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Merge "Make ThreadLocalBuffer a class rather than a macro."

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This commit is contained in:
Elliott Hughes 2015-04-01 00:51:56 +00:00 committed by Gerrit Code Review
commit 72035734af
10 changed files with 86 additions and 90 deletions
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18
libc/bionic/libgen.cpp
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@ -36,6 +36,9 @@
#include "private/ThreadLocalBuffer.h"
static ThreadLocalBuffer<char, MAXPATHLEN> g_basename_tls_buffer;
static ThreadLocalBuffer<char, MAXPATHLEN> g_dirname_tls_buffer;
__LIBC64_HIDDEN__ int basename_r(const char* path, char* buffer, size_t buffer_size) {
const char* startp = NULL;
const char* endp = NULL;
@ -147,17 +150,14 @@ __LIBC64_HIDDEN__ int dirname_r(const char* path, char* buffer, size_t buffer_si
return result;
}
GLOBAL_INIT_THREAD_LOCAL_BUFFER(basename);
GLOBAL_INIT_THREAD_LOCAL_BUFFER(dirname);
char* basename(const char* path) {
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, basename, MAXPATHLEN);
int rc = basename_r(path, basename_tls_buffer, basename_tls_buffer_size);
return (rc < 0) ? NULL : basename_tls_buffer;
char* buf = g_basename_tls_buffer.get();
int rc = basename_r(path, buf, g_basename_tls_buffer.size());
return (rc < 0) ? NULL : buf;
}
char* dirname(const char* path) {
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, dirname, MAXPATHLEN);
int rc = dirname_r(path, dirname_tls_buffer, dirname_tls_buffer_size);
return (rc < 0) ? NULL : dirname_tls_buffer;
char* buf = g_dirname_tls_buffer.get();
int rc = dirname_r(path, buf, g_dirname_tls_buffer.size());
return (rc < 0) ? NULL : buf;
}

11
libc/bionic/mntent.cpp
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@ -31,14 +31,13 @@
#include "private/ThreadLocalBuffer.h"
GLOBAL_INIT_THREAD_LOCAL_BUFFER(getmntent_mntent);
GLOBAL_INIT_THREAD_LOCAL_BUFFER(getmntent_strings);
static ThreadLocalBuffer<mntent> g_getmntent_mntent_tls_buffer;
static ThreadLocalBuffer<char, BUFSIZ> g_getmntent_strings_tls_buffer;
mntent* getmntent(FILE* fp) {
LOCAL_INIT_THREAD_LOCAL_BUFFER(mntent*, getmntent_mntent, sizeof(mntent));
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, getmntent_strings, BUFSIZ);
return getmntent_r(fp, getmntent_mntent_tls_buffer,
getmntent_strings_tls_buffer, getmntent_strings_tls_buffer_size);
return getmntent_r(fp, g_getmntent_mntent_tls_buffer.get(),
g_getmntent_strings_tls_buffer.get(),
g_getmntent_strings_tls_buffer.size());
}
mntent* getmntent_r(FILE* fp, struct mntent* e, char* buf, int buf_len) {

16
libc/bionic/pty.cpp
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@ -38,8 +38,8 @@
#include "private/ThreadLocalBuffer.h"
GLOBAL_INIT_THREAD_LOCAL_BUFFER(ptsname);
GLOBAL_INIT_THREAD_LOCAL_BUFFER(ttyname);
static ThreadLocalBuffer<char, 32> g_ptsname_tls_buffer;
static ThreadLocalBuffer<char, 64> g_ttyname_tls_buffer;
int getpt() {
return posix_openpt(O_RDWR|O_NOCTTY);
@ -54,9 +54,9 @@ int posix_openpt(int flags) {
}
char* ptsname(int fd) {
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, ptsname, 32);
int error = ptsname_r(fd, ptsname_tls_buffer, ptsname_tls_buffer_size);
return (error == 0) ? ptsname_tls_buffer : NULL;
char* buf = g_ptsname_tls_buffer.get();
int error = ptsname_r(fd, buf, g_ptsname_tls_buffer.size());
return (error == 0) ? buf : NULL;
}
int ptsname_r(int fd, char* buf, size_t len) {
@ -80,9 +80,9 @@ int ptsname_r(int fd, char* buf, size_t len) {
}
char* ttyname(int fd) {
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, ttyname, 64);
int error = ttyname_r(fd, ttyname_tls_buffer, ttyname_tls_buffer_size);
return (error == 0) ? ttyname_tls_buffer : NULL;
char* buf = g_ttyname_tls_buffer.get();
int error = ttyname_r(fd, buf, g_ttyname_tls_buffer.size());
return (error == 0) ? buf : NULL;
}
int ttyname_r(int fd, char* buf, size_t len) {

10
libc/bionic/strerror.cpp
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@ -31,16 +31,16 @@
extern "C" const char* __strerror_lookup(int);
GLOBAL_INIT_THREAD_LOCAL_BUFFER(strerror);
static ThreadLocalBuffer<char, NL_TEXTMAX> g_strerror_tls_buffer;
char* strerror(int error_number) {
// Just return the original constant in the easy cases.
char* result = const_cast<char*>(__strerror_lookup(error_number));
if (result != NULL) {
if (result != nullptr) {
return result;
}
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, strerror, NL_TEXTMAX);
strerror_r(error_number, strerror_tls_buffer, strerror_tls_buffer_size);
return strerror_tls_buffer;
result = g_strerror_tls_buffer.get();
strerror_r(error_number, result, g_strerror_tls_buffer.size());
return result;
}

6
libc/bionic/strsignal.cpp
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@ -32,7 +32,7 @@
extern "C" const char* __strsignal_lookup(int);
extern "C" const char* __strsignal(int, char*, size_t);
GLOBAL_INIT_THREAD_LOCAL_BUFFER(strsignal);
static ThreadLocalBuffer<char, NL_TEXTMAX> g_strsignal_tls_buffer;
char* strsignal(int signal_number) {
// Just return the original constant in the easy cases.
@ -41,6 +41,6 @@ char* strsignal(int signal_number) {
return result;
}
LOCAL_INIT_THREAD_LOCAL_BUFFER(char*, strsignal, NL_TEXTMAX);
return const_cast<char*>(__strsignal(signal_number, strsignal_tls_buffer, strsignal_tls_buffer_size));
return const_cast<char*>(__strsignal(signal_number, g_strsignal_tls_buffer.get(),
g_strsignal_tls_buffer.size()));
}

30
libc/bionic/stubs.cpp
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@ -49,25 +49,12 @@
// functions to share state, but <grp.h> functions can't clobber <passwd.h>
// functions' state and vice versa.
GLOBAL_INIT_THREAD_LOCAL_BUFFER(group);
struct group_state_t {
group group_;
char* group_members_[2];
char group_name_buffer_[32];
};
static group_state_t* __group_state() {
LOCAL_INIT_THREAD_LOCAL_BUFFER(group_state_t*, group, sizeof(group_state_t));
if (group_tls_buffer != NULL) {
memset(group_tls_buffer, 0, sizeof(group_state_t));
group_tls_buffer->group_.gr_mem = group_tls_buffer->group_members_;
}
return group_tls_buffer;
}
GLOBAL_INIT_THREAD_LOCAL_BUFFER(passwd);
struct passwd_state_t {
passwd passwd_;
char name_buffer_[32];
@ -75,9 +62,16 @@ struct passwd_state_t {
char sh_buffer_[32];
};
static passwd_state_t* __passwd_state() {
LOCAL_INIT_THREAD_LOCAL_BUFFER(passwd_state_t*, passwd, sizeof(passwd_state_t));
return passwd_tls_buffer;
static ThreadLocalBuffer<group_state_t> g_group_tls_buffer;
static ThreadLocalBuffer<passwd_state_t> g_passwd_tls_buffer;
static group_state_t* __group_state() {
group_state_t* result = g_group_tls_buffer.get();
if (result != nullptr) {
memset(result, 0, sizeof(group_state_t));
result->group_.gr_mem = result->group_members_;
}
return result;
}
static int do_getpw_r(int by_name, const char* name, uid_t uid,
@ -361,7 +355,7 @@ static group* app_id_to_group(gid_t gid, group_state_t* state) {
}
passwd* getpwuid(uid_t uid) { // NOLINT: implementing bad function.
passwd_state_t* state = __passwd_state();
passwd_state_t* state = g_passwd_tls_buffer.get();
if (state == NULL) {
return NULL;
}
@ -374,7 +368,7 @@ passwd* getpwuid(uid_t uid) { // NOLINT: implementing bad function.
}
passwd* getpwnam(const char* login) { // NOLINT: implementing bad function.
passwd_state_t* state = __passwd_state();
passwd_state_t* state = g_passwd_tls_buffer.get();
if (state == NULL) {
return NULL;
}

8
libc/dns/resolv/res_state.c
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@ -39,8 +39,6 @@
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
#include <sys/_system_properties.h>
#include "private/ThreadLocalBuffer.h"
/* Set to 1 to enable debug traces */
#define DEBUG 0
@ -105,7 +103,11 @@ _res_thread_free( void* _rt )
free(rt);
}
BIONIC_PTHREAD_KEY_WITH_CONSTRUCTOR(_res_key, _res_thread_free);
static pthread_key_t _res_key;
__attribute__((constructor)) static void __res_key_init() {
pthread_key_create(&_res_key, _res_thread_free);
}
static _res_thread*
_res_thread_get(void)

40
libc/private/ThreadLocalBuffer.h
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@ -32,32 +32,30 @@
#include <malloc.h>
#include <pthread.h>
// libstdc++ currently contains __cxa_guard_acquire and __cxa_guard_release,
// so we make do with macros instead of a C++ class.
// TODO: move __cxa_guard_acquire and __cxa_guard_release into libc.
// TODO: use __thread instead?
template <typename T, size_t Size = sizeof(T)>
class ThreadLocalBuffer {
public:
ThreadLocalBuffer() {
// We used to use pthread_once to initialize the keys, but life is more predictable
// if we allocate them all up front when the C library starts up, via __constructor__.
#define BIONIC_PTHREAD_KEY_WITH_CONSTRUCTOR(key_name, key_destructor) \
static pthread_key_t key_name; \
__attribute__((constructor)) static void __bionic_tls_ ## key_name ## _key_init() { \
pthread_key_create(&key_name, key_destructor); \
pthread_key_create(&key_, free);
}
#define GLOBAL_INIT_THREAD_LOCAL_BUFFER(name) \
static void __bionic_tls_ ## name ## _key_destroy(void* buffer) { \
free(buffer); \
} \
BIONIC_PTHREAD_KEY_WITH_CONSTRUCTOR(__bionic_tls_ ## name ## _key, __bionic_tls_ ## name ## _key_destroy)
T* get() {
T* result = reinterpret_cast<T*>(pthread_getspecific(key_));
if (result == nullptr) {
result = reinterpret_cast<T*>(calloc(1, Size));
pthread_setspecific(key_, result);
}
return result;
}
// Leaves "name_tls_buffer" and "name_tls_buffer_size" defined and initialized.
#define LOCAL_INIT_THREAD_LOCAL_BUFFER(type, name, byte_count) \
type name ## _tls_buffer = \
reinterpret_cast<type>(pthread_getspecific(__bionic_tls_ ## name ## _key)); \
if (name ## _tls_buffer == NULL) { \
name ## _tls_buffer = reinterpret_cast<type>(calloc(1, byte_count)); \
pthread_setspecific(__bionic_tls_ ## name ## _key, name ## _tls_buffer); \
} \
const size_t name ## _tls_buffer_size __attribute__((unused)) = byte_count
size_t size() { return Size; }
private:
pthread_key_t key_;
};
#endif // _BIONIC_THREAD_LOCAL_BUFFER_H_included

30
libc/private/bionic_tls.h
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@ -72,22 +72,26 @@ enum {
/*
* Bionic uses some pthread keys internally. All pthread keys used internally
* should be created in constructors, except for keys that may be used in or before constructors.
* should be created in constructors, except for keys that may be used in or
* before constructors.
*
* We need to manually maintain the count of pthread keys used internally, but
* pthread_test should fail if we forget.
* Following are current pthread keys used internally by libc:
* basename libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* dirname libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
*
* These are the pthread keys currently used internally by libc:
*
* basename libc (ThreadLocalBuffer)
* dirname libc (ThreadLocalBuffer)
* uselocale libc (can be used in constructors)
* getmntent_mntent libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* getmntent_strings libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* ptsname libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* ttyname libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* strerror libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* strsignal libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* passwd libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* group libc (GLOBAL_INIT_THREAD_LOCAL_BUFFER)
* _res_key libc (BIONIC_PTHREAD_KEY_WITH_CONSTRUCTOR)
* getmntent_mntent libc (ThreadLocalBuffer)
* getmntent_strings libc (ThreadLocalBuffer)
* ptsname libc (ThreadLocalBuffer)
* ttyname libc (ThreadLocalBuffer)
* strerror libc (ThreadLocalBuffer)
* strsignal libc (ThreadLocalBuffer)
* passwd libc (ThreadLocalBuffer)
* group libc (ThreadLocalBuffer)
* _res_key libc (constructor in BSD code)
*/
#define LIBC_PTHREAD_KEY_RESERVED_COUNT 12

3
tests/pthread_test.cpp
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@ -68,8 +68,7 @@ TEST(pthread, pthread_key_many_distinct) {
for (int i = 0; i < nkeys; ++i) {
pthread_key_t key;
// If this fails, it's likely that GLOBAL_INIT_THREAD_LOCAL_BUFFER_COUNT is
// wrong.
// If this fails, it's likely that LIBC_PTHREAD_KEY_RESERVED_COUNT is wrong.
ASSERT_EQ(0, pthread_key_create(&key, NULL)) << i << " of " << nkeys;
keys.push_back(key);
ASSERT_EQ(0, pthread_setspecific(key, reinterpret_cast<void*>(i)));