perf tools: Handle injected guest kernel mmap event

If a kernel mmap event was recorded inside a guest and injected into a host
perf.data file, then it will match a host mmap_name not a guest mmap_name,
see machine__set_mmap_name(). So try matching a host mmap_name in that
case.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-27-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 44da170..facc13f 100644 (file)
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1742,6 +1742,7 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
        struct map *map;
        enum dso_space_type dso_space;
        bool is_kernel_mmap;
+       const char *mmap_name = machine->mmap_name;
 
        /* If we have maps from kcore then we do not need or want any others */
        if (machine__uses_kcore(machine))
@@ -1752,8 +1753,16 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
        else
                dso_space = DSO_SPACE__KERNEL_GUEST;
 
-       is_kernel_mmap = memcmp(xm->name, machine->mmap_name,
-                               strlen(machine->mmap_name) - 1) == 0;
+       is_kernel_mmap = memcmp(xm->name, mmap_name, strlen(mmap_name) - 1) == 0;
+       if (!is_kernel_mmap && !machine__is_host(machine)) {
+               /*
+                * If the event was recorded inside the guest and injected into
+                * the host perf.data file, then it will match a host mmap_name,
+                * so try that - see machine__set_mmap_name().
+                */
+               mmap_name = "[kernel.kallsyms]";
+               is_kernel_mmap = memcmp(xm->name, mmap_name, strlen(mmap_name) - 1) == 0;
+       }
        if (xm->name[0] == '/' ||
            (!is_kernel_mmap && xm->name[0] == '[')) {
                map = machine__addnew_module_map(machine, xm->start,
@@ -1767,7 +1776,7 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
                        dso__set_build_id(map->dso, bid);
 
        } else if (is_kernel_mmap) {
-               const char *symbol_name = (xm->name + strlen(machine->mmap_name));
+               const char *symbol_name = xm->name + strlen(mmap_name);
                /*
                 * Should be there already, from the build-id table in
                 * the header.