[RFC/PATCH 23/38] perf tools: Use map_groups__find_addr_by_time()

From: Namhyung Kim
Date: Fri Oct 02 2015 - 01:26:33 EST


Use timestamp to find a corresponding map so that it can find a match
symbol eventually.

Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/event.c | 81 ++++++++++++++++++++++++++++++++++++++++++------
tools/perf/util/thread.c | 8 +++--
2 files changed, 77 insertions(+), 12 deletions(-)

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index c960cbcd30d4..d7997105ee7a 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -895,12 +895,11 @@ int perf_event__process(struct perf_tool *tool __maybe_unused,
return machine__process_event(machine, event, sample);
}

-static void map_groups__find_addr_map(struct map_groups *mg, u8 cpumode,
- enum map_type type, u64 addr,
- struct addr_location *al)
+static bool map_groups__set_addr_location(struct map_groups *mg,
+ struct addr_location *al,
+ u8 cpumode, u64 addr)
{
struct machine *machine = mg->machine;
- bool load_map = false;

al->machine = machine;
al->addr = addr;
@@ -909,21 +908,17 @@ static void map_groups__find_addr_map(struct map_groups *mg, u8 cpumode,

if (machine == NULL) {
al->map = NULL;
- return;
+ return true;
}

BUG_ON(mg == NULL);

if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
al->level = 'k';
- mg = &machine->kmaps;
- load_map = true;
} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
al->level = '.';
} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
al->level = 'g';
- mg = &machine->kmaps;
- load_map = true;
} else if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest) {
al->level = 'u';
} else {
@@ -939,8 +934,27 @@ static void map_groups__find_addr_map(struct map_groups *mg, u8 cpumode,
!perf_host)
al->filtered |= (1 << HIST_FILTER__HOST);

+ return true;
+ }
+ return false;
+}
+
+static void map_groups__find_addr_map(struct map_groups *mg, u8 cpumode,
+ enum map_type type, u64 addr,
+ struct addr_location *al)
+{
+ struct machine *machine = mg->machine;
+ bool load_map = false;
+
+ if (map_groups__set_addr_location(mg, al, cpumode, addr))
return;
+
+ if ((cpumode == PERF_RECORD_MISC_KERNEL && perf_host) ||
+ (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest)) {
+ mg = &machine->kmaps;
+ load_map = true;
}
+
try_again:
al->map = map_groups__find(mg, type, al->addr);
if (al->map == NULL) {
@@ -971,6 +985,53 @@ try_again:
}
}

+static void map_groups__find_addr_map_by_time(struct map_groups *mg, u8 cpumode,
+ enum map_type type, u64 addr,
+ struct addr_location *al,
+ u64 timestamp)
+{
+ struct machine *machine = mg->machine;
+ bool load_map = false;
+
+ if (map_groups__set_addr_location(mg, al, cpumode, addr))
+ return;
+
+ if ((cpumode == PERF_RECORD_MISC_KERNEL && perf_host) ||
+ (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest)) {
+ mg = &machine->kmaps;
+ load_map = true;
+ }
+
+try_again:
+ al->map = map_groups__find_by_time(mg, type, al->addr, timestamp);
+ if (al->map == NULL) {
+ /*
+ * If this is outside of all known maps, and is a negative
+ * address, try to look it up in the kernel dso, as it might be
+ * a vsyscall or vdso (which executes in user-mode).
+ *
+ * XXX This is nasty, we should have a symbol list in the
+ * "[vdso]" dso, but for now lets use the old trick of looking
+ * in the whole kernel symbol list.
+ */
+ if (cpumode == PERF_RECORD_MISC_USER && machine &&
+ mg != &machine->kmaps &&
+ machine__kernel_ip(machine, al->addr)) {
+ mg = &machine->kmaps;
+ load_map = true;
+ goto try_again;
+ }
+ } else {
+ /*
+ * Kernel maps might be changed when loading symbols so loading
+ * must be done prior to using kernel maps.
+ */
+ if (load_map)
+ map__load(al->map, machine->symbol_filter);
+ al->addr = al->map->map_ip(al->map, al->addr);
+ }
+}
+
void thread__find_addr_map(struct thread *thread, u8 cpumode,
enum map_type type, u64 addr,
struct addr_location *al)
@@ -991,7 +1052,7 @@ void thread__find_addr_map_by_time(struct thread *thread, u8 cpumode,
mg = thread->mg;

al->thread = thread;
- map_groups__find_addr_map(mg, cpumode, type, addr, al);
+ map_groups__find_addr_map_by_time(mg, cpumode, type, addr, al, timestamp);
}

void thread__find_addr_location(struct thread *thread,
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index efd510d5d966..21de681415f4 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -337,8 +337,12 @@ size_t thread__fprintf(struct thread *thread, FILE *fp)

void thread__insert_map(struct thread *thread, struct map *map)
{
- map_groups__fixup_overlappings(thread->mg, map, stderr);
- map_groups__insert(thread->mg, map);
+ if (perf_has_index) {
+ map_groups__insert_by_time(thread->mg, map);
+ } else {
+ map_groups__fixup_overlappings(thread->mg, map, stderr);
+ map_groups__insert(thread->mg, map);
+ }
}

static int thread__clone_map_groups(struct thread *thread,
--
2.6.0

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