Re: [PATCH perf/core v5 04/15] perf probe: Add --cache option to cache the probe definitions

From: Namhyung Kim
Date: Wed Apr 27 2016 - 22:12:49 EST


On Thu, Apr 28, 2016 at 03:37:42AM +0900, Masami Hiramatsu wrote:
> From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
>
> Add --cache option to cache the probe definitions. This
> just saves the result of the dwarf analysis to probe cache.
>
> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> ---
> Changes in v5:
> - Move probe_cache* definitions. (code cleanup)
>
> Changes in v4:
> - Remove cache saving failure message.
> ---

[snip]
> +static int probe_cache__load(struct probe_cache *pcache)
> +{
> + struct probe_cache_entry *entry = NULL;
> + char buf[MAX_CMDLEN], *p;
> + int ret = 0;
> + FILE *fp;
> +
> + fp = fdopen(dup(pcache->fd), "r");
> + while (!feof(fp)) {
> + if (!fgets(buf, MAX_CMDLEN, fp))
> + break;
> + p = strchr(buf, '\n');
> + if (p)
> + *p = '\0';
> + if (buf[0] == '#') { /* #perf_probe_event */
> + entry = probe_cache_entry__new(NULL);

The probe_cache_entry__new() can fail.

Thanks,
Namhyung


> + entry->spev = strdup(buf + 1);
> + ret = parse_perf_probe_command(buf + 1, &entry->pev);
> + if (!entry->spev || ret < 0) {
> + probe_cache_entry__delete(entry);
> + goto out;
> + }
> + list_add_tail(&entry->list, &pcache->list);
> + } else { /* trace_probe_event */
> + if (!entry) {
> + ret = -EINVAL;
> + goto out;
> + }
> + strlist__add(entry->tevlist, buf);
> + }
> + }
> +out:
> + fclose(fp);
> + return ret;
> +}