2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-28 15:13:55 +08:00
linux-next/tools/perf/util/comm.c
Frederic Weisbecker 3178f58b98 perf tools: Do proper comm override error handling
The comm overriding API ignores memory allocation failures by silently
keeping the previous and out of date comm.

As a result, the user may get buggy events without ever being notified
about the problem and its source.

Lets start to fix this by propagating the error from the API. Not all
callers may be doing proper error handling on comm set yet but this is
the first step toward it.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1389713836-13375-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-01-16 16:44:39 -03:00

123 lines
2.0 KiB
C

#include "comm.h"
#include "util.h"
#include <stdlib.h>
#include <stdio.h>
struct comm_str {
char *str;
struct rb_node rb_node;
int ref;
};
/* Should perhaps be moved to struct machine */
static struct rb_root comm_str_root;
static void comm_str__get(struct comm_str *cs)
{
cs->ref++;
}
static void comm_str__put(struct comm_str *cs)
{
if (!--cs->ref) {
rb_erase(&cs->rb_node, &comm_str_root);
zfree(&cs->str);
free(cs);
}
}
static struct comm_str *comm_str__alloc(const char *str)
{
struct comm_str *cs;
cs = zalloc(sizeof(*cs));
if (!cs)
return NULL;
cs->str = strdup(str);
if (!cs->str) {
free(cs);
return NULL;
}
return cs;
}
static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
struct comm_str *iter, *new;
int cmp;
while (*p != NULL) {
parent = *p;
iter = rb_entry(parent, struct comm_str, rb_node);
cmp = strcmp(str, iter->str);
if (!cmp)
return iter;
if (cmp < 0)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
new = comm_str__alloc(str);
if (!new)
return NULL;
rb_link_node(&new->rb_node, parent, p);
rb_insert_color(&new->rb_node, root);
return new;
}
struct comm *comm__new(const char *str, u64 timestamp)
{
struct comm *comm = zalloc(sizeof(*comm));
if (!comm)
return NULL;
comm->start = timestamp;
comm->comm_str = comm_str__findnew(str, &comm_str_root);
if (!comm->comm_str) {
free(comm);
return NULL;
}
comm_str__get(comm->comm_str);
return comm;
}
int comm__override(struct comm *comm, const char *str, u64 timestamp)
{
struct comm_str *new, *old = comm->comm_str;
new = comm_str__findnew(str, &comm_str_root);
if (!new)
return -ENOMEM;
comm_str__get(new);
comm_str__put(old);
comm->comm_str = new;
comm->start = timestamp;
return 0;
}
void comm__free(struct comm *comm)
{
comm_str__put(comm->comm_str);
free(comm);
}
const char *comm__str(const struct comm *comm)
{
return comm->comm_str->str;
}