From 22098763a10d9c1340827fcf6edab66f153b27f0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 13 Sep 2026 12:27:00 -0700 Subject: Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ... --- tools/perf/util/sample.h | 268 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 268 insertions(+) create mode 100644 tools/perf/util/sample.h (limited to 'tools/perf/util/sample.h') diff --git a/tools/perf/util/sample.h b/tools/perf/util/sample.h new file mode 100644 index 000000000..c4eae8b2f --- /dev/null +++ b/tools/perf/util/sample.h @@ -0,0 +1,268 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_SAMPLE_H +#define __PERF_SAMPLE_H + +#include +#include + +struct evsel; +struct machine; +struct thread; + +/* number of register is bound by the number of bits in regs_dump::mask (64) */ +#define PERF_SAMPLE_REGS_CACHE_SIZE (8 * sizeof(u64)) + +struct regs_dump { + u64 abi; + u64 mask; + u64 *regs; + + /* Cached values/mask filled by first register access. */ + u64 cache_regs[PERF_SAMPLE_REGS_CACHE_SIZE]; + u64 cache_mask; +}; + +struct stack_dump { + u16 offset; + u64 size; + char *data; +}; + +struct sample_read_value { + u64 value; + u64 id; /* only if PERF_FORMAT_ID */ + u64 lost; /* only if PERF_FORMAT_LOST */ +}; + +struct sample_read { + u64 time_enabled; + u64 time_running; + union { + struct { + u64 nr; + struct sample_read_value *values; + } group; + struct sample_read_value one; + }; +}; + +static inline size_t sample_read_value_size(u64 read_format) +{ + /* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */ + if (read_format & PERF_FORMAT_LOST) + return sizeof(struct sample_read_value); + else + return offsetof(struct sample_read_value, lost); +} + +static inline struct sample_read_value *next_sample_read_value(struct sample_read_value *v, u64 read_format) +{ + return (void *)v + sample_read_value_size(read_format); +} + +#define sample_read_group__for_each(v, nr, rf) \ + for (int __i = 0; __i < (int)nr; v = next_sample_read_value(v, rf), __i++) + +#define MAX_INSN 16 + +struct aux_sample { + u64 size; + void *data; +}; + +struct simd_flags { + u8 arch: 2, /* architecture (isa) */ + pred: 3, /* predication */ + resv: 3; /* reserved */ +}; + +/* simd architecture flags */ +enum simd_op_flags { + SIMD_OP_FLAGS_ARCH_NONE = 0x0, /* No SIMD operation */ + SIMD_OP_FLAGS_ARCH_SVE, /* Arm SVE */ + SIMD_OP_FLAGS_ARCH_SME, /* Arm SME */ + SIMD_OP_FLAGS_ARCH_ASE, /* Arm Advanced SIMD */ +}; + +/* simd predicate flags */ +enum simd_pred_flags { + SIMD_OP_FLAGS_PRED_NONE = 0x0, /* Not available */ + SIMD_OP_FLAGS_PRED_PARTIAL, /* partial predicate */ + SIMD_OP_FLAGS_PRED_EMPTY, /* empty predicate */ + SIMD_OP_FLAGS_PRED_FULL, /* full predicate */ + SIMD_OP_FLAGS_PRED_DISABLED, /* disabled predicate */ +}; + +/** + * struct perf_sample + * + * A sample is generally filled in by evlist__parse_sample/evsel__parse_sample + * which fills in the variables from a "union perf_event *event" which is data + * from a perf ring buffer or perf.data file. The "event" sample is variable in + * length as determined by the perf_event_attr (in the evsel) and details within + * the sample event itself. A struct perf_sample avoids needing to care about + * the variable length nature of the original event. + * + * To avoid being excessively large parts of the struct perf_sample are pointers + * into the original sample event. In general the lifetime of a struct + * perf_sample needs to be less than the "union perf_event *event" it was + * derived from. + * + * The struct regs_dump user_regs and intr_regs are lazily allocated again for + * size reasons, due to them holding a cache of looked up registers. The + * function pair of perf_sample__init and perf_sample__exit correctly initialize + * and clean up these values. + */ +struct perf_sample { + /** @evsel: Backward reference to the evsel used when constructing the sample. */ + struct evsel *evsel; + /** @ip: The sample event PERF_SAMPLE_IP value. */ + u64 ip; + /** @pid: The sample event PERF_SAMPLE_TID pid value. */ + u32 pid; + /** @tid: The sample event PERF_SAMPLE_TID tid value. */ + u32 tid; + /** @time: The sample event PERF_SAMPLE_TIME value. */ + u64 time; + /** @addr: The sample event PERF_SAMPLE_ADDR value. */ + u64 addr; + /** @id: The sample event PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER value. */ + u64 id; + /** @stream_id: The sample event PERF_SAMPLE_STREAM_ID value. */ + u64 stream_id; + /** @period: The sample event PERF_SAMPLE_PERIOD value. */ + u64 period; + /** @weight: Data determined by PERF_SAMPLE_WEIGHT or PERF_SAMPLE_WEIGHT_STRUCT. */ + u64 weight; + /** @transaction: The sample event PERF_SAMPLE_TRANSACTION value. */ + u64 transaction; + /** @insn_cnt: Filled in and used by intel-pt. */ + u64 insn_cnt; + /** @cyc_cnt: Filled in and used by intel-pt. */ + u64 cyc_cnt; + /** @cpu: The sample event PERF_SAMPLE_CPU value. */ + u32 cpu; + /** + * @raw_size: The size in bytes of raw data from PERF_SAMPLE_RAW. For + * alignment reasons this should always be sizeof(u32) + * followed by a multiple of sizeof(u64). + */ + u32 raw_size; + /** @data_src: The sample event PERF_SAMPLE_DATA_SRC value. */ + u64 data_src; + /** @phys_addr: The sample event PERF_SAMPLE_PHYS_ADDR value. */ + u64 phys_addr; + /** @data_page_size: The sample event PERF_SAMPLE_DATA_PAGE_SIZE value. */ + u64 data_page_size; + /** @code_page_size: The sample event PERF_SAMPLE_CODE_PAGE_SIZE value. */ + u64 code_page_size; + /** @cgroup: The sample event PERF_SAMPLE_CGROUP value. */ + u64 cgroup; + /** @file_offset: Byte offset of this event in the perf.data file. */ + u64 file_offset; + /** @flags: Extra flag data from auxiliary events like intel-pt. */ + u32 flags; + /** @machine_pid: The guest machine pid derived from the sample id. */ + u32 machine_pid; + /** @vcpu: The guest machine vcpu derived from the sample id. */ + u32 vcpu; + /** + * @insn_len: Instruction length from auxiliary events like + * intel-pt. The instruction itself is held in insn. + */ + u16 insn_len; + /** @misc: The entire struct perf_event_header misc variable. */ + u16 misc; + /** + * @ins_lat: Instruction latency information from weight2 in + * PERF_SAMPLE_WEIGHT_STRUCT or auxiliary events like + * intel-pt. + */ + u16 ins_lat; + /** + * @weight3: From PERF_SAMPLE_WEIGHT_STRUCT. On x86 holds retire_lat, on + * powerpc holds p_stage_cyc. + */ + u16 weight3; + /** + * @cpumode: The cpumode from struct perf_event_header misc variable + * masked with CPUMODE_MASK. Gives user, kernel and hypervisor + * information. + */ + u8 cpumode; + /** + * @no_hw_idx: For PERF_SAMPLE_BRANCH_STACK, true when + * PERF_SAMPLE_BRANCH_HW_INDEX isn't set. + */ + bool no_hw_idx; + /** + * @deferred_callchain: When processing PERF_SAMPLE_CALLCHAIN a deferred + * user callchain marker was encountered. + */ + bool deferred_callchain; + /** + * @merged_callchain: A synthesized merged callchain that is allocated + * and needs freeing. + */ + bool merged_callchain; + /** + * @deferred_cookie: Identifier of the deferred callchain in the later + * PERF_RECORD_CALLCHAIN_DEFERRED event. + */ + u64 deferred_cookie; + /** @insn: A copy of the sampled instruction filled in by perf_sample__fetch_insn. */ + char insn[MAX_INSN]; + /** @raw_data: Pointer into the original event for PERF_SAMPLE_RAW data. */ + void *raw_data; + /** + * @callchain: Pointer into the original event for PERF_SAMPLE_CALLCHAIN + * data. For deferred callchains this may be a copy that + * needs freeing, see sample__merge_deferred_callchain. + */ + struct ip_callchain *callchain; + /** @branch_stack: Pointer into the original event for PERF_SAMPLE_BRANCH_STACK data. */ + struct branch_stack *branch_stack; + /** + * @branch_stack_cntr: Pointer into the original event for + * PERF_SAMPLE_BRANCH_COUNTERS data. + */ + u64 *branch_stack_cntr; + /** @user_regs: Values and pointers into the sample for PERF_SAMPLE_REGS_USER. */ + struct regs_dump *user_regs; + /** @intr_regs: Values and pointers into the sample for PERF_SAMPLE_REGS_INTR. */ + struct regs_dump *intr_regs; + /** @user_stack: Size and pointer into the sample for PERF_SAMPLE_STACK_USER. */ + struct stack_dump user_stack; + /** + * @read: The sample event PERF_SAMPLE_READ counter values. The valid + * values depend on the attr.read_format PERF_FORMAT_ values. + */ + struct sample_read read; + /** + * @aux_sample: Similar to raw data but with a 64-bit size and + * alignment, PERF_SAMPLE_AUX data. + */ + struct aux_sample aux_sample; + /** @simd_flags: SIMD flag information from ARM SPE auxiliary events. */ + struct simd_flags simd_flags; +}; + +void perf_sample__init(struct perf_sample *sample, bool all); +void perf_sample__exit(struct perf_sample *sample); +struct regs_dump *perf_sample__user_regs(struct perf_sample *sample); +struct regs_dump *perf_sample__intr_regs(struct perf_sample *sample); + +void perf_sample__fetch_insn(struct perf_sample *sample, + struct thread *thread, + struct machine *machine); + +/* + * raw_data is always 4 bytes from an 8-byte boundary, so subtract 4 to get + * 8-byte alignment. + */ +static inline void *perf_sample__synth_ptr(struct perf_sample *sample) +{ + return sample->raw_data - 4; +} + +#endif /* __PERF_SAMPLE_H */ -- cgit v1.3.1