public inbox for gcc-cvs@sourceware.org
help / color / mirror / Atom feed
* [gcc/devel/omp/gcc-12] openmp, nvptx: low-lat memory access traits
@ 2022-06-29 14:45 Kwok Yeung
  0 siblings, 0 replies; only message in thread
From: Kwok Yeung @ 2022-06-29 14:45 UTC (permalink / raw)
  To: gcc-cvs

https://gcc.gnu.org/g:f6c61b324c670c50f2bda3753aadf8d1a8eea962

commit f6c61b324c670c50f2bda3753aadf8d1a8eea962
Author: Andrew Stubbs <ams@codesourcery.com>
Date:   Fri Mar 11 14:33:11 2022 +0000

    openmp, nvptx: low-lat memory access traits
    
    The NVPTX low latency memory is not accessible outside the team that allocates
    it, and therefore should be unavailable for allocators with the access trait
    "all".  This change means that the omp_low_lat_mem_alloc predefined
    allocator now implicitly implies the "pteam" trait.
    
            Backport of a patch posted at
            https://gcc.gnu.org/pipermail/gcc-patches/2022-January/589355.html
    
    libgomp/ChangeLog:
    
            * allocator.c (MEMSPACE_VALIDATE): New macro.
            (omp_aligned_alloc): Use MEMSPACE_VALIDATE.
            (omp_aligned_calloc): Likewise.
            (omp_realloc): Likewise.
            * config/nvptx/allocator.c (nvptx_memspace_validate): New function.
            (MEMSPACE_VALIDATE): New macro.
            * testsuite/libgomp.c/allocators-4.c (main): Add access trait.
            * testsuite/libgomp.c/allocators-6.c (main): Add access trait.
            * testsuite/libgomp.c/allocators-7.c: New test.

Diff:
---
 libgomp/ChangeLog.omp                      | 15 +++++++
 libgomp/allocator.c                        | 15 +++++++
 libgomp/config/nvptx/allocator.c           | 11 +++++
 libgomp/testsuite/libgomp.c/allocators-4.c |  7 +--
 libgomp/testsuite/libgomp.c/allocators-6.c |  7 +--
 libgomp/testsuite/libgomp.c/allocators-7.c | 68 ++++++++++++++++++++++++++++++
 6 files changed, 117 insertions(+), 6 deletions(-)

diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index 50773dc4f67..c0626439b0d 100644
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,18 @@
+2022-03-11  Andrew Stubbs <ams@codesourcery.com>
+
+	Backport of a patch posted at
+	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/589355.html
+
+	* allocator.c (MEMSPACE_VALIDATE): New macro.
+	(omp_aligned_alloc): Use MEMSPACE_VALIDATE.
+	(omp_aligned_calloc): Likewise.
+	(omp_realloc): Likewise.
+	* config/nvptx/allocator.c (nvptx_memspace_validate): New function.
+	(MEMSPACE_VALIDATE): New macro.
+	* testsuite/libgomp.c/allocators-4.c (main): Add access trait.
+	* testsuite/libgomp.c/allocators-6.c (main): Add access trait.
+	* testsuite/libgomp.c/allocators-7.c: New test.
+
 2022-03-11  Andrew Stubbs <ams@codesourcery.com>
 
 	Backport of a patch posted at
diff --git a/libgomp/allocator.c b/libgomp/allocator.c
index 724ecf3703c..7052052ad96 100644
--- a/libgomp/allocator.c
+++ b/libgomp/allocator.c
@@ -51,6 +51,9 @@
 #define MEMSPACE_FREE(MEMSPACE, ADDR, SIZE, PIN) \
   (PIN ? NULL : free (ADDR))
 #endif
+#ifndef MEMSPACE_VALIDATE
+#define MEMSPACE_VALIDATE(MEMSPACE, ACCESS) 1
+#endif
 
 /* Map the predefined allocators to the correct memory space.
    The index to this table is the omp_allocator_handle_t enum value.  */
@@ -279,6 +282,10 @@ retry:
   if (__builtin_add_overflow (size, new_size, &new_size))
     goto fail;
 
+  if (allocator_data
+      && !MEMSPACE_VALIDATE (allocator_data->memspace, allocator_data->access))
+    goto fail;
+
   if (__builtin_expect (allocator_data
 			&& allocator_data->pool_size < ~(uintptr_t) 0, 0))
     {
@@ -505,6 +512,10 @@ retry:
   if (__builtin_add_overflow (size_temp, new_size, &new_size))
     goto fail;
 
+  if (allocator_data
+      && !MEMSPACE_VALIDATE (allocator_data->memspace, allocator_data->access))
+    goto fail;
+
   if (__builtin_expect (allocator_data
 			&& allocator_data->pool_size < ~(uintptr_t) 0, 0))
     {
@@ -675,6 +686,10 @@ retry:
     goto fail;
   old_size = data->size;
 
+  if (allocator_data
+      && !MEMSPACE_VALIDATE (allocator_data->memspace, allocator_data->access))
+    goto fail;
+
   if (__builtin_expect (allocator_data
 			&& allocator_data->pool_size < ~(uintptr_t) 0, 0))
     {
diff --git a/libgomp/config/nvptx/allocator.c b/libgomp/config/nvptx/allocator.c
index f740b97f6ac..0102680b717 100644
--- a/libgomp/config/nvptx/allocator.c
+++ b/libgomp/config/nvptx/allocator.c
@@ -358,6 +358,15 @@ nvptx_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
     return realloc (addr, size);
 }
 
+static inline int
+nvptx_memspace_validate (omp_memspace_handle_t memspace, unsigned access)
+{
+  /* Disallow use of low-latency memory when it must be accessible by
+     all threads.  */
+  return (memspace != omp_low_lat_mem_space
+	  || access != omp_atv_all);
+}
+
 #define MEMSPACE_ALLOC(MEMSPACE, SIZE, PIN) \
   nvptx_memspace_alloc (MEMSPACE, SIZE)
 #define MEMSPACE_CALLOC(MEMSPACE, SIZE, PIN) \
@@ -366,5 +375,7 @@ nvptx_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
   nvptx_memspace_realloc (MEMSPACE, ADDR, OLDSIZE, SIZE)
 #define MEMSPACE_FREE(MEMSPACE, ADDR, SIZE, PIN) \
   nvptx_memspace_free (MEMSPACE, ADDR, SIZE)
+#define MEMSPACE_VALIDATE(MEMSPACE, ACCESS) \
+  nvptx_memspace_validate (MEMSPACE, ACCESS)
 
 #include "../../allocator.c"
diff --git a/libgomp/testsuite/libgomp.c/allocators-4.c b/libgomp/testsuite/libgomp.c/allocators-4.c
index 9fa6aa1624f..83a60933c21 100644
--- a/libgomp/testsuite/libgomp.c/allocators-4.c
+++ b/libgomp/testsuite/libgomp.c/allocators-4.c
@@ -23,10 +23,11 @@ main ()
   #pragma omp target
   {
     /* Ensure that the memory we get *is* low-latency with a null-fallback.  */
-    omp_alloctrait_t traits[1]
-      = { { omp_atk_fallback, omp_atv_null_fb } };
+    omp_alloctrait_t traits[2]
+      = { { omp_atk_fallback, omp_atv_null_fb },
+	  { omp_atk_access, omp_atv_pteam } };
     omp_allocator_handle_t lowlat = omp_init_allocator (omp_low_lat_mem_space,
-							1, traits);
+							2, traits);
 
     int size = 4;
 
diff --git a/libgomp/testsuite/libgomp.c/allocators-6.c b/libgomp/testsuite/libgomp.c/allocators-6.c
index 90bf73095ef..9c22466fbd6 100644
--- a/libgomp/testsuite/libgomp.c/allocators-6.c
+++ b/libgomp/testsuite/libgomp.c/allocators-6.c
@@ -23,10 +23,11 @@ main ()
   #pragma omp target
   {
     /* Ensure that the memory we get *is* low-latency with a null-fallback.  */
-    omp_alloctrait_t traits[1]
-      = { { omp_atk_fallback, omp_atv_null_fb } };
+    omp_alloctrait_t traits[2]
+      = { { omp_atk_fallback, omp_atv_null_fb },
+	  { omp_atk_access, omp_atv_pteam } };
     omp_allocator_handle_t lowlat = omp_init_allocator (omp_low_lat_mem_space,
-							1, traits);
+							2, traits);
 
     int size = 16;
 
diff --git a/libgomp/testsuite/libgomp.c/allocators-7.c b/libgomp/testsuite/libgomp.c/allocators-7.c
new file mode 100644
index 00000000000..a0a738b1d1d
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/allocators-7.c
@@ -0,0 +1,68 @@
+/* { dg-do run } */
+
+/* { dg-require-effective-target offload_device } */
+/* { dg-xfail-if "not implemented" { ! offload_target_nvptx } } */
+
+/* Test that GPU low-latency allocation is limited to team access.  */
+
+#include <stddef.h>
+#include <omp.h>
+
+#pragma omp requires dynamic_allocators
+
+int
+main ()
+{
+  #pragma omp target
+  {
+    /* Ensure that the memory we get *is* low-latency with a null-fallback.  */
+    omp_alloctrait_t traits[2]
+      = { { omp_atk_fallback, omp_atv_null_fb },
+	  { omp_atk_access, omp_atv_pteam } };
+    omp_allocator_handle_t lowlat = omp_init_allocator (omp_low_lat_mem_space,
+							2, traits);
+
+    omp_alloctrait_t traits_all[2]
+      = { { omp_atk_fallback, omp_atv_null_fb },
+	  { omp_atk_access, omp_atv_all } };
+    omp_allocator_handle_t lowlat_all
+      = omp_init_allocator (omp_low_lat_mem_space, 2, traits_all);
+
+    omp_alloctrait_t traits_default[1]
+      = { { omp_atk_fallback, omp_atv_null_fb } };
+    omp_allocator_handle_t lowlat_default
+      = omp_init_allocator (omp_low_lat_mem_space, 1, traits_default);
+
+    void *a = omp_alloc(1, lowlat);	    // good
+    void *b = omp_alloc(1, lowlat_all);     // bad
+    void *c = omp_alloc(1, lowlat_default); // bad
+
+    if (!a || b || c)
+      __builtin_abort ();
+
+    omp_free (a, lowlat);
+
+
+    a = omp_calloc(1, 1, lowlat);	  // good
+    b = omp_calloc(1, 1, lowlat_all);     // bad
+    c = omp_calloc(1, 1, lowlat_default); // bad
+
+    if (!a || b || c)
+      __builtin_abort ();
+
+    omp_free (a, lowlat);
+
+
+    a = omp_realloc(NULL, 1, lowlat, lowlat);		      // good
+    b = omp_realloc(NULL, 1, lowlat_all, lowlat_all);	      // bad
+    c = omp_realloc(NULL, 1, lowlat_default, lowlat_default); // bad
+
+    if (!a || b || c)
+      __builtin_abort ();
+
+    omp_free (a, lowlat);
+  }
+
+return 0;
+}
+


^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2022-06-29 14:45 UTC | newest]

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-06-29 14:45 [gcc/devel/omp/gcc-12] openmp, nvptx: low-lat memory access traits Kwok Yeung

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).