int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
perf_event__handler_t process,
struct machine *machine)
{
size_t size;
const char *mmap_name;
char name_buff[PATH_MAX];
struct map *map = machine__kernel_map(machine);
struct kmap *kmap;
int err;
union perf_event *event;
if (symbol_conf.kptr_restrict)
return -1;
if (map == NULL)
return -1;
/*
* We should get this from /sys/kernel/sections/.text, but till that is
* available use this, and after it is use this as a fallback for older
* kernels.
*/
event = zalloc((sizeof(event->mmap) + machine->id_hdr_size));
if (event == NULL) {
pr_debug("Not enough memory synthesizing mmap event "
"for kernel modules\n");
return -1;
}
mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
if (machine__is_host(machine)) {
/*
* kernel uses PERF_RECORD_MISC_USER for user space maps,
* see kernel/perf_event.c __perf_event_mmap
*/
event->header.misc = PERF_RECORD_MISC_KERNEL;
} else {
event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
}
kmap = map__kmap(map);
size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
"%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1;
size = PERF_ALIGN(size, sizeof(u64));
event->mmap.header.type = PERF_RECORD_MMAP;
event->mmap.header.size = (sizeof(event->mmap) -
(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
event->mmap.pgoff = kmap->ref_reloc_sym->addr;
event->mmap.start = map->start;
event->mmap.len = map->end - event->mmap.start;
event->mmap.pid = machine->pid;
err = perf_tool__process_synth_event(tool, event, machine, process);
free(event);
return err;
}
int event__synthesize_kernel_mmap(event__handler_t process,
struct perf_session *session,
struct machine *machine,
const char *symbol_name)
{
size_t size;
const char *filename, *mmap_name;
char path[PATH_MAX];
char name_buff[PATH_MAX];
struct map *map;
event_t ev = {
.header = {
.type = PERF_RECORD_MMAP,
},
};
/*
* We should get this from /sys/kernel/sections/.text, but till that is
* available use this, and after it is use this as a fallback for older
* kernels.
*/
struct process_symbol_args args = { .name = symbol_name, };
mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
if (machine__is_host(machine)) {
/*
* kernel uses PERF_RECORD_MISC_USER for user space maps,
* see kernel/perf_event.c __perf_event_mmap
*/
ev.header.misc = PERF_RECORD_MISC_KERNEL;
filename = "/proc/kallsyms";
} else {
ev.header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
if (machine__is_default_guest(machine))
filename = (char *) symbol_conf.default_guest_kallsyms;
else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
filename = path;
}
}
if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0)
return -ENOENT;
map = machine->vmlinux_maps[MAP__FUNCTION];
size = snprintf(ev.mmap.filename, sizeof(ev.mmap.filename),
"%s%s", mmap_name, symbol_name) + 1;
size = ALIGN(size, sizeof(u64));
ev.mmap.header.size = (sizeof(ev.mmap) -
(sizeof(ev.mmap.filename) - size));
ev.mmap.pgoff = args.start;
ev.mmap.start = map->start;
ev.mmap.len = map->end - ev.mmap.start;
ev.mmap.pid = machine->pid;
return process(&ev, session);
}
int perf_event__synthesize_kernel_mmap(perf_event__handler_t process,
struct perf_session *session,
struct machine *machine,
const char *symbol_name)
{
size_t size;
const char *filename, *mmap_name;
char path[PATH_MAX];
char name_buff[PATH_MAX];
struct map *map;
int err;
/*
* We should get this from /sys/kernel/sections/.text, but till that is
* available use this, and after it is use this as a fallback for older
* kernels.
*/
struct process_symbol_args args = { .name = symbol_name, };
union perf_event *event = zalloc((sizeof(event->mmap) +
session->id_hdr_size));
if (event == NULL) {
pr_debug("Not enough memory synthesizing mmap event "
"for kernel modules\n");
return -1;
}
mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
if (machine__is_host(machine)) {
/*
* kernel uses PERF_RECORD_MISC_USER for user space maps,
* see kernel/perf_event.c __perf_event_mmap
*/
event->header.misc = PERF_RECORD_MISC_KERNEL;
filename = "/proc/kallsyms";
} else {
event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
if (machine__is_default_guest(machine))
filename = (char *) symbol_conf.default_guest_kallsyms;
else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
filename = path;
}
}
if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0)
return -ENOENT;
map = machine->vmlinux_maps[MAP__FUNCTION];
size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
"%s%s", mmap_name, symbol_name) + 1;
size = ALIGN(size, sizeof(u64));
event->mmap.header.type = PERF_RECORD_MMAP;
event->mmap.header.size = (sizeof(event->mmap) -
(sizeof(event->mmap.filename) - size) + session->id_hdr_size);
event->mmap.pgoff = args.start;
event->mmap.start = map->start;
event->mmap.len = map->end - event->mmap.start;
event->mmap.pid = machine->pid;
err = process(event, &synth_sample, session);
free(event);
return err;
}
static int event__process_kernel_mmap(event_t *self,
struct perf_session *session)
{
struct map *map;
char kmmap_prefix[PATH_MAX];
struct machine *machine;
enum dso_kernel_type kernel_type;
bool is_kernel_mmap;
machine = perf_session__findnew_machine(session, self->mmap.pid);
if (!machine) {
pr_err("Can't find id %d's machine\n", self->mmap.pid);
goto out_problem;
}
machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
if (machine__is_host(machine))
kernel_type = DSO_TYPE_KERNEL;
else
kernel_type = DSO_TYPE_GUEST_KERNEL;
is_kernel_mmap = memcmp(self->mmap.filename,
kmmap_prefix,
strlen(kmmap_prefix)) == 0;
if (self->mmap.filename[0] == '/' ||
(!is_kernel_mmap && self->mmap.filename[0] == '[')) {
char short_module_name[1024];
char *name, *dot;
if (self->mmap.filename[0] == '/') {
name = strrchr(self->mmap.filename, '/');
if (name == NULL)
goto out_problem;
++name; /* skip / */
dot = strrchr(name, '.');
if (dot == NULL)
goto out_problem;
snprintf(short_module_name, sizeof(short_module_name),
"[%.*s]", (int)(dot - name), name);
strxfrchar(short_module_name, '-', '_');
} else
strcpy(short_module_name, self->mmap.filename);
map = machine__new_module(machine, self->mmap.start,
self->mmap.filename);
if (map == NULL)
goto out_problem;
name = strdup(short_module_name);
if (name == NULL)
goto out_problem;
map->dso->short_name = name;
map->end = map->start + self->mmap.len;
} else if (is_kernel_mmap) {
const char *symbol_name = (self->mmap.filename +
strlen(kmmap_prefix));
/*
* Should be there already, from the build-id table in
* the header.
*/
struct dso *kernel = __dsos__findnew(&machine->kernel_dsos,
kmmap_prefix);
if (kernel == NULL)
goto out_problem;
kernel->kernel = kernel_type;
if (__machine__create_kernel_maps(machine, kernel) < 0)
goto out_problem;
event_set_kernel_mmap_len(machine->vmlinux_maps, self);
perf_session__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
symbol_name,
self->mmap.pgoff);
if (machine__is_default_guest(machine)) {
/*
* preload dso of guest kernel and modules
*/
dso__load(kernel, machine->vmlinux_maps[MAP__FUNCTION],
NULL);
}
}
return 0;
out_problem:
return -1;
}
