From 25fe93f0a11e6f4c8d470441ff91b9cddf7b3023 Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Wed, 13 Apr 2005 20:59:15 +0000 Subject: Add TLS support to libGL and, by virtue of using glthread.h and GL_CALL, all DRI drivers. A TLS enabled libGL can load a TLS or a non-TLS DRI driver, but a TLS DRI driver requires a TLS enabled libGL. This fixes bug #1822. --- src/mesa/glapi/glapi.c | 199 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 148 insertions(+), 51 deletions(-) (limited to 'src/mesa/glapi/glapi.c') diff --git a/src/mesa/glapi/glapi.c b/src/mesa/glapi/glapi.c index bbc0a9608d..8ed833042b 100644 --- a/src/mesa/glapi/glapi.c +++ b/src/mesa/glapi/glapi.c @@ -61,6 +61,10 @@ static GLboolean WarnFlag = GL_FALSE; static _glapi_warning_func warning_func; +static void init_glapi_relocs(void); + +static _glapi_proc generate_entrypoint(GLuint functionOffset); +static void fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset); /* * Enable/disable printing of warning messages. @@ -133,6 +137,28 @@ static GLint NoOpUnused(void) #if defined(THREADS) +#if defined(GLX_USE_TLS) + +__thread struct _glapi_table * _glapi_tls_Dispatch + __attribute__((tls_model("initial-exec"))) + = (struct _glapi_table *) __glapi_noop_table; + +static __thread struct _glapi_table * _glapi_tls_RealDispatch + __attribute__((tls_model("initial-exec"))) + = (struct _glapi_table *) __glapi_noop_table; + +__thread void * _glapi_tls_Context + __attribute__((tls_model("initial-exec"))); + +/** + * Legacy per-thread dispatch pointer. This is only needed to support + * non-TLS DRI drivers. + */ + +_glthread_TSD _gl_DispatchTSD; + +#else + /** * \name Multi-threaded control support variables * @@ -166,6 +192,7 @@ static _glthread_TSD RealDispatchTSD; /**< only when using override */ static _glthread_TSD ContextTSD; /**< Per-thread context pointer */ /*@}*/ +#endif /* defined(GLX_USE_TLS) */ #define DISPATCH_TABLE_NAME __glapi_threadsafe_table #define UNUSED_TABLE_NAME __unused_threadsafe_functions @@ -184,6 +211,29 @@ static GLint glUnused(void) /***** END THREAD-SAFE DISPATCH *****/ +#if defined(GLX_USE_TLS) + +/** + * \name Old dispatch pointers + * + * Very old DRI based drivers assume that \c _glapi_Dispatch will never be + * \c NULL. Becuase of that, special "thread-safe" dispatch functions are + * needed here. Slightly more recent drivers detect the multi-threaded case + * by \c _glapi_DispatchTSD being \c NULL. + * + * \deprecated + * + * \warning + * \c _glapi_RealDispatch does not exist in TLS builds. I don't think it was + * ever used outside libGL.so, so this should be safe. + */ +/*@{*/ +PUBLIC const struct _glapi_table *_glapi_Dispatch = (struct _glapi_table *) __glapi_threadsafe_table; +PUBLIC const struct _glapi_table *_glapi_DispatchTSD = NULL; +PUBLIC const void *_glapi_Context = NULL; +/*@}*/ + +#else PUBLIC struct _glapi_table *_glapi_Dispatch = (struct _glapi_table *) __glapi_noop_table; #if defined( THREADS ) @@ -191,10 +241,11 @@ PUBLIC struct _glapi_table *_glapi_DispatchTSD = (struct _glapi_table *) __glapi #endif PUBLIC struct _glapi_table *_glapi_RealDispatch = (struct _glapi_table *) __glapi_noop_table; - /* Used when thread safety disabled */ PUBLIC void *_glapi_Context = NULL; +#endif /* defined(GLX_USE_TLS) */ + static GLboolean DispatchOverride = GL_FALSE; @@ -224,7 +275,7 @@ str_dup(const char *str) PUBLIC void _glapi_check_multithread(void) { -#if defined(THREADS) +#if defined(THREADS) && !defined(GLX_USE_TLS) if (!ThreadSafe) { static unsigned long knownID; static GLboolean firstCall = GL_TRUE; @@ -255,7 +306,9 @@ PUBLIC void _glapi_set_context(void *context) { (void) __unused_noop_functions; /* silence a warning */ -#if defined(THREADS) +#if defined(GLX_USE_TLS) + _glapi_tls_Context = context; +#elif defined(THREADS) (void) __unused_threadsafe_functions; /* silence a warning */ _glthread_SetTSD(&ContextTSD, context); _glapi_Context = (ThreadSafe) ? NULL : context; @@ -274,7 +327,9 @@ _glapi_set_context(void *context) PUBLIC void * _glapi_get_context(void) { -#if defined(THREADS) +#if defined(GLX_USE_TLS) + return _glapi_tls_Context; +#elif defined(THREADS) if (ThreadSafe) { return _glthread_GetTSD(&ContextTSD); } @@ -294,6 +349,13 @@ _glapi_get_context(void) PUBLIC void _glapi_set_dispatch(struct _glapi_table *dispatch) { +#if defined(PTHREADS) || defined(GLX_USE_TLS) + static pthread_once_t once_control = PTHREAD_ONCE_INIT; + + + pthread_once( & once_control, init_glapi_relocs ); +#endif + if (!dispatch) { /* use the no-op functions */ dispatch = (struct _glapi_table *) __glapi_noop_table; @@ -304,7 +366,15 @@ _glapi_set_dispatch(struct _glapi_table *dispatch) } #endif -#if defined(THREADS) +#if defined(GLX_USE_TLS) + if (DispatchOverride) { + _glapi_tls_RealDispatch = dispatch; + } + else { + _glthread_SetTSD(&_gl_DispatchTSD, (void *) dispatch); + _glapi_tls_Dispatch = dispatch; + } +#elif defined(THREADS) if (DispatchOverride) { _glthread_SetTSD(&RealDispatchTSD, (void *) dispatch); if (ThreadSafe) @@ -342,7 +412,13 @@ _glapi_set_dispatch(struct _glapi_table *dispatch) PUBLIC struct _glapi_table * _glapi_get_dispatch(void) { -#if defined(THREADS) +#if defined(GLX_USE_TLS) + struct _glapi_table * api = (DispatchOverride) + ? _glapi_tls_RealDispatch : _glapi_tls_Dispatch; + + assert( api != NULL ); + return api; +#elif defined(THREADS) if (ThreadSafe) { if (DispatchOverride) { return (struct _glapi_table *) _glthread_GetTSD(&RealDispatchTSD); @@ -399,7 +475,10 @@ _glapi_begin_dispatch_override(struct _glapi_table *override) _glapi_set_dispatch(real); -#if defined(THREADS) +#if defined(GLX_USE_TLS) + _glthread_SetTSD(&_gl_DispatchTSD, (void *) override); + _glapi_tls_Dispatch = override; +#elif defined(THREADS) _glthread_SetTSD(&_gl_DispatchTSD, (void *) override); if ( ThreadSafe ) { _glapi_Dispatch = (struct _glapi_table *) __glapi_threadsafe_table; @@ -424,10 +503,14 @@ _glapi_end_dispatch_override(int layer) DispatchOverride = GL_FALSE; _glapi_set_dispatch(real); /* the rest of this isn't needed, just play it safe */ -#if defined(THREADS) +#if defined(GLX_USE_TLS) + _glapi_tls_RealDispatch = NULL; +#else +# if defined(THREADS) _glthread_SetTSD(&RealDispatchTSD, NULL); -#endif +# endif _glapi_RealDispatch = NULL; +#endif } @@ -439,7 +522,9 @@ _glapi_get_override_dispatch(int layer) } else { if (DispatchOverride) { -#if defined(THREADS) +#if defined(GLX_USE_TLS) + return (struct _glapi_table *) _glapi_tls_Dispatch; +#elif defined(THREADS) return (struct _glapi_table *) _glthread_GetTSD(&_gl_DispatchTSD); #else return _glapi_Dispatch; @@ -498,9 +583,15 @@ get_static_proc_offset(const char *funcName) #ifdef USE_X86_ASM + +#if defined( GLX_USE_TLS ) +extern GLubyte gl_dispatch_functions_start[]; +extern GLubyte gl_dispatch_functions_end[]; +#else extern const GLubyte gl_dispatch_functions_start[]; +#endif -# if defined(THREADS) +# if defined(THREADS) && !defined(GLX_USE_TLS) # define X86_DISPATCH_FUNCTION_SIZE 32 # else # define X86_DISPATCH_FUNCTION_SIZE 16 @@ -603,45 +694,20 @@ static _glapi_proc generate_entrypoint(GLuint functionOffset) { #if defined(USE_X86_ASM) - /* - * This x86 code contributed by Josh Vanderhoof. - * - * 0: a1 10 32 54 76 movl __glapi_Dispatch,%eax - * 00 01 02 03 04 - * 5: 85 c0 testl %eax,%eax - * 05 06 - * 7: 74 06 je f - * 07 08 - * 9: ff a0 10 32 54 76 jmp *0x76543210(%eax) - * 09 0a 0b 0c 0d 0e - * f: e8 fc ff ff ff call __glapi_get_dispatch - * 0f 10 11 12 13 - * 14: ff a0 10 32 54 76 jmp *0x76543210(%eax) - * 14 15 16 17 18 19 + /* 32 is chosen as something of a magic offset. For x86, the dispatch + * at offset 32 is the first one where the offset in the + * "jmp OFFSET*4(%eax)" can't be encoded in a single byte. */ - static const unsigned char insn_template[] = { - 0xa1, 0x00, 0x00, 0x00, 0x00, - 0x85, 0xc0, - 0x74, 0x06, - 0xff, 0xa0, 0x00, 0x00, 0x00, 0x00, - 0xe8, 0x00, 0x00, 0x00, 0x00, - 0xff, 0xa0, 0x00, 0x00, 0x00, 0x00 - }; - unsigned char *code = (unsigned char *) malloc(sizeof(insn_template)); - unsigned int next_insn; - if (code) { - memcpy(code, insn_template, sizeof(insn_template)); + const GLubyte * const template_func = gl_dispatch_functions_start + + (X86_DISPATCH_FUNCTION_SIZE * 32); + GLubyte * const code = (GLubyte *) malloc( X86_DISPATCH_FUNCTION_SIZE ); -#if defined( THREADS ) - *(unsigned int *)(code + 0x01) = (unsigned int)&_glapi_DispatchTSD; -#else - *(unsigned int *)(code + 0x01) = (unsigned int)&_glapi_Dispatch; -#endif - *(unsigned int *)(code + 0x0b) = (unsigned int)functionOffset * 4; - next_insn = (unsigned int)(code + 0x14); - *(unsigned int *)(code + 0x10) = (unsigned int)_glapi_get_dispatch - next_insn; - *(unsigned int *)(code + 0x16) = (unsigned int)functionOffset * 4; + + if ( code != NULL ) { + (void) memcpy( code, template_func, X86_DISPATCH_FUNCTION_SIZE ); + fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset ); } + return (_glapi_proc) code; #elif defined(USE_SPARC_ASM) @@ -707,10 +773,19 @@ static void fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset) { #if defined(USE_X86_ASM) - - unsigned char *code = (unsigned char *) entrypoint; - *(unsigned int *)(code + 0x0b) = offset * 4; - *(unsigned int *)(code + 0x16) = offset * 4; + GLubyte * const code = (GLubyte *) entrypoint; + + +#if X86_DISPATCH_FUNCTION_SIZE == 32 + *((unsigned int *)(code + 11)) = 4 * offset; + *((unsigned int *)(code + 22)) = 4 * offset; +#elif X86_DISPATCH_FUNCTION_SIZE == 16 && defined( GLX_USE_TLS ) + *((unsigned int *)(code + 8)) = 4 * offset; +#elif X86_DISPATCH_FUNCTION_SIZE == 16 + *((unsigned int *)(code + 7)) = 4 * offset; +#else +# error Invalid X86_DISPATCH_FUNCTION_SIZE! +#endif #elif defined(USE_SPARC_ASM) @@ -1028,3 +1103,25 @@ _glapi_check_table(const struct _glapi_table *table) (void) table; #endif } + + +/** + * Perform platform-specific GL API entry-point fixups. + * + * + */ +static void +init_glapi_relocs( void ) +{ +#if defined( USE_X86_ASM ) && defined( GLX_USE_TLS ) + extern void * _x86_get_dispatch(void); + const GLubyte * const get_disp = (const GLubyte *) _x86_get_dispatch; + GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start; + + + while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) { + (void) memcpy( curr_func, get_disp, 6 ); + curr_func += X86_DISPATCH_FUNCTION_SIZE; + } +#endif /* defined( USE_X86_ASM ) && defined( GLX_USE_TLS ) */ +} -- cgit v1.2.3