perf maps: Add functions to access maps

Introduce functions to access struct maps. These functions reduce the
number of places reference counting is necessary. While tidying APIs do
some small const-ification, in particlar to unwind_libunwind_ops.

Committer notes:

Fixed up tools/perf/util/unwind-libunwind.c:

-               return ops->get_entries(cb, arg, thread, data, max_stack);
+               return ops->get_entries(cb, arg, thread, data, max_stack, best_effort);

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/scripts/python/Perf-Trace-Util/Context.c

@@ -100,10 +100,11 @@ static PyObject *perf_sample_insn(PyObject *obj, PyObject *args)
 	if (!c)
 		return NULL;
 
-	if (c->sample->ip && !c->sample->insn_len &&
-	    c->al->thread->maps && c->al->thread->maps->machine)
-		script_fetch_insn(c->sample, c->al->thread, c->al->thread->maps->machine);
+	if (c->sample->ip && !c->sample->insn_len && c->al->thread->maps) {
+		struct machine *machine =  maps__machine(c->al->thread->maps);
 
+		script_fetch_insn(c->sample, c->al->thread, machine);
+	}
 	if (!c->sample->insn_len)
 		Py_RETURN_NONE; /* N.B. This is a return statement */
 

tools/perf/tests/code-reading.c

@@ -269,7 +269,7 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 		len = al.map->end - addr;
 
 	/* Read the object code using perf */
-	ret_len = dso__data_read_offset(al.map->dso, thread->maps->machine,
+	ret_len = dso__data_read_offset(al.map->dso, maps__machine(thread->maps),
 					al.addr, buf1, len);
 	if (ret_len != len) {
 		pr_debug("dso__data_read_offset failed\n");

tools/perf/ui/browsers/hists.c

@@ -3139,7 +3139,8 @@ static int evsel__hists_browse(struct evsel *evsel, int nr_events, const char *h
 			continue;
 		case 'k':
 			if (browser->selection != NULL)
-				hists_browser__zoom_map(browser, browser->selection->maps->machine->vmlinux_map);
+				hists_browser__zoom_map(browser,
+					      maps__machine(browser->selection->maps)->vmlinux_map);
 			continue;
 		case 'V':
 			verbose = (verbose + 1) % 4;

tools/perf/util/callchain.c

@@ -1112,6 +1112,8 @@ int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *samp
 int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node,
 			bool hide_unresolved)
 {
+	struct machine *machine = maps__machine(node->ms.maps);
+
 	al->maps = node->ms.maps;
 	al->map = node->ms.map;
 	al->sym = node->ms.sym;
@@ -1124,17 +1126,16 @@ int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *
 		if (al->map == NULL)
 			goto out;
 	}
-
-	if (al->maps == machine__kernel_maps(al->maps->machine)) {
-		if (machine__is_host(al->maps->machine)) {
+	if (al->maps == machine__kernel_maps(machine)) {
+		if (machine__is_host(machine)) {
 			al->cpumode = PERF_RECORD_MISC_KERNEL;
 			al->level = 'k';
 		} else {
 			al->cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
 			al->level = 'g';
 		}
 	} else {
-		if (machine__is_host(al->maps->machine)) {
+		if (machine__is_host(machine)) {
 			al->cpumode = PERF_RECORD_MISC_USER;
 			al->level = '.';
 		} else if (perf_guest) {

tools/perf/util/db-export.c

@@ -181,7 +181,7 @@ static int db_ids_from_al(struct db_export *dbe, struct addr_location *al,
 	if (al->map) {
 		struct dso *dso = al->map->dso;
 
-		err = db_export__dso(dbe, dso, al->maps->machine);
+		err = db_export__dso(dbe, dso, maps__machine(al->maps));
 		if (err)
 			return err;
 		*dso_db_id = dso->db_id;
@@ -354,19 +354,21 @@ int db_export__sample(struct db_export *dbe, union perf_event *event,
 	};
 	struct thread *main_thread;
 	struct comm *comm = NULL;
+	struct machine *machine;
 	int err;
 
 	err = db_export__evsel(dbe, evsel);
 	if (err)
 		return err;
 
-	err = db_export__machine(dbe, al->maps->machine);
+	machine = maps__machine(al->maps);
+	err = db_export__machine(dbe, machine);
 	if (err)
 		return err;
 
-	main_thread = thread__main_thread(al->maps->machine, thread);
+	main_thread = thread__main_thread(machine, thread);
 
-	err = db_export__threads(dbe, thread, main_thread, al->maps->machine, &comm);
+	err = db_export__threads(dbe, thread, main_thread, machine, &comm);
 	if (err)
 		goto out_put;
 
@@ -380,7 +382,7 @@ int db_export__sample(struct db_export *dbe, union perf_event *event,
 		goto out_put;
 
 	if (dbe->cpr) {
-		struct call_path *cp = call_path_from_sample(dbe, al->maps->machine,
+		struct call_path *cp = call_path_from_sample(dbe, machine,
 							     thread, sample,
 							     evsel);
 		if (cp) {

tools/perf/util/dlfilter.c

@@ -197,8 +197,12 @@ static const __u8 *dlfilter__insn(void *ctx, __u32 *len)
 		if (!al->thread && machine__resolve(d->machine, al, d->sample) < 0)
 			return NULL;
 
-		if (al->thread->maps && al->thread->maps->machine)
-			script_fetch_insn(d->sample, al->thread, al->thread->maps->machine);
+		if (al->thread->maps) {
+			struct machine *machine = maps__machine(al->thread->maps);
+
+			if (machine)
+				script_fetch_insn(d->sample, al->thread, machine);
+		}
 	}
 
 	if (!d->sample->insn_len)

tools/perf/util/event.c

@@ -572,7 +572,7 @@ struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr,
 			     struct addr_location *al)
 {
 	struct maps *maps = thread->maps;
-	struct machine *machine = maps->machine;
+	struct machine *machine = maps__machine(maps);
 	bool load_map = false;
 
 	al->maps = maps;
@@ -637,7 +637,7 @@ struct map *thread__find_map_fb(struct thread *thread, u8 cpumode, u64 addr,
 				struct addr_location *al)
 {
 	struct map *map = thread__find_map(thread, cpumode, addr, al);
-	struct machine *machine = thread->maps->machine;
+	struct machine *machine = maps__machine(thread->maps);
 	u8 addr_cpumode = machine__addr_cpumode(machine, cpumode, addr);
 
 	if (map || addr_cpumode == cpumode)

tools/perf/util/hist.c

@@ -241,7 +241,7 @@ void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
 
 	if (h->cgroup) {
 		const char *cgrp_name = "unknown";
-		struct cgroup *cgrp = cgroup__find(h->ms.maps->machine->env,
+		struct cgroup *cgrp = cgroup__find(maps__machine(h->ms.maps)->env,
 						   h->cgroup);
 		if (cgrp != NULL)
 			cgrp_name = cgrp->name;

tools/perf/util/machine.c

@@ -2847,7 +2847,7 @@ static int find_prev_cpumode(struct ip_callchain *chain, struct thread *thread,
 static u64 get_leaf_frame_caller(struct perf_sample *sample,
 		struct thread *thread, int usr_idx)
 {
-	if (machine__normalized_is(thread->maps->machine, "arm64"))
+	if (machine__normalized_is(maps__machine(thread->maps), "arm64"))
 		return get_leaf_frame_caller_aarch64(sample, thread, usr_idx);
 	else
 		return 0;

tools/perf/util/map.c

@@ -234,7 +234,7 @@ bool __map__is_kernel(const struct map *map)
 {
 	if (!map->dso->kernel)
 		return false;
-	return machine__kernel_map(map__kmaps((struct map *)map)->machine) == map;
+	return machine__kernel_map(maps__machine(map__kmaps((struct map *)map))) == map;
 }
 
 bool __map__is_extra_kernel_map(const struct map *map)
@@ -475,11 +475,15 @@ u64 map__rip_2objdump(struct map *map, u64 rip)
 	 * kcore may not either. However the trampoline object code is on the
 	 * main kernel map, so just use that instead.
 	 */
-	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps && kmap->kmaps->machine) {
-		struct map *kernel_map = machine__kernel_map(kmap->kmaps->machine);
+	if (kmap && is_entry_trampoline(kmap->name) && kmap->kmaps) {
+		struct machine *machine = maps__machine(kmap->kmaps);
 
-		if (kernel_map)
-			map = kernel_map;
+		if (machine) {
+			struct map *kernel_map = machine__kernel_map(machine);
+
+			if (kernel_map)
+				map = kernel_map;
+		}
 	}
 
 	if (!map->dso->adjust_symbols)