tools/lib/perf/include/internal/evsel.h

Source file repositories/reference/linux-study-clean/tools/lib/perf/include/internal/evsel.h

File Facts

System
Linux kernel
Corpus path
tools/lib/perf/include/internal/evsel.h
Extension
.h
Size
5252 bytes
Lines
154
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct perf_sample_id_period {
	struct list_head	node;
	struct hlist_node	hnode;
	/* Holds total ID period value for PERF_SAMPLE_READ processing. */
	u64			period;
	/* The TID that the values belongs to */
	u32			tid;
};

/**
 * perf_evsel_for_each_per_thread_period_safe - safely iterate thru all the
 * per_stream_periods
 * @evlist:perf_evsel instance to iterate
 * @item: struct perf_sample_id_period iterator
 * @tmp: struct perf_sample_id_period temp iterator
 */
#define perf_evsel_for_each_per_thread_period_safe(evsel, tmp, item) \
	list_for_each_entry_safe(item, tmp, &(evsel)->per_stream_periods, node)


#define PERF_SAMPLE_ID__HLIST_BITS 4
#define PERF_SAMPLE_ID__HLIST_SIZE (1 << PERF_SAMPLE_ID__HLIST_BITS)

/*
 * Per fd, to map back from PERF_SAMPLE_ID to evsel, only used when there are
 * more than one entry in the evlist.
 */
struct perf_sample_id {
	struct hlist_node	 node;
	u64			 id;
	struct perf_evsel	*evsel;
       /*
	* 'idx' will be used for AUX area sampling. A sample will have AUX area
	* data that will be queued for decoding, where there are separate
	* queues for each CPU (per-cpu tracing) or task (per-thread tracing).
	* The sample ID can be used to lookup 'idx' which is effectively the
	* queue number.
	*/
	int			 idx;
	struct perf_cpu		 cpu;
	pid_t			 tid;

	/* Guest machine pid and VCPU, valid only if machine_pid is non-zero */
	pid_t			 machine_pid;
	struct perf_cpu		 vcpu;

	/*
	 * Per-thread, and global event counts are mutually exclusive:
	 * Whilst it is possible to combine events into a group with differing
	 * values of PERF_SAMPLE_READ, it is not valid to have inconsistent
	 * values for `inherit`. Therefore it is not possible to have a
	 * situation where a per-thread event is sampled as a global event;
	 * all !inherit groups are global, and all groups where the sampling
	 * event is inherit + PERF_SAMPLE_READ will be per-thread. Any event
	 * that is part of such a group that is inherit but not PERF_SAMPLE_READ
	 * will be read as per-thread. If such an event can also trigger a
	 * sample (such as with sample_period > 0) then it will not cause
	 * `read_format` to be included in its PERF_RECORD_SAMPLE, and
	 * therefore will not expose the per-thread group members as global.
	 */
	union {
		/*
		 * Holds total ID period value for PERF_SAMPLE_READ processing
		 * (when period is not per-thread).
		 */
		u64			period;
		/*
		 * Holds total ID period value for PERF_SAMPLE_READ processing
		 * (when period is per-thread).
		 */
		struct hlist_head	periods[PERF_SAMPLE_ID__HLIST_SIZE];
	};
};

struct perf_evsel {
	struct list_head	 node;
	struct perf_event_attr	 attr;
	/** The commonly used cpu map of CPUs the event should be opened upon, etc. */
	struct perf_cpu_map	*cpus;
	/**
	 * The cpu map read from the PMU. For core PMUs this is the list of all
	 * CPUs the event can be opened upon. For other PMUs this is the default
	 * cpu map for opening the event on, for example, the first CPU on a
	 * socket for an uncore event.
	 */
	struct perf_cpu_map	*pmu_cpus;
	struct perf_thread_map	*threads;
	struct xyarray		*fd;
	struct xyarray		*mmap;
	struct xyarray		*sample_id;

Annotation

Implementation Notes