From 8077bf3d1067a52ad3f5dec2f86b8ef99bc811fe Mon Sep 17 00:00:00 2001 From: Sam Lantinga Date: Mon, 7 Jul 2014 21:27:42 -0700 Subject: [PATCH] Fixed bug 2618 - incomplete pthread-based lock support should be removed binarycrusader Since changeset 358696c354a8, SDL 2.0 has been broken on Solaris when compiling with the Solaris Studio compiler (which uses the pthread implementation of SDL_AtomicLock). Notably, it gets stuck at the MemoryBarrierRelease in SDL_GetErrBuf: 6585 # 218 6586 if (!tls_errbuf && !tls_being_created) { 6587 SDL_AtomicLock_REAL ( & tls_lock ); 6588 if (!tls_errbuf) { 6589 SDL_TLSID slot; 6590 tls_being_created = SDL_TRUE; 6591 slot = SDL_TLSCreate_REAL ( ); 6592 tls_being_created = SDL_FALSE; 6593 { SDL_SpinLock _tmp = 0 ; SDL_AtomicLock_REAL ( & _tmp ) ; SDL_AtomicUnlock_REAL ( & _tmp ) ; }; ^^^ loops forever above 6594 tls_errbuf = slot; 6595 } 6596 SDL_AtomicUnlock_REAL ( & tls_lock ); 6597 } Running: testthread (process id 28926) ^Cdbx: warning: Interrupt ignored but forwarded to child. signal INT (Interrupt) in __nanosleep at 0xfe52a875 0xfe52a875: __nanosleep+0x0015: jae __nanosleep+0x23 [ 0xfe52a883, .+0xe ] Current function is SDL_Delay_REAL 204 was_error = nanosleep(&tv, &elapsed); (dbx) where [1] __nanosleep(0xfeffe848, 0xfeffe850, 0xfe75a5ac, 0xfe5169d8), at 0xfe52a875 [2] nanosleep(0xfeffe848, 0xfeffe850), at 0xfe516a3b =>[3] SDL_Delay_REAL(ms = 0), line 204 in "SDL_systimer.c" [4] SDL_AtomicLock_REAL(lock = 0xfeffe88c), line 104 in "SDL_spinlock.c" [5] SDL_GetErrBuf(), line 225 in "SDL_thread.c" [6] SDL_ClearError_REAL(), line 216 in "SDL_error.c" [7] SDL_InitSubSystem_REAL(flags = 0), line 116 in "SDL.c" [8] SDL_Init_REAL(flags = 0), line 244 in "SDL.c" [9] SDL_Init(a = 0), line 89 in "SDL_dynapi_procs.h" [10] main(argc = 1, argv = 0xfeffe948), line 65 in "testthread.c" As far as I can tell, this is because pthread_spin_trylock() always returns EBUSY for this particular lock; since it works in other places, I'm suspicious. Different Solaris Studio compiler versions seem to make no difference. I've verified this is broken on Linux as well if SDL_spinlock.c is modified to use the pthread implementation. This appears to be because pthread_spin_init() and pthread_spin_destroy() are not used with the locks as required. --- cmake/sdlchecks.cmake | 7 ------- configure.in | 9 --------- include/SDL_config.h.cmake | 1 - include/SDL_config.h.in | 1 - premake/Linux/SDL_config_premake.h | 1 - premake/config/SDL_config_cygwin.template.h | 1 - premake/config/SDL_config_linux.template.h | 1 - src/atomic/SDL_spinlock.c | 7 ------- 8 files changed, 28 deletions(-) diff --git a/cmake/sdlchecks.cmake b/cmake/sdlchecks.cmake index 2cd09e6ff..08347ece2 100644 --- a/cmake/sdlchecks.cmake +++ b/cmake/sdlchecks.cmake @@ -753,13 +753,6 @@ macro(CheckPTHREAD) endif(HAVE_PTHREADS_SEM) endif(PTHREADS_SEM) - check_c_source_compiles(" - #include - int main(int argc, char** argv) { - pthread_spin_trylock(NULL); - return 0; - }" HAVE_PTHREAD_SPINLOCK) - check_c_source_compiles(" #include #include diff --git a/configure.in b/configure.in index d4c537eea..3c87ea754 100644 --- a/configure.in +++ b/configure.in @@ -2384,15 +2384,6 @@ AC_HELP_STRING([--enable-pthread-sem], [use pthread semaphores [[default=yes]]]) AC_MSG_RESULT($have_sem_timedwait) fi - AC_MSG_CHECKING(for pthread_spin_trylock) - AC_TRY_LINK_FUNC(pthread_spin_trylock, [ - has_pthread_spin_trylock=yes - AC_DEFINE(HAVE_PTHREAD_SPINLOCK, 1, [ ]) - ],[ - has_pthread_spin_trylock=no - ]) - AC_MSG_RESULT($has_pthread_spin_trylock) - AC_CHECK_HEADER(pthread_np.h, have_pthread_np_h=yes, have_pthread_np_h=no, [ #include ]) if test x$have_pthread_np_h = xyes; then AC_DEFINE(HAVE_PTHREAD_NP_H, 1, [ ]) diff --git a/include/SDL_config.h.cmake b/include/SDL_config.h.cmake index 2c9ce6c6c..9bcf6e909 100644 --- a/include/SDL_config.h.cmake +++ b/include/SDL_config.h.cmake @@ -46,7 +46,6 @@ #cmakedefine HAVE_GCC_ATOMICS @HAVE_GCC_ATOMICS@ #cmakedefine HAVE_GCC_SYNC_LOCK_TEST_AND_SET @HAVE_GCC_SYNC_LOCK_TEST_AND_SET@ -#cmakedefine HAVE_PTHREAD_SPINLOCK @HAVE_PTHREAD_SPINLOCK@ #cmakedefine HAVE_DXGI_H @HAVE_DXGI_H@ diff --git a/include/SDL_config.h.in b/include/SDL_config.h.in index ea25249ac..145a7b772 100644 --- a/include/SDL_config.h.in +++ b/include/SDL_config.h.in @@ -49,7 +49,6 @@ #endif #undef HAVE_GCC_ATOMICS #undef HAVE_GCC_SYNC_LOCK_TEST_AND_SET -#undef HAVE_PTHREAD_SPINLOCK #undef HAVE_DDRAW_H #undef HAVE_DINPUT_H diff --git a/premake/Linux/SDL_config_premake.h b/premake/Linux/SDL_config_premake.h index f76594a98..01a135800 100644 --- a/premake/Linux/SDL_config_premake.h +++ b/premake/Linux/SDL_config_premake.h @@ -50,7 +50,6 @@ #endif #define HAVE_GCC_ATOMICS 1 /* #undef HAVE_GCC_SYNC_LOCK_TEST_AND_SET */ -#define HAVE_PTHREAD_SPINLOCK 1 /* Comment this if you want to build without any C library requirements */ #define HAVE_LIBC 1 diff --git a/premake/config/SDL_config_cygwin.template.h b/premake/config/SDL_config_cygwin.template.h index 46d6f36b6..651989eb7 100644 --- a/premake/config/SDL_config_cygwin.template.h +++ b/premake/config/SDL_config_cygwin.template.h @@ -46,7 +46,6 @@ #define SIZEOF_VOIDP 4 #define HAVE_GCC_ATOMICS 1 /* #undef HAVE_GCC_SYNC_LOCK_TEST_AND_SET */ -#define HAVE_PTHREAD_SPINLOCK 1 /* Comment this if you want to build without any C library requirements */ #define HAVE_LIBC 0 diff --git a/premake/config/SDL_config_linux.template.h b/premake/config/SDL_config_linux.template.h index 7560a880b..8a62fdb99 100644 --- a/premake/config/SDL_config_linux.template.h +++ b/premake/config/SDL_config_linux.template.h @@ -50,7 +50,6 @@ #endif #define HAVE_GCC_ATOMICS 1 /* #undef HAVE_GCC_SYNC_LOCK_TEST_AND_SET */ -#define HAVE_PTHREAD_SPINLOCK 1 /* Comment this if you want to build without any C library requirements */ #define HAVE_LIBC 1 diff --git a/src/atomic/SDL_spinlock.c b/src/atomic/SDL_spinlock.c index 11aff019b..29b5190e5 100644 --- a/src/atomic/SDL_spinlock.c +++ b/src/atomic/SDL_spinlock.c @@ -89,10 +89,6 @@ SDL_AtomicTryLock(SDL_SpinLock *lock) /* Maybe used for PowerPC, but the Intel asm or gcc atomics are favored. */ return OSAtomicCompareAndSwap32Barrier(0, 1, lock); -#elif HAVE_PTHREAD_SPINLOCK - /* pthread instructions */ - return (pthread_spin_trylock(lock) == 0); - #elif defined(__SOLARIS__) && defined(_LP64) /* Used for Solaris with non-gcc compilers. */ return (SDL_bool) ((int) atomic_cas_64((volatile uint64_t*)lock, 0, 1) == 0); @@ -126,9 +122,6 @@ SDL_AtomicUnlock(SDL_SpinLock *lock) #elif HAVE_GCC_ATOMICS || HAVE_GCC_SYNC_LOCK_TEST_AND_SET __sync_lock_release(lock); -#elif HAVE_PTHREAD_SPINLOCK - pthread_spin_unlock(lock); - #elif defined(__SOLARIS__) /* Used for Solaris when not using gcc. */ *lock = 0;