callchain.h

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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __PERF_CALLCHAIN_H
#define __PERF_CALLCHAIN_H

#include "../perf.h"
#include <linux/list.h>
#include <linux/rbtree.h>
#include "event.h"
#include "map.h"
#include "symbol.h"
#include "branch.h"

#define HELP_PAD "\t\t\t\t"

#define CALLCHAIN_HELP "setup and enables call-graph (stack chain/backtrace):\n\n"

# define RECORD_MODE_HELP  HELP_PAD "record_mode:\tcall graph recording mode (fp|dwarf|lbr)\n"

#define RECORD_SIZE_HELP                        \
    HELP_PAD "record_size:\tif record_mode is 'dwarf', max size of stack recording (<bytes>)\n" \
    HELP_PAD "\t\tdefault: 8192 (bytes)\n"

#define CALLCHAIN_RECORD_HELP  CALLCHAIN_HELP RECORD_MODE_HELP RECORD_SIZE_HELP

#define CALLCHAIN_REPORT_HELP                       \
    HELP_PAD "print_type:\tcall graph printing style (graph|flat|fractal|folded|none)\n" \
    HELP_PAD "threshold:\tminimum call graph inclusion threshold (<percent>)\n" \
    HELP_PAD "print_limit:\tmaximum number of call graph entry (<number>)\n" \
    HELP_PAD "order:\t\tcall graph order (caller|callee)\n" \
    HELP_PAD "sort_key:\tcall graph sort key (function|address)\n"  \
    HELP_PAD "branch:\t\tinclude last branch info to call graph (branch)\n" \
    HELP_PAD "value:\t\tcall graph value (percent|period|count)\n"

enum perf_call_graph_mode {
    CALLCHAIN_NONE,
    CALLCHAIN_FP,
    CALLCHAIN_DWARF,
    CALLCHAIN_LBR,
    CALLCHAIN_MAX
};

enum chain_mode {
    CHAIN_NONE,
    CHAIN_FLAT,
    CHAIN_GRAPH_ABS,
    CHAIN_GRAPH_REL,
    CHAIN_FOLDED,
};

enum chain_order {
    ORDER_CALLER,
    ORDER_CALLEE
};

struct callchain_node {
    struct callchain_node   *parent;
    struct list_head    val;
    struct list_head    parent_val;
    struct rb_node      rb_node_in; /* to insert nodes in an rbtree */
    struct rb_node      rb_node;    /* to sort nodes in an output tree */
    struct rb_root      rb_root_in; /* input tree of children */
    struct rb_root      rb_root;    /* sorted output tree of children */
    unsigned int        val_nr;
    unsigned int        count;
    unsigned int        children_count;
    u64         hit;
    u64         children_hit;
};

struct callchain_root {
    u64         max_depth;
    struct callchain_node   node;
};

struct callchain_param;

typedef void (*sort_chain_func_t)(struct rb_root *, struct callchain_root *,
                 u64, struct callchain_param *);

enum chain_key {
    CCKEY_FUNCTION,
    CCKEY_ADDRESS,
    CCKEY_SRCLINE
};

enum chain_value {
    CCVAL_PERCENT,
    CCVAL_PERIOD,
    CCVAL_COUNT,
};

extern bool dwarf_callchain_users;

struct callchain_param {
    bool            enabled;
    enum perf_call_graph_mode record_mode;
    u32         dump_size;
    enum chain_mode     mode;
    u16         max_stack;
    u32         print_limit;
    double          min_percent;
    sort_chain_func_t   sort;
    enum chain_order    order;
    bool            order_set;
    enum chain_key      key;
    bool            branch_callstack;
    enum chain_value    value;
};

extern struct callchain_param callchain_param;
extern struct callchain_param callchain_param_default;

struct callchain_list {
    u64         ip;
    struct map_symbol   ms;
    struct /* for TUI */ {
        bool        unfolded;
        bool        has_children;
    };
    u64         branch_count;
    u64         predicted_count;
    u64         abort_count;
    u64         cycles_count;
    u64         iter_count;
    u64         iter_cycles;
    struct branch_type_stat brtype_stat;
    const char      *srcline;
    struct list_head    list;
};

/*
 * A callchain cursor is a single linked list that
 * let one feed a callchain progressively.
 * It keeps persistent allocated entries to minimize
 * allocations.
 */
struct callchain_cursor_node {
    u64             ip;
    struct map          *map;
    struct symbol           *sym;
    const char          *srcline;
    bool                branch;
    struct branch_flags     branch_flags;
    u64             branch_from;
    int             nr_loop_iter;
    u64             iter_cycles;
    struct callchain_cursor_node    *next;
};

struct callchain_cursor {
    u64             nr;
    struct callchain_cursor_node    *first;
    struct callchain_cursor_node    **last;
    u64             pos;
    struct callchain_cursor_node    *curr;
};

extern __thread struct callchain_cursor callchain_cursor;

static inline void callchain_init(struct callchain_root *root)
{
    INIT_LIST_HEAD(&root->node.val);
    INIT_LIST_HEAD(&root->node.parent_val);

    root->node.parent = NULL;
    root->node.hit = 0;
    root->node.children_hit = 0;
    root->node.rb_root_in = RB_ROOT;
    root->max_depth = 0;
}

static inline u64 callchain_cumul_hits(struct callchain_node *node)
{
    return node->hit + node->children_hit;
}

static inline unsigned callchain_cumul_counts(struct callchain_node *node)
{
    return node->count + node->children_count;
}

int callchain_register_param(struct callchain_param *param);
int callchain_append(struct callchain_root *root,
             struct callchain_cursor *cursor,
             u64 period);

int callchain_merge(struct callchain_cursor *cursor,
            struct callchain_root *dst, struct callchain_root *src);

/*
 * Initialize a cursor before adding entries inside, but keep
 * the previously allocated entries as a cache.
 */
static inline void callchain_cursor_reset(struct callchain_cursor *cursor)
{
    struct callchain_cursor_node *node;

    cursor->nr = 0;
    cursor->last = &cursor->first;

    for (node = cursor->first; node != NULL; node = node->next)
        map__zput(node->map);
}

int callchain_cursor_append(struct callchain_cursor *cursor, u64 ip,
                struct map *map, struct symbol *sym,
                bool branch, struct branch_flags *flags,
                int nr_loop_iter, u64 iter_cycles, u64 branch_from,
                const char *srcline);

/* Close a cursor writing session. Initialize for the reader */
static inline void callchain_cursor_commit(struct callchain_cursor *cursor)
{
    cursor->curr = cursor->first;
    cursor->pos = 0;
}

/* Cursor reading iteration helpers */
static inline struct callchain_cursor_node *
callchain_cursor_current(struct callchain_cursor *cursor)
{
    if (cursor->pos == cursor->nr)
        return NULL;

    return cursor->curr;
}

static inline void callchain_cursor_advance(struct callchain_cursor *cursor)
{
    cursor->curr = cursor->curr->next;
    cursor->pos++;
}

int callchain_cursor__copy(struct callchain_cursor *dst,
               struct callchain_cursor *src);

struct option;
struct hist_entry;

int record_parse_callchain_opt(const struct option *opt, const char *arg, int unset);
int record_callchain_opt(const struct option *opt, const char *arg, int unset);

struct record_opts;

int record_opts__parse_callchain(struct record_opts *record,
                 struct callchain_param *callchain,
                 const char *arg, bool unset);

int sample__resolve_callchain(struct perf_sample *sample,
                  struct callchain_cursor *cursor, struct symbol **parent,
                  struct perf_evsel *evsel, struct addr_location *al,
                  int max_stack);
int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *sample);
int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
            bool hide_unresolved);

extern const char record_callchain_help[];
int parse_callchain_record(const char *arg, struct callchain_param *param);
int parse_callchain_record_opt(const char *arg, struct callchain_param *param);
int parse_callchain_report_opt(const char *arg);
int parse_callchain_top_opt(const char *arg);
int perf_callchain_config(const char *var, const char *value);

static inline void callchain_cursor_snapshot(struct callchain_cursor *dest,
                         struct callchain_cursor *src)
{
    *dest = *src;

    dest->first = src->curr;
    dest->nr -= src->pos;
}

#ifdef HAVE_SKIP_CALLCHAIN_IDX
int arch_skip_callchain_idx(struct thread *thread, struct ip_callchain *chain);
#else
static inline int arch_skip_callchain_idx(struct thread *thread __maybe_unused,
            struct ip_callchain *chain __maybe_unused)
{
    return -1;
}
#endif

char *callchain_list__sym_name(struct callchain_list *cl,
                   char *bf, size_t bfsize, bool show_dso);
char *callchain_node__scnprintf_value(struct callchain_node *node,
                      char *bf, size_t bfsize, u64 total);
int callchain_node__fprintf_value(struct callchain_node *node,
                  FILE *fp, u64 total);

int callchain_list_counts__printf_value(struct callchain_list *clist,
                    FILE *fp, char *bf, int bfsize);

void free_callchain(struct callchain_root *root);
void decay_callchain(struct callchain_root *root);
int callchain_node__make_parent_list(struct callchain_node *node);

int callchain_branch_counts(struct callchain_root *root,
                u64 *branch_count, u64 *predicted_count,
                u64 *abort_count, u64 *cycles_count);

#endif  /* __PERF_CALLCHAIN_H */