From fb67006eeca0c8e2bfdf86576ed3109dacaf6868 Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Wed, 30 Nov 2022 22:09:35 +0100 Subject: [PATCH] nvptx: Support global constructors/destructors via 'collect2' for offloading This extends "nvptx: Support global constructors/destructors via 'collect2'" for offloading. libgcc/ * config/nvptx/crtstuff.c ["mgomp"] (__do_global_ctors__entry__mgomp) (__do_global_dtors__entry__mgomp): New. [!"mgomp"] (__do_global_ctors__entry, __do_global_dtors__entry): New. libgomp/ * plugin/plugin-nvptx.c (nvptx_do_global_cdtors): New. (nvptx_close_device, GOMP_OFFLOAD_load_image) (GOMP_OFFLOAD_unload_image): Call it. --- libgcc/config/nvptx/crtstuff.c | 64 ++++++++++++++++++- libgomp/plugin/plugin-nvptx.c | 113 ++++++++++++++++++++++++++++++++- 2 files changed, 175 insertions(+), 2 deletions(-) diff --git a/libgcc/config/nvptx/crtstuff.c b/libgcc/config/nvptx/crtstuff.c index 0823fc49901..8dc80687e0a 100644 --- a/libgcc/config/nvptx/crtstuff.c +++ b/libgcc/config/nvptx/crtstuff.c @@ -29,6 +29,14 @@ files (via 'CRT_BEGIN' and 'CRT_END'): 'crtbegin.o' and 'crtend.o', but we do so anyway, for symmetry with other configurations. */ + +/* See 'crt0.c', 'mgomp.c'. */ +#if defined(__nvptx_softstack__) && defined(__nvptx_unisimt__) +extern void *__nvptx_stacks[32] __attribute__((shared,nocommon)); +extern unsigned __nvptx_uni[32] __attribute__((shared,nocommon)); +#endif + + #ifdef CRT_BEGIN void @@ -37,6 +45,33 @@ __do_global_ctors (void) DO_GLOBAL_CTORS_BODY; } +/* Need '.entry' wrapper for offloading. */ + +# if defined(__nvptx_softstack__) && defined(__nvptx_unisimt__) + +__attribute__((kernel)) void __do_global_ctors__entry__mgomp (void *); + +void +__do_global_ctors__entry__mgomp (void *nvptx_stacks_0) +{ + __nvptx_stacks[0] = nvptx_stacks_0; + __nvptx_uni[0] = 0; + + __do_global_ctors (); +} + +# else + +__attribute__((kernel)) void __do_global_ctors__entry (void); + +void +__do_global_ctors__entry (void) +{ + __do_global_ctors (); +} + +# endif + #elif defined(CRT_END) /* ! CRT_BEGIN */ void @@ -45,7 +80,7 @@ __do_global_dtors (void) /* In this configuration here, there's no way that "this routine is run more than once [...] when exit is called recursively": for nvptx target, the call to '__do_global_dtors' is registered via 'atexit', which doesn't - re-enter a function already run. + re-enter a function already run, and neither does nvptx offload target. Therefore, we do *not* "arrange to remember where in the list we left off processing". */ func_ptr *p; @@ -53,6 +88,33 @@ __do_global_dtors (void) (*p++) (); } +/* Need '.entry' wrapper for offloading. */ + +# if defined(__nvptx_softstack__) && defined(__nvptx_unisimt__) + +__attribute__((kernel)) void __do_global_dtors__entry__mgomp (void *); + +void +__do_global_dtors__entry__mgomp (void *nvptx_stacks_0) +{ + __nvptx_stacks[0] = nvptx_stacks_0; + __nvptx_uni[0] = 0; + + __do_global_dtors (); +} + +# else + +__attribute__((kernel)) void __do_global_dtors__entry (void); + +void +__do_global_dtors__entry (void) +{ + __do_global_dtors (); +} + +# endif + #else /* ! CRT_BEGIN && ! CRT_END */ #error "One of CRT_BEGIN or CRT_END must be defined." #endif diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c index fcc97c6e0d5..395639537e8 100644 --- a/libgomp/plugin/plugin-nvptx.c +++ b/libgomp/plugin/plugin-nvptx.c @@ -338,6 +338,11 @@ struct ptx_device static struct ptx_device **ptx_devices; +static bool nvptx_do_global_cdtors (CUmodule, struct ptx_device *, + const char *); +static size_t nvptx_stacks_size (); +static void *nvptx_stacks_acquire (struct ptx_device *, size_t, int); + static inline struct nvptx_thread * nvptx_thread (void) { @@ -557,6 +562,17 @@ nvptx_close_device (struct ptx_device *ptx_dev) if (!ptx_dev) return true; + bool ret = true; + + for (struct ptx_image_data *image = ptx_dev->images; + image != NULL; + image = image->next) + { + if (!nvptx_do_global_cdtors (image->module, ptx_dev, + "__do_global_dtors__entry")) + ret = false; + } + for (struct ptx_free_block *b = ptx_dev->free_blocks; b;) { struct ptx_free_block *b_next = b->next; @@ -577,7 +593,8 @@ nvptx_close_device (struct ptx_device *ptx_dev) CUDA_CALL (cuCtxDestroy, ptx_dev->ctx); free (ptx_dev); - return true; + + return ret; } static int @@ -1280,6 +1297,93 @@ nvptx_set_clocktick (CUmodule module, struct ptx_device *dev) GOMP_PLUGIN_fatal ("cuMemcpyHtoD error: %s", cuda_error (r)); } +/* Invoke MODULE's global constructors/destructors. */ + +static bool +nvptx_do_global_cdtors (CUmodule module, struct ptx_device *ptx_dev, + const char *funcname) +{ + bool ret = true; + char *funcname_mgomp = NULL; + CUresult r; + CUfunction funcptr; + r = CUDA_CALL_NOCHECK (cuModuleGetFunction, + &funcptr, module, funcname); + GOMP_PLUGIN_debug (0, "cuModuleGetFunction (%s): %s\n", + funcname, cuda_error (r)); + if (r == CUDA_ERROR_NOT_FOUND) + { + /* Try '[funcname]__mgomp'. */ + + size_t funcname_len = strlen (funcname); + const char *mgomp_suffix = "__mgomp"; + size_t mgomp_suffix_len = strlen (mgomp_suffix); + funcname_mgomp + = GOMP_PLUGIN_malloc (funcname_len + mgomp_suffix_len + 1); + memcpy (funcname_mgomp, funcname, funcname_len); + memcpy (funcname_mgomp + funcname_len, + mgomp_suffix, mgomp_suffix_len + 1); + funcname = funcname_mgomp; + + r = CUDA_CALL_NOCHECK (cuModuleGetFunction, + &funcptr, module, funcname); + GOMP_PLUGIN_debug (0, "cuModuleGetFunction (%s): %s\n", + funcname, cuda_error (r)); + } + if (r == CUDA_ERROR_NOT_FOUND) + ; + else if (r != CUDA_SUCCESS) + { + GOMP_PLUGIN_error ("cuModuleGetFunction (%s) error: %s", + funcname, cuda_error (r)); + ret = false; + } + else + { + /* If necessary, set up soft stack. */ + void *nvptx_stacks_0; + void *kargs[1]; + if (funcname_mgomp) + { + size_t stack_size = nvptx_stacks_size (); + pthread_mutex_lock (&ptx_dev->omp_stacks.lock); + nvptx_stacks_0 = nvptx_stacks_acquire (ptx_dev, stack_size, 1); + nvptx_stacks_0 += stack_size; + kargs[0] = &nvptx_stacks_0; + } + r = CUDA_CALL_NOCHECK (cuLaunchKernel, + funcptr, + 1, 1, 1, 1, 1, 1, + /* sharedMemBytes */ 0, + /* hStream */ NULL, + /* kernelParams */ funcname_mgomp ? kargs : NULL, + /* extra */ NULL); + if (r != CUDA_SUCCESS) + { + GOMP_PLUGIN_error ("cuLaunchKernel (%s) error: %s", + funcname, cuda_error (r)); + ret = false; + } + + r = CUDA_CALL_NOCHECK (cuStreamSynchronize, + NULL); + if (r != CUDA_SUCCESS) + { + GOMP_PLUGIN_error ("cuStreamSynchronize (%s) error: %s", + funcname, cuda_error (r)); + ret = false; + } + + if (funcname_mgomp) + pthread_mutex_unlock (&ptx_dev->omp_stacks.lock); + } + + if (funcname_mgomp) + free (funcname_mgomp); + + return ret; +} + /* Load the (partial) program described by TARGET_DATA to device number ORD. Allocate and return TARGET_TABLE. If not NULL, REV_FN_TABLE will contain the on-device addresses of the functions for reverse offload. @@ -1452,6 +1556,9 @@ GOMP_OFFLOAD_load_image (int ord, unsigned version, const void *target_data, nvptx_set_clocktick (module, dev); + if (!nvptx_do_global_cdtors (module, dev, "__do_global_ctors__entry")) + return -1; + return fn_entries + var_entries + other_entries; } @@ -1477,6 +1584,10 @@ GOMP_OFFLOAD_unload_image (int ord, unsigned version, const void *target_data) for (prev_p = &dev->images; (image = *prev_p) != 0; prev_p = &image->next) if (image->target_data == target_data) { + if (!nvptx_do_global_cdtors (image->module, dev, + "__do_global_dtors__entry")) + ret = false; + *prev_p = image->next; if (CUDA_CALL_NOCHECK (cuModuleUnload, image->module) != CUDA_SUCCESS) ret = false; -- 2.25.1