mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
bb730b5833
The Linux kernel adopted the SPDX License format headers to ease license compliance management, and uses the C++ '//' style comments for the SPDX header tags. Some files in the tracing directory used the C style /* */ comments for them. To be consistent across all files, replace the /* */ C style SPDX tags with the C++ // SPDX tags. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
289 lines
11 KiB
C
289 lines
11 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#ifndef __TRACING_MAP_H
|
|
#define __TRACING_MAP_H
|
|
|
|
#define TRACING_MAP_BITS_DEFAULT 11
|
|
#define TRACING_MAP_BITS_MAX 17
|
|
#define TRACING_MAP_BITS_MIN 7
|
|
|
|
#define TRACING_MAP_KEYS_MAX 3
|
|
#define TRACING_MAP_VALS_MAX 3
|
|
#define TRACING_MAP_FIELDS_MAX (TRACING_MAP_KEYS_MAX + \
|
|
TRACING_MAP_VALS_MAX)
|
|
#define TRACING_MAP_VARS_MAX 16
|
|
#define TRACING_MAP_SORT_KEYS_MAX 2
|
|
|
|
typedef int (*tracing_map_cmp_fn_t) (void *val_a, void *val_b);
|
|
|
|
/*
|
|
* This is an overview of the tracing_map data structures and how they
|
|
* relate to the tracing_map API. The details of the algorithms
|
|
* aren't discussed here - this is just a general overview of the data
|
|
* structures and how they interact with the API.
|
|
*
|
|
* The central data structure of the tracing_map is an initially
|
|
* zeroed array of struct tracing_map_entry (stored in the map field
|
|
* of struct tracing_map). tracing_map_entry is a very simple data
|
|
* structure containing only two fields: a 32-bit unsigned 'key'
|
|
* variable and a pointer named 'val'. This array of struct
|
|
* tracing_map_entry is essentially a hash table which will be
|
|
* modified by a single function, tracing_map_insert(), but which can
|
|
* be traversed and read by a user at any time (though the user does
|
|
* this indirectly via an array of tracing_map_sort_entry - see the
|
|
* explanation of that data structure in the discussion of the
|
|
* sorting-related data structures below).
|
|
*
|
|
* The central function of the tracing_map API is
|
|
* tracing_map_insert(). tracing_map_insert() hashes the
|
|
* arbitrarily-sized key passed into it into a 32-bit unsigned key.
|
|
* It then uses this key, truncated to the array size, as an index
|
|
* into the array of tracing_map_entries. If the value of the 'key'
|
|
* field of the tracing_map_entry found at that location is 0, then
|
|
* that entry is considered to be free and can be claimed, by
|
|
* replacing the 0 in the 'key' field of the tracing_map_entry with
|
|
* the new 32-bit hashed key. Once claimed, that tracing_map_entry's
|
|
* 'val' field is then used to store a unique element which will be
|
|
* forever associated with that 32-bit hashed key in the
|
|
* tracing_map_entry.
|
|
*
|
|
* That unique element now in the tracing_map_entry's 'val' field is
|
|
* an instance of tracing_map_elt, where 'elt' in the latter part of
|
|
* that variable name is short for 'element'. The purpose of a
|
|
* tracing_map_elt is to hold values specific to the particular
|
|
* 32-bit hashed key it's assocated with. Things such as the unique
|
|
* set of aggregated sums associated with the 32-bit hashed key, along
|
|
* with a copy of the full key associated with the entry, and which
|
|
* was used to produce the 32-bit hashed key.
|
|
*
|
|
* When tracing_map_create() is called to create the tracing map, the
|
|
* user specifies (indirectly via the map_bits param, the details are
|
|
* unimportant for this discussion) the maximum number of elements
|
|
* that the map can hold (stored in the max_elts field of struct
|
|
* tracing_map). This is the maximum possible number of
|
|
* tracing_map_entries in the tracing_map_entry array which can be
|
|
* 'claimed' as described in the above discussion, and therefore is
|
|
* also the maximum number of tracing_map_elts that can be associated
|
|
* with the tracing_map_entry array in the tracing_map. Because of
|
|
* the way the insertion algorithm works, the size of the allocated
|
|
* tracing_map_entry array is always twice the maximum number of
|
|
* elements (2 * max_elts). This value is stored in the map_size
|
|
* field of struct tracing_map.
|
|
*
|
|
* Because tracing_map_insert() needs to work from any context,
|
|
* including from within the memory allocation functions themselves,
|
|
* both the tracing_map_entry array and a pool of max_elts
|
|
* tracing_map_elts are pre-allocated before any call is made to
|
|
* tracing_map_insert().
|
|
*
|
|
* The tracing_map_entry array is allocated as a single block by
|
|
* tracing_map_create().
|
|
*
|
|
* Because the tracing_map_elts are much larger objects and can't
|
|
* generally be allocated together as a single large array without
|
|
* failure, they're allocated individually, by tracing_map_init().
|
|
*
|
|
* The pool of tracing_map_elts are allocated by tracing_map_init()
|
|
* rather than by tracing_map_create() because at the time
|
|
* tracing_map_create() is called, there isn't enough information to
|
|
* create the tracing_map_elts. Specifically,the user first needs to
|
|
* tell the tracing_map implementation how many fields the
|
|
* tracing_map_elts contain, and which types of fields they are (key
|
|
* or sum). The user does this via the tracing_map_add_sum_field()
|
|
* and tracing_map_add_key_field() functions, following which the user
|
|
* calls tracing_map_init() to finish up the tracing map setup. The
|
|
* array holding the pointers which make up the pre-allocated pool of
|
|
* tracing_map_elts is allocated as a single block and is stored in
|
|
* the elts field of struct tracing_map.
|
|
*
|
|
* There is also a set of structures used for sorting that might
|
|
* benefit from some minimal explanation.
|
|
*
|
|
* struct tracing_map_sort_key is used to drive the sort at any given
|
|
* time. By 'any given time' we mean that a different
|
|
* tracing_map_sort_key will be used at different times depending on
|
|
* whether the sort currently being performed is a primary or a
|
|
* secondary sort.
|
|
*
|
|
* The sort key is very simple, consisting of the field index of the
|
|
* tracing_map_elt field to sort on (which the user saved when adding
|
|
* the field), and whether the sort should be done in an ascending or
|
|
* descending order.
|
|
*
|
|
* For the convenience of the sorting code, a tracing_map_sort_entry
|
|
* is created for each tracing_map_elt, again individually allocated
|
|
* to avoid failures that might be expected if allocated as a single
|
|
* large array of struct tracing_map_sort_entry.
|
|
* tracing_map_sort_entry instances are the objects expected by the
|
|
* various internal sorting functions, and are also what the user
|
|
* ultimately receives after calling tracing_map_sort_entries().
|
|
* Because it doesn't make sense for users to access an unordered and
|
|
* sparsely populated tracing_map directly, the
|
|
* tracing_map_sort_entries() function is provided so that users can
|
|
* retrieve a sorted list of all existing elements. In addition to
|
|
* the associated tracing_map_elt 'elt' field contained within the
|
|
* tracing_map_sort_entry, which is the object of interest to the
|
|
* user, tracing_map_sort_entry objects contain a number of additional
|
|
* fields which are used for caching and internal purposes and can
|
|
* safely be ignored.
|
|
*/
|
|
|
|
struct tracing_map_field {
|
|
tracing_map_cmp_fn_t cmp_fn;
|
|
union {
|
|
atomic64_t sum;
|
|
unsigned int offset;
|
|
};
|
|
};
|
|
|
|
struct tracing_map_elt {
|
|
struct tracing_map *map;
|
|
struct tracing_map_field *fields;
|
|
atomic64_t *vars;
|
|
bool *var_set;
|
|
void *key;
|
|
void *private_data;
|
|
};
|
|
|
|
struct tracing_map_entry {
|
|
u32 key;
|
|
struct tracing_map_elt *val;
|
|
};
|
|
|
|
struct tracing_map_sort_key {
|
|
unsigned int field_idx;
|
|
bool descending;
|
|
};
|
|
|
|
struct tracing_map_sort_entry {
|
|
void *key;
|
|
struct tracing_map_elt *elt;
|
|
bool elt_copied;
|
|
bool dup;
|
|
};
|
|
|
|
struct tracing_map_array {
|
|
unsigned int entries_per_page;
|
|
unsigned int entry_size_shift;
|
|
unsigned int entry_shift;
|
|
unsigned int entry_mask;
|
|
unsigned int n_pages;
|
|
void **pages;
|
|
};
|
|
|
|
#define TRACING_MAP_ARRAY_ELT(array, idx) \
|
|
(array->pages[idx >> array->entry_shift] + \
|
|
((idx & array->entry_mask) << array->entry_size_shift))
|
|
|
|
#define TRACING_MAP_ENTRY(array, idx) \
|
|
((struct tracing_map_entry *)TRACING_MAP_ARRAY_ELT(array, idx))
|
|
|
|
#define TRACING_MAP_ELT(array, idx) \
|
|
((struct tracing_map_elt **)TRACING_MAP_ARRAY_ELT(array, idx))
|
|
|
|
struct tracing_map {
|
|
unsigned int key_size;
|
|
unsigned int map_bits;
|
|
unsigned int map_size;
|
|
unsigned int max_elts;
|
|
atomic_t next_elt;
|
|
struct tracing_map_array *elts;
|
|
struct tracing_map_array *map;
|
|
const struct tracing_map_ops *ops;
|
|
void *private_data;
|
|
struct tracing_map_field fields[TRACING_MAP_FIELDS_MAX];
|
|
unsigned int n_fields;
|
|
int key_idx[TRACING_MAP_KEYS_MAX];
|
|
unsigned int n_keys;
|
|
struct tracing_map_sort_key sort_key;
|
|
unsigned int n_vars;
|
|
atomic64_t hits;
|
|
atomic64_t drops;
|
|
};
|
|
|
|
/**
|
|
* struct tracing_map_ops - callbacks for tracing_map
|
|
*
|
|
* The methods in this structure define callback functions for various
|
|
* operations on a tracing_map or objects related to a tracing_map.
|
|
*
|
|
* For a detailed description of tracing_map_elt objects please see
|
|
* the overview of tracing_map data structures at the beginning of
|
|
* this file.
|
|
*
|
|
* All the methods below are optional.
|
|
*
|
|
* @elt_alloc: When a tracing_map_elt is allocated, this function, if
|
|
* defined, will be called and gives clients the opportunity to
|
|
* allocate additional data and attach it to the element
|
|
* (tracing_map_elt->private_data is meant for that purpose).
|
|
* Element allocation occurs before tracing begins, when the
|
|
* tracing_map_init() call is made by client code.
|
|
*
|
|
* @elt_free: When a tracing_map_elt is freed, this function is called
|
|
* and allows client-allocated per-element data to be freed.
|
|
*
|
|
* @elt_clear: This callback allows per-element client-defined data to
|
|
* be cleared, if applicable.
|
|
*
|
|
* @elt_init: This callback allows per-element client-defined data to
|
|
* be initialized when used i.e. when the element is actually
|
|
* claimed by tracing_map_insert() in the context of the map
|
|
* insertion.
|
|
*/
|
|
struct tracing_map_ops {
|
|
int (*elt_alloc)(struct tracing_map_elt *elt);
|
|
void (*elt_free)(struct tracing_map_elt *elt);
|
|
void (*elt_clear)(struct tracing_map_elt *elt);
|
|
void (*elt_init)(struct tracing_map_elt *elt);
|
|
};
|
|
|
|
extern struct tracing_map *
|
|
tracing_map_create(unsigned int map_bits,
|
|
unsigned int key_size,
|
|
const struct tracing_map_ops *ops,
|
|
void *private_data);
|
|
extern int tracing_map_init(struct tracing_map *map);
|
|
|
|
extern int tracing_map_add_sum_field(struct tracing_map *map);
|
|
extern int tracing_map_add_var(struct tracing_map *map);
|
|
extern int tracing_map_add_key_field(struct tracing_map *map,
|
|
unsigned int offset,
|
|
tracing_map_cmp_fn_t cmp_fn);
|
|
|
|
extern void tracing_map_destroy(struct tracing_map *map);
|
|
extern void tracing_map_clear(struct tracing_map *map);
|
|
|
|
extern struct tracing_map_elt *
|
|
tracing_map_insert(struct tracing_map *map, void *key);
|
|
extern struct tracing_map_elt *
|
|
tracing_map_lookup(struct tracing_map *map, void *key);
|
|
|
|
extern tracing_map_cmp_fn_t tracing_map_cmp_num(int field_size,
|
|
int field_is_signed);
|
|
extern int tracing_map_cmp_string(void *val_a, void *val_b);
|
|
extern int tracing_map_cmp_none(void *val_a, void *val_b);
|
|
|
|
extern void tracing_map_update_sum(struct tracing_map_elt *elt,
|
|
unsigned int i, u64 n);
|
|
extern void tracing_map_set_var(struct tracing_map_elt *elt,
|
|
unsigned int i, u64 n);
|
|
extern bool tracing_map_var_set(struct tracing_map_elt *elt, unsigned int i);
|
|
extern u64 tracing_map_read_sum(struct tracing_map_elt *elt, unsigned int i);
|
|
extern u64 tracing_map_read_var(struct tracing_map_elt *elt, unsigned int i);
|
|
extern u64 tracing_map_read_var_once(struct tracing_map_elt *elt, unsigned int i);
|
|
|
|
extern void tracing_map_set_field_descr(struct tracing_map *map,
|
|
unsigned int i,
|
|
unsigned int key_offset,
|
|
tracing_map_cmp_fn_t cmp_fn);
|
|
extern int
|
|
tracing_map_sort_entries(struct tracing_map *map,
|
|
struct tracing_map_sort_key *sort_keys,
|
|
unsigned int n_sort_keys,
|
|
struct tracing_map_sort_entry ***sort_entries);
|
|
|
|
extern void
|
|
tracing_map_destroy_sort_entries(struct tracing_map_sort_entry **entries,
|
|
unsigned int n_entries);
|
|
#endif /* __TRACING_MAP_H */
|