Like the kernel text, the location of x86 PTI entry trampolines must be
recorded in the perf.data file. Like the kernel, synthesize a mmap event
for that, and add processing for it.

Signed-off-by: Adrian Hunter <adrian.hun...@intel.com>
---
 tools/perf/arch/x86/util/Build   |  1 +
 tools/perf/arch/x86/util/event.c | 76 ++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/event.c          | 34 ++++++++++++++----
 tools/perf/util/event.h          |  8 +++++
 tools/perf/util/machine.c        | 28 +++++++++++++++
 5 files changed, 140 insertions(+), 7 deletions(-)
 create mode 100644 tools/perf/arch/x86/util/event.c

diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build
index aa1ce5f6cc00..844b8f335532 100644
--- a/tools/perf/arch/x86/util/Build
+++ b/tools/perf/arch/x86/util/Build
@@ -5,6 +5,7 @@ libperf-y += kvm-stat.o
 libperf-y += perf_regs.o
 libperf-y += group.o
 libperf-y += machine.o
+libperf-y += event.o
 
 libperf-$(CONFIG_DWARF) += dwarf-regs.o
 libperf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o
diff --git a/tools/perf/arch/x86/util/event.c b/tools/perf/arch/x86/util/event.c
new file mode 100644
index 000000000000..675a0213044d
--- /dev/null
+++ b/tools/perf/arch/x86/util/event.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/types.h>
+#include <linux/string.h>
+
+#include "../../util/machine.h"
+#include "../../util/tool.h"
+#include "../../util/map.h"
+#include "../../util/util.h"
+#include "../../util/debug.h"
+
+#if defined(__x86_64__)
+
+int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
+                                      perf_event__handler_t process,
+                                      struct machine *machine)
+{
+       int rc = 0;
+       struct map *pos;
+       struct map_groups *kmaps = &machine->kmaps;
+       struct maps *maps = &kmaps->maps;
+       union perf_event *event = zalloc(sizeof(event->mmap) +
+                                        machine->id_hdr_size);
+
+       if (!event) {
+               pr_debug("Not enough memory synthesizing mmap event "
+                        "for extra kernel maps\n");
+               return -1;
+       }
+
+       for (pos = maps__first(maps); pos; pos = map__next(pos)) {
+               struct kmap *kmap;
+               size_t size;
+
+               if (!__map__is_extra_kernel_map(pos))
+                       continue;
+
+               kmap = map__kmap(pos);
+
+               size = sizeof(event->mmap) - sizeof(event->mmap.filename) +
+                      PERF_ALIGN(strlen(kmap->name) + 1, sizeof(u64)) +
+                      machine->id_hdr_size;
+
+               memset(event, 0, size);
+
+               event->mmap.header.type = PERF_RECORD_MMAP;
+
+               /*
+                * kernel uses 0 for user space maps, see kernel/perf_event.c
+                * __perf_event_mmap
+                */
+               if (machine__is_host(machine))
+                       event->header.misc = PERF_RECORD_MISC_KERNEL;
+               else
+                       event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
+
+               event->mmap.header.size = size;
+
+               event->mmap.start = pos->start;
+               event->mmap.len   = pos->end - pos->start;
+               event->mmap.pgoff = pos->pgoff;
+               event->mmap.pid   = machine->pid;
+
+               strlcpy(event->mmap.filename, kmap->name, PATH_MAX);
+
+               if (perf_tool__process_synth_event(tool, event, machine,
+                                                  process) != 0) {
+                       rc = -1;
+                       break;
+               }
+       }
+
+       free(event);
+       return rc;
+}
+
+#endif
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index aafa9878465f..0c8ecf0c78a4 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -88,10 +88,10 @@ static const char *perf_ns__name(unsigned int id)
        return perf_ns__names[id];
 }
 
-static int perf_tool__process_synth_event(struct perf_tool *tool,
-                                         union perf_event *event,
-                                         struct machine *machine,
-                                         perf_event__handler_t process)
+int perf_tool__process_synth_event(struct perf_tool *tool,
+                                  union perf_event *event,
+                                  struct machine *machine,
+                                  perf_event__handler_t process)
 {
        struct perf_sample synth_sample = {
        .pid       = -1,
@@ -888,9 +888,16 @@ int kallsyms__get_function_start(const char 
*kallsyms_filename,
        return 0;
 }
 
-int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
-                                      perf_event__handler_t process,
-                                      struct machine *machine)
+int __weak perf_event__synthesize_extra_kmaps(struct perf_tool *tool 
__maybe_unused,
+                                             perf_event__handler_t process 
__maybe_unused,
+                                             struct machine *machine 
__maybe_unused)
+{
+       return 0;
+}
+
+static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
+                                               perf_event__handler_t process,
+                                               struct machine *machine)
 {
        size_t size;
        struct map *map = machine__kernel_map(machine);
@@ -943,6 +950,19 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool 
*tool,
        return err;
 }
 
+int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
+                                      perf_event__handler_t process,
+                                      struct machine *machine)
+{
+       int err;
+
+       err = __perf_event__synthesize_kernel_mmap(tool, process, machine);
+       if (err < 0)
+               return err;
+
+       return perf_event__synthesize_extra_kmaps(tool, process, machine);
+}
+
 int perf_event__synthesize_thread_map2(struct perf_tool *tool,
                                      struct thread_map *threads,
                                      perf_event__handler_t process,
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 0f794744919c..bfa60bcafbde 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -750,6 +750,10 @@ int perf_event__process_exit(struct perf_tool *tool,
                             union perf_event *event,
                             struct perf_sample *sample,
                             struct machine *machine);
+int perf_tool__process_synth_event(struct perf_tool *tool,
+                                  union perf_event *event,
+                                  struct machine *machine,
+                                  perf_event__handler_t process);
 int perf_event__process(struct perf_tool *tool,
                        union perf_event *event,
                        struct perf_sample *sample,
@@ -796,6 +800,10 @@ int perf_event__synthesize_mmap_events(struct perf_tool 
*tool,
                                       bool mmap_data,
                                       unsigned int proc_map_timeout);
 
+int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
+                                      perf_event__handler_t process,
+                                      struct machine *machine);
+
 size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp);
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index a23aecc7328a..775889ae05b7 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1387,6 +1387,32 @@ static bool machine__uses_kcore(struct machine *machine)
        return false;
 }
 
+static bool perf_event__is_extra_kernel_mmap(struct machine *machine,
+                                            union perf_event *event)
+{
+       return machine__is(machine, "x86_64") &&
+              is_entry_trampoline(event->mmap.filename);
+}
+
+static int machine__process_extra_kernel_map(struct machine *machine,
+                                            union perf_event *event)
+{
+       struct map *kernel_map = machine__kernel_map(machine);
+       struct dso *kernel = kernel_map ? kernel_map->dso : NULL;
+       struct extra_kernel_map xm = {
+               .start = event->mmap.start,
+               .end   = event->mmap.start + event->mmap.len,
+               .pgoff = event->mmap.pgoff,
+       };
+
+       if (kernel == NULL)
+               return -1;
+
+       strlcpy(xm.name, event->mmap.filename, KMAP_NAME_LEN);
+
+       return machine__create_extra_kernel_map(machine, kernel, &xm);
+}
+
 static int machine__process_kernel_mmap_event(struct machine *machine,
                                              union perf_event *event)
 {
@@ -1490,6 +1516,8 @@ static int machine__process_kernel_mmap_event(struct 
machine *machine,
                         */
                        dso__load(kernel, machine__kernel_map(machine));
                }
+       } else if (perf_event__is_extra_kernel_mmap(machine, event)) {
+               return machine__process_extra_kernel_map(machine, event);
        }
        return 0;
 out_problem:
-- 
1.9.1

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