Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf improvements and fixes from Arnaldo Carvalho de Melo:

Infrastructure changes:

 * Improve callchain processing by removing unnecessary work. (Frederic Weisbecker)

 * Fix comm override error handling (Frederic Weisbecker)

 * Improve 'perf probe' exit path, release resources (Masami Hiramatsu)

 * Improve libtraceevent plugins exit path, allowing the registering of
   an unregister handler to be called at exit time (Namhyung Kim)

 * Add an alias to the build test makefile (make -C tools/perf build-test)
   (Namhyung Kim)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

23 files changed, 389 insertions, 112 deletions

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 2ce565a73dd5..1587ea392ad6 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -5561,6 +5561,52 @@ int pevent_register_print_function(struct pevent *pevent,
 }
 
 /**
+ * pevent_unregister_print_function - unregister a helper function
+ * @pevent: the handle to the pevent
+ * @func: the function to process the helper function
+ * @name: the name of the helper function
+ *
+ * This function removes existing print handler for function @name.
+ *
+ * Returns 0 if the handler was removed successully, -1 otherwise.
+ */
+int pevent_unregister_print_function(struct pevent *pevent,
+                                     pevent_func_handler func, char *name)
+{
+        struct pevent_function_handler *func_handle;
+
+        func_handle = find_func_handler(pevent, name);
+        if (func_handle && func_handle->func == func) {
+                remove_func_handler(pevent, name);
+                return 0;
+        }
+        return -1;
+}
+
+static struct event_format *pevent_search_event(struct pevent *pevent, int id,
+                                                const char *sys_name,
+                                                const char *event_name)
+{
+        struct event_format *event;
+
+        if (id >= 0) {
+                /* search by id */
+                event = pevent_find_event(pevent, id);
+                if (!event)
+                        return NULL;
+                if (event_name && (strcmp(event_name, event->name) != 0))
+                        return NULL;
+                if (sys_name && (strcmp(sys_name, event->system) != 0))
+                        return NULL;
+        } else {
+                event = pevent_find_event_by_name(pevent, sys_name, event_name);
+                if (!event)
+                        return NULL;
+        }
+        return event;
+}
+
+/**
  * pevent_register_event_handler - register a way to parse an event
  * @pevent: the handle to the pevent
  * @id: the id of the event to register
@@ -5584,20 +5630,9 @@ int pevent_register_event_handler(struct pevent *pevent, int id,
         struct event_format *event;
         struct event_handler *handle;
 
-        if (id >= 0) {
-                /* search by id */
-                event = pevent_find_event(pevent, id);
-                if (!event)
-                        goto not_found;
-                if (event_name && (strcmp(event_name, event->name) != 0))
-                        goto not_found;
-                if (sys_name && (strcmp(sys_name, event->system) != 0))
-                        goto not_found;
-        } else {
-                event = pevent_find_event_by_name(pevent, sys_name, event_name);
-                if (!event)
-                        goto not_found;
-        }
+        event = pevent_search_event(pevent, id, sys_name, event_name);
+        if (event == NULL)
+                goto not_found;
 
         pr_stat("overriding event (%d) %s:%s with new print handler",
                 event->id, event->system, event->name);
@@ -5637,6 +5672,79 @@ int pevent_register_event_handler(struct pevent *pevent, int id,
         return -1;
 }
 
+static int handle_matches(struct event_handler *handler, int id,
+                          const char *sys_name, const char *event_name,
+                          pevent_event_handler_func func, void *context)
+{
+        if (id >= 0 && id != handler->id)
+                return 0;
+
+        if (event_name && (strcmp(event_name, handler->event_name) != 0))
+                return 0;
+
+        if (sys_name && (strcmp(sys_name, handler->sys_name) != 0))
+                return 0;
+
+        if (func != handler->func || context != handler->context)
+                return 0;
+
+        return 1;
+}
+
+/**
+ * pevent_unregister_event_handler - unregister an existing event handler
+ * @pevent: the handle to the pevent
+ * @id: the id of the event to unregister
+ * @sys_name: the system name the handler belongs to
+ * @event_name: the name of the event handler
+ * @func: the function to call to parse the event information
+ * @context: the data to be passed to @func
+ *
+ * This function removes existing event handler (parser).
+ *
+ * If @id is >= 0, then it is used to find the event.
+ * else @sys_name and @event_name are used.
+ *
+ * Returns 0 if handler was removed successfully, -1 if event was not found.
+ */
+int pevent_unregister_event_handler(struct pevent *pevent, int id,
+                                    const char *sys_name, const char *event_name,
+                                    pevent_event_handler_func func, void *context)
+{
+        struct event_format *event;
+        struct event_handler *handle;
+        struct event_handler **next;
+
+        event = pevent_search_event(pevent, id, sys_name, event_name);
+        if (event == NULL)
+                goto not_found;
+
+        if (event->handler == func && event->context == context) {
+                pr_stat("removing override handler for event (%d) %s:%s. Going back to default handler.",
+                        event->id, event->system, event->name);
+
+                event->handler = NULL;
+                event->context = NULL;
+                return 0;
+        }
+
+not_found:
+        for (next = &pevent->handlers; *next; next = &(*next)->next) {
+                handle = *next;
+                if (handle_matches(handle, id, sys_name, event_name,
+                                   func, context))
+                        break;
+        }
+
+        if (!(*next))
+                return -1;
+
+        *next = handle->next;
+        free_handler(handle);
+
+        return 0;
+}
+
 /**
  * pevent_alloc - create a pevent handle
  */
diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h
index a3beca56cb35..791c539374c7 100644
--- a/tools/lib/traceevent/event-parse.h
+++ b/tools/lib/traceevent/event-parse.h
@@ -624,10 +624,15 @@ int pevent_print_func_field(struct trace_seq *s, const char *fmt,
 int pevent_register_event_handler(struct pevent *pevent, int id,
                                   const char *sys_name, const char *event_name,
                                   pevent_event_handler_func func, void *context);
+int pevent_unregister_event_handler(struct pevent *pevent, int id,
+                                    const char *sys_name, const char *event_name,
+                                    pevent_event_handler_func func, void *context);
 int pevent_register_print_function(struct pevent *pevent,
                                    pevent_func_handler func,
                                    enum pevent_func_arg_type ret_type,
                                    char *name, ...);
+int pevent_unregister_print_function(struct pevent *pevent,
+                                     pevent_func_handler func, char *name);
 
 struct format_field *pevent_find_common_field(struct event_format *event, const char *name);
 struct format_field *pevent_find_field(struct event_format *event, const char *name);
diff --git a/tools/lib/traceevent/plugin_cfg80211.c b/tools/lib/traceevent/plugin_cfg80211.c
index 57e98221db20..c066b25905f8 100644
--- a/tools/lib/traceevent/plugin_cfg80211.c
+++ b/tools/lib/traceevent/plugin_cfg80211.c
@@ -22,3 +22,9 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                        PEVENT_FUNC_ARG_VOID);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_print_function(pevent, process___le16_to_cpup,
+                                         "__le16_to_cpup");
+}
diff --git a/tools/lib/traceevent/plugin_function.c b/tools/lib/traceevent/plugin_function.c
index 39461485f9a7..80ba4ff1fe84 100644
--- a/tools/lib/traceevent/plugin_function.c
+++ b/tools/lib/traceevent/plugin_function.c
@@ -148,6 +148,9 @@ void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
 {
         int i, x;
 
+        pevent_unregister_event_handler(pevent, -1, "ftrace", "function",
+                                        function_handler, NULL);
+
         for (i = 0; i <= cpus; i++) {
                 for (x = 0; x < fstack[i].size && fstack[i].stack[x]; x++)
                         free(fstack[i].stack[x]);
diff --git a/tools/lib/traceevent/plugin_hrtimer.c b/tools/lib/traceevent/plugin_hrtimer.c
index 0b0ebf30aa44..12bf14cc1152 100644
--- a/tools/lib/traceevent/plugin_hrtimer.c
+++ b/tools/lib/traceevent/plugin_hrtimer.c
@@ -76,3 +76,13 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                       timer_start_handler, NULL);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_event_handler(pevent, -1,
+                                        "timer", "hrtimer_expire_entry",
+                                        timer_expire_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "timer", "hrtimer_start",
+                                        timer_start_handler, NULL);
+}
diff --git a/tools/lib/traceevent/plugin_jbd2.c b/tools/lib/traceevent/plugin_jbd2.c
index 2f93f81f0bac..0db714c721be 100644
--- a/tools/lib/traceevent/plugin_jbd2.c
+++ b/tools/lib/traceevent/plugin_jbd2.c
@@ -66,3 +66,12 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                        PEVENT_FUNC_ARG_VOID);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_print_function(pevent, process_jbd2_dev_to_name,
+                                         "jbd2_dev_to_name");
+
+        pevent_unregister_print_function(pevent, process_jiffies_to_msecs,
+                                         "jiffies_to_msecs");
+}
diff --git a/tools/lib/traceevent/plugin_kmem.c b/tools/lib/traceevent/plugin_kmem.c
index 7115c8037ea8..70650ff48d78 100644
--- a/tools/lib/traceevent/plugin_kmem.c
+++ b/tools/lib/traceevent/plugin_kmem.c
@@ -70,3 +70,25 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                       call_site_handler, NULL);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_event_handler(pevent, -1, "kmem", "kfree",
+                                        call_site_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kmem", "kmalloc",
+                                        call_site_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kmem", "kmalloc_node",
+                                        call_site_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kmem", "kmem_cache_alloc",
+                                        call_site_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kmem",
+                                        "kmem_cache_alloc_node",
+                                        call_site_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kmem", "kmem_cache_free",
+                                        call_site_handler, NULL);
+}
diff --git a/tools/lib/traceevent/plugin_kvm.c b/tools/lib/traceevent/plugin_kvm.c
index a0e282c6b967..9e0e8c61b43b 100644
--- a/tools/lib/traceevent/plugin_kvm.c
+++ b/tools/lib/traceevent/plugin_kvm.c
@@ -434,3 +434,32 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                        PEVENT_FUNC_ARG_VOID);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_event_handler(pevent, -1, "kvm", "kvm_exit",
+                                        kvm_exit_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kvm", "kvm_emulate_insn",
+                                        kvm_emulate_insn_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kvmmmu", "kvm_mmu_get_page",
+                                        kvm_mmu_get_page_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kvmmmu", "kvm_mmu_sync_page",
+                                        kvm_mmu_print_role, NULL);
+
+        pevent_unregister_event_handler(pevent, -1,
+                                        "kvmmmu", "kvm_mmu_unsync_page",
+                                        kvm_mmu_print_role, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kvmmmu", "kvm_mmu_zap_page",
+                                        kvm_mmu_print_role, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "kvmmmu",
+                        "kvm_mmu_prepare_zap_page", kvm_mmu_print_role,
+                        NULL);
+
+        pevent_unregister_print_function(pevent, process_is_writable_pte,
+                                         "is_writable_pte");
+}
diff --git a/tools/lib/traceevent/plugin_mac80211.c b/tools/lib/traceevent/plugin_mac80211.c
index 558a3b91c046..7e15a0f1c2fd 100644
--- a/tools/lib/traceevent/plugin_mac80211.c
+++ b/tools/lib/traceevent/plugin_mac80211.c
@@ -93,3 +93,10 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                       drv_bss_info_changed, NULL);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_event_handler(pevent, -1, "mac80211",
+                                        "drv_bss_info_changed",
+                                        drv_bss_info_changed, NULL);
+}
diff --git a/tools/lib/traceevent/plugin_sched_switch.c b/tools/lib/traceevent/plugin_sched_switch.c
index fea3724aa24f..f1ce60065258 100644
--- a/tools/lib/traceevent/plugin_sched_switch.c
+++ b/tools/lib/traceevent/plugin_sched_switch.c
@@ -146,3 +146,15 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                       sched_wakeup_handler, NULL);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_event_handler(pevent, -1, "sched", "sched_switch",
+                                        sched_switch_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "sched", "sched_wakeup",
+                                        sched_wakeup_handler, NULL);
+
+        pevent_unregister_event_handler(pevent, -1, "sched", "sched_wakeup_new",
+                                        sched_wakeup_handler, NULL);
+}
diff --git a/tools/lib/traceevent/plugin_scsi.c b/tools/lib/traceevent/plugin_scsi.c
index 7ef16cc96562..eda326fc8620 100644
--- a/tools/lib/traceevent/plugin_scsi.c
+++ b/tools/lib/traceevent/plugin_scsi.c
@@ -421,3 +421,9 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                        PEVENT_FUNC_ARG_VOID);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_print_function(pevent, process_scsi_trace_parse_cdb,
+                                         "scsi_trace_parse_cdb");
+}
diff --git a/tools/lib/traceevent/plugin_xen.c b/tools/lib/traceevent/plugin_xen.c
index e7794298f3a9..3a413eaada68 100644
--- a/tools/lib/traceevent/plugin_xen.c
+++ b/tools/lib/traceevent/plugin_xen.c
@@ -128,3 +128,9 @@ int PEVENT_PLUGIN_LOADER(struct pevent *pevent)
                                        PEVENT_FUNC_ARG_VOID);
         return 0;
 }
+
+void PEVENT_PLUGIN_UNLOADER(struct pevent *pevent)
+{
+        pevent_unregister_print_function(pevent, process_xen_hypercall_name,
+                                         "xen_hypercall_name");
+}
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index eefb9fb0c02f..cb2e5868c8e8 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -75,6 +75,12 @@ clean:
         $(make)
 
 #
+# The build-test target is not really parallel, don't print the jobs info:
+#
+build-test:
+        @$(MAKE) -f tests/make --no-print-directory
+
+#
 # All other targets get passed through:
 #
 %:
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 43ff33d0007b..78948882e3de 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -59,7 +59,7 @@ static struct {
         struct perf_probe_event events[MAX_PROBES];
         struct strlist *dellist;
         struct line_range line_range;
-        const char *target;
+        char *target;
         int max_probe_points;
         struct strfilter *filter;
 } params;
@@ -98,7 +98,10 @@ static int set_target(const char *ptr)
          * short module name.
          */
         if (!params.target && ptr && *ptr == '/') {
-                params.target = ptr;
+                params.target = strdup(ptr);
+                if (!params.target)
+                        return -ENOMEM;
+
                 found = 1;
                 buf = ptr + (strlen(ptr) - 3);
 
@@ -116,6 +119,9 @@ static int parse_probe_event_argv(int argc, const char **argv)
         char *buf;
 
         found_target = set_target(argv[0]);
+        if (found_target < 0)
+                return found_target;
+
         if (found_target && argc == 1)
                 return 0;
 
@@ -217,7 +223,6 @@ static int opt_show_lines(const struct option *opt __maybe_unused,
 
         params.show_lines = true;
         ret = parse_line_range_desc(str, &params.line_range);
-        INIT_LIST_HEAD(&params.line_range.line_list);
 
         return ret;
 }
@@ -263,7 +268,28 @@ static int opt_set_filter(const struct option *opt __maybe_unused,
         return 0;
 }
 
-int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
+static void init_params(void)
+{
+        line_range__init(&params.line_range);
+}
+
+static void cleanup_params(void)
+{
+        int i;
+
+        for (i = 0; i < params.nevents; i++)
+                clear_perf_probe_event(params.events + i);
+        if (params.dellist)
+                strlist__delete(params.dellist);
+        line_range__clear(&params.line_range);
+        free(params.target);
+        if (params.filter)
+                strfilter__delete(params.filter);
+        memset(&params, 0, sizeof(params));
+}
+
+static int
+__cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
 {
         const char * const probe_usage[] = {
                 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
@@ -417,6 +443,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
                 ret = show_available_funcs(params.target, params.filter,
                                         params.uprobes);
                 strfilter__delete(params.filter);
+                params.filter = NULL;
                 if (ret < 0)
                         pr_err("  Error: Failed to show functions."
                                " (%d)\n", ret);
@@ -456,6 +483,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
                                           params.filter,
                                           params.show_ext_vars);
                 strfilter__delete(params.filter);
+                params.filter = NULL;
                 if (ret < 0)
                         pr_err("  Error: Failed to show vars. (%d)\n", ret);
                 return ret;
@@ -464,7 +492,6 @@ int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
 
         if (params.dellist) {
                 ret = del_perf_probe_events(params.dellist);
-                strlist__delete(params.dellist);
                 if (ret < 0) {
                         pr_err("  Error: Failed to delete events. (%d)\n", ret);
                         return ret;
@@ -483,3 +510,14 @@ int cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
         }
         return 0;
 }
+
+int cmd_probe(int argc, const char **argv, const char *prefix)
+{
+        int ret;
+
+        init_params();
+        ret = __cmd_probe(argc, argv, prefix);
+        cleanup_params();
+
+        return ret;
+}
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 9eb4f57f8663..8d9db454f1a9 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -15,6 +15,8 @@
 #include <errno.h>
 #include <math.h>
 
+#include "asm/bug.h"
+
 #include "hist.h"
 #include "util.h"
 #include "sort.h"
@@ -358,19 +360,14 @@ append_chain_children(struct callchain_node *root,
         /* lookup in childrens */
         while (*p) {
                 s64 ret;
-                struct callchain_list *cnode;
 
                 parent = *p;
                 rnode = rb_entry(parent, struct callchain_node, rb_node_in);
-                cnode = list_first_entry(&rnode->val, struct callchain_list,
-                                         list);
 
-                /* just check first entry */
-                ret = match_chain(node, cnode);
-                if (ret == 0) {
-                        append_chain(rnode, cursor, period);
+                /* If at least first entry matches, rely to children */
+                ret = append_chain(rnode, cursor, period);
+                if (ret == 0)
                         goto inc_children_hit;
-                }
 
                 if (ret < 0)
                         p = &parent->rb_left;
@@ -391,11 +388,11 @@ append_chain(struct callchain_node *root,
              struct callchain_cursor *cursor,
              u64 period)
 {
-        struct callchain_cursor_node *curr_snap = cursor->curr;
         struct callchain_list *cnode;
         u64 start = cursor->pos;
         bool found = false;
         u64 matches;
+        int cmp = 0;
 
         /*
          * Lookup in the current node
@@ -410,7 +407,8 @@ append_chain(struct callchain_node *root,
                 if (!node)
                         break;
 
-                if (match_chain(node, cnode) != 0)
+                cmp = match_chain(node, cnode);
+                if (cmp)
                         break;
 
                 found = true;
@@ -420,9 +418,8 @@ append_chain(struct callchain_node *root,
 
         /* matches not, relay no the parent */
         if (!found) {
-                cursor->curr = curr_snap;
-                cursor->pos = start;
-                return -1;
+                WARN_ONCE(!cmp, "Chain comparison error\n");
+                return cmp;
         }
 
         matches = cursor->pos - start;
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 67d1e404c0cb..f9e777629e21 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -94,19 +94,20 @@ struct comm *comm__new(const char *str, u64 timestamp)
         return comm;
 }
 
-void comm__override(struct comm *comm, const char *str, u64 timestamp)
+int comm__override(struct comm *comm, const char *str, u64 timestamp)
 {
-        struct comm_str *old = comm->comm_str;
+        struct comm_str *new, *old = comm->comm_str;
 
-        comm->comm_str = comm_str__findnew(str, &comm_str_root);
-        if (!comm->comm_str) {
-                comm->comm_str = old;
-                return;
-        }
+        new = comm_str__findnew(str, &comm_str_root);
+        if (!new)
+                return -ENOMEM;
 
-        comm->start = timestamp;
-        comm_str__get(comm->comm_str);
+        comm_str__get(new);
         comm_str__put(old);
+        comm->comm_str = new;
+        comm->start = timestamp;
+
+        return 0;
 }
 
 void comm__free(struct comm *comm)
diff --git a/tools/perf/util/comm.h b/tools/perf/util/comm.h
index 7a86e5656710..fac5bd51befc 100644
--- a/tools/perf/util/comm.h
+++ b/tools/perf/util/comm.h
@@ -16,6 +16,6 @@ struct comm {
 void comm__free(struct comm *comm);
 struct comm *comm__new(const char *str, u64 timestamp);
 const char *comm__str(const struct comm *comm);
-void comm__override(struct comm *comm, const char *str, u64 timestamp);
+int comm__override(struct comm *comm, const char *str, u64 timestamp);
 
 #endif  /* __PERF_COMM_H */
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index a4ee6b4a840f..a8a9b6cd93a8 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -72,6 +72,7 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
 static int convert_name_to_addr(struct perf_probe_event *pev,
                                 const char *exec);
+static void clear_probe_trace_event(struct probe_trace_event *tev);
 static struct machine machine;
 
 /* Initialize symbol maps and path of vmlinux/modules */
@@ -172,54 +173,6 @@ const char *kernel_get_module_path(const char *module)
         return (dso) ? dso->long_name : NULL;
 }
 
-#ifdef HAVE_DWARF_SUPPORT
-/* Copied from unwind.c */
-static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
-                                    GElf_Shdr *shp, const char *name)
-{
-        Elf_Scn *sec = NULL;
-
-        while ((sec = elf_nextscn(elf, sec)) != NULL) {
-                char *str;
-
-                gelf_getshdr(sec, shp);
-                str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
-                if (!strcmp(name, str))
-                        break;
-        }
-
-        return sec;
-}
-
-static int get_text_start_address(const char *exec, unsigned long *address)
-{
-        Elf *elf;
-        GElf_Ehdr ehdr;
-        GElf_Shdr shdr;
-        int fd, ret = -ENOENT;
-
-        fd = open(exec, O_RDONLY);
-        if (fd < 0)
-                return -errno;
-
-        elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
-        if (elf == NULL)
-                return -EINVAL;
-
-        if (gelf_getehdr(elf, &ehdr) == NULL)
-                goto out;
-
-        if (!elf_section_by_name(elf, &ehdr, &shdr, ".text"))
-                goto out;
-
-        *address = shdr.sh_addr - shdr.sh_offset;
-        ret = 0;
-out:
-        elf_end(elf);
-        return ret;
-}
-#endif
-
 static int init_user_exec(void)
 {
         int ret = 0;
@@ -340,6 +293,34 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
         return 0;
 }
 
+static int get_text_start_address(const char *exec, unsigned long *address)
+{
+        Elf *elf;
+        GElf_Ehdr ehdr;
+        GElf_Shdr shdr;
+        int fd, ret = -ENOENT;
+
+        fd = open(exec, O_RDONLY);
+        if (fd < 0)
+                return -errno;
+
+        elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
+        if (elf == NULL)
+                return -EINVAL;
+
+        if (gelf_getehdr(elf, &ehdr) == NULL)
+                goto out;
+
+        if (!elf_section_by_name(elf, &ehdr, &shdr, ".text", NULL))
+                goto out;
+
+        *address = shdr.sh_addr - shdr.sh_offset;
+        ret = 0;
+out:
+        elf_end(elf);
+        return ret;
+}
+
 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,
                                           int ntevs, const char *exec)
 {
@@ -407,6 +388,14 @@ static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
         return ret;
 }
 
+static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
+{
+        int i;
+
+        for (i = 0; i < ntevs; i++)
+                clear_probe_trace_event(tevs + i);
+}
+
 /* Try to find perf_probe_event with debuginfo */
 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                           struct probe_trace_event **tevs,
@@ -442,6 +431,10 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
                                 ret = add_module_to_probe_trace_events(*tevs,
                                                  ntevs, target);
                 }
+                if (ret < 0) {
+                        clear_probe_trace_events(*tevs, ntevs);
+                        zfree(tevs);
+                }
                 return ret < 0 ? ret : ntevs;
         }
 
@@ -781,6 +774,28 @@ int show_available_vars(struct perf_probe_event *pevs __maybe_unused,
 }
 #endif
 
+void line_range__clear(struct line_range *lr)
+{
+        struct line_node *ln;
+
+        free(lr->function);
+        free(lr->file);
+        free(lr->path);
+        free(lr->comp_dir);
+        while (!list_empty(&lr->line_list)) {
+                ln = list_first_entry(&lr->line_list, struct line_node, list);
+                list_del(&ln->list);
+                free(ln);
+        }
+        memset(lr, 0, sizeof(*lr));
+}
+
+void line_range__init(struct line_range *lr)
+{
+        memset(lr, 0, sizeof(*lr));
+        INIT_LIST_HEAD(&lr->line_list);
+}
+
 static int parse_line_num(char **ptr, int *val, const char *what)
 {
         const char *start = *ptr;
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index d481c46e0796..fcaf7273e85a 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -120,6 +120,12 @@ extern void clear_perf_probe_event(struct perf_probe_event *pev);
 /* Command string to line-range */
 extern int parse_line_range_desc(const char *cmd, struct line_range *lr);
 
+/* Release line range members */
+extern void line_range__clear(struct line_range *lr);
+
+/* Initialize line range */
+extern void line_range__init(struct line_range *lr);
+
 /* Internal use: Return kernel/module path */
 extern const char *kernel_get_module_path(const char *module);
 
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 4b0a127a4d3b..759456728703 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -136,9 +136,8 @@ static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
         return -1;
 }
 
-static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
-                                    GElf_Shdr *shp, const char *name,
-                                    size_t *idx)
+Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
+                             GElf_Shdr *shp, const char *name, size_t *idx)
 {
         Elf_Scn *sec = NULL;
         size_t cnt = 1;
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index cbd680361806..fffe2888a1c7 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -52,6 +52,11 @@ static inline char *bfd_demangle(void __maybe_unused *v,
 # define PERF_ELF_C_READ_MMAP ELF_C_READ
 #endif
 
+#ifdef HAVE_LIBELF_SUPPORT
+extern Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
+                                GElf_Shdr *shp, const char *name, size_t *idx);
+#endif
+
 #ifndef DMGL_PARAMS
 #define DMGL_PARAMS      (1 << 0)       /* Include function args */
 #define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index e3948612543e..0358882c8910 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -66,10 +66,13 @@ struct comm *thread__comm(const struct thread *thread)
 int thread__set_comm(struct thread *thread, const char *str, u64 timestamp)
 {
         struct comm *new, *curr = thread__comm(thread);
+        int err;
 
         /* Override latest entry if it had no specific time coverage */
         if (!curr->start) {
-                comm__override(curr, str, timestamp);
+                err = comm__override(curr, str, timestamp);
+                if (err)
+                        return err;
         } else {
                 new = comm__new(str, timestamp);
                 if (!new)
diff --git a/tools/perf/util/unwind.c b/tools/perf/util/unwind.c
index 416f22bf3693..742f23bf35ff 100644
--- a/tools/perf/util/unwind.c
+++ b/tools/perf/util/unwind.c
@@ -28,6 +28,7 @@
 #include "session.h"
 #include "perf_regs.h"
 #include "unwind.h"
+#include "symbol.h"
 #include "util.h"
 
 extern int
@@ -158,23 +159,6 @@ static int __dw_read_encoded_value(u8 **p, u8 *end, u64 *val,
         __v;                                                    \
         })
 
-static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
-                                    GElf_Shdr *shp, const char *name)
-{
-        Elf_Scn *sec = NULL;
-
-        while ((sec = elf_nextscn(elf, sec)) != NULL) {
-                char *str;
-
-                gelf_getshdr(sec, shp);
-                str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
-                if (!strcmp(name, str))
-                        break;
-        }
-
-        return sec;
-}
-
 static u64 elf_section_offset(int fd, const char *name)
 {
         Elf *elf;
@@ -190,7 +174,7 @@ static u64 elf_section_offset(int fd, const char *name)
                 if (gelf_getehdr(elf, &ehdr) == NULL)
                         break;
 
-                if (!elf_section_by_name(elf, &ehdr, &shdr, name))
+                if (!elf_section_by_name(elf, &ehdr, &shdr, name, NULL))
                         break;
 
                 offset = shdr.sh_offset;