On 06/26/2017 01:24 PM, Tom de Vries wrote:
Hi,
I've written a patch series to facilitate debugging libgomp openacc
testcase failures on the nvptx accelerator.
When running an openacc test-case on an nvptx accelerator, the
following happens:
- the plugin obtains the ptx assembly for the acceleration kernels
- it calls the cuda jit to compile and link the ptx into a module
- it loads the module
- it starts an acceleration kernel
The patch series adds these environment variables:
- GOMP_OPENACC_NVPTX_SAVE_TEMPS: a means to save the resulting module
such that it can be investigated using nvdisasm and cuobjdump.
- GOMP_OPENACC_NVPTX_DISASM: a means to see the resulting module in
the debug output, by writing it into a file and calling nvdisasm on
it
- GOMP_OPENACC_NVPTX_JIT: a means to set parameters of the
compilation/linking process, currently supporting:
* -O[0-4], mapping onto CU_JIT_OPTIMIZATION_LEVEL
* -ori, mapping onto CU_JIT_NEW_SM3X_OPT
The patch series consists of these patches:
1. Show value of GOMP_OPENACC_DIM in libgomp nvptx plugin
This patch adds a debug message (for GOMP_DEBUG=1) about the value of
the GOMP_OPENACC_DIM variable read from the environment.
Thanks,
- Tom
0001-Show-value-of-GOMP_OPENACC_DIM-in-libgomp-nvptx-plugin.patch
Show value of GOMP_OPENACC_DIM in libgomp nvptx plugin
2017-06-26 Tom de Vries <tom@codesourcery.com>
* plugin/plugin-nvptx.c (notify_var): New function.
(nvptx_exec): Use notify_var for GOMP_OPENACC_DIM.
---
libgomp/plugin/plugin-nvptx.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index 0e1b3e2..71630b5 100644
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -867,6 +867,14 @@ nvptx_get_num_devices (void)
return n;
}
+static void
+notify_var (const char *var_name, const char *env_var)
+{
+ if (env_var == NULL)
+ GOMP_PLUGIN_debug (0, "%s: <Not defined>\n", var_name);
+ else
+ GOMP_PLUGIN_debug (0, "%s: '%s'\n", var_name, env_var);
+}
static bool
link_ptx (CUmodule *module, const struct targ_ptx_obj *ptx_objs,
@@ -1089,10 +1097,12 @@ nvptx_exec (void (*fn), size_t mapnum, void **hostaddrs, void **devaddrs,
pthread_mutex_lock (&ptx_dev_lock);
if (!default_dims[0])
{
+ const char *var_name = "GOMP_OPENACC_DIM";
/* We only read the environment variable once. You can't
change it in the middle of execution. The syntax is
the same as for the -fopenacc-dim compilation option. */
- const char *env_var = getenv ("GOMP_OPENACC_DIM");
+ const char *env_var = getenv (var_name);
+ notify_var (var_name, env_var);
if (env_var)
{
const char *pos = env_var;