perf addr_location: Add init/exit/copy functions

struct addr_location holds references to multiple reference counted
objects. Add init/exit functions to make maintenance of those more
consistent with the rest of the code and to try to avoid
leaks. Modification of thread reference counts isn't included in this
change.

Committer notes:

I needed to initialize result to sample->ip to make sure is set to
something, fixing a compile time error, mostly keeping the previous
logic as build_alloc_func_list() already does debugging/error prints
about what went wrong if it takes the 'goto out'.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ali Saidi <alisaidi@amazon.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Brian Robbins <brianrob@linux.microsoft.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song <maskray@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Babrou <ivan@cloudflare.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Ye Xingchen <ye.xingchen@zte.com.cn>
Cc: Yuan Can <yuancan@huawei.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230608232823.4027869-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 45 insertions, 21 deletions

diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index 45c7e7722916..783ce61c6d25 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -754,13 +754,15 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 	struct addr_location al;
 	unsigned char buf[INTEL_PT_INSN_BUF_SZ];
 	ssize_t len;
-	int x86_64;
+	int x86_64, ret = 0;
 	u8 cpumode;
 	u64 offset, start_offset, start_ip;
 	u64 insn_cnt = 0;
 	bool one_map = true;
 	bool nr;
 
+
+	addr_location__init(&al);
 	intel_pt_insn->length = 0;
 
 	if (to_ip && *ip == to_ip)
@@ -773,19 +775,22 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 		if (ptq->pt->have_guest_sideband) {
 			if (!ptq->guest_machine || ptq->guest_machine_pid != ptq->pid) {
 				intel_pt_log("ERROR: guest sideband but no guest machine\n");
-				return -EINVAL;
+				ret = -EINVAL;
+				goto out_ret;
 			}
 		} else if ((!symbol_conf.guest_code && cpumode != PERF_RECORD_MISC_GUEST_KERNEL) ||
 			   intel_pt_get_guest(ptq)) {
 			intel_pt_log("ERROR: no guest machine\n");
-			return -EINVAL;
+			ret = -EINVAL;
+			goto out_ret;
 		}
 		machine = ptq->guest_machine;
 		thread = ptq->guest_thread;
 		if (!thread) {
 			if (cpumode != PERF_RECORD_MISC_GUEST_KERNEL) {
 				intel_pt_log("ERROR: no guest thread\n");
-				return -EINVAL;
+				ret = -EINVAL;
+				goto out_ret;
 			}
 			thread = ptq->unknown_guest_thread;
 		}
@@ -794,7 +799,8 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 		if (!thread) {
 			if (cpumode != PERF_RECORD_MISC_KERNEL) {
 				intel_pt_log("ERROR: no thread\n");
-				return -EINVAL;
+				ret = -EINVAL;
+				goto out_ret;
 			}
 			thread = ptq->pt->unknown_thread;
 		}
@@ -808,13 +814,17 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 				intel_pt_log("ERROR: thread has no dso for %#" PRIx64 "\n", *ip);
 			else
 				intel_pt_log("ERROR: thread has no map for %#" PRIx64 "\n", *ip);
-			return -EINVAL;
+			addr_location__exit(&al);
+			ret = -EINVAL;
+			goto out_ret;
 		}
 		dso = map__dso(al.map);
 
 		if (dso->data.status == DSO_DATA_STATUS_ERROR &&
-		    dso__data_status_seen(dso, DSO_DATA_STATUS_SEEN_ITRACE))
-			return -ENOENT;
+			dso__data_status_seen(dso, DSO_DATA_STATUS_SEEN_ITRACE)) {
+			ret = -ENOENT;
+			goto out_ret;
+		}
 
 		offset = map__map_ip(al.map, *ip);
 
@@ -833,7 +843,8 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 				intel_pt_insn->rel = e->rel;
 				memcpy(intel_pt_insn->buf, e->insn, INTEL_PT_INSN_BUF_SZ);
 				intel_pt_log_insn_no_data(intel_pt_insn, *ip);
-				return 0;
+				ret = 0;
+				goto out_ret;
 			}
 		}
 
@@ -854,11 +865,14 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
 					     offset);
 				if (intel_pt_enable_logging)
 					dso__fprintf(dso, intel_pt_log_fp());
-				return -EINVAL;
+				ret = -EINVAL;
+				goto out_ret;
 			}
 
-			if (intel_pt_get_insn(buf, len, x86_64, intel_pt_insn))
-				return -EINVAL;
+			if (intel_pt_get_insn(buf, len, x86_64, intel_pt_insn)) {
+				ret = -EINVAL;
+				goto out_ret;
+			}
 
 			intel_pt_log_insn(intel_pt_insn, *ip);
 
@@ -909,17 +923,20 @@ out:
 
 		e = intel_pt_cache_lookup(map__dso(al.map), machine, start_offset);
 		if (e)
-			return 0;
+			goto out_ret;
 	}
 
 	/* Ignore cache errors */
 	intel_pt_cache_add(map__dso(al.map), machine, start_offset, insn_cnt,
 			   *ip - start_ip, intel_pt_insn);
 
-	return 0;
+out_ret:
+	addr_location__exit(&al);
+	return ret;
 
 out_no_cache:
 	*insn_cnt_ptr = insn_cnt;
+	addr_location__exit(&al);
 	return 0;
 }
 
@@ -968,6 +985,7 @@ static int __intel_pt_pgd_ip(uint64_t ip, void *data)
 	struct addr_location al;
 	u8 cpumode;
 	u64 offset;
+	int res;
 
 	if (ptq->state->to_nr) {
 		if (intel_pt_guest_kernel_ip(ip))
@@ -984,12 +1002,15 @@ static int __intel_pt_pgd_ip(uint64_t ip, void *data)
 	if (!thread)
 		return -EINVAL;
 
+	addr_location__init(&al);
 	if (!thread__find_map(thread, cpumode, ip, &al) || !map__dso(al.map))
 		return -EINVAL;
 
 	offset = map__map_ip(al.map, ip);
 
-	return intel_pt_match_pgd_ip(ptq->pt, ip, offset, map__dso(al.map)->long_name);
+	res = intel_pt_match_pgd_ip(ptq->pt, ip, offset, map__dso(al.map)->long_name);
+	addr_location__exit(&al);
+	return res;
 }
 
 static bool intel_pt_pgd_ip(uint64_t ip, void *data)
@@ -3372,20 +3393,22 @@ static int intel_pt_text_poke(struct intel_pt *pt, union perf_event *event)
 	/* Assume text poke begins in a basic block no more than 4096 bytes */
 	int cnt = 4096 + event->text_poke.new_len;
 	struct thread *thread = pt->unknown_thread;
-	struct addr_location al = { .map = NULL };
+	struct addr_location al;
 	struct machine *machine = pt->machine;
 	struct intel_pt_cache_entry *e;
 	u64 offset;
+	int ret = 0;
 
+	addr_location__init(&al);
 	if (!event->text_poke.new_len)
-		return 0;
+		goto out;
 
 	for (; cnt; cnt--, addr--) {
 		struct dso *dso;
 
 		if (intel_pt_find_map(thread, cpumode, addr, &al)) {
 			if (addr < event->text_poke.addr)
-				return 0;
+				goto out;
 			continue;
 		}
 
@@ -3406,15 +3429,16 @@ static int intel_pt_text_poke(struct intel_pt *pt, union perf_event *event)
 			 * branch instruction before the text poke address.
 			 */
 			if (e->branch != INTEL_PT_BR_NO_BRANCH)
-				return 0;
+				goto out;
 		} else {
 			intel_pt_cache_invalidate(dso, machine, offset);
 			intel_pt_log("Invalidated instruction cache for %s at %#"PRIx64"\n",
 				     dso->long_name, addr);
 		}
 	}
-
-	return 0;
+out:
+	addr_location__exit(&al);
+	return ret;
 }
 
 static int intel_pt_process_event(struct perf_session *session,