Use the native tls implementation on android

Turns out android doesn't support LLVM's thread_local attribute and accompanying
implementation.

Closes #10686
This commit is contained in:
Alex Crichton 2013-11-26 20:23:56 -08:00
parent e4136bd552
commit 1686bfabf5
4 changed files with 235 additions and 256 deletions

View File

@ -132,7 +132,7 @@ mod test {
#[test]
fn thread_local_task_smoke_test() {
do run_in_bare_thread {
local_ptr::init_tls_key();
local_ptr::init();
let mut sched = ~new_test_uv_sched();
let task = ~Task::new_root(&mut sched.stack_pool, None, proc(){});
Local::put(task);
@ -144,7 +144,7 @@ mod test {
#[test]
fn thread_local_task_two_instances() {
do run_in_bare_thread {
local_ptr::init_tls_key();
local_ptr::init();
let mut sched = ~new_test_uv_sched();
let task = ~Task::new_root(&mut sched.stack_pool, None, proc(){});
Local::put(task);
@ -161,7 +161,7 @@ mod test {
#[test]
fn borrow_smoke_test() {
do run_in_bare_thread {
local_ptr::init_tls_key();
local_ptr::init();
let mut sched = ~new_test_uv_sched();
let task = ~Task::new_root(&mut sched.stack_pool, None, proc(){});
Local::put(task);
@ -177,7 +177,7 @@ mod test {
#[test]
fn borrow_with_return() {
do run_in_bare_thread {
local_ptr::init_tls_key();
local_ptr::init();
let mut sched = ~new_test_uv_sched();
let task = ~Task::new_root(&mut sched.stack_pool, None, proc(){});
Local::put(task);

View File

@ -15,183 +15,17 @@
//! XXX: Add runtime checks for usage of inconsistent pointer types.
//! and for overwriting an existing pointer.
use libc::c_void;
use cast;
#[cfg(stage0)]
#[cfg(windows)]
use ptr;
use cell::Cell;
use option::{Option, Some, None};
use unstable::finally::Finally;
#[cfg(stage0)]
#[cfg(windows)]
use unstable::mutex::{Mutex, MUTEX_INIT};
#[cfg(stage0)]
#[cfg(windows)]
use tls = rt::thread_local_storage;
#[cfg(not(stage0), not(windows), test)]
#[thread_local]
pub use realstd::rt::shouldnt_be_public::RT_TLS_PTR;
#[cfg(windows)] // mingw-w32 doesn't like thread_local things
#[cfg(target_os = "android")] // see #10686
#[cfg(stage0)] // only remove this attribute after the next snapshot
pub use self::native::*;
#[cfg(not(stage0), not(windows), not(test))]
#[thread_local]
pub static mut RT_TLS_PTR: *mut c_void = 0 as *mut c_void;
#[cfg(stage0)]
#[cfg(windows)]
static mut RT_TLS_KEY: tls::Key = -1;
#[cfg(stage0)]
#[cfg(windows)]
static mut tls_lock: Mutex = MUTEX_INIT;
static mut tls_initialized: bool = false;
/// Initialize the TLS key. Other ops will fail if this isn't executed first.
#[inline(never)]
#[cfg(stage0)]
#[cfg(windows)]
pub fn init_tls_key() {
unsafe {
tls_lock.lock();
if !tls_initialized {
tls::create(&mut RT_TLS_KEY);
tls_initialized = true;
}
tls_lock.unlock();
}
}
#[cfg(not(stage0), not(windows))]
pub fn init_tls_key() {
unsafe {
tls_initialized = true;
}
}
#[cfg(windows)]
pub unsafe fn cleanup() {
// No real use to acquiring a lock around these operations. All we're
// going to do is destroy the lock anyway which races locking itself. This
// is why the whole function is labeled as 'unsafe'
assert!(tls_initialized);
tls::destroy(RT_TLS_KEY);
tls_lock.destroy();
tls_initialized = false;
}
#[cfg(not(windows))]
pub unsafe fn cleanup() {
assert!(tls_initialized);
tls_initialized = false;
}
/// Give a pointer to thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
#[cfg(stage0)]
#[cfg(windows)]
pub unsafe fn put<T>(sched: ~T) {
let key = tls_key();
let void_ptr: *mut c_void = cast::transmute(sched);
tls::set(key, void_ptr);
}
/// Give a pointer to thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
#[cfg(not(stage0), not(windows))]
pub unsafe fn put<T>(sched: ~T) {
RT_TLS_PTR = cast::transmute(sched)
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
#[cfg(stage0)]
#[cfg(windows)]
pub unsafe fn take<T>() -> ~T {
let key = tls_key();
let void_ptr: *mut c_void = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
let ptr: ~T = cast::transmute(void_ptr);
tls::set(key, ptr::mut_null());
return ptr;
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
#[cfg(not(stage0), not(windows))]
pub unsafe fn take<T>() -> ~T {
let ptr: ~T = cast::transmute(RT_TLS_PTR);
RT_TLS_PTR = cast::transmute(0); // can't use `as`, due to type not matching with `cfg(test)`
ptr
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
/// Leaves the old pointer in TLS for speed.
#[inline]
#[cfg(stage0)]
#[cfg(windows)]
pub unsafe fn unsafe_take<T>() -> ~T {
let key = tls_key();
let void_ptr: *mut c_void = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
let ptr: ~T = cast::transmute(void_ptr);
return ptr;
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
/// Leaves the old pointer in TLS for speed.
#[inline]
#[cfg(not(stage0), not(windows))]
pub unsafe fn unsafe_take<T>() -> ~T {
cast::transmute(RT_TLS_PTR)
}
/// Check whether there is a thread-local pointer installed.
#[cfg(stage0)]
#[cfg(windows)]
pub fn exists() -> bool {
unsafe {
match maybe_tls_key() {
Some(key) => tls::get(key).is_not_null(),
None => false
}
}
}
/// Check whether there is a thread-local pointer installed.
#[cfg(not(stage0), not(windows))]
pub fn exists() -> bool {
unsafe {
RT_TLS_PTR.is_not_null()
}
}
#[cfg(not(stage0), not(windows), not(target_os = "android"))]
pub use self::compiled::*;
/// Borrow the thread-local value from thread-local storage.
/// While the value is borrowed it is not available in TLS.
@ -209,92 +43,239 @@ pub unsafe fn borrow<T>(f: |&mut T|) {
(|| f(unsafe_ptr)).finally(|| put(value_cell.take()));
}
/// Borrow a mutable reference to the thread-local value
///
/// # Safety Note
///
/// Because this leaves the value in thread-local storage it is possible
/// For the Scheduler pointer to be aliased
#[cfg(stage0)]
#[cfg(windows)]
pub unsafe fn unsafe_borrow<T>() -> *mut T {
let key = tls_key();
let void_ptr = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
/// Compiled implementation of accessing the runtime local pointer. This is
/// implemented using LLVM's thread_local attribute which isn't necessarily
/// working on all platforms. This implementation is faster, however, so we use
/// it wherever possible.
#[cfg(not(windows), not(target_os = "android"))]
pub mod compiled {
use libc::c_void;
use cast;
use option::{Option, Some, None};
#[cfg(test)]
pub use realstd::rt::shouldnt_be_public::RT_TLS_PTR;
#[cfg(not(test))]
#[thread_local]
pub static mut RT_TLS_PTR: *mut c_void = 0 as *mut c_void;
pub fn init() {}
pub unsafe fn cleanup() {}
/// Give a pointer to thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
pub unsafe fn put<T>(sched: ~T) {
RT_TLS_PTR = cast::transmute(sched)
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
pub unsafe fn take<T>() -> ~T {
let ptr: ~T = cast::transmute(RT_TLS_PTR);
// can't use `as`, due to type not matching with `cfg(test)`
RT_TLS_PTR = cast::transmute(0);
ptr
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
/// Leaves the old pointer in TLS for speed.
#[inline]
pub unsafe fn unsafe_take<T>() -> ~T {
cast::transmute(RT_TLS_PTR)
}
/// Check whether there is a thread-local pointer installed.
pub fn exists() -> bool {
unsafe {
RT_TLS_PTR.is_not_null()
}
}
pub unsafe fn unsafe_borrow<T>() -> *mut T {
if RT_TLS_PTR.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
RT_TLS_PTR as *mut T
}
pub unsafe fn try_unsafe_borrow<T>() -> Option<*mut T> {
if RT_TLS_PTR.is_null() {
None
} else {
Some(RT_TLS_PTR as *mut T)
}
}
void_ptr as *mut T
}
#[cfg(not(stage0), not(windows))]
pub unsafe fn unsafe_borrow<T>() -> *mut T {
if RT_TLS_PTR.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
RT_TLS_PTR as *mut T
}
/// Native implementation of having the runtime thread-local pointer. This
/// implementation uses the `thread_local_storage` module to provide a
/// thread-local value.
pub mod native {
use cast;
use libc::c_void;
use option::{Option, Some, None};
use ptr;
use tls = rt::thread_local_storage;
use unstable::mutex::{Mutex, MUTEX_INIT};
#[cfg(stage0)]
#[cfg(windows)]
pub unsafe fn try_unsafe_borrow<T>() -> Option<*mut T> {
match maybe_tls_key() {
Some(key) => {
let void_ptr = tls::get(key);
if void_ptr.is_null() {
None
} else {
Some(void_ptr as *mut T)
static mut LOCK: Mutex = MUTEX_INIT;
static mut INITIALIZED: bool = false;
static mut RT_TLS_KEY: tls::Key = -1;
/// Initialize the TLS key. Other ops will fail if this isn't executed
/// first.
pub fn init() {
unsafe {
LOCK.lock();
if !INITIALIZED {
tls::create(&mut RT_TLS_KEY);
INITIALIZED = true;
}
LOCK.unlock();
}
}
pub unsafe fn cleanup() {
assert!(INITIALIZED);
tls::destroy(RT_TLS_KEY);
LOCK.destroy();
INITIALIZED = false;
}
/// Give a pointer to thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
pub unsafe fn put<T>(sched: ~T) {
let key = tls_key();
let void_ptr: *mut c_void = cast::transmute(sched);
tls::set(key, void_ptr);
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
#[inline]
pub unsafe fn take<T>() -> ~T {
let key = tls_key();
let void_ptr: *mut c_void = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
let ptr: ~T = cast::transmute(void_ptr);
tls::set(key, ptr::mut_null());
return ptr;
}
/// Take ownership of a pointer from thread-local storage.
///
/// # Safety note
///
/// Does not validate the pointer type.
/// Leaves the old pointer in TLS for speed.
#[inline]
pub unsafe fn unsafe_take<T>() -> ~T {
let key = tls_key();
let void_ptr: *mut c_void = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
let ptr: ~T = cast::transmute(void_ptr);
return ptr;
}
/// Check whether there is a thread-local pointer installed.
pub fn exists() -> bool {
unsafe {
match maybe_tls_key() {
Some(key) => tls::get(key).is_not_null(),
None => false
}
}
None => None
}
}
#[cfg(not(stage0), not(windows))]
pub unsafe fn try_unsafe_borrow<T>() -> Option<*mut T> {
if RT_TLS_PTR.is_null() {
None
} else {
Some(RT_TLS_PTR as *mut T)
/// Borrow a mutable reference to the thread-local value
///
/// # Safety Note
///
/// Because this leaves the value in thread-local storage it is possible
/// For the Scheduler pointer to be aliased
pub unsafe fn unsafe_borrow<T>() -> *mut T {
let key = tls_key();
let void_ptr = tls::get(key);
if void_ptr.is_null() {
rtabort!("thread-local pointer is null. bogus!");
}
void_ptr as *mut T
}
}
#[inline]
#[cfg(stage0)]
#[cfg(windows)]
fn tls_key() -> tls::Key {
match maybe_tls_key() {
Some(key) => key,
None => rtabort!("runtime tls key not initialized")
pub unsafe fn try_unsafe_borrow<T>() -> Option<*mut T> {
match maybe_tls_key() {
Some(key) => {
let void_ptr = tls::get(key);
if void_ptr.is_null() {
None
} else {
Some(void_ptr as *mut T)
}
}
None => None
}
}
}
#[inline]
#[cfg(not(test), stage0)]
#[cfg(not(test), windows)]
pub fn maybe_tls_key() -> Option<tls::Key> {
unsafe {
// NB: This is a little racy because, while the key is
// initalized under a mutex and it's assumed to be initalized
// in the Scheduler ctor by any thread that needs to use it,
// we are not accessing the key under a mutex. Threads that
// are not using the new Scheduler but still *want to check*
// whether they are running under a new Scheduler may see a 0
// value here that is in the process of being initialized in
// another thread. I think this is fine since the only action
// they could take if it was initialized would be to check the
// thread-local value and see that it's not set.
if RT_TLS_KEY != -1 {
return Some(RT_TLS_KEY);
} else {
return None;
#[inline]
fn tls_key() -> tls::Key {
match maybe_tls_key() {
Some(key) => key,
None => rtabort!("runtime tls key not initialized")
}
}
#[inline]
#[cfg(not(test))]
pub fn maybe_tls_key() -> Option<tls::Key> {
unsafe {
// NB: This is a little racy because, while the key is
// initalized under a mutex and it's assumed to be initalized
// in the Scheduler ctor by any thread that needs to use it,
// we are not accessing the key under a mutex. Threads that
// are not using the new Scheduler but still *want to check*
// whether they are running under a new Scheduler may see a 0
// value here that is in the process of being initialized in
// another thread. I think this is fine since the only action
// they could take if it was initialized would be to check the
// thread-local value and see that it's not set.
if RT_TLS_KEY != -1 {
return Some(RT_TLS_KEY);
} else {
return None;
}
}
}
#[inline] #[cfg(test)]
pub fn maybe_tls_key() -> Option<tls::Key> {
use realstd;
unsafe {
cast::transmute(realstd::rt::shouldnt_be_public::maybe_tls_key())
}
}
}
#[inline]
#[cfg(test, stage0)]
#[cfg(test, windows)]
pub fn maybe_tls_key() -> Option<tls::Key> {
unsafe { ::cast::transmute(::realstd::rt::shouldnt_be_public::maybe_tls_key()) }
}

View File

@ -95,11 +95,9 @@ pub use self::kill::BlockedTask;
pub mod shouldnt_be_public {
pub use super::select::SelectInner;
pub use super::select::{SelectInner, SelectPortInner};
#[cfg(stage0)]
#[cfg(windows)]
pub use super::local_ptr::maybe_tls_key;
#[cfg(not(stage0), not(windows))]
pub use super::local_ptr::RT_TLS_PTR;
pub use super::local_ptr::native::maybe_tls_key;
#[cfg(not(stage0), not(windows), not(target_os = "android"))]
pub use super::local_ptr::compiled::RT_TLS_PTR;
}
// Internal macros used by the runtime.

View File

@ -172,7 +172,7 @@ impl Scheduler {
self.idle_callback = Some(self.event_loop.pausible_idle_callback(cb));
// Initialize the TLS key.
local_ptr::init_tls_key();
local_ptr::init();
// Create a task for the scheduler with an empty context.
let sched_task = ~Task::new_sched_task();