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authorArnaldo Carvalho de Melo <acme@redhat.com>2009-12-11 17:50:36 +0100
committerIngo Molnar <mingo@elte.hu>2009-12-12 07:42:09 +0100
commit9958e1f0aee632c3665162c9c93cf8fde8006a94 (patch)
treeffd81c34d3ca8044c3fe0d670dc1786113624bbb
parentperf tools: Allow building for ARM (diff)
downloadlinux-9958e1f0aee632c3665162c9c93cf8fde8006a94.tar.xz
linux-9958e1f0aee632c3665162c9c93cf8fde8006a94.zip
perf symbols: Rename kthreads to kmaps, using another abstraction for it
Using a struct thread instance just to hold the kernel space maps (vmlinux + modules) is overkill and confuses people trying to understand the perf symbols abstractions. The kernel maps are really present in all threads, i.e. the kernel is a library, not a separate thread. So introduce the 'map_groups' abstraction and use it for the kernel maps, now in the kmaps global variable. It, in turn, will move, together with the threads list to the perf_file abstraction, so that we can support multiple perf_file instances, needed by perf diff. Brainstormed-with: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1260550239-5372-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r--tools/perf/builtin-kmem.c2
-rw-r--r--tools/perf/util/event.c11
-rw-r--r--tools/perf/util/symbol.c73
-rw-r--r--tools/perf/util/symbol.h4
-rw-r--r--tools/perf/util/thread.c62
-rw-r--r--tools/perf/util/thread.h39
6 files changed, 106 insertions, 85 deletions
diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 5f209514f657..fe73435192b3 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -403,7 +403,7 @@ static void __print_result(struct rb_root *root, int n_lines, int is_caller)
if (is_caller) {
addr = data->call_site;
if (!raw_ip)
- sym = thread__find_function(kthread, addr, NULL);
+ sym = map_groups__find_function(kmaps, addr, NULL);
} else
addr = data->ptr;
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 4dcecafa85dc..ba0de90cd3d4 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -254,13 +254,14 @@ void thread__find_addr_location(struct thread *self, u8 cpumode,
struct addr_location *al,
symbol_filter_t filter)
{
- struct thread *thread = al->thread = self;
+ struct map_groups *mg = &self->mg;
+ al->thread = self;
al->addr = addr;
if (cpumode & PERF_RECORD_MISC_KERNEL) {
al->level = 'k';
- thread = kthread;
+ mg = kmaps;
} else if (cpumode & PERF_RECORD_MISC_USER)
al->level = '.';
else {
@@ -270,7 +271,7 @@ void thread__find_addr_location(struct thread *self, u8 cpumode,
return;
}
try_again:
- al->map = thread__find_map(thread, type, al->addr);
+ al->map = map_groups__find(mg, type, al->addr);
if (al->map == NULL) {
/*
* If this is outside of all known maps, and is a negative
@@ -281,8 +282,8 @@ try_again:
* "[vdso]" dso, but for now lets use the old trick of looking
* in the whole kernel symbol list.
*/
- if ((long long)al->addr < 0 && thread != kthread) {
- thread = kthread;
+ if ((long long)al->addr < 0 && mg != kmaps) {
+ mg = kmaps;
goto try_again;
}
al->sym = NULL;
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index e7508ad3450f..936202342949 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -29,11 +29,11 @@ enum dso_origin {
};
static void dsos__add(struct list_head *head, struct dso *dso);
-static struct map *thread__find_map_by_name(struct thread *self, char *name);
+static struct map *map_groups__find_by_name(struct map_groups *self, char *name);
static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
struct symbol *dso__find_symbol(struct dso *self, enum map_type type, u64 addr);
static int dso__load_kernel_sym(struct dso *self, struct map *map,
- struct thread *thread, symbol_filter_t filter);
+ struct map_groups *mg, symbol_filter_t filter);
unsigned int symbol__priv_size;
static int vmlinux_path__nr_entries;
static char **vmlinux_path;
@@ -43,8 +43,8 @@ static struct symbol_conf symbol_conf__defaults = {
.try_vmlinux_path = true,
};
-static struct thread kthread_mem;
-struct thread *kthread = &kthread_mem;
+static struct map_groups kmaps_mem;
+struct map_groups *kmaps = &kmaps_mem;
bool dso__loaded(const struct dso *self, enum map_type type)
{
@@ -79,7 +79,7 @@ static void symbols__fixup_end(struct rb_root *self)
curr->end = roundup(curr->start, 4096);
}
-static void __thread__fixup_maps_end(struct thread *self, enum map_type type)
+static void __map_groups__fixup_end(struct map_groups *self, enum map_type type)
{
struct map *prev, *curr;
struct rb_node *nd, *prevnd = rb_first(&self->maps[type]);
@@ -102,11 +102,11 @@ static void __thread__fixup_maps_end(struct thread *self, enum map_type type)
curr->end = ~0UL;
}
-static void thread__fixup_maps_end(struct thread *self)
+static void map_groups__fixup_end(struct map_groups *self)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
- __thread__fixup_maps_end(self, i);
+ __map_groups__fixup_end(self, i);
}
static struct symbol *symbol__new(u64 start, u64 len, const char *name)
@@ -364,8 +364,8 @@ out_failure:
* kernel range is broken in several maps, named [kernel].N, as we don't have
* the original ELF section names vmlinux have.
*/
-static int dso__split_kallsyms(struct dso *self, struct map *map, struct thread *thread,
- symbol_filter_t filter)
+static int dso__split_kallsyms(struct dso *self, struct map *map,
+ struct map_groups *mg, symbol_filter_t filter)
{
struct map *curr_map = map;
struct symbol *pos;
@@ -382,13 +382,13 @@ static int dso__split_kallsyms(struct dso *self, struct map *map, struct thread
module = strchr(pos->name, '\t');
if (module) {
- if (!thread->use_modules)
+ if (!mg->use_modules)
goto discard_symbol;
*module++ = '\0';
if (strcmp(self->name, module)) {
- curr_map = thread__find_map_by_name(thread, module);
+ curr_map = map_groups__find_by_name(mg, module);
if (curr_map == NULL) {
pr_debug("/proc/{kallsyms,modules} "
"inconsistency!\n");
@@ -419,7 +419,7 @@ static int dso__split_kallsyms(struct dso *self, struct map *map, struct thread
}
curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
- __thread__insert_map(thread, curr_map);
+ map_groups__insert(mg, curr_map);
++kernel_range;
}
@@ -440,7 +440,7 @@ discard_symbol: rb_erase(&pos->rb_node, root);
static int dso__load_kallsyms(struct dso *self, struct map *map,
- struct thread *thread, symbol_filter_t filter)
+ struct map_groups *mg, symbol_filter_t filter)
{
if (dso__load_all_kallsyms(self, map) < 0)
return -1;
@@ -448,13 +448,13 @@ static int dso__load_kallsyms(struct dso *self, struct map *map,
symbols__fixup_end(&self->symbols[map->type]);
self->origin = DSO__ORIG_KERNEL;
- return dso__split_kallsyms(self, map, thread, filter);
+ return dso__split_kallsyms(self, map, mg, filter);
}
size_t kernel_maps__fprintf(FILE *fp)
{
size_t printed = fprintf(fp, "Kernel maps:\n");
- printed += thread__fprintf_maps(kthread, fp);
+ printed += map_groups__fprintf_maps(kmaps, fp);
return printed + fprintf(fp, "END kernel maps\n");
}
@@ -745,7 +745,7 @@ out:
}
static int dso__load_sym(struct dso *self, struct map *map,
- struct thread *thread, const char *name, int fd,
+ struct map_groups *mg, const char *name, int fd,
symbol_filter_t filter, int kernel, int kmodule)
{
struct map *curr_map = map;
@@ -849,7 +849,7 @@ static int dso__load_sym(struct dso *self, struct map *map,
snprintf(dso_name, sizeof(dso_name),
"%s%s", self->short_name, section_name);
- curr_map = thread__find_map_by_name(thread, dso_name);
+ curr_map = map_groups__find_by_name(mg, dso_name);
if (curr_map == NULL) {
u64 start = sym.st_value;
@@ -868,7 +868,7 @@ static int dso__load_sym(struct dso *self, struct map *map,
curr_map->map_ip = identity__map_ip;
curr_map->unmap_ip = identity__map_ip;
curr_dso->origin = DSO__ORIG_KERNEL;
- __thread__insert_map(kthread, curr_map);
+ map_groups__insert(kmaps, curr_map);
dsos__add(&dsos__kernel, curr_dso);
} else
curr_dso = curr_map->dso;
@@ -1094,7 +1094,7 @@ int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
dso__set_loaded(self, map->type);
if (self->kernel)
- return dso__load_kernel_sym(self, map, kthread, filter);
+ return dso__load_kernel_sym(self, map, kmaps, filter);
name = malloc(size);
if (!name)
@@ -1180,7 +1180,7 @@ out:
return ret;
}
-static struct map *thread__find_map_by_name(struct thread *self, char *name)
+static struct map *map_groups__find_by_name(struct map_groups *self, char *name)
{
struct rb_node *nd;
@@ -1228,7 +1228,7 @@ static int dsos__set_modules_path_dir(char *dirname)
(int)(dot - dent->d_name), dent->d_name);
strxfrchar(dso_name, '-', '_');
- map = thread__find_map_by_name(kthread, dso_name);
+ map = map_groups__find_by_name(kmaps, dso_name);
if (map == NULL)
continue;
@@ -1281,7 +1281,7 @@ static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
return self;
}
-static int thread__create_module_maps(struct thread *self)
+static int map_groups__create_module_maps(struct map_groups *self)
{
char *line = NULL;
size_t n;
@@ -1338,7 +1338,7 @@ static int thread__create_module_maps(struct thread *self)
dso->has_build_id = true;
dso->origin = DSO__ORIG_KMODULE;
- __thread__insert_map(self, map);
+ map_groups__insert(self, map);
dsos__add(&dsos__kernel, dso);
}
@@ -1353,7 +1353,8 @@ out_failure:
return -1;
}
-static int dso__load_vmlinux(struct dso *self, struct map *map, struct thread *thread,
+static int dso__load_vmlinux(struct dso *self, struct map *map,
+ struct map_groups *mg,
const char *vmlinux, symbol_filter_t filter)
{
int err = -1, fd;
@@ -1387,14 +1388,14 @@ static int dso__load_vmlinux(struct dso *self, struct map *map, struct thread *t
return -1;
dso__set_loaded(self, map->type);
- err = dso__load_sym(self, map, thread, self->long_name, fd, filter, 1, 0);
+ err = dso__load_sym(self, map, mg, self->long_name, fd, filter, 1, 0);
close(fd);
return err;
}
static int dso__load_kernel_sym(struct dso *self, struct map *map,
- struct thread *thread, symbol_filter_t filter)
+ struct map_groups *mg, symbol_filter_t filter)
{
int err;
bool is_kallsyms;
@@ -1404,7 +1405,7 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map,
pr_debug("Looking at the vmlinux_path (%d entries long)\n",
vmlinux_path__nr_entries);
for (i = 0; i < vmlinux_path__nr_entries; ++i) {
- err = dso__load_vmlinux(self, map, thread,
+ err = dso__load_vmlinux(self, map, mg,
vmlinux_path[i], filter);
if (err > 0) {
pr_debug("Using %s for symbols\n",
@@ -1420,12 +1421,12 @@ static int dso__load_kernel_sym(struct dso *self, struct map *map,
if (is_kallsyms)
goto do_kallsyms;
- err = dso__load_vmlinux(self, map, thread, self->long_name, filter);
+ err = dso__load_vmlinux(self, map, mg, self->long_name, filter);
if (err <= 0) {
pr_info("The file %s cannot be used, "
"trying to use /proc/kallsyms...", self->long_name);
do_kallsyms:
- err = dso__load_kallsyms(self, map, thread, filter);
+ err = dso__load_kallsyms(self, map, mg, filter);
if (err > 0 && !is_kallsyms)
dso__set_long_name(self, strdup("[kernel.kallsyms]"));
}
@@ -1508,7 +1509,7 @@ size_t dsos__fprintf_buildid(FILE *fp)
__dsos__fprintf_buildid(&dsos__user, fp));
}
-static int thread__create_kernel_map(struct thread *self, const char *vmlinux)
+static int map_groups__create_kernel_map(struct map_groups *self, const char *vmlinux)
{
struct map *kmap;
struct dso *kernel = dso__new(vmlinux ?: "[kernel.kallsyms]");
@@ -1533,7 +1534,7 @@ static int thread__create_kernel_map(struct thread *self, const char *vmlinux)
sizeof(kernel->build_id)) == 0)
kernel->has_build_id = true;
- __thread__insert_map(self, kmap);
+ map_groups__insert(self, kmap);
dsos__add(&dsos__kernel, kernel);
dsos__add(&dsos__user, vdso);
@@ -1607,23 +1608,23 @@ int symbol__init(struct symbol_conf *conf)
elf_version(EV_CURRENT);
symbol__priv_size = pconf->priv_size;
- thread__init(kthread, 0);
+ map_groups__init(kmaps);
if (pconf->try_vmlinux_path && vmlinux_path__init() < 0)
return -1;
- if (thread__create_kernel_map(kthread, pconf->vmlinux_name) < 0) {
+ if (map_groups__create_kernel_map(kmaps, pconf->vmlinux_name) < 0) {
vmlinux_path__exit();
return -1;
}
- kthread->use_modules = pconf->use_modules;
- if (pconf->use_modules && thread__create_module_maps(kthread) < 0)
+ kmaps->use_modules = pconf->use_modules;
+ if (pconf->use_modules && map_groups__create_module_maps(kmaps) < 0)
pr_debug("Failed to load list of modules in use, "
"continuing...\n");
/*
* Now that we have all the maps created, just set the ->end of them:
*/
- thread__fixup_maps_end(kthread);
+ map_groups__fixup_end(kmaps);
return 0;
}
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index 17003efa0b39..6e1da1ea6311 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -113,8 +113,8 @@ size_t kernel_maps__fprintf(FILE *fp);
int symbol__init(struct symbol_conf *conf);
-struct thread;
-struct thread *kthread;
+struct map_groups;
+struct map_groups *kmaps;
extern struct list_head dsos__user, dsos__kernel;
extern struct dso *vdso;
#endif /* __PERF_SYMBOL */
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 603f5610861b..a1285129c831 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -9,11 +9,9 @@
static struct rb_root threads;
static struct thread *last_match;
-void thread__init(struct thread *self, pid_t pid)
+void map_groups__init(struct map_groups *self)
{
int i;
- self->pid = pid;
- self->comm = NULL;
for (i = 0; i < MAP__NR_TYPES; ++i) {
self->maps[i] = RB_ROOT;
INIT_LIST_HEAD(&self->removed_maps[i]);
@@ -25,7 +23,8 @@ static struct thread *thread__new(pid_t pid)
struct thread *self = zalloc(sizeof(*self));
if (self != NULL) {
- thread__init(self, pid);
+ map_groups__init(&self->mg);
+ self->pid = pid;
self->comm = malloc(32);
if (self->comm)
snprintf(self->comm, 32, ":%d", self->pid);
@@ -57,8 +56,8 @@ static const char *map_type__name[MAP__NR_TYPES] = {
[MAP__FUNCTION] = "Functions",
};
-static size_t __thread__fprintf_maps(struct thread *self,
- enum map_type type, FILE *fp)
+static size_t __map_groups__fprintf_maps(struct map_groups *self,
+ enum map_type type, FILE *fp)
{
size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
struct rb_node *nd;
@@ -76,16 +75,16 @@ static size_t __thread__fprintf_maps(struct thread *self,
return printed;
}
-size_t thread__fprintf_maps(struct thread *self, FILE *fp)
+size_t map_groups__fprintf_maps(struct map_groups *self, FILE *fp)
{
size_t printed = 0, i;
for (i = 0; i < MAP__NR_TYPES; ++i)
- printed += __thread__fprintf_maps(self, i, fp);
+ printed += __map_groups__fprintf_maps(self, i, fp);
return printed;
}
-static size_t __thread__fprintf_removed_maps(struct thread *self,
- enum map_type type, FILE *fp)
+static size_t __map_groups__fprintf_removed_maps(struct map_groups *self,
+ enum map_type type, FILE *fp)
{
struct map *pos;
size_t printed = 0;
@@ -101,20 +100,25 @@ static size_t __thread__fprintf_removed_maps(struct thread *self,
return printed;
}
-static size_t thread__fprintf_removed_maps(struct thread *self, FILE *fp)
+static size_t map_groups__fprintf_removed_maps(struct map_groups *self, FILE *fp)
{
size_t printed = 0, i;
for (i = 0; i < MAP__NR_TYPES; ++i)
- printed += __thread__fprintf_removed_maps(self, i, fp);
+ printed += __map_groups__fprintf_removed_maps(self, i, fp);
return printed;
}
-static size_t thread__fprintf(struct thread *self, FILE *fp)
+static size_t map_groups__fprintf(struct map_groups *self, FILE *fp)
{
- size_t printed = fprintf(fp, "Thread %d %s\n", self->pid, self->comm);
- printed += thread__fprintf_removed_maps(self, fp);
+ size_t printed = map_groups__fprintf_maps(self, fp);
printed += fprintf(fp, "Removed maps:\n");
- return printed + thread__fprintf_removed_maps(self, fp);
+ return printed + map_groups__fprintf_removed_maps(self, fp);
+}
+
+static size_t thread__fprintf(struct thread *self, FILE *fp)
+{
+ return fprintf(fp, "Thread %d %s\n", self->pid, self->comm) +
+ map_groups__fprintf(&self->mg, fp);
}
struct thread *threads__findnew(pid_t pid)
@@ -168,7 +172,8 @@ struct thread *register_idle_thread(void)
return thread;
}
-static void thread__remove_overlappings(struct thread *self, struct map *map)
+static void map_groups__remove_overlappings(struct map_groups *self,
+ struct map *map)
{
struct rb_root *root = &self->maps[map->type];
struct rb_node *next = rb_first(root);
@@ -238,12 +243,15 @@ struct map *maps__find(struct rb_root *maps, u64 ip)
void thread__insert_map(struct thread *self, struct map *map)
{
- thread__remove_overlappings(self, map);
- maps__insert(&self->maps[map->type], map);
+ map_groups__remove_overlappings(&self->mg, map);
+ map_groups__insert(&self->mg, map);
}
-static int thread__clone_maps(struct thread *self, struct thread *parent,
- enum map_type type)
+/*
+ * XXX This should not really _copy_ te maps, but refcount them.
+ */
+static int map_groups__clone(struct map_groups *self,
+ struct map_groups *parent, enum map_type type)
{
struct rb_node *nd;
for (nd = rb_first(&parent->maps[type]); nd; nd = rb_next(nd)) {
@@ -251,7 +259,7 @@ static int thread__clone_maps(struct thread *self, struct thread *parent,
struct map *new = map__clone(map);
if (new == NULL)
return -ENOMEM;
- thread__insert_map(self, new);
+ map_groups__insert(self, new);
}
return 0;
}
@@ -267,7 +275,7 @@ int thread__fork(struct thread *self, struct thread *parent)
return -ENOMEM;
for (i = 0; i < MAP__NR_TYPES; ++i)
- if (thread__clone_maps(self, parent, i) < 0)
+ if (map_groups__clone(&self->mg, &parent->mg, i) < 0)
return -ENOMEM;
return 0;
}
@@ -286,11 +294,11 @@ size_t threads__fprintf(FILE *fp)
return ret;
}
-struct symbol *thread__find_symbol(struct thread *self,
- enum map_type type, u64 addr,
- symbol_filter_t filter)
+struct symbol *map_groups__find_symbol(struct map_groups *self,
+ enum map_type type, u64 addr,
+ symbol_filter_t filter)
{
- struct map *map = thread__find_map(self, type, addr);
+ struct map *map = map_groups__find(self, type, addr);
if (map != NULL)
return map__find_symbol(map, map->map_ip(map, addr), filter);
diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index 686d6e914d9e..a6333f3716af 100644
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -5,52 +5,63 @@
#include <unistd.h>
#include "symbol.h"
-struct thread {
- struct rb_node rb_node;
+struct map_groups {
struct rb_root maps[MAP__NR_TYPES];
struct list_head removed_maps[MAP__NR_TYPES];
- pid_t pid;
bool use_modules;
+};
+
+struct thread {
+ struct rb_node rb_node;
+ struct map_groups mg;
+ pid_t pid;
char shortname[3];
char *comm;
int comm_len;
};
-void thread__init(struct thread *self, pid_t pid);
+void map_groups__init(struct map_groups *self);
int thread__set_comm(struct thread *self, const char *comm);
int thread__comm_len(struct thread *self);
struct thread *threads__findnew(pid_t pid);
struct thread *register_idle_thread(void);
void thread__insert_map(struct thread *self, struct map *map);
int thread__fork(struct thread *self, struct thread *parent);
-size_t thread__fprintf_maps(struct thread *self, FILE *fp);
+size_t map_groups__fprintf_maps(struct map_groups *self, FILE *fp);
size_t threads__fprintf(FILE *fp);
void maps__insert(struct rb_root *maps, struct map *map);
struct map *maps__find(struct rb_root *maps, u64 addr);
-static inline struct map *thread__find_map(struct thread *self,
+static inline void map_groups__insert(struct map_groups *self, struct map *map)
+{
+ maps__insert(&self->maps[map->type], map);
+}
+
+static inline struct map *map_groups__find(struct map_groups *self,
enum map_type type, u64 addr)
{
- return self ? maps__find(&self->maps[type], addr) : NULL;
+ return maps__find(&self->maps[type], addr);
}
-static inline void __thread__insert_map(struct thread *self, struct map *map)
+static inline struct map *thread__find_map(struct thread *self,
+ enum map_type type, u64 addr)
{
- maps__insert(&self->maps[map->type], map);
+ return self ? map_groups__find(&self->mg, type, addr) : NULL;
}
void thread__find_addr_location(struct thread *self, u8 cpumode,
enum map_type type, u64 addr,
struct addr_location *al,
symbol_filter_t filter);
-struct symbol *thread__find_symbol(struct thread *self,
- enum map_type type, u64 addr,
- symbol_filter_t filter);
+struct symbol *map_groups__find_symbol(struct map_groups *self,
+ enum map_type type, u64 addr,
+ symbol_filter_t filter);
static inline struct symbol *
-thread__find_function(struct thread *self, u64 addr, symbol_filter_t filter)
+map_groups__find_function(struct map_groups *self, u64 addr,
+ symbol_filter_t filter)
{
- return thread__find_symbol(self, MAP__FUNCTION, addr, filter);
+ return map_groups__find_symbol(self, MAP__FUNCTION, addr, filter);
}
#endif /* __PERF_THREAD_H */