perf probe: Check symbols in symtab/kallsyms

Check symbols in symtab/kallsyms when no debuginfo
is available.

e.g.

 # perf probe test
  Fatal: Kernel symbol 'test' not found - probe not added.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091215153239.17436.55034.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 22 insertions, 10 deletions

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 0584b7a0ed36..6b0e4cf322d8 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -59,6 +59,7 @@ static struct {
         struct strlist *dellist;
         struct symbol_conf conf;
         struct perf_session *psession;
+        struct map *kmap;
 } session;
 
 
@@ -115,22 +116,26 @@ static int opt_del_probe_event(const struct option *opt __used,
         return 0;
 }
 
+/* Currently just checking function name from symbol map */
+static void evaluate_probe_point(struct probe_point *pp)
+{
+        struct symbol *sym;
+        sym = map__find_symbol_by_name(session.kmap, pp->function,
+                                       session.psession, NULL);
+        if (!sym)
+                die("Kernel symbol \'%s\' not found - probe not added.",
+                    pp->function);
+}
+
 #ifndef NO_LIBDWARF
 static int open_vmlinux(void)
 {
-        struct map *kmap;
-        kmap = map_groups__find_by_name(&session.psession->kmaps,
-                                        MAP__FUNCTION, "[kernel.kallsyms]");
-        if (!kmap) {
-                pr_debug("Could not find kernel map.\n");
-                return -ENOENT;
-        }
-        if (map__load(kmap, session.psession, NULL) < 0) {
+        if (map__load(session.kmap, session.psession, NULL) < 0) {
                 pr_debug("Failed to load kernel map.\n");
                 return -EINVAL;
         }
-        pr_debug("Try to open %s\n", kmap->dso->long_name);
-        return open(kmap->dso->long_name, O_RDONLY);
+        pr_debug("Try to open %s\n", session.kmap->dso->long_name);
+        return open(session.kmap->dso->long_name, O_RDONLY);
 }
 #endif
 
@@ -219,6 +224,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
         }
 
         /* Initialize symbol maps for vmlinux */
+        session.conf.sort_by_name = true;
         if (session.conf.vmlinux_name == NULL)
                 session.conf.try_vmlinux_path = true;
         if (symbol__init(&session.conf) < 0)
@@ -227,6 +233,11 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
                                              &session.conf);
         if (session.psession == NULL)
                 die("Failed to init perf_session.");
+        session.kmap = map_groups__find_by_name(&session.psession->kmaps,
+                                                MAP__FUNCTION,
+                                                "[kernel.kallsyms]");
+        if (!session.kmap)
+                die("Could not find kernel map.\n");
 
         if (session.need_dwarf)
 #ifdef NO_LIBDWARF
@@ -277,6 +288,7 @@ end_dwarf:
                 if (pp->found)  /* This probe is already found. */
                         continue;
 
+                evaluate_probe_point(pp);
                 ret = synthesize_trace_kprobe_event(pp);
                 if (ret == -E2BIG)
                         die("probe point definition becomes too long.");