it directly. It is not a problem per se, because only administrator can set sysctl values, but it still may be surprising. Introduce PERMANENT ftrace_ops flag to amend this. If the FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be disabled by disabling ftrace_enabled. Equally, a callback with the flag set cannot be registered if ftrace_enabled is disabled. Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>