LXR linux/tools/perf/util/comm.c

   1#include "comm.h"
   2#include "util.h"
   3#include <stdlib.h>
   4#include <stdio.h>
   5
   6struct comm_str {
   7        char *str;
   8        struct rb_node rb_node;
   9        int ref;
  10};
  11
  12/* Should perhaps be moved to struct machine */
  13static struct rb_root comm_str_root;
  14
  15static void comm_str__get(struct comm_str *cs)
  16{
  17        cs->ref++;
  18}
  19
  20static void comm_str__put(struct comm_str *cs)
  21{
  22        if (!--cs->ref) {
  23                rb_erase(&cs->rb_node, &comm_str_root);
  24                free(cs->str);
  25                free(cs);
  26        }
  27}
  28
  29static struct comm_str *comm_str__alloc(const char *str)
  30{
  31        struct comm_str *cs;
  32
  33        cs = zalloc(sizeof(*cs));
  34        if (!cs)
  35                return NULL;
  36
  37        cs->str = strdup(str);
  38        if (!cs->str) {
  39                free(cs);
  40                return NULL;
  41        }
  42
  43        return cs;
  44}
  45
  46static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
  47{
  48        struct rb_node **p = &root->rb_node;
  49        struct rb_node *parent = NULL;
  50        struct comm_str *iter, *new;
  51        int cmp;
  52
  53        while (*p != NULL) {
  54                parent = *p;
  55                iter = rb_entry(parent, struct comm_str, rb_node);
  56
  57                cmp = strcmp(str, iter->str);
  58                if (!cmp)
  59                        return iter;
  60
  61                if (cmp < 0)
  62                        p = &(*p)->rb_left;
  63                else
  64                        p = &(*p)->rb_right;
  65        }
  66
  67        new = comm_str__alloc(str);
  68        if (!new)
  69                return NULL;
  70
  71        rb_link_node(&new->rb_node, parent, p);
  72        rb_insert_color(&new->rb_node, root);
  73
  74        return new;
  75}
  76
  77struct comm *comm__new(const char *str, u64 timestamp)
  78{
  79        struct comm *comm = zalloc(sizeof(*comm));
  80
  81        if (!comm)
  82                return NULL;
  83
  84        comm->start = timestamp;
  85
  86        comm->comm_str = comm_str__findnew(str, &comm_str_root);
  87        if (!comm->comm_str) {
  88                free(comm);
  89                return NULL;
  90        }
  91
  92        comm_str__get(comm->comm_str);
  93
  94        return comm;
  95}
  96
  97void comm__override(struct comm *comm, const char *str, u64 timestamp)
  98{
  99        struct comm_str *old = comm->comm_str;
 100
 101        comm->comm_str = comm_str__findnew(str, &comm_str_root);
 102        if (!comm->comm_str) {
 103                comm->comm_str = old;
 104                return;
 105        }
 106
 107        comm->start = timestamp;
 108        comm_str__get(comm->comm_str);
 109        comm_str__put(old);
 110}
 111
 112void comm__free(struct comm *comm)
 113{
 114        comm_str__put(comm->comm_str);
 115        free(comm);
 116}
 117
 118const char *comm__str(const struct comm *comm)
 119{
 120        return comm->comm_str->str;
 121}
 122