Handle GOMP_OPENACC_NVPTX_{DISASM,SAVE_TEMPS} in libgomp nvptx plugin
2017-06-26 Tom de Vries <tom@codesourcery.com>
* plugin/plugin-nvptx.c (do_prog, debug_linkout): New function.
(link_ptx): Use debug_linkout.
---
libgomp/plugin/plugin-nvptx.c | 105 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 105 insertions(+)
@@ -47,6 +47,9 @@
#include <unistd.h>
#include <assert.h>
#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
#if PLUGIN_NVPTX_DYNAMIC
# include <dlfcn.h>
@@ -138,6 +141,8 @@ init_cuda_lib (void)
# define init_cuda_lib() true
#endif
+#include "secure_getenv.h"
+
/* Convenience macros for the frequently used CUDA library call and
error handling sequence as well as CUDA library calls that
do the error checking themselves or don't do it at all. */
@@ -876,6 +881,104 @@ notify_var (const char *var_name, const char *env_var)
GOMP_PLUGIN_debug (0, "%s: '%s'\n", var_name, env_var);
}
+static void
+do_prog (const char *prog, const char *arg)
+{
+ pid_t pid = fork ();
+
+ if (pid == -1)
+ {
+ GOMP_PLUGIN_error ("Fork failed");
+ return;
+ }
+ else if (pid > 0)
+ {
+ int status;
+ waitpid (pid, &status, 0);
+ if (!WIFEXITED (status))
+ GOMP_PLUGIN_error ("Running %s %s failed", prog, arg);
+ }
+ else
+ {
+ execlp (prog, prog /* argv[0] */, arg, NULL);
+ abort ();
+ }
+}
+
+static void
+debug_linkout (void *linkout, size_t linkoutsize)
+{
+ static int gomp_openacc_nvptx_disasm = -1;
+ if (gomp_openacc_nvptx_disasm == -1)
+ {
+ const char *var_name = "GOMP_OPENACC_NVPTX_DISASM";
+ const char *env_var = secure_getenv (var_name);
+ notify_var (var_name, env_var);
+ gomp_openacc_nvptx_disasm
+ = ((env_var != NULL && env_var[0] == '1' && env_var[1] == '\0')
+ ? 1 : 0);
+ }
+
+ static int gomp_openacc_nvptx_save_temps = -1;
+ if (gomp_openacc_nvptx_save_temps == -1)
+ {
+ const char *var_name = "GOMP_OPENACC_NVPTX_SAVE_TEMPS";
+ const char *env_var = secure_getenv (var_name);
+ notify_var (var_name, env_var);
+ gomp_openacc_nvptx_save_temps
+ = ((env_var != NULL && env_var[0] == '1' && env_var[1] == '\0')
+ ? 1 : 0);
+ }
+
+ if (gomp_openacc_nvptx_disasm == 0
+ && gomp_openacc_nvptx_save_temps == 0)
+ return;
+
+ const char *prefix = "plugin-nvptx.";
+ const char *postfix = ".cubin";
+ const int len = (strlen (prefix)
+ + 20 /* %lld. */
+ + strlen (postfix)
+ + 1 /* '\0'. */);
+ char file_name[len];
+ int res = snprintf (file_name, len, "%s%lld%s", prefix,
+ (long long)getpid (), postfix);
+ assert (res < len); /* Assert there's no truncation. */
+
+ GOMP_PLUGIN_debug (0, "Generating %s with size %zu\n",
+ file_name, linkoutsize);
+ FILE *cubin_file = fopen (file_name, "wb");
+ if (cubin_file == NULL)
+ {
+ GOMP_PLUGIN_debug (0, "Opening %s failed\n", file_name);
+ return;
+ }
+
+ fwrite (linkout, linkoutsize, 1, cubin_file);
+ unsigned int write_succeeded = ferror (cubin_file) == 0;
+ if (!write_succeeded)
+ GOMP_PLUGIN_debug (0, "Writing %s failed\n", file_name);
+
+ res = fclose (cubin_file);
+ if (res != 0)
+ GOMP_PLUGIN_debug (0, "Closing %s failed\n", file_name);
+
+ if (!write_succeeded)
+ return;
+
+ if (gomp_openacc_nvptx_disasm == 1)
+ {
+ GOMP_PLUGIN_debug (0, "Disassembling %s\n", file_name);
+ do_prog ("nvdisasm", file_name);
+ }
+
+ if (gomp_openacc_nvptx_save_temps == 0)
+ {
+ GOMP_PLUGIN_debug (0, "Removing %s\n", file_name);
+ remove (file_name);
+ }
+}
+
static bool
link_ptx (CUmodule *module, const struct targ_ptx_obj *ptx_objs,
unsigned num_objs)
@@ -939,6 +1042,8 @@ link_ptx (CUmodule *module, const struct targ_ptx_obj *ptx_objs,
return false;
}
+ debug_linkout (linkout, linkoutsize);
+
CUDA_CALL (cuModuleLoadData, module, linkout);
CUDA_CALL (cuLinkDestroy, linkstate);
return true;