perf/core improvements and fixes

index 026ec0c749b0..0e3c1cecef1b 100644
@@ -3109,7 +3109,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
 			"per thread proc mmap processing timeout in ms"),
 	OPT_END()
 	};
-	bool max_stack_user_set = true;
+	bool __maybe_unused max_stack_user_set = true;
 	bool mmap_pages_user_set = true;
 	const char * const trace_subcommands[] = { "record", NULL };
 	int err;

index b993218744d4..8a644fef452c 100644
@@ -420,7 +420,7 @@ for ((_evsel) = list_entry((_leader)->node.next, struct perf_evsel, node); 	\
      (_evsel) && (_evsel)->leader == (_leader);					\
      (_evsel) = list_entry((_evsel)->node.next, struct perf_evsel, node))
 
-static inline bool has_branch_callstack(struct perf_evsel *evsel)
+static inline bool perf_evsel__has_branch_callstack(const struct perf_evsel *evsel)
 {
 	return evsel->attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK;
 }

index 0c4dabc69932..52b51e004fe8 100644
@@ -1808,7 +1808,7 @@ static int thread__resolve_callchain_sample(struct thread *thread,
 
 	callchain_cursor_reset(cursor);
 
-	if (has_branch_callstack(evsel)) {
+	if (perf_evsel__has_branch_callstack(evsel)) {
 		err = resolve_lbr_callchain_sample(thread, cursor, sample, parent,
 						   root_al, max_stack);
 		if (err)

index ca1827c4af4a..2335b2824d8a 100644
@@ -907,7 +907,7 @@ static void callchain__printf(struct perf_evsel *evsel,
 	unsigned int i;
 	struct ip_callchain *callchain = sample->callchain;
 
-	if (has_branch_callstack(evsel))
+	if (perf_evsel__has_branch_callstack(evsel))
 		callchain__lbr_callstack_printf(sample);
 
 	printf("... FP chain: nr:%" PRIu64 "\n", callchain->nr);

@@ -1081,7 +1081,7 @@ static void dump_sample(struct perf_evsel *evsel, union perf_event *event,
 	if (sample_type & PERF_SAMPLE_CALLCHAIN)
 		callchain__printf(evsel, sample);
 
-	if ((sample_type & PERF_SAMPLE_BRANCH_STACK) && !has_branch_callstack(evsel))
+	if ((sample_type & PERF_SAMPLE_BRANCH_STACK) && !perf_evsel__has_branch_callstack(evsel))
 		branch_stack__printf(sample);
 
 	if (sample_type & PERF_SAMPLE_REGS_USER)

index 0e93282b405e..5099740aa50b 100644
@@ -791,7 +791,7 @@ static void process_event(struct perf_script *script,
 	if (PRINT_FIELD(IP)) {
 		struct callchain_cursor *cursor = NULL, cursor_callchain;
 
-		if (symbol_conf.use_callchain &&
+		if (symbol_conf.use_callchain && sample->callchain &&
 		    thread__resolve_callchain(al->thread, &cursor_callchain, evsel,
 					      sample, NULL, NULL, scripting_max_stack) == 0)
 			cursor = &cursor_callchain;

index 2b4ceaf058bb..aa248dcb4440 100644
@@ -109,6 +109,7 @@ __parse_callchain_report_opt(const char *arg, bool allow_record_opt)
 	bool record_opt_set = false;
 	bool try_stack_size = false;
 
+	callchain_param.enabled = true;
 	symbol_conf.use_callchain = true;
 
 	if (!arg)

@@ -117,6 +118,7 @@ __parse_callchain_report_opt(const char *arg, bool allow_record_opt)
 	while ((tok = strtok((char *)arg, ",")) != NULL) {
 		if (!strncmp(tok, "none", strlen(tok))) {
 			callchain_param.mode = CHAIN_NONE;
+			callchain_param.enabled = false;
 			symbol_conf.use_callchain = false;
 			return 0;
 		}

index 160ea23b45aa..1d5be0bd426f 100644
@@ -47,7 +47,6 @@ struct report {
 	struct perf_tool	tool;
 	struct perf_session	*session;
 	bool			use_tui, use_gtk, use_stdio;
-	bool			dont_use_callchains;
 	bool			show_full_info;
 	bool			show_threads;
 	bool			inverted_callchain;

@@ -247,7 +246,7 @@ static int report__setup_sample_type(struct report *rep)
 				  "you call 'perf record' without -g?\n");
 			return -1;
 		}
-	} else if (!rep->dont_use_callchains &&
+	} else if (!callchain_param.enabled &&
 		   callchain_param.mode != CHAIN_NONE &&
 		   !symbol_conf.use_callchain) {
 			symbol_conf.use_callchain = true;

@@ -599,13 +598,15 @@ static int __cmd_report(struct report *rep)
 static int
 report_parse_callchain_opt(const struct option *opt, const char *arg, int unset)
 {
-	struct report *rep = (struct report *)opt->value;
+	struct callchain_param *callchain = opt->value;
 
+	callchain->enabled = !unset;
 	/*
 	 * --no-call-graph
 	 */
 	if (unset) {
-		rep->dont_use_callchains = true;
+		symbol_conf.use_callchain = false;
+		callchain->mode = CHAIN_NONE;
 		return 0;
 	}
 

@@ -734,7 +735,7 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
 		   "regex filter to identify parent, see: '--sort parent'"),
 	OPT_BOOLEAN('x', "exclude-other", &symbol_conf.exclude_other,
 		    "Only display entries with parent-match"),
-	OPT_CALLBACK_DEFAULT('g', "call-graph", &report,
+	OPT_CALLBACK_DEFAULT('g', "call-graph", &callchain_param,
 			     "print_type,threshold[,print_limit],order,sort_key[,branch],value",
 			     report_callchain_help, &report_parse_callchain_opt,
 			     callchain_default_opt),

index 5b4758a08a49..bd9593346bb2 100644
@@ -946,7 +946,6 @@ int record_opts__parse_callchain(struct record_opts *record,
 				 const char *arg, bool unset)
 {
 	int ret;
-	record->callgraph_set = true;
 	callchain->enabled = !unset;
 
 	/* --no-call-graph */

@@ -978,15 +977,14 @@ int record_callchain_opt(const struct option *opt,
 			 const char *arg __maybe_unused,
 			 int unset __maybe_unused)
 {
-	struct record_opts *record = (struct record_opts *)opt->value;
+	struct callchain_param *callchain = opt->value;
 
-	record->callgraph_set = true;
-	callchain_param.enabled = true;
+	callchain->enabled = true;
 
-	if (callchain_param.record_mode == CALLCHAIN_NONE)
-		callchain_param.record_mode = CALLCHAIN_FP;
+	if (callchain->record_mode == CALLCHAIN_NONE)
+		callchain->record_mode = CALLCHAIN_FP;
 
-	callchain_debug(&callchain_param);
+	callchain_debug(callchain);
 	return 0;
 }
 

@@ -1224,7 +1222,7 @@ struct option __record_options[] = {
 		     record__parse_mmap_pages),
 	OPT_BOOLEAN(0, "group", &record.opts.group,
 		    "put the counters into a counter group"),
-	OPT_CALLBACK_NOOPT('g', NULL, &record.opts,
+	OPT_CALLBACK_NOOPT('g', NULL, &callchain_param,
 			   NULL, "enables call-graph recording" ,
 			   &record_callchain_opt),
 	OPT_CALLBACK(0, "call-graph", &record.opts,

index 8846df0ec0c3..f0cfdf394fac 100644
@@ -1045,18 +1045,17 @@ callchain_opt(const struct option *opt, const char *arg, int unset)
 static int
 parse_callchain_opt(const struct option *opt, const char *arg, int unset)
 {
-	struct record_opts *record = (struct record_opts *)opt->value;
+	struct callchain_param *callchain = opt->value;
 
-	record->callgraph_set = true;
-	callchain_param.enabled = !unset;
-	callchain_param.record_mode = CALLCHAIN_FP;
+	callchain->enabled = !unset;
+	callchain->record_mode = CALLCHAIN_FP;
 
 	/*
 	 * --no-call-graph
 	 */
 	if (unset) {
 		symbol_conf.use_callchain = false;
-		callchain_param.record_mode = CALLCHAIN_NONE;
+		callchain->record_mode = CALLCHAIN_NONE;
 		return 0;
 	}
 

@@ -1162,10 +1161,10 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 		   "output field(s): overhead, period, sample plus all of sort keys"),
 	OPT_BOOLEAN('n', "show-nr-samples", &symbol_conf.show_nr_samples,
 		    "Show a column with the number of samples"),
-	OPT_CALLBACK_NOOPT('g', NULL, &top.record_opts,
+	OPT_CALLBACK_NOOPT('g', NULL, &callchain_param,
 			   NULL, "enables call-graph recording and display",
 			   &callchain_opt),
-	OPT_CALLBACK(0, "call-graph", &top.record_opts,
+	OPT_CALLBACK(0, "call-graph", &callchain_param,
 		     "record_mode[,record_size],print_type,threshold[,print_limit],order,sort_key[,branch]",
 		     top_callchain_help, &parse_callchain_opt),
 	OPT_BOOLEAN(0, "children", &symbol_conf.cumulate_callchain,

index 0e3c1cecef1b..5e2614bbb48d 100644
@@ -2457,7 +2457,7 @@ static int trace__add_syscall_newtp(struct trace *trace)
 	perf_evlist__add(evlist, sys_enter);
 	perf_evlist__add(evlist, sys_exit);
 
-	if (trace->opts.callgraph_set && !trace->kernel_syscallchains) {
+	if (callchain_param.enabled && !trace->kernel_syscallchains) {
 		/*
 		 * We're interested only in the user space callchain
 		 * leading to the syscall, allow overriding that for

@@ -2546,7 +2546,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
 
 	perf_evlist__config(evlist, &trace->opts, NULL);
 
-	if (trace->opts.callgraph_set && trace->syscalls.events.sys_exit) {
+	if (callchain_param.enabled && trace->syscalls.events.sys_exit) {
 		perf_evsel__config_callchain(trace->syscalls.events.sys_exit,
 					     &trace->opts, &callchain_param);
                /*

@@ -3153,11 +3153,11 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
 	}
 
 #ifdef HAVE_DWARF_UNWIND_SUPPORT
-	if ((trace.min_stack || max_stack_user_set) && !trace.opts.callgraph_set)
+	if ((trace.min_stack || max_stack_user_set) && !callchain_param.enabled)
 		record_opts__parse_callchain(&trace.opts, &callchain_param, "dwarf", false);
 #endif
 
-	if (trace.opts.callgraph_set) {
+	if (callchain_param.enabled) {
 		if (!mmap_pages_user_set && geteuid() == 0)
 			trace.opts.mmap_pages = perf_event_mlock_kb_in_pages() * 4;
 

index 5381a01c0610..cd8f1b150f9e 100644
@@ -52,7 +52,6 @@ struct record_opts {
 	bool	     sample_weight;
 	bool	     sample_time;
 	bool	     sample_time_set;
-	bool	     callgraph_set;
 	bool	     period;
 	bool	     running_time;
 	bool	     full_auxtrace;

index e70df2e54d66..6a4681932ba5 100644
@@ -1896,11 +1896,10 @@ static int hist_browser__fprintf_entry(struct hist_browser *browser,
 	bool first = true;
 	int ret;
 
-	if (symbol_conf.use_callchain)
+	if (symbol_conf.use_callchain) {
 		folded_sign = hist_entry__folded(he);
-
-	if (symbol_conf.use_callchain)
 		printed += fprintf(fp, "%c ", folded_sign);
+	}
 
 	hists__for_each_format(browser->hists, fmt) {
 		if (perf_hpp__should_skip(fmt, he->hists))

index f0cfdf394fac..c130a11d3a0d 100644
@@ -917,15 +917,15 @@ out_err:
 	return -1;
 }
 
-static int perf_top__setup_sample_type(struct perf_top *top __maybe_unused)
+static int callchain_param__setup_sample_type(struct callchain_param *callchain)
 {
 	if (!sort__has_sym) {
-		if (symbol_conf.use_callchain) {
+		if (callchain->enabled) {
 			ui__error("Selected -g but \"sym\" not present in --sort/-s.");
 			return -EINVAL;
 		}
-	} else if (callchain_param.mode != CHAIN_NONE) {
-		if (callchain_register_param(&callchain_param) < 0) {
+	} else if (callchain->mode != CHAIN_NONE) {
+		if (callchain_register_param(callchain) < 0) {
 			ui__error("Can't register callchain params.\n");
 			return -EINVAL;
 		}

@@ -952,7 +952,7 @@ static int __cmd_top(struct perf_top *top)
 			goto out_delete;
 	}
 
-	ret = perf_top__setup_sample_type(top);
+	ret = callchain_param__setup_sample_type(&callchain_param);
 	if (ret)
 		goto out_delete;
 

@@ -1311,7 +1311,7 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 
 	top.sym_evsel = perf_evlist__first(top.evlist);
 
-	if (!symbol_conf.use_callchain) {
+	if (!callchain_param.enabled) {
 		symbol_conf.cumulate_callchain = false;
 		perf_hpp__cancel_cumulate();
 	}

index 52fcef3074fe..86afe9618bb0 100644
@@ -412,7 +412,7 @@ static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
 		return -1;
 	}
 	if (stat(filename, &st))
-		memset(&st, 0, sizeof(stat));
+		memset(&st, 0, sizeof(st));
 
 	event->mmap2.header.type = PERF_RECORD_MMAP2;
 	event->mmap2.header.misc = PERF_RECORD_MISC_USER;

@@ -500,7 +500,7 @@ static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
 	size++; /* for \0 */
 
 	if (stat(filename, &st))
-		memset(&st, 0, sizeof(stat));
+		memset(&st, 0, sizeof(st));
 
 	size = PERF_ALIGN(size, sizeof(u64));
 

index 52b51e004fe8..656c1d7ee7d4 100644
@@ -908,11 +908,11 @@ int machines__create_kernel_maps(struct machines *machines, pid_t pid)
 	return machine__create_kernel_maps(machine);
 }
 
-int machine__load_kallsyms(struct machine *machine, const char *filename,
-			   enum map_type type, symbol_filter_t filter)
+int __machine__load_kallsyms(struct machine *machine, const char *filename,
+			     enum map_type type, bool no_kcore, symbol_filter_t filter)
 {
 	struct map *map = machine__kernel_map(machine);
-	int ret = dso__load_kallsyms(map->dso, filename, map, filter);
+	int ret = __dso__load_kallsyms(map->dso, filename, map, no_kcore, filter);
 
 	if (ret > 0) {
 		dso__set_loaded(map->dso, type);

@@ -927,6 +927,12 @@ int machine__load_kallsyms(struct machine *machine, const char *filename,
 	return ret;
 }
 
+int machine__load_kallsyms(struct machine *machine, const char *filename,
+			   enum map_type type, symbol_filter_t filter)
+{
+	return __machine__load_kallsyms(machine, filename, type, false, filter);
+}
+
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,
 			       symbol_filter_t filter)
 {

index 382873bdc563..4822de5e4544 100644
@@ -215,6 +215,8 @@ struct symbol *machine__find_kernel_function_by_name(struct machine *machine,
 struct map *machine__findnew_module_map(struct machine *machine, u64 start,
 					const char *filename);
 
+int __machine__load_kallsyms(struct machine *machine, const char *filename,
+			     enum map_type type, bool no_kcore, symbol_filter_t filter);
 int machine__load_kallsyms(struct machine *machine, const char *filename,
 			   enum map_type type, symbol_filter_t filter);
 int machine__load_vmlinux_path(struct machine *machine, enum map_type type,

index a36823c3b7c0..415c4f6d98fd 100644
@@ -1208,8 +1208,8 @@ static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
 	return 0;
 }
 
-int dso__load_kallsyms(struct dso *dso, const char *filename,
-		       struct map *map, symbol_filter_t filter)
+int __dso__load_kallsyms(struct dso *dso, const char *filename,
+			 struct map *map, bool no_kcore, symbol_filter_t filter)
 {
 	u64 delta = 0;
 

@@ -1230,12 +1230,18 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
 	else
 		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
 
-	if (!dso__load_kcore(dso, map, filename))
+	if (!no_kcore && !dso__load_kcore(dso, map, filename))
 		return dso__split_kallsyms_for_kcore(dso, map, filter);
 	else
 		return dso__split_kallsyms(dso, map, delta, filter);
 }
 
+int dso__load_kallsyms(struct dso *dso, const char *filename,
+		       struct map *map, symbol_filter_t filter)
+{
+	return __dso__load_kallsyms(dso, filename, map, false, filter);
+}
+
 static int dso__load_perf_map(struct dso *dso, struct map *map,
 			      symbol_filter_t filter)
 {

index 1da7b101bc7f..c8e43979ed5c 100644
@@ -240,6 +240,8 @@ int dso__load_vmlinux(struct dso *dso, struct map *map,
 		      symbol_filter_t filter);
 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
 			   symbol_filter_t filter);
+int __dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map,
+			 bool no_kcore, symbol_filter_t filter);
 int dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map,
 		       symbol_filter_t filter);
 

index 630b0b409b97..c05f1bdd9210 100644
@@ -54,8 +54,14 @@ int test__vmlinux_matches_kallsyms(int subtest __maybe_unused)
 	 * Step 3:
 	 *
 	 * Load and split /proc/kallsyms into multiple maps, one per module.
+	 * Do not use kcore, as this test was designed before kcore support
+	 * and has parts that only make sense if using the non-kcore code.
+	 * XXX: extend it to stress the kcorre code as well, hint: the list
+	 * of modules extracted from /proc/kcore, in its current form, can't
+	 * be compacted against the list of modules found in the "vmlinux"
+	 * code and with the one got from /proc/modules from the "kallsyms" code.
 	 */
-	if (machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, NULL) <= 0) {
+	if (__machine__load_kallsyms(&kallsyms, "/proc/kallsyms", type, true, NULL) <= 0) {
 		pr_debug("dso__load_kallsyms ");
 		goto out;
 	}

index c05f1bdd9210..e63abab7d5a1 100644
@@ -163,6 +163,9 @@ next_pair:
 
 					pr_debug("%#" PRIx64 ": diff name v: %s k: %s\n",
 						 mem_start, sym->name, pair->name);
+				} else {
+					pr_debug("%#" PRIx64 ": diff name v: %s k: %s\n",
+						 mem_start, sym->name, first_pair->name);
 				}
 			}
 		} else