libgomp, openmp: Add ompx_pinned_mem_alloc

This creates a new predefined allocator as a shortcut for using pinned
memory with OpenMP.  The name uses the OpenMP extension space and is
intended to be consistent with other OpenMP implementations currently in
development.

The allocator is equivalent to using a custom allocator with the pinned
trait and the null fallback trait.

	Backport of a patch posted at
	https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588951.html

	* allocator.c (omp_max_predefined_alloc): Update.
	(omp_aligned_alloc): Support ompx_pinned_mem_alloc.
	(omp_free): Likewise.
	(omp_aligned_calloc): Likewise.
	(omp_realloc): Likewise.
	* omp.h.in (omp_allocator_handle_t): Add ompx_pinned_mem_alloc.
	* omp_lib.f90.in: Add ompx_pinned_mem_alloc.
	* testsuite/libgomp.c/alloc-pinned-5.c: New test.
	* testsuite/libgomp.c/alloc-pinned-6.c: New test.
	* testsuite/libgomp.fortran/alloc-pinned-1.f90: New test.

diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index 1b03dfd39eb5cd3f40f8611646230706c5bd1976..50773dc4f672e9297eb0a62830308c0461d6f120 100644 (file)
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,19 @@
+2022-03-11  Andrew Stubbs <ams@codesourcery.com>
+
+       Backport of a patch posted at
+       https://gcc.gnu.org/pipermail/gcc-patches/2022-January/588951.html
+
+       * allocator.c (omp_max_predefined_alloc): Update.
+       (omp_aligned_alloc): Support ompx_pinned_mem_alloc.
+       (omp_free): Likewise.
+       (omp_aligned_calloc): Likewise.
+       (omp_realloc): Likewise.
+       * omp.h.in (omp_allocator_handle_t): Add ompx_pinned_mem_alloc.
+       * omp_lib.f90.in: Add ompx_pinned_mem_alloc.
+       * testsuite/libgomp.c/alloc-pinned-5.c: New test.
+       * testsuite/libgomp.c/alloc-pinned-6.c: New test.
+       * testsuite/libgomp.fortran/alloc-pinned-1.f90: New test.
+
 2022-03-10  Andrew Stubbs <ams@codesourcery.com>
 
        Backport of a patch posted at

diff --git a/libgomp/allocator.c b/libgomp/allocator.c
index a1862f890948bea58297e28b4faa98fad33721bd..724ecf3703c4459a9ef7fc3f398f23c31cb65d79 100644 (file)
--- a/libgomp/allocator.c
+++ b/libgomp/allocator.c
@@ -32,7 +32,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define omp_max_predefined_alloc omp_thread_mem_alloc
+#define omp_max_predefined_alloc ompx_pinned_mem_alloc
 
 /* These macros may be overridden in config/<target>/allocator.c.  */
 #ifndef MEMSPACE_ALLOC
@@ -64,6 +64,7 @@ static const omp_memspace_handle_t predefined_alloc_mapping[] = {
   omp_low_lat_mem_space,   /* omp_cgroup_mem_alloc. */
   omp_low_lat_mem_space,   /* omp_pteam_mem_alloc. */
   omp_low_lat_mem_space,   /* omp_thread_mem_alloc. */
+  omp_default_mem_space,   /* ompx_pinned_mem_alloc. */
 };
 
 struct omp_allocator_data
@@ -330,11 +331,15 @@ retry:
     }
   else
     {
-      omp_memspace_handle_t memspace = (allocator_data
-                                       ? allocator_data->memspace
-                                       : predefined_alloc_mapping[allocator]);
-      ptr = MEMSPACE_ALLOC (memspace, new_size,
-                           allocator_data && allocator_data->pinned);
+      omp_memspace_handle_t memspace __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->memspace
+          : predefined_alloc_mapping[allocator]);
+      int pinned __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->pinned
+          : allocator == ompx_pinned_mem_alloc);
+      ptr = MEMSPACE_ALLOC (memspace, new_size, pinned);
       if (ptr == NULL)
        goto fail;
     }
@@ -354,7 +359,8 @@ retry:
 fail:
   int fallback = (allocator_data
                  ? allocator_data->fallback
-                 : allocator == omp_default_mem_alloc
+                 : (allocator == omp_default_mem_alloc
+                    || allocator == ompx_pinned_mem_alloc)
                  ? omp_atv_null_fb
                  : omp_atv_default_mem_fb);
   switch (fallback)
@@ -413,7 +419,8 @@ void
 omp_free (void *ptr, omp_allocator_handle_t allocator)
 {
   struct omp_mem_header *data;
-  omp_memspace_handle_t memspace = omp_default_mem_space;
+  omp_memspace_handle_t memspace __attribute__((unused))
+    = omp_default_mem_space;
   int pinned __attribute__((unused)) = false;
 
   if (ptr == NULL)
@@ -440,7 +447,10 @@ omp_free (void *ptr, omp_allocator_handle_t allocator)
       pinned = allocator_data->pinned;
     }
   else
-    memspace = predefined_alloc_mapping[data->allocator];
+    {
+      memspace = predefined_alloc_mapping[data->allocator];
+      pinned = (data->allocator == ompx_pinned_mem_alloc);
+    }
 
   MEMSPACE_FREE (memspace, data->ptr, data->size, pinned);
 }
@@ -530,8 +540,11 @@ retry:
       allocator_data->used_pool_size = used_pool_size;
       gomp_mutex_unlock (&allocator_data->lock);
 #endif
-      ptr = MEMSPACE_CALLOC (allocator_data->memspace, new_size,
-                            allocator_data->pinned);
+      int pinned __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->pinned
+          : allocator == ompx_pinned_mem_alloc);
+      ptr = MEMSPACE_CALLOC (allocator_data->memspace, new_size, pinned);
       if (ptr == NULL)
        {
 #ifdef HAVE_SYNC_BUILTINS
@@ -547,11 +560,15 @@ retry:
     }
   else
     {
-      omp_memspace_handle_t memspace = (allocator_data
-                                       ? allocator_data->memspace
-                                       : predefined_alloc_mapping[allocator]);
-      ptr = MEMSPACE_ALLOC (memspace, new_size,
-                           allocator_data && allocator_data->pinned);
+      omp_memspace_handle_t memspace __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->memspace
+          : predefined_alloc_mapping[allocator]);
+      int pinned __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->pinned
+          : allocator == ompx_pinned_mem_alloc);
+      ptr = MEMSPACE_CALLOC (memspace, new_size, pinned);
       if (ptr == NULL)
        goto fail;
     }
@@ -571,7 +588,8 @@ retry:
 fail:
   int fallback = (allocator_data
                  ? allocator_data->fallback
-                 : allocator == omp_default_mem_alloc
+                 : (allocator == omp_default_mem_alloc
+                    || allocator == ompx_pinned_mem_alloc)
                  ? omp_atv_null_fb
                  : omp_atv_default_mem_fb);
   switch (fallback)
@@ -716,11 +734,15 @@ retry:
       gomp_mutex_unlock (&allocator_data->lock);
 #endif
       if (prev_size)
-       new_ptr = MEMSPACE_REALLOC (allocator_data->memspace, data->ptr,
-                                   data->size, new_size,
-                                   (free_allocator_data
-                                    && free_allocator_data->pinned),
-                                   allocator_data->pinned);
+       {
+         int was_pinned __attribute__((unused))
+           = (free_allocator_data
+              ? free_allocator_data->pinned
+              : free_allocator == ompx_pinned_mem_alloc);
+         new_ptr = MEMSPACE_REALLOC (allocator_data->memspace, data->ptr,
+                                     data->size, new_size, was_pinned,
+                                     allocator_data->pinned);
+       }
       else
        new_ptr = MEMSPACE_ALLOC (allocator_data->memspace, new_size,
                                  allocator_data->pinned);
@@ -751,13 +773,20 @@ retry:
           && (free_allocator_data == NULL
               || free_allocator_data->pool_size == ~(uintptr_t) 0))
     {
-      omp_memspace_handle_t memspace = (allocator_data
-                                       ? allocator_data->memspace
-                                       : predefined_alloc_mapping[allocator]);
+      omp_memspace_handle_t memspace __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->memspace
+          : predefined_alloc_mapping[allocator]);
+      int was_pinned __attribute__((unused))
+       = (free_allocator_data
+          ? free_allocator_data->pinned
+          : free_allocator == ompx_pinned_mem_alloc);
+      int pinned __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->pinned
+          : allocator == ompx_pinned_mem_alloc);
       new_ptr = MEMSPACE_REALLOC (memspace, data->ptr, data->size, new_size,
-                                 (free_allocator_data
-                                  && free_allocator_data->pinned),
-                                 allocator_data && allocator_data->pinned);
+                                 was_pinned, pinned);
       if (new_ptr == NULL)
        goto fail;
       ret = (char *) new_ptr + sizeof (struct omp_mem_header);
@@ -768,12 +797,15 @@ retry:
     }
   else
     {
-      omp_memspace_handle_t memspace
+      omp_memspace_handle_t memspace __attribute__((unused))
        = (allocator_data
           ? allocator_data->memspace
           : predefined_alloc_mapping[allocator]);
-      new_ptr = MEMSPACE_ALLOC (memspace, new_size,
-                               allocator_data && allocator_data->pinned);
+      int pinned __attribute__((unused))
+       = (allocator_data
+          ? allocator_data->pinned
+          : allocator == ompx_pinned_mem_alloc);
+      new_ptr = MEMSPACE_ALLOC (memspace, new_size, pinned);
       if (new_ptr == NULL)
        goto fail;
     }
@@ -809,7 +841,8 @@ retry:
 fail:
   int fallback = (allocator_data
                  ? allocator_data->fallback
-                 : allocator == omp_default_mem_alloc
+                 : (allocator == omp_default_mem_alloc
+                    || allocator == ompx_pinned_mem_alloc)
                  ? omp_atv_null_fb
                  : omp_atv_default_mem_fb);
   switch (fallback)

diff --git a/libgomp/omp.h.in b/libgomp/omp.h.in
index 89c5d65bcd545cf1d6539969cb873fb8d8bc34d3..1d002d36aaef39c9a896448f7e2f0f120a932b2d 100644 (file)
--- a/libgomp/omp.h.in
+++ b/libgomp/omp.h.in
@@ -134,6 +134,7 @@ typedef enum omp_allocator_handle_t __GOMP_UINTPTR_T_ENUM
   omp_cgroup_mem_alloc = 6,
   omp_pteam_mem_alloc = 7,
   omp_thread_mem_alloc = 8,
+  ompx_pinned_mem_alloc = 9,
   __omp_allocator_handle_t_max__ = __UINTPTR_MAX__
 } omp_allocator_handle_t;
 

diff --git a/libgomp/omp_lib.f90.in b/libgomp/omp_lib.f90.in
index daf40dc8e6d71bbdd28ad7f1d5eac29457fb27d8..a095dad8962781cdf938ca459a52bb8445d005e3 100644 (file)
--- a/libgomp/omp_lib.f90.in
+++ b/libgomp/omp_lib.f90.in
@@ -158,6 +158,8 @@
                  parameter :: omp_pteam_mem_alloc = 7
         integer (kind=omp_allocator_handle_kind), &
                  parameter :: omp_thread_mem_alloc = 8
+        integer (kind=omp_allocator_handle_kind), &
+                 parameter :: ompx_pinned_mem_alloc = 9
         integer (omp_memspace_handle_kind), &
                  parameter :: omp_default_mem_space = 0
         integer (omp_memspace_handle_kind), &

diff --git a/libgomp/testsuite/libgomp.c/alloc-pinned-5.c b/libgomp/testsuite/libgomp.c/alloc-pinned-5.c
new file mode 100644 (file)
index 0000000..8355ca8
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-pinned-5.c
@@ -0,0 +1,76 @@
+/* { dg-do run } */
+
+/* { dg-xfail-run-if "Pinning not implemented on this host" { ! *-*-linux-gnu } } */
+
+/* Test that ompx_pinned_mem_alloc works.  */
+
+#ifdef __linux__
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <sys/mman.h>
+
+int
+get_pinned_mem ()
+{
+  int pid = getpid ();
+  char buf[100];
+  sprintf (buf, "/proc/%d/status", pid);
+
+  FILE *proc = fopen (buf, "r");
+  if (!proc)
+    abort ();
+  while (fgets (buf, 100, proc))
+    {
+      int val;
+      if (sscanf (buf, "VmLck: %d", &val))
+       {
+         fclose (proc);
+         return val;
+       }
+    }
+  abort ();
+}
+#else
+int
+get_pinned_mem ()
+{
+  return 0;
+}
+#endif
+
+#include <omp.h>
+
+/* Allocate more than a page each time, but stay within the ulimit.  */
+#define SIZE 10*1024
+
+int
+main ()
+{
+  // Sanity check
+  if (get_pinned_mem () != 0)
+    abort ();
+
+  void *p = omp_alloc (SIZE, ompx_pinned_mem_alloc);
+  if (!p)
+    abort ();
+
+  int amount = get_pinned_mem ();
+  if (amount == 0)
+    abort ();
+
+  p = omp_realloc (p, SIZE*2, ompx_pinned_mem_alloc, ompx_pinned_mem_alloc);
+
+  int amount2 = get_pinned_mem ();
+  if (amount2 <= amount)
+    abort ();
+
+  p = omp_calloc (1, SIZE, ompx_pinned_mem_alloc);
+
+  if (get_pinned_mem () <= amount2)
+    abort ();
+
+  return 0;
+}

diff --git a/libgomp/testsuite/libgomp.c/alloc-pinned-6.c b/libgomp/testsuite/libgomp.c/alloc-pinned-6.c
new file mode 100644 (file)
index 0000000..80fd37a
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-pinned-6.c
@@ -0,0 +1,96 @@
+/* { dg-do run } */
+
+/* Test that ompx_pinned_mem_alloc fails correctly.  */
+
+#ifdef __linux__
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <sys/mman.h>
+#include <sys/resource.h>
+
+int
+get_pinned_mem ()
+{
+  int pid = getpid ();
+  char buf[100];
+  sprintf (buf, "/proc/%d/status", pid);
+
+  FILE *proc = fopen (buf, "r");
+  if (!proc)
+    abort ();
+  while (fgets (buf, 100, proc))
+    {
+      int val;
+      if (sscanf (buf, "VmLck: %d", &val))
+       {
+         fclose (proc);
+         return val;
+       }
+    }
+  abort ();
+}
+
+void
+set_pin_limit (int size)
+{
+  struct rlimit limit;
+  if (getrlimit (RLIMIT_MEMLOCK, &limit))
+    abort ();
+  limit.rlim_cur = (limit.rlim_max < size ? limit.rlim_max : size);
+  if (setrlimit (RLIMIT_MEMLOCK, &limit))
+    abort ();
+}
+#else
+int
+get_pinned_mem ()
+{
+  return 0;
+}
+
+void
+set_pin_limit ()
+{
+}
+#endif
+
+#include <omp.h>
+
+/* This should be large enough to cover multiple pages.  */
+#define SIZE 10000*1024
+
+int
+main ()
+{
+  /* Ensure that the limit is smaller than the allocation.  */
+  set_pin_limit (SIZE/2);
+
+  // Sanity check
+  if (get_pinned_mem () != 0)
+    abort ();
+
+  // Should fail
+  void *p = omp_alloc (SIZE, ompx_pinned_mem_alloc);
+  if (p)
+    abort ();
+
+  // Should fail
+  p = omp_calloc (1, SIZE, ompx_pinned_mem_alloc);
+  if (p)
+    abort ();
+
+  // Should fail to realloc
+  void *notpinned = omp_alloc (SIZE, omp_default_mem_alloc);
+  p = omp_realloc (notpinned, SIZE, ompx_pinned_mem_alloc, omp_default_mem_alloc);
+  if (!notpinned || p)
+    abort ();
+
+  // No memory should have been pinned
+  int amount = get_pinned_mem ();
+  if (amount != 0)
+    abort ();
+
+  return 0;
+}

diff --git a/libgomp/testsuite/libgomp.fortran/alloc-pinned-1.f90 b/libgomp/testsuite/libgomp.fortran/alloc-pinned-1.f90
new file mode 100644 (file)
index 0000000..798dc3d
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/alloc-pinned-1.f90
@@ -0,0 +1,16 @@
+! Ensure that the ompx_pinned_mem_alloc predefined allocator is present and
+! accepted.  The majority of the functionality testing lives in the C tests.
+!
+! { dg-xfail-run-if "Pinning not implemented on this host" { ! *-*-linux-gnu } }
+
+program main
+  use omp_lib
+  use ISO_C_Binding
+  implicit none (external, type)
+
+  type(c_ptr) :: p
+
+  p = omp_alloc (10_c_size_t, ompx_pinned_mem_alloc);
+  if (.not. c_associated (p)) stop 1
+  call omp_free (p, ompx_pinned_mem_alloc);
+end program main