perf probe: Factor out the ftrace README scanning

Simplify and separate out the ftrace README scanning logic into a
separate helper. This is used subsequently to scan for all patterns of
interest and to cache the result.

Since we are only interested in availability of probe argument type x,
we will only scan for that.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/6dc30edc747ba82a236593be6cf3a046fa9453b5.1488961018.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Naveen N. Rao 2017-03-08 13:56:08 +05:30 committed by Arnaldo Carvalho de Melo
parent 292c4a8f98
commit 3da3ea7a8e
1 changed files with 39 additions and 35 deletions

View File

@ -877,35 +877,31 @@ int probe_cache__show_all_caches(struct strfilter *filter)
return 0; return 0;
} }
static struct { enum ftrace_readme {
const char *pattern; FTRACE_README_PROBE_TYPE_X = 0,
bool avail; FTRACE_README_END,
bool checked;
} probe_type_table[] = {
#define DEFINE_TYPE(idx, pat, def_avail) \
[idx] = {.pattern = pat, .avail = (def_avail)}
DEFINE_TYPE(PROBE_TYPE_U, "* u8/16/32/64,*", true),
DEFINE_TYPE(PROBE_TYPE_S, "* s8/16/32/64,*", true),
DEFINE_TYPE(PROBE_TYPE_X, "* x8/16/32/64,*", false),
DEFINE_TYPE(PROBE_TYPE_STRING, "* string,*", true),
DEFINE_TYPE(PROBE_TYPE_BITFIELD,
"* b<bit-width>@<bit-offset>/<container-size>", true),
}; };
bool probe_type_is_available(enum probe_type type) static struct {
const char *pattern;
bool avail;
} ftrace_readme_table[] = {
#define DEFINE_TYPE(idx, pat) \
[idx] = {.pattern = pat, .avail = false}
DEFINE_TYPE(FTRACE_README_PROBE_TYPE_X, "*type: * x8/16/32/64,*"),
};
static bool scan_ftrace_readme(enum ftrace_readme type)
{ {
int fd;
FILE *fp; FILE *fp;
char *buf = NULL; char *buf = NULL;
size_t len = 0; size_t len = 0;
bool target_line = false; bool ret = false;
bool ret = probe_type_table[type].avail; static bool scanned = false;
int fd;
if (type >= PROBE_TYPE_END) if (scanned)
return false; goto result;
/* We don't have to check the type which supported by default */
if (ret || probe_type_table[type].checked)
return ret;
fd = open_trace_file("README", false); fd = open_trace_file("README", false);
if (fd < 0) if (fd < 0)
@ -917,21 +913,29 @@ bool probe_type_is_available(enum probe_type type)
return ret; return ret;
} }
while (getline(&buf, &len, fp) > 0 && !ret) { while (getline(&buf, &len, fp) > 0)
if (!target_line) { for (enum ftrace_readme i = 0; i < FTRACE_README_END; i++)
target_line = !!strstr(buf, " type: "); if (!ftrace_readme_table[i].avail)
if (!target_line) ftrace_readme_table[i].avail =
continue; strglobmatch(buf, ftrace_readme_table[i].pattern);
} else if (strstr(buf, "\t ") != buf) scanned = true;
break;
ret = strglobmatch(buf, probe_type_table[type].pattern);
}
/* Cache the result */
probe_type_table[type].checked = true;
probe_type_table[type].avail = ret;
fclose(fp); fclose(fp);
free(buf); free(buf);
return ret; result:
if (type >= FTRACE_README_END)
return false;
return ftrace_readme_table[type].avail;
}
bool probe_type_is_available(enum probe_type type)
{
if (type >= PROBE_TYPE_END)
return false;
else if (type == PROBE_TYPE_X)
return scan_ftrace_readme(FTRACE_README_PROBE_TYPE_X);
return true;
} }