linux/kernel/trace/Kconfig, branch v6.3

Merge tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2023-02-23T18:20:49Z

Pull tracing updates from Steven Rostedt: - Add function names as a way to filter function addresses - Add sample module to test ftrace ops and dynamic trampolines - Allow stack traces to be passed from beginning event to end event for synthetic events. This will allow seeing the stack trace of when a task is scheduled out and recorded when it gets scheduled back in. - Add trace event helper __get_buf() to use as a temporary buffer when printing out trace event output. - Add kernel command line to create trace instances on boot up. - Add enabling of events to instances created at boot up. - Add trace_array_puts() to write into instances. - Allow boot instances to take a snapshot at the end of boot up. - Allow live patch modules to include trace events - Minor fixes and clean ups * tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits) tracing: Remove unnecessary NULL assignment tracepoint: Allow livepatch module add trace event tracing: Always use canonical ftrace path tracing/histogram: Fix stacktrace histogram Documententation tracing/histogram: Fix stacktrace key tracing/histogram: Fix a few problems with stacktrace variable printing tracing: Add BUILD_BUG() to make sure stacktrace fits in strings tracing/histogram: Don't use strlen to find length of stacktrace variables tracing: Allow boot instances to have snapshot buffers tracing: Add trace_array_puts() to write into instance tracing: Add enabling of events to boot instances tracing: Add creation of instances at boot command line tracing: Fix trace_event_raw_event_synth() if else statement samples: ftrace: Make some global variables static ftrace: sample: avoid open-coded 64-bit division samples: ftrace: Include the nospec-branch.h only for x86 tracing: Acquire buffer from temparary trace sequence tracing/histogram: Wrap remaining shell snippets in code blocks tracing/osnoise: No need for schedule_hrtimeout range bpf/tracing: Use stage6 of tracing to not duplicate macros ...

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2023-02-21T23:27:48Z

Pull arm64 updates from Catalin Marinas: - Support for arm64 SME 2 and 2.1. SME2 introduces a new 512-bit architectural register (ZT0, for the look-up table feature) that Linux needs to save/restore - Include TPIDR2 in the signal context and add the corresponding kselftests - Perf updates: Arm SPEv1.2 support, HiSilicon uncore PMU updates, ACPI support to the Marvell DDR and TAD PMU drivers, reset DTM_PMU_CONFIG (ARM CMN) at probe time - Support for DYNAMIC_FTRACE_WITH_CALL_OPS on arm64 - Permit EFI boot with MMU and caches on. Instead of cleaning the entire loaded kernel image to the PoC and disabling the MMU and caches before branching to the kernel bare metal entry point, leave the MMU and caches enabled and rely on EFI's cacheable 1:1 mapping of all of system RAM to populate the initial page tables - Expose the AArch32 (compat) ELF_HWCAP features to user in an arm64 kernel (the arm32 kernel only defines the values) - Harden the arm64 shadow call stack pointer handling: stash the shadow stack pointer in the task struct on interrupt, load it directly from this structure - Signal handling cleanups to remove redundant validation of size information and avoid reading the same data from userspace twice - Refactor the hwcap macros to make use of the automatically generated ID registers. It should make new hwcaps writing less error prone - Further arm64 sysreg conversion and some fixes - arm64 kselftest fixes and improvements - Pointer authentication cleanups: don't sign leaf functions, unify asm-arch manipulation - Pseudo-NMI code generation optimisations - Minor fixes for SME and TPIDR2 handling - Miscellaneous updates: ARCH_FORCE_MAX_ORDER is now selectable, replace strtobool() to kstrtobool() in the cpufeature.c code, apply dynamic shadow call stack in two passes, intercept pfn changes in set_pte_at() without the required break-before-make sequence, attempt to dump all instructions on unhandled kernel faults * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (130 commits) arm64: fix .idmap.text assertion for large kernels kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests kselftest/arm64: Copy whole EXTRA context arm64: kprobes: Drop ID map text from kprobes blacklist perf: arm_spe: Print the version of SPE detected perf: arm_spe: Add support for SPEv1.2 inverted event filtering perf: Add perf_event_attr::config3 arm64/sme: Fix __finalise_el2 SMEver check drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable arm64/signal: Only read new data when parsing the ZT context arm64/signal: Only read new data when parsing the ZA context arm64/signal: Only read new data when parsing the SVE context arm64/signal: Avoid rereading context frame sizes arm64/signal: Make interface for restore_fpsimd_context() consistent arm64/signal: Remove redundant size validation from parse_user_sigframe() arm64/signal: Don't redundantly verify FPSIMD magic arm64/cpufeature: Use helper macros to specify hwcaps arm64/cpufeature: Always use symbolic name for feature value in hwcaps arm64/sysreg: Initial unsigned annotations for ID registers arm64/sysreg: Initial annotation of signed ID registers ...

tracing: Always use canonical ftrace path

2023-02-18T19:34:09Z

The canonical location for the tracefs filesystem is at /sys/kernel/tracing. But, from Documentation/trace/ftrace.rst: Before 4.1, all ftrace tracing control files were within the debugfs file system, which is typically located at /sys/kernel/debug/tracing. For backward compatibility, when mounting the debugfs file system, the tracefs file system will be automatically mounted at: /sys/kernel/debug/tracing Many comments and Kconfig help messages in the tracing code still refer to this older debugfs path, so let's update them to avoid confusion. Link: https://lore.kernel.org/linux-trace-kernel/20230215223350.2658616-2-zwisler@google.com Acked-by: Masami Hiramatsu (Google) Reviewed-by: Mukesh Ojha Signed-off-by: Ross Zwisler Signed-off-by: Steven Rostedt (Google)

tracing: Kconfig: Fix spelling/grammar/punctuation

2023-01-24T18:22:38Z

Fix some editorial nits in trace Kconfig. Link: https://lkml.kernel.org/r/20230124181647.15902-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Signed-off-by: Steven Rostedt (Google)

ftrace: Add DYNAMIC_FTRACE_WITH_CALL_OPS

2023-01-24T11:49:42Z

Architectures without dynamic ftrace trampolines incur an overhead when multiple ftrace_ops are enabled with distinct filters. in these cases, each call site calls a common trampoline which uses ftrace_ops_list_func() to iterate over all enabled ftrace functions, and so incurs an overhead relative to the size of this list (including RCU protection overhead). Architectures with dynamic ftrace trampolines avoid this overhead for call sites which have a single associated ftrace_ops. In these cases, the dynamic trampoline is customized to branch directly to the relevant ftrace function, avoiding the list overhead. On some architectures it's impractical and/or undesirable to implement dynamic ftrace trampolines. For example, arm64 has limited branch ranges and cannot always directly branch from a call site to an arbitrary address (e.g. from a kernel text address to an arbitrary module address). Calls from modules to core kernel text can be indirected via PLTs (allocated at module load time) to address this, but the same is not possible from calls from core kernel text. Using an indirect branch from a call site to an arbitrary trampoline is possible, but requires several more instructions in the function prologue (or immediately before it), and/or comes with far more complex requirements for patching. Instead, this patch adds a new option, where an architecture can associate each call site with a pointer to an ftrace_ops, placed at a fixed offset from the call site. A shared trampoline can recover this pointer and call ftrace_ops::func() without needing to go via ftrace_ops_list_func(), avoiding the associated overhead. This avoids issues with branch range limitations, and avoids the need to allocate and manipulate dynamic trampolines, making it far simpler to implement and maintain, while having similar performance characteristics. Note that this allows for dynamic ftrace_ops to be invoked directly from an architecture's ftrace_caller trampoline, whereas existing code forces the use of ftrace_ops_get_list_func(), which is in part necessary to permit the ftrace_ops to be freed once unregistered *and* to avoid branch/address-generation range limitation on some architectures (e.g. where ops->func is a module address, and may be outside of the direct branch range for callsites within the main kernel image). The CALL_OPS approach avoids this problems and is safe as: * The existing synchronization in ftrace_shutdown() using ftrace_shutdown() using synchronize_rcu_tasks_rude() (and synchronize_rcu_tasks()) ensures that no tasks hold a stale reference to an ftrace_ops (e.g. in the middle of the ftrace_caller trampoline, or while invoking ftrace_ops::func), when that ftrace_ops is unregistered. Arguably this could also be relied upon for the existing scheme, permitting dynamic ftrace_ops to be invoked directly when ops->func is in range, but this will require additional logic to handle branch range limitations, and is not handled by this patch. * Each callsite's ftrace_ops pointer literal can hold any valid kernel address, and is updated atomically. As an architecture's ftrace_caller trampoline will atomically load the ops pointer then dereference ops->func, there is no risk of invoking ops->func with a mismatches ops pointer, and updates to the ops pointer do not require special care. A subsequent patch will implement architectures support for arm64. There should be no functional change as a result of this patch alone. Signed-off-by: Mark Rutland Reviewed-by: Steven Rostedt (Google) Cc: Florent Revest Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Will Deacon Link: https://lore.kernel.org/r/20230123134603.1064407-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas

Merge tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2022-12-19T13:13:33Z

Pull powerpc updates from Michael Ellerman: - Add powerpc qspinlock implementation optimised for large system scalability and paravirt. See the merge message for more details - Enable objtool to be built on powerpc to generate mcount locations - Use a temporary mm for code patching with the Radix MMU, so the writable mapping is restricted to the patching CPU - Add an option to build the 64-bit big-endian kernel with the ELFv2 ABI - Sanitise user registers on interrupt entry on 64-bit Book3S - Many other small features and fixes Thanks to Aboorva Devarajan, Angel Iglesias, Benjamin Gray, Bjorn Helgaas, Bo Liu, Chen Lifu, Christoph Hellwig, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Deming Wang, Disha Goel, Dmitry Torokhov, Finn Thain, Geert Uytterhoeven, Gustavo A. R. Silva, Haowen Bai, Joel Stanley, Jordan Niethe, Julia Lawall, Kajol Jain, Laurent Dufour, Li zeming, Miaoqian Lin, Michael Jeanson, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Randy Dunlap, Rohan McLure, Russell Currey, Sathvika Vasireddy, Shaomin Deng, Stephen Kitt, Stephen Rothwell, Thomas Weißschuh, Tiezhu Yang, Uwe Kleine-König, Xie Shaowen, Xiu Jianfeng, XueBing Chen, Yang Yingliang, Zhang Jiaming, ruanjinjie, Jessica Yu, and Wolfram Sang. * tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (181 commits) powerpc/code-patching: Fix oops with DEBUG_VM enabled powerpc/qspinlock: Fix 32-bit build powerpc/prom: Fix 32-bit build powerpc/rtas: mandate RTAS syscall filtering powerpc/rtas: define pr_fmt and convert printk call sites powerpc/rtas: clean up includes powerpc/rtas: clean up rtas_error_log_max initialization powerpc/pseries/eeh: use correct API for error log size powerpc/rtas: avoid scheduling in rtas_os_term() powerpc/rtas: avoid device tree lookups in rtas_os_term() powerpc/rtasd: use correct OF API for event scan rate powerpc/rtas: document rtas_call() powerpc/pseries: unregister VPA when hot unplugging a CPU powerpc/pseries: reset the RCU watchdogs after a LPM powerpc: Take in account addition CPU node when building kexec FDT powerpc: export the CPU node count powerpc/cpuidle: Set CPUIDLE_FLAG_POLLING for snooze state powerpc/dts/fsl: Fix pca954x i2c-mux node names cxl: Remove unnecessary cxl_pci_window_alignment() selftests/powerpc: Fix resource leaks ...

Merge tag 'trace-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2022-12-16T02:01:16Z

Pull tracing updates from Steven Rostedt: - Add options to the osnoise tracer: - 'panic_on_stop' option that panics the kernel if osnoise is greater than some user defined threshold. - 'preempt' option, to test noise while preemption is disabled - 'irq' option, to test noise when interrupts are disabled - Add .percent and .graph suffix to histograms to give different outputs - Add nohitcount to disable showing hitcount in histogram output - Add new __cpumask() to trace event fields to annotate that a unsigned long array is a cpumask to user space and should be treated as one. - Add trace_trigger kernel command line parameter to enable trace event triggers at boot up. Useful to trace stack traces, disable tracing and take snapshots. - Fix x86/kmmio mmio tracer to work with the updates to lockdep - Unify the panic and die notifiers - Add back ftrace_expect reference that is used to extract more information in the ftrace_bug() code. - Have trigger filter parsing errors show up in the tracing error log. - Updated MAINTAINERS file to add kernel tracing mailing list and patchwork info - Use IDA to keep track of event type numbers. - And minor fixes and clean ups * tag 'trace-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (44 commits) tracing: Fix cpumask() example typo tracing: Improve panic/die notifiers ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY kernels tracing: Do not synchronize freeing of trigger filter on boot up tracing: Remove pointer (asterisk) and brackets from cpumask_t field tracing: Have trigger filter parsing errors show up in error_log x86/mm/kmmio: Remove redundant preempt_disable() tracing: Fix infinite loop in tracing_read_pipe on overflowed print_trace_line Documentation/osnoise: Add osnoise/options documentation tracing/osnoise: Add preempt and/or irq disabled options tracing/osnoise: Add PANIC_ON_STOP option Documentation/osnoise: Escape underscore of NO_ prefix tracing: Fix some checker warnings tracing/osnoise: Make osnoise_options static tracing: remove unnecessary trace_trigger ifdef ring-buffer: Handle resize in early boot up tracing/hist: Fix issue of losting command info in error_log tracing: Fix issue of missing one synthetic field tracing/hist: Fix out-of-bound write on 'action_data.var_ref_idx' tracing/hist: Fix wrong return value in parse_action_params() ...

tracing: Fix complicated dependency of CONFIG_TRACER_MAX_TRACE

2022-12-10T04:48:05Z

Both CONFIG_OSNOISE_TRACER and CONFIG_HWLAT_TRACER partially enables the CONFIG_TRACER_MAX_TRACE code, but that is complicated and has introduced a bug; It declares tracing_max_lat_fops data structure outside of #ifdefs, but since it is defined only when CONFIG_TRACER_MAX_TRACE=y or CONFIG_HWLAT_TRACER=y, if only CONFIG_OSNOISE_TRACER=y, that declaration comes to a definition(!). To fix this issue, and do not repeat the similar problem, makes CONFIG_OSNOISE_TRACER and CONFIG_HWLAT_TRACER enables the CONFIG_TRACER_MAX_TRACE always. It has there benefits; - Fix the tracing_max_lat_fops bug - Simplify the #ifdefs - CONFIG_TRACER_MAX_TRACE code is fully enabled, or not. Link: https://lore.kernel.org/linux-trace-kernel/167033628155.4111793.12185405690820208159.stgit@devnote3 Fixes: 424b650f35c7 ("tracing: Fix missing osnoise tracer on max_latency") Cc: Daniel Bristot de Oliveira Cc: stable@vger.kernel.org Reported-by: David Howells Reported-by: kernel test robot Signed-off-by: Masami Hiramatsu (Google) Link: https://lore.kernel.org/all/166992525941.1716618.13740663757583361463.stgit@warthog.procyon.org.uk/ (original thread and v1) Link: https://lore.kernel.org/all/202212052253.VuhZ2ulJ-lkp@intel.com/T/#u (v1 error report) Signed-off-by: Steven Rostedt (Google)

ftrace: abstract DYNAMIC_FTRACE_WITH_ARGS accesses

2022-11-18T13:56:41Z

In subsequent patches we'll arrange for architectures to have an ftrace_regs which is entirely distinct from pt_regs. In preparation for this, we need to minimize the use of pt_regs to where strictly necessary in the core ftrace code. This patch adds new ftrace_regs_{get,set}_*() helpers which can be used to manipulate ftrace_regs. When CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=y, these can always be used on any ftrace_regs, and when CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS=n these can be used when regs are available. A new ftrace_regs_has_args(fregs) helper is added which code can use to check when these are usable. Co-developed-by: Florent Revest Signed-off-by: Florent Revest Signed-off-by: Mark Rutland Cc: Masami Hiramatsu Cc: Steven Rostedt Reviewed-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) Link: https://lore.kernel.org/r/20221103170520.931305-4-mark.rutland@arm.com Signed-off-by: Will Deacon

objtool: Add --mnop as an option to --mcount

2022-11-18T08:00:16Z

Some architectures (powerpc) may not support ftrace locations being nop'ed out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as a means for architectures to enable nop'ing of ftrace locations. Add --mnop as an option to objtool --mcount, to indicate support for the same. Also, make sure that --mnop can be passed as an option to objtool only when --mcount is passed. Tested-by: Naveen N. Rao Reviewed-by: Naveen N. Rao Acked-by: Josh Poimboeuf Reviewed-by: Christophe Leroy Signed-off-by: Sathvika Vasireddy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221114175754.1131267-12-sv@linux.ibm.com