On 11/11/2025 11:57, Tobias Burnus wrote:
Andrew Stubbs wrote:
On 10/11/2025 10:44, Tobias Burnus wrote:
There is still no clear note in the documentation that
this allocator uses the default device when doing the
allocation – and even less so that it must be the same
device (actually: device runtime) as for the allocation.
The documentation is there now.
Thanks.
and pass it to target.c as
'gomp_managed_alloc (size, &used_device);' and
'gomp_managed_free (ptr, used_device);'
(Note: With some handling to avoid races.)
I don't think I like the idea of hidden magic that a) might prevent
clever solutions, and b) once we start doing it we can never stop. I
prefer the clear documentation together with diagnosing the cases that
we can.
Well, I am not sure whether one hidden logic is better than the other;
we could also store the value device value in the descriptor.
But that solution is also fine if sufficiently documented.
Thanks, but see below.
* * *
--- a/libgomp/env.c
+++ b/libgomp/env.c
@@ -1265,11 +1271,13 @@ parse_allocator (const char *env, const char
*val, void *const params[])
C (omp_pteam_mem_alloc, false)
C (omp_thread_mem_alloc, false)
C (ompx_gnu_pinned_mem_alloc, false)
+ C (ompx_gnu_managed_mem_alloc, false)
C (omp_default_mem_space, true)
C (omp_large_cap_mem_space, true)
C (omp_const_mem_space, true)
C (omp_high_bw_mem_space, true)
C (omp_low_lat_mem_space, true)
+ C (ompx_gnu_managed_mem_space, false)
#undef C
Not quite. The second argument is:
#define C(v, m) \
...
memspace = m; \
Thus: please use ', true)' for the last line.
Done. This was not clear to me, at first, so I've changed the macro
parameter name to remind me next time.
* * *
+@item @code{ompx_gnu_managed_mem_space} is a GNU extension that provides
...
+ already accessible on the device. If managed memory is not
supported by
+ the default device, as configured at the moment the allocator
is called,
+ then the allocator will use the fall-back setting.
Actually, on non-Linux, the normal 'malloc' is used – and not the fallback.
Example:
omp target device(dev)
{
const omp_alloctrait_t traits[]
= { { omp_atk_alignment, 256},
{omp_atk_fallback, omp_atv_abort_fb} };
omp_allocator_handle_t myalloc
= omp_init_allocator(ompx_gnu_managed_mem_space, 2, traits);
void *ptr = omp_alloc(n, ompx_gnu_managed_mem_alloc);
}
For dev == omp_initial_device (on a Linux host):
* default device == an nvidia device
→ managed memory is used (honoring the alignment)
* default device != nvidia device (e.g. the host)
→ fall back is used → ABORT
(with default_fb, 'malloc' would be used but
without the 265-bit alignment).
For dev == any non-host device
* default mem space is used ('malloc'), honoring
the alignment.
Well, that wasn't intentional. I see the default definition of the
MEMSPACE_ALLOC macros was the problem, so I've updated those, along with
the other backend routines.
I've now coded in the logic that non-standard "ompx_gnu" memory spaces
don't have a silent fall-back-to-malloc if they're not available. I
think there's an expectation that the standard-defined memory spaces are
always available (if not actually distinct), but we don't need any such
expectation for the ompx_gnu ones (of which ompx_gnu_managed_mem_space
is the first).
This can be adjusted in future, if needed, of course, but is probably a
good default for new examples of such memspaces.
The current wording does not really make his clear:
+@item @code{ompx_gnu_managed_mem_space} is a GNU extension that provides
+ managed memory accessible by both host and device (as
determined by the
+ @var{default-device-var} ICV); it is only available for
supported offload
+ targets (see @ref{Offload-Target Specifics}). This memory is
accessible
Actually, the "and device" is also not quite right. For Nvidia devices, all
Nvidia devices can access that memory – it is not device specific, either.
* * *
How about, e.g. (note also 'devices' [-s]):
@item @code{ompx_gnu_managed_mem_space} is a GNU extension that provides
managed memory accessible by both host and devices. The memory
space
is available if the offload target associated with the
@var{default-device-var} ICV supports managed memory (see
@ref{Offload-Target Specifics}). Otherwise, on Linux the
fall-back setting of the allocator is used and on other systems
the default memory space.
Done.
and continuing as in the patch:
+ This memory is accessible
+ by both the host and the device at the same address, so it need
not be
+ mapped with @code{map} clauses. Instead, use the
@code{is_device_ptr}
+ clause or @code{has_device_addr} clause to indicate that the
pointer is
+ already accessible on the device. If managed memory is not
supported by
+ the default device, as configured at the moment the allocator
is called,
+ then the allocator will use the fall-back setting. If the
default device
+ is configured differently when the memory is freed, via
@code{omp_free}
+ or @code{omp_realloc}, the result may be undefined.
Albeit the "If managed ... fall-back setting." can be removed.
I left this in because I think it's more true than before.
* * *
[AMD GPUs]
+@item Managed memory allocated with the OpenMP
+ @code{ompx_gnu_managed_mem_alloc} allocator or in the
+ @code{ompx_gnu_managed_mem_space} is not currently supported on
AMD GPU
+ devices; attempting to use it in an allocator will trigger the
fall-back
+ trait.
I think we need again "for" instead of "on" – as using
it on the device is fine, except that it will not be
managed but the default mem space. (Possibly adding 'on the host', but
it is not really needed.)
Done.
* * *
[Nvidia GPUs]
+@item Managed memory allocated with the
@code{ompx_gnu_managed_mem_alloc}
Maybe change this to 'Managed memory allocated *on* *the* *host*'?
+ allocator or in the @code{ompx_gnu_managed_mem_space} (both GNU
+ extensions) allocate memory in the CUDA Managed Memory space using
+ @code{cuMemAllocManaged}. This memory is accessible by both
the host and
+ the device at the same address, so it need not be mapped with
@code{map}
+ clauses. Instead, use the @code{is_device_ptr} clause or
+ @code{has_device_addr} clause to indicate that the pointer is
already
+ accessible on the device. The CUDA runtime will automatically
handle
+ data migration between host and device as needed.
+ If managed memory is not supported by the default device, as
configured
+ at the moment the allocator is called, then the allocator will
use the
+ fall-back setting.
I wonder whether this is needed – or the wording in the other section is
enough? I am slightly inclined of removing it.
I think people do not read the whole manual in its entirety so we should
either say everything everywhere, if it's short, or provide
cross-references, if it's not.
+ If the default device is configured differently when
+ the memory is freed, via @code{omp_free} or @code{omp_realloc},
the
+ result may be undefined.
While this one is redundant, I think it is sensible to keep it – to
avoid user surprises. It also hints at the default device in case
the user missed it in the other section.
Agreed.
* * *
All in all: LGTM with the env.c issue fixed and considering some
.texi wording changes.
Thanks for the reviews.
My v5 patch is attached.
OK now?
Andrew
From aebbafe5ae9d8334b48c53007b17f684e4e31dae Mon Sep 17 00:00:00 2001
From: Andrew Stubbs <[email protected]>
Date: Fri, 28 Jun 2024 10:24:43 +0000
Subject: [PATCH v5] openmp, nvptx: ompx_gnu_managed_mem_alloc
This adds support for using Cuda Managed Memory with omp_alloc. AMD support
will be added in a future patch.
There is one new predefined allocator, "ompx_gnu_managed_mem_alloc", plus a
corresponding memory space, which can be used to allocate memory in the
"managed" space.
The nvptx plugin is modified to make the necessary Cuda calls, via two new
(optional) plugin interfaces.
gcc/fortran/ChangeLog:
* openmp.cc (is_predefined_allocator): Use GOMP_OMP_PREDEF_ALLOC_MAX
and GOMP_OMPX_PREDEF_ALLOC_MIN/MAX instead of hardcoded values in the
comment.
include/ChangeLog:
* cuda/cuda.h (cuMemAllocManaged): Add declaration and related
CU_MEM_ATTACH_GLOBAL flag.
* gomp-constants.h (GOMP_OMPX_PREDEF_ALLOC_MAX): Update to 201.
(GOMP_OMP_PREDEF_MEMSPACE_MAX): New constant.
(GOMP_OMPX_PREDEF_MEMSPACE_MIN): New constant.
(GOMP_OMPX_PREDEF_MEMSPACE_MAX): New constant.
libgomp/ChangeLog:
* allocator.c (ompx_gnu_max_predefined_alloc): Update to
ompx_gnu_managed_mem_alloc.
(_Static_assert): Fix assertion messages for allocators and add
new assertions for memspace constants.
(omp_max_predefined_mem_space): New define.
(ompx_gnu_min_predefined_mem_space): New define.
(ompx_gnu_max_predefined_mem_space): New define.
(MEMSPACE_ALLOC): Add check for non-standard memspaces.
(MEMSPACE_CALLOC): Likewise.
(MEMSPACE_REALLOC): Likewise.
(MEMSPACE_VALIDATE): Likewise.
(predefined_ompx_gnu_alloc_mapping): Add ompx_gnu_managed_mem_space.
(omp_init_allocator): Add ompx_gnu_managed_mem_space validation.
* config/gcn/allocator.c (gcn_memspace_alloc): Add check for
non-standard memspaces.
(gcn_memspace_calloc): Likewise.
(gcn_memspace_realloc): Likewise.
(gcn_memspace_validate): Update to validate standard vs non-standard
memspaces.
* config/linux/allocator.c (linux_memspace_alloc): Add managed
memory space handling.
(linux_memspace_calloc): Likewise.
(linux_memspace_free): Likewise.
(linux_memspace_realloc): Likewise (returns NULL for fallback).
* config/nvptx/allocator.c (nvptx_memspace_alloc): Add check for
non-standard memspaces.
(nvptx_memspace_calloc): Likewise.
(nvptx_memspace_realloc): Likewise.
(nvptx_memspace_validate): Update to validate standard vs non-standard
memspaces.
* env.c (parse_allocator): Add ompx_gnu_managed_mem_alloc,
ompx_gnu_managed_mem_space, and some static asserts so I don't forget
them again.
* libgomp-plugin.h (GOMP_OFFLOAD_managed_alloc): New declaration.
(GOMP_OFFLOAD_managed_free): New declaration.
* libgomp.h (gomp_managed_alloc): New declaration.
(gomp_managed_free): New declaration.
(struct gomp_device_descr): Add managed_alloc_func and
managed_free_func fields.
* libgomp.texi: Document ompx_gnu_managed_mem_alloc and
ompx_gnu_managed_mem_space, add C++ template documentation, and
describe NVPTX and AMD support.
* omp.h.in: Add ompx_gnu_managed_mem_space and
ompx_gnu_managed_mem_alloc enumerators, and gnu_managed_mem C++
allocator template.
* omp_lib.f90.in: Add Fortran bindings for new allocator and
memory space.
* omp_lib.h.in: Likewise.
* plugin/cuda-lib.def: Add cuMemAllocManaged.
* plugin/plugin-nvptx.c (nvptx_alloc): Add managed parameter to
support cuMemAllocManaged.
(GOMP_OFFLOAD_alloc): Move contents to ...
(cleanup_and_alloc): ... this new function, and add managed support.
(GOMP_OFFLOAD_managed_alloc): New function.
(GOMP_OFFLOAD_managed_free): New function.
* target.c (gomp_managed_alloc): New function.
(gomp_managed_free): New function.
(gomp_load_plugin_for_device): Load optional managed_alloc
and managed_free plugin APIs.
* testsuite/lib/libgomp.exp: Add check_effective_target_omp_managedmem.
* testsuite/libgomp.c++/alloc-managed-1.C: New test.
* testsuite/libgomp.c/alloc-managed-1.c: New test.
* testsuite/libgomp.c/alloc-managed-2.c: New test.
* testsuite/libgomp.c/alloc-managed-3.c: New test.
* testsuite/libgomp.c/alloc-managed-4.c: New test.
* testsuite/libgomp.fortran/alloc-managed-1.f90: New test.
Co-authored-by: Kwok Cheung Yeung <[email protected]>
Co-authored-by: Thomas Schwinge <[email protected]>
---
gcc/fortran/openmp.cc | 6 +--
include/cuda/cuda.h | 5 ++
include/gomp-constants.h | 7 ++-
libgomp/allocator.c | 47 +++++++++++++++----
libgomp/config/gcn/allocator.c | 20 +++++++-
libgomp/config/linux/allocator.c | 26 ++++++++--
libgomp/config/nvptx/allocator.c | 22 +++++++--
libgomp/env.c | 12 ++++-
libgomp/libgomp-plugin.h | 2 +
libgomp/libgomp.h | 4 ++
libgomp/libgomp.texi | 34 ++++++++++++++
libgomp/omp.h.in | 6 +++
libgomp/omp_lib.f90.in | 4 ++
libgomp/omp_lib.h.in | 4 ++
libgomp/plugin/cuda-lib.def | 1 +
libgomp/plugin/plugin-nvptx.c | 32 ++++++++++---
libgomp/target.c | 42 +++++++++++++++++
libgomp/testsuite/lib/libgomp.exp | 9 ++++
.../testsuite/libgomp.c++/alloc-managed-1.C | 35 ++++++++++++++
libgomp/testsuite/libgomp.c/alloc-managed-1.c | 28 +++++++++++
libgomp/testsuite/libgomp.c/alloc-managed-2.c | 38 +++++++++++++++
libgomp/testsuite/libgomp.c/alloc-managed-3.c | 44 +++++++++++++++++
libgomp/testsuite/libgomp.c/alloc-managed-4.c | 22 +++++++++
.../libgomp.fortran/alloc-managed-1.f90 | 29 ++++++++++++
24 files changed, 447 insertions(+), 32 deletions(-)
create mode 100644 libgomp/testsuite/libgomp.c++/alloc-managed-1.C
create mode 100644 libgomp/testsuite/libgomp.c/alloc-managed-1.c
create mode 100644 libgomp/testsuite/libgomp.c/alloc-managed-2.c
create mode 100644 libgomp/testsuite/libgomp.c/alloc-managed-3.c
create mode 100644 libgomp/testsuite/libgomp.c/alloc-managed-4.c
create mode 100644 libgomp/testsuite/libgomp.fortran/alloc-managed-1.f90
diff --git a/gcc/fortran/openmp.cc b/gcc/fortran/openmp.cc
index f5db9a81ea6..bae4e479cf4 100644
--- a/gcc/fortran/openmp.cc
+++ b/gcc/fortran/openmp.cc
@@ -8359,9 +8359,9 @@ resolve_omp_udr_clause (gfc_omp_namelist *n, gfc_namespace *ns,
}
/* Assume that a constant expression in the range 1 (omp_default_mem_alloc)
- to 8 (omp_thread_mem_alloc) range, or 200 (ompx_gnu_pinned_mem_alloc) is
- fine. The original symbol name is already lost during matching via
- gfc_match_expr. */
+ to GOMP_OMP_PREDEF_ALLOC_MAX, or GOMP_OMPX_PREDEF_ALLOC_MIN to
+ GOMP_OMPX_PREDEF_ALLOC_MAX is fine. The original symbol name is already
+ lost during matching via gfc_match_expr. */
static bool
is_predefined_allocator (gfc_expr *expr)
{
diff --git a/include/cuda/cuda.h b/include/cuda/cuda.h
index 6be1ac0ab43..28510a3150c 100644
--- a/include/cuda/cuda.h
+++ b/include/cuda/cuda.h
@@ -87,6 +87,10 @@ typedef enum {
CU_DEVICE_ATTRIBUTE_PAGEABLE_MEMORY_ACCESS = 88
} CUdevice_attribute;
+typedef enum {
+ CU_MEM_ATTACH_GLOBAL = 0x1
+} CUmemAttach_flags;
+
enum {
CU_EVENT_DEFAULT = 0,
CU_EVENT_DISABLE_TIMING = 2
@@ -254,6 +258,7 @@ CUresult cuMemAlloc (CUdeviceptr *, size_t);
#define cuMemAllocHost cuMemAllocHost_v2
CUresult cuMemAllocHost (void **, size_t);
CUresult cuMemHostAlloc (void **, size_t, unsigned int);
+CUresult cuMemAllocManaged(CUdeviceptr *, size_t, unsigned int);
CUresult cuMemcpy (CUdeviceptr, CUdeviceptr, size_t);
CUresult cuMemcpyPeer (CUdeviceptr, CUcontext, CUdeviceptr, CUcontext, size_t);
CUresult cuMemcpyPeerAsync (CUdeviceptr, CUcontext, CUdeviceptr, CUcontext, size_t, CUstream);
diff --git a/include/gomp-constants.h b/include/gomp-constants.h
index 963436aee56..db55b260053 100644
--- a/include/gomp-constants.h
+++ b/include/gomp-constants.h
@@ -395,7 +395,12 @@ enum gomp_map_kind
/* Predefined allocator value ranges. */
#define GOMP_OMP_PREDEF_ALLOC_MAX 8
#define GOMP_OMPX_PREDEF_ALLOC_MIN 200
-#define GOMP_OMPX_PREDEF_ALLOC_MAX 200
+#define GOMP_OMPX_PREDEF_ALLOC_MAX 201
+
+/* Predefined memspace value ranges. */
+#define GOMP_OMP_PREDEF_MEMSPACE_MAX 4
+#define GOMP_OMPX_PREDEF_MEMSPACE_MIN 200
+#define GOMP_OMPX_PREDEF_MEMSPACE_MAX 200
/* Predefined allocator with access == thread. */
#define GOMP_OMP_PREDEF_ALLOC_THREADS 8
diff --git a/libgomp/allocator.c b/libgomp/allocator.c
index 4a683d90bba..44c41cadd0b 100644
--- a/libgomp/allocator.c
+++ b/libgomp/allocator.c
@@ -100,34 +100,57 @@ GOMP_is_alloc (void *ptr)
#define omp_max_predefined_alloc omp_thread_mem_alloc
#define ompx_gnu_min_predefined_alloc ompx_gnu_pinned_mem_alloc
-#define ompx_gnu_max_predefined_alloc ompx_gnu_pinned_mem_alloc
+#define ompx_gnu_max_predefined_alloc ompx_gnu_managed_mem_alloc
_Static_assert (GOMP_OMP_PREDEF_ALLOC_MAX == omp_thread_mem_alloc,
"GOMP_OMP_PREDEF_ALLOC_MAX == omp_thread_mem_alloc");
_Static_assert (GOMP_OMPX_PREDEF_ALLOC_MIN == ompx_gnu_min_predefined_alloc,
- "GOMP_OMP_PREDEF_ALLOC_MAX == omp_thread_mem_alloc");
+ "GOMP_OMPX_PREDEF_ALLOC_MIN == ompx_gnu_min_predefined_alloc");
_Static_assert (GOMP_OMPX_PREDEF_ALLOC_MAX == ompx_gnu_max_predefined_alloc,
- "GOMP_OMP_PREDEF_ALLOC_MAX == omp_thread_mem_alloc");
+ "GOMP_OMPX_PREDEF_ALLOC_MAX == ompx_gnu_max_predefined_alloc");
_Static_assert (GOMP_OMP_PREDEF_ALLOC_THREADS == omp_thread_mem_alloc,
"GOMP_OMP_PREDEF_ALLOC_THREADS == omp_thread_mem_alloc");
+#define omp_max_predefined_mem_space omp_low_lat_mem_space
+#define ompx_gnu_min_predefined_mem_space ompx_gnu_managed_mem_space
+#define ompx_gnu_max_predefined_mem_space ompx_gnu_managed_mem_space
+
+_Static_assert (GOMP_OMP_PREDEF_MEMSPACE_MAX == omp_max_predefined_mem_space,
+ "GOMP_OMP_PREDEF_MEMSPACE_MAX == omp_max_predefined_mem_space");
+_Static_assert (GOMP_OMPX_PREDEF_MEMSPACE_MIN == ompx_gnu_min_predefined_mem_space,
+ "GOMP_OMPX_PREDEF_MEMSPACE_MIN == ompx_gnu_min_predefined_mem_space");
+_Static_assert (GOMP_OMPX_PREDEF_MEMSPACE_MAX == ompx_gnu_max_predefined_mem_space,
+ "GOMP_OMPX_PREDEF_MEMSPACE_MAX == ompx_gnu_max_predefined_mem_space");
+
+#if 0 /* For testing the fall-back macros compile, only. */
+#undef MEMSPACE_ALLOC
+#undef MEMSPACE_CALLOC
+#undef MEMSPACE_REALLOC
+#undef MEMSPACE_FREE
+#undef MEMSPACE_VALIDATE
+#endif
+
/* These macros may be overridden in config/<target>/allocator.c.
The defaults (no override) are to return NULL for pinned memory requests
- and pass through to the regular OS calls otherwise.
+ or non-standard memory spaces (these need a deliberate implementation), and
+ pass through to the regular OS calls otherwise.
The following definitions (ab)use comma operators to avoid unused
variable errors. */
#ifndef MEMSPACE_ALLOC
#define MEMSPACE_ALLOC(MEMSPACE, SIZE, PIN) \
- (PIN ? NULL : malloc (((void)(MEMSPACE), (SIZE))))
+ ((PIN) || (MEMSPACE) > GOMP_OMP_PREDEF_MEMSPACE_MAX \
+ ? NULL : malloc (((void)(MEMSPACE), (SIZE))))
#endif
#ifndef MEMSPACE_CALLOC
#define MEMSPACE_CALLOC(MEMSPACE, SIZE, PIN) \
- (PIN ? NULL : calloc (1, (((void)(MEMSPACE), (SIZE)))))
+ ((PIN) || (MEMSPACE) > GOMP_OMP_PREDEF_MEMSPACE_MAX \
+ ? NULL : calloc (1, (((void)(MEMSPACE), (SIZE)))))
#endif
#ifndef MEMSPACE_REALLOC
#define MEMSPACE_REALLOC(MEMSPACE, ADDR, OLDSIZE, SIZE, OLDPIN, PIN) \
- ((PIN) || (OLDPIN) ? NULL \
- : realloc (ADDR, (((void)(MEMSPACE), (void)(OLDSIZE), (SIZE)))))
+ ((PIN) || (OLDPIN) || (MEMSPACE) > GOMP_OMP_PREDEF_MEMSPACE_MAX \
+ ? NULL \
+ : realloc (ADDR, (((void)(MEMSPACE), (void)(OLDSIZE), (SIZE)))))
#endif
#ifndef MEMSPACE_FREE
#define MEMSPACE_FREE(MEMSPACE, ADDR, SIZE, PIN) \
@@ -135,7 +158,8 @@ _Static_assert (GOMP_OMP_PREDEF_ALLOC_THREADS == omp_thread_mem_alloc,
#endif
#ifndef MEMSPACE_VALIDATE
#define MEMSPACE_VALIDATE(MEMSPACE, ACCESS, PIN) \
- (PIN ? 0 : ((void)(MEMSPACE), (void)(ACCESS), 1))
+ ((PIN) || (MEMSPACE) > GOMP_OMP_PREDEF_MEMSPACE_MAX \
+ ? 0 : ((void)(MEMSPACE), (void)(ACCESS), 1))
#endif
/* Map the predefined allocators to the correct memory space.
@@ -155,6 +179,7 @@ static const omp_memspace_handle_t predefined_omp_alloc_mapping[] = {
};
static const omp_memspace_handle_t predefined_ompx_gnu_alloc_mapping[] = {
omp_default_mem_space, /* ompx_gnu_pinned_mem_alloc. */
+ ompx_gnu_managed_mem_space, /* ompx_gnu_managed_mem_alloc. */
};
#define ARRAY_SIZE(A) (sizeof (A) / sizeof ((A)[0]))
@@ -389,7 +414,9 @@ omp_init_allocator (omp_memspace_handle_t memspace, int ntraits,
struct omp_allocator_data *ret;
int i;
- if (memspace > omp_low_lat_mem_space)
+ if (memspace > omp_max_predefined_mem_space
+ && (memspace < ompx_gnu_min_predefined_mem_space
+ || memspace > ompx_gnu_max_predefined_mem_space))
return omp_null_allocator;
for (i = 0; i < ntraits; i++)
switch (traits[i].key)
diff --git a/libgomp/config/gcn/allocator.c b/libgomp/config/gcn/allocator.c
index 92aa2db2cc6..969cfa9ccd9 100644
--- a/libgomp/config/gcn/allocator.c
+++ b/libgomp/config/gcn/allocator.c
@@ -56,8 +56,12 @@ gcn_memspace_alloc (omp_memspace_handle_t memspace, size_t size)
return __gcn_lowlat_alloc (shared_pool, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side amdgcn. */
+ return NULL;
else
return malloc (size);
+
}
static void *
@@ -69,6 +73,9 @@ gcn_memspace_calloc (omp_memspace_handle_t memspace, size_t size)
return __gcn_lowlat_calloc (shared_pool, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side amdgcn. */
+ return NULL;
else
return calloc (1, size);
}
@@ -96,6 +103,9 @@ gcn_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
return __gcn_lowlat_realloc (shared_pool, addr, oldsize, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side amdgcn. */
+ return NULL;
else
return realloc (addr, size);
}
@@ -105,8 +115,14 @@ gcn_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);
+ if (memspace == omp_low_lat_mem_space
+ && access == omp_atv_all)
+ return false;
+
+ /* Otherwise, standard memspaces are accepted, even when we don't have
+ anything special to do with them, and non-standard memspaces are assumed
+ to need explicit support. */
+ return (memspace <= GOMP_OMP_PREDEF_MEMSPACE_MAX);
}
#define MEMSPACE_ALLOC(MEMSPACE, SIZE, PIN) \
diff --git a/libgomp/config/linux/allocator.c b/libgomp/config/linux/allocator.c
index f957bb3421a..c144c597283 100644
--- a/libgomp/config/linux/allocator.c
+++ b/libgomp/config/linux/allocator.c
@@ -80,7 +80,9 @@ linux_memspace_alloc (omp_memspace_handle_t memspace, size_t size, int pin,
{
void *addr = NULL;
- if (pin)
+ if (memspace == ompx_gnu_managed_mem_space)
+ addr = gomp_managed_alloc (size);
+ else if (pin)
{
int using_device = __atomic_load_n (&using_device_for_page_locked,
MEMMODEL_RELAXED);
@@ -155,7 +157,15 @@ linux_memspace_alloc (omp_memspace_handle_t memspace, size_t size, int pin,
static void *
linux_memspace_calloc (omp_memspace_handle_t memspace, size_t size, int pin)
{
- if (pin)
+ if (memspace == ompx_gnu_managed_mem_space)
+ {
+ void *ret = gomp_managed_alloc (size);
+ if (!ret)
+ return NULL;
+ memset (ret, 0, size);
+ return ret;
+ }
+ else if (pin)
return linux_memspace_alloc (memspace, size, pin, true);
else
return calloc (1, size);
@@ -165,7 +175,9 @@ static void
linux_memspace_free (omp_memspace_handle_t memspace, void *addr, size_t size,
int pin)
{
- if (pin)
+ if (memspace == ompx_gnu_managed_mem_space)
+ gomp_managed_free (addr);
+ else if (pin)
{
int using_device
= __atomic_load_n (&using_device_for_page_locked,
@@ -186,7 +198,10 @@ static void *
linux_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
size_t oldsize, size_t size, int oldpin, int pin)
{
- if (oldpin && pin)
+ if (memspace == ompx_gnu_managed_mem_space)
+ /* Realloc is not implemented for device Managed Memory. */
+ ;
+ else if (oldpin && pin)
{
int using_device
= __atomic_load_n (&using_device_for_page_locked,
@@ -221,7 +236,8 @@ linux_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
static int
linux_memspace_validate (omp_memspace_handle_t, unsigned, int)
{
- /* Everything should be accepted on Linux, including pinning. */
+ /* Everything should be accepted on Linux, including pinning and
+ non-standard memspaces. */
return 1;
}
diff --git a/libgomp/config/nvptx/allocator.c b/libgomp/config/nvptx/allocator.c
index 7e9e343d2a9..8bbc14a49db 100644
--- a/libgomp/config/nvptx/allocator.c
+++ b/libgomp/config/nvptx/allocator.c
@@ -61,6 +61,9 @@ nvptx_memspace_alloc (omp_memspace_handle_t memspace, size_t size)
return __nvptx_lowlat_alloc (shared_pool, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side nvptx. */
+ return NULL;
else
return malloc (size);
}
@@ -75,6 +78,9 @@ nvptx_memspace_calloc (omp_memspace_handle_t memspace, size_t size)
return __nvptx_lowlat_calloc (shared_pool, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side nvptx. */
+ return NULL;
else
return calloc (1, size);
}
@@ -104,6 +110,9 @@ nvptx_memspace_realloc (omp_memspace_handle_t memspace, void *addr,
return __nvptx_lowlat_realloc (shared_pool, addr, oldsize, size);
}
+ else if (memspace > GOMP_OMP_PREDEF_MEMSPACE_MAX)
+ /* No non-standard memspaces are implemented for device-side nvptx. */
+ return NULL;
else
return realloc (addr, size);
}
@@ -115,12 +124,19 @@ nvptx_memspace_validate (omp_memspace_handle_t memspace, unsigned access)
|| (__PTX_ISA_VERSION_MAJOR__ == 4 && __PTX_ISA_VERSION_MINOR >= 1)
/* 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);
+ if (memspace == omp_low_lat_mem_space
+ && access == omp_atv_all)
+ return false;
#else
/* Low-latency memory is not available before PTX 4.1. */
- return (memspace != omp_low_lat_mem_space);
+ if (memspace == omp_low_lat_mem_space)
+ return false;
#endif
+
+ /* Otherwise, standard memspaces are accepted, even when we don't have
+ anything special to do with them, and non-standard memspaces are assumed
+ to need explicit support. */
+ return (memspace <= GOMP_OMP_PREDEF_MEMSPACE_MAX);
}
#define MEMSPACE_ALLOC(MEMSPACE, SIZE, PIN) \
diff --git a/libgomp/env.c b/libgomp/env.c
index f63a36afdd2..48bb7890e7b 100644
--- a/libgomp/env.c
+++ b/libgomp/env.c
@@ -1231,6 +1231,12 @@ parse_affinity (bool ignore)
return false;
}
+/* These are reminders to add new allocators to parse_allocator. */
+_Static_assert (GOMP_OMP_PREDEF_ALLOC_MAX == omp_thread_mem_alloc);
+_Static_assert (GOMP_OMPX_PREDEF_ALLOC_MAX == ompx_gnu_managed_mem_alloc);
+_Static_assert (GOMP_OMP_PREDEF_MEMSPACE_MAX == omp_low_lat_mem_space);
+_Static_assert (GOMP_OMPX_PREDEF_MEMSPACE_MAX == ompx_gnu_managed_mem_space);
+
/* Parse the OMP_ALLOCATOR environment variable and return the value. */
static bool
parse_allocator (const char *env, const char *val, void *const params[])
@@ -1249,12 +1255,12 @@ parse_allocator (const char *env, const char *val, void *const params[])
++val;
if (0)
;
-#define C(v, m) \
+#define C(v, is_memspace) \
else if (strncasecmp (val, #v, sizeof (#v) - 1) == 0) \
{ \
*ret = v; \
val += sizeof (#v) - 1; \
- memspace = m; \
+ memspace = is_memspace; \
}
C (omp_default_mem_alloc, false)
C (omp_large_cap_mem_alloc, false)
@@ -1265,11 +1271,13 @@ parse_allocator (const char *env, const char *val, void *const params[])
C (omp_pteam_mem_alloc, false)
C (omp_thread_mem_alloc, false)
C (ompx_gnu_pinned_mem_alloc, false)
+ C (ompx_gnu_managed_mem_alloc, false)
C (omp_default_mem_space, true)
C (omp_large_cap_mem_space, true)
C (omp_const_mem_space, true)
C (omp_high_bw_mem_space, true)
C (omp_low_lat_mem_space, true)
+ C (ompx_gnu_managed_mem_space, true)
#undef C
else
goto invalid;
diff --git a/libgomp/libgomp-plugin.h b/libgomp/libgomp-plugin.h
index f2baed9bad9..5b4704484dd 100644
--- a/libgomp/libgomp-plugin.h
+++ b/libgomp/libgomp-plugin.h
@@ -171,6 +171,8 @@ extern int GOMP_OFFLOAD_load_image (int, unsigned, const void *,
extern bool GOMP_OFFLOAD_unload_image (int, unsigned, const void *);
extern void *GOMP_OFFLOAD_alloc (int, size_t);
extern bool GOMP_OFFLOAD_free (int, void *);
+extern void *GOMP_OFFLOAD_managed_alloc (int, size_t);
+extern bool GOMP_OFFLOAD_managed_free (int, void *);
extern bool GOMP_OFFLOAD_page_locked_host_alloc (void **, size_t);
extern bool GOMP_OFFLOAD_page_locked_host_free (void *);
extern bool GOMP_OFFLOAD_dev2host (int, void *, const void *, size_t);
diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h
index 3d406be175e..ff445d1e90c 100644
--- a/libgomp/libgomp.h
+++ b/libgomp/libgomp.h
@@ -1135,6 +1135,8 @@ extern int gomp_get_num_devices (void);
extern bool gomp_target_task_fn (void *);
extern void gomp_target_rev (uint64_t, uint64_t, uint64_t, uint64_t, uint64_t,
int, struct goacc_asyncqueue *);
+extern void *gomp_managed_alloc (size_t size);
+extern void gomp_managed_free (void *device_ptr);
extern bool gomp_page_locked_host_alloc (void **, size_t);
extern void gomp_page_locked_host_free (void *);
@@ -1421,6 +1423,8 @@ struct gomp_device_descr
__typeof (GOMP_OFFLOAD_unload_image) *unload_image_func;
__typeof (GOMP_OFFLOAD_alloc) *alloc_func;
__typeof (GOMP_OFFLOAD_free) *free_func;
+ __typeof (GOMP_OFFLOAD_managed_alloc) *managed_alloc_func;
+ __typeof (GOMP_OFFLOAD_managed_free) *managed_free_func;
__typeof (GOMP_OFFLOAD_page_locked_host_alloc) *page_locked_host_alloc_func;
__typeof (GOMP_OFFLOAD_page_locked_host_free) *page_locked_host_free_func;
__typeof (GOMP_OFFLOAD_dev2host) *dev2host_func;
diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi
index 76a0162f814..733b5262ca3 100644
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
@@ -6890,6 +6890,7 @@ GCC supports the following predefined allocators and predefined memory spaces:
@item omp_pteam_mem_alloc @tab omp_low_lat_mem_space (implementation defined)
@item omp_thread_mem_alloc @tab omp_low_lat_mem_space (implementation defined)
@item ompx_gnu_pinned_mem_alloc @tab omp_default_mem_space (GNU extension)
+@item ompx_gnu_managed_mem_alloc @tab ompx_gnu_managed_mem_space (GNU extension)
@end multitable
Each predefined allocator, including @code{omp_null_allocator}, has a corresponding
@@ -6917,6 +6918,7 @@ The following allocator templates are supported:
@item omp_pteam_mem_alloc @tab omp::allocator::pteam_mem
@item omp_thread_mem_alloc @tab omp::allocator::thread_mem
@item ompx_gnu_pinned_mem_alloc @tab ompx::allocator::gnu_pinned_mem
+@item ompx_gnu_managed_mem_alloc @tab ompx::allocator::gnu_managed_mem
@end multitable
The following traits are available when constructing a new allocator;
@@ -6976,6 +6978,19 @@ For the memory spaces, the following applies:
unless the memkind library is available
@item @code{omp_high_bw_mem_space} maps to @code{omp_default_mem_space},
unless the memkind library is available
+@item @code{ompx_gnu_managed_mem_space} is a GNU extension that provides
+ managed memory accessible by both host and devices. The memory space is
+ available if the offload target associated with the
+ @var{default-device-var} ICV supports managed memory (see
+ @ref{Offload-Target Specifics}). This memory is accessible by both the
+ host and the device at the same address, so it need not be mapped with
+ @code{map} clauses. Instead, use the @code{is_device_ptr} clause or
+ @code{has_device_addr} clause to indicate that the pointer is already
+ accessible on the device. If managed memory is not supported by the
+ default device, as configured at the moment the allocator is called, then
+ the allocator will use the fall-back setting. If the default device is
+ configured differently when the memory is freed, via @code{omp_free} or
+ @code{omp_realloc}, the result may be undefined.
@end itemize
On Linux systems, where the @uref{https://github.com/memkind/memkind, memkind
@@ -7135,6 +7150,11 @@ The implementation remark:
a performance boost for NVPTX offload code and also allows unlimited use
of pinned memory regardless of the OS @code{ulimit}/@code{rlimit}
settings.
+@item Managed memory allocated with the OpenMP
+ @code{ompx_gnu_managed_mem_alloc} allocator or in the
+ @code{ompx_gnu_managed_mem_space} is not currently supported for AMD GPU
+ devices; attempting to use it in an allocator will trigger the fall-back
+ trait.
@item The OpenMP routines @code{omp_target_memcpy_rect} and
@code{omp_target_memcpy_rect_async} and the @code{target update}
directive for non-contiguous list items use the 3D memory-copy function
@@ -7297,6 +7317,20 @@ The implementation remark:
@code{omp_thread_mem_alloc}, all use low-latency memory as first
preference, and fall back to main graphics memory when the low-latency
pool is exhausted.
+@item Managed memory allocated on the host with the
+ @code{ompx_gnu_managed_mem_alloc} allocator or in the
+ @code{ompx_gnu_managed_mem_space} (both GNU extensions) allocate memory
+ in the CUDA Managed Memory space using @code{cuMemAllocManaged}. This
+ memory is accessible by both the host and the device at the same address,
+ so it need not be mapped with @code{map} clauses. Instead, use the
+ @code{is_device_ptr} clause or @code{has_device_addr} clause to indicate
+ that the pointer is already accessible on the device. The CUDA runtime
+ will automatically handle data migration between host and device as
+ needed. If managed memory is not supported by the default device, as
+ configured at the moment the allocator is called, then the allocator will
+ use the fall-back setting. If the default device is configured
+ differently when the memory is freed, via @code{omp_free} or
+ @code{omp_realloc}, the result may be undefined.
@item The OpenMP routines @code{omp_target_memcpy_rect} and
@code{omp_target_memcpy_rect_async} and the @code{target update}
directive for non-contiguous list items use the 2D and 3D memory-copy
diff --git a/libgomp/omp.h.in b/libgomp/omp.h.in
index 60cb2b21be7..74c074c31c8 100644
--- a/libgomp/omp.h.in
+++ b/libgomp/omp.h.in
@@ -121,6 +121,7 @@ typedef enum omp_memspace_handle_t __GOMP_UINTPTR_T_ENUM
omp_const_mem_space = 2,
omp_high_bw_mem_space = 3,
omp_low_lat_mem_space = 4,
+ ompx_gnu_managed_mem_space = 200,
__omp_memspace_handle_t_max__ = __UINTPTR_MAX__
} omp_memspace_handle_t;
@@ -136,6 +137,7 @@ typedef enum omp_allocator_handle_t __GOMP_UINTPTR_T_ENUM
omp_pteam_mem_alloc = 7,
omp_thread_mem_alloc = 8,
ompx_gnu_pinned_mem_alloc = 200,
+ ompx_gnu_managed_mem_alloc = 201,
__omp_allocator_handle_t_max__ = __UINTPTR_MAX__
} omp_allocator_handle_t;
@@ -562,6 +564,10 @@ template <typename __T>
struct gnu_pinned_mem
: omp::allocator::__detail::__allocator_templ <__T,
ompx_gnu_pinned_mem_alloc> {};
+template <typename __T>
+struct gnu_managed_mem
+ : omp::allocator::__detail::__allocator_templ <__T,
+ ompx_gnu_managed_mem_alloc> {};
} /* namespace allocator */
diff --git a/libgomp/omp_lib.f90.in b/libgomp/omp_lib.f90.in
index ce866c00121..1d8cbafaa42 100644
--- a/libgomp/omp_lib.f90.in
+++ b/libgomp/omp_lib.f90.in
@@ -164,6 +164,8 @@
parameter :: omp_thread_mem_alloc = 8
integer (kind=omp_allocator_handle_kind), &
parameter :: ompx_gnu_pinned_mem_alloc = 200
+ integer (kind=omp_allocator_handle_kind), &
+ parameter :: ompx_gnu_managed_mem_alloc = 201
integer (omp_memspace_handle_kind), &
parameter :: omp_default_mem_space = 0
integer (omp_memspace_handle_kind), &
@@ -174,6 +176,8 @@
parameter :: omp_high_bw_mem_space = 3
integer (omp_memspace_handle_kind), &
parameter :: omp_low_lat_mem_space = 4
+ integer (omp_memspace_handle_kind), &
+ parameter :: ompx_gnu_managed_mem_space = 200
integer, parameter :: omp_initial_device = -1
integer, parameter :: omp_invalid_device = -4
integer (omp_interop_kind), &
diff --git a/libgomp/omp_lib.h.in b/libgomp/omp_lib.h.in
index 9047095c5e0..7c158de5667 100644
--- a/libgomp/omp_lib.h.in
+++ b/libgomp/omp_lib.h.in
@@ -162,6 +162,7 @@
integer (omp_allocator_handle_kind) omp_pteam_mem_alloc
integer (omp_allocator_handle_kind) omp_thread_mem_alloc
integer (omp_allocator_handle_kind) ompx_gnu_pinned_mem_alloc
+ integer (omp_allocator_handle_kind) ompx_gnu_managed_mem_alloc
parameter (omp_null_allocator = 0)
parameter (omp_default_mem_alloc = 1)
parameter (omp_large_cap_mem_alloc = 2)
@@ -172,16 +173,19 @@
parameter (omp_pteam_mem_alloc = 7)
parameter (omp_thread_mem_alloc = 8)
parameter (ompx_gnu_pinned_mem_alloc = 200)
+ parameter (ompx_gnu_managed_mem_alloc = 201)
integer (omp_memspace_handle_kind) omp_default_mem_space
integer (omp_memspace_handle_kind) omp_large_cap_mem_space
integer (omp_memspace_handle_kind) omp_const_mem_space
integer (omp_memspace_handle_kind) omp_high_bw_mem_space
integer (omp_memspace_handle_kind) omp_low_lat_mem_space
+ integer (omp_memspace_handle_kind) ompx_gnu_managed_mem_space
parameter (omp_default_mem_space = 0)
parameter (omp_large_cap_mem_space = 1)
parameter (omp_const_mem_space = 2)
parameter (omp_high_bw_mem_space = 3)
parameter (omp_low_lat_mem_space = 4)
+ parameter (ompx_gnu_managed_mem_space = 200)
integer omp_initial_device, omp_invalid_device
parameter (omp_initial_device = -1)
parameter (omp_invalid_device = -4)
diff --git a/libgomp/plugin/cuda-lib.def b/libgomp/plugin/cuda-lib.def
index 7f4ddcc6bd1..67c783d8566 100644
--- a/libgomp/plugin/cuda-lib.def
+++ b/libgomp/plugin/cuda-lib.def
@@ -33,6 +33,7 @@ CUDA_ONE_CALL (cuLinkDestroy)
CUDA_ONE_CALL (cuMemAlloc)
CUDA_ONE_CALL (cuMemAllocHost)
CUDA_ONE_CALL (cuMemHostAlloc)
+CUDA_ONE_CALL (cuMemAllocManaged)
CUDA_ONE_CALL (cuMemcpy)
CUDA_ONE_CALL (cuMemcpyDtoDAsync)
CUDA_ONE_CALL (cuMemcpyDtoH)
diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index 5ad66688e7e..dd8bcf9c507 100644
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -1133,11 +1133,13 @@ nvptx_stacks_free (struct ptx_device *ptx_dev, bool force)
}
static void *
-nvptx_alloc (size_t s, bool suppress_errors)
+nvptx_alloc (size_t s, bool suppress_errors, bool managed)
{
CUdeviceptr d;
- CUresult r = CUDA_CALL_NOCHECK (cuMemAlloc, &d, s);
+ CUresult r = (managed ? CUDA_CALL_NOCHECK (cuMemAllocManaged, &d, s,
+ CU_MEM_ATTACH_GLOBAL)
+ : CUDA_CALL_NOCHECK (cuMemAlloc, &d, s));
if (suppress_errors && r == CUDA_ERROR_OUT_OF_MEMORY)
return NULL;
else if (r != CUDA_SUCCESS)
@@ -1843,8 +1845,8 @@ GOMP_OFFLOAD_unload_image (int ord, unsigned version, const void *target_data)
return ret;
}
-void *
-GOMP_OFFLOAD_alloc (int ord, size_t size)
+static void *
+cleanup_and_alloc (int ord, size_t size, bool managed)
{
if (!nvptx_attach_host_thread_to_device (ord))
return NULL;
@@ -1867,7 +1869,7 @@ GOMP_OFFLOAD_alloc (int ord, size_t size)
blocks = tmp;
}
- void *d = nvptx_alloc (size, true);
+ void *d = nvptx_alloc (size, true, managed);
if (d)
return d;
else
@@ -1875,10 +1877,22 @@ GOMP_OFFLOAD_alloc (int ord, size_t size)
/* Memory allocation failed. Try freeing the stacks block, and
retrying. */
nvptx_stacks_free (ptx_dev, true);
- return nvptx_alloc (size, false);
+ return nvptx_alloc (size, false, managed);
}
}
+void *
+GOMP_OFFLOAD_alloc (int ord, size_t size)
+{
+ return cleanup_and_alloc (ord, size, false);
+}
+
+void *
+GOMP_OFFLOAD_managed_alloc (int ord, size_t size)
+{
+ return cleanup_and_alloc (ord, size, true);
+}
+
bool
GOMP_OFFLOAD_free (int ord, void *ptr)
{
@@ -1886,6 +1900,12 @@ GOMP_OFFLOAD_free (int ord, void *ptr)
&& nvptx_free (ptr, ptx_devices[ord]));
}
+bool
+GOMP_OFFLOAD_managed_free (int ord, void *ptr)
+{
+ return GOMP_OFFLOAD_free (ord, ptr);
+}
+
bool
GOMP_OFFLOAD_page_locked_host_alloc (void **ptr, size_t size)
{
diff --git a/libgomp/target.c b/libgomp/target.c
index ac5b4b0b720..859513b13b2 100644
--- a/libgomp/target.c
+++ b/libgomp/target.c
@@ -4697,6 +4697,46 @@ omp_target_free (void *device_ptr, int device_num)
gomp_mutex_unlock (&devicep->lock);
}
+void *
+gomp_managed_alloc (size_t size)
+{
+ struct gomp_task_icv *icv = gomp_icv (false);
+ struct gomp_device_descr *devicep = resolve_device (icv->default_device_var,
+ false);
+ if (devicep == NULL)
+ return NULL;
+
+ void *ret = NULL;
+ gomp_mutex_lock (&devicep->lock);
+ if (devicep->managed_alloc_func)
+ ret = devicep->managed_alloc_func (devicep->target_id, size);
+ gomp_mutex_unlock (&devicep->lock);
+ return ret;
+}
+
+void
+gomp_managed_free (void *device_ptr)
+{
+ if (device_ptr == NULL)
+ return;
+
+ struct gomp_task_icv *icv = gomp_icv (false);
+ struct gomp_device_descr *devicep = resolve_device (icv->default_device_var,
+ false);
+ if (devicep == NULL)
+ gomp_fatal ("attempted to free managed memory at %p, but the default "
+ "device is set to the host device", device_ptr);
+
+ gomp_mutex_lock (&devicep->lock);
+ if (!devicep->managed_free_func
+ || !devicep->managed_free_func (devicep->target_id, device_ptr))
+ {
+ gomp_mutex_unlock (&devicep->lock);
+ gomp_fatal ("error in freeing managed memory block at %p", device_ptr);
+ }
+ gomp_mutex_unlock (&devicep->lock);
+}
+
/* Device (really: libgomp plugin) to use for paged-locked memory. We
assume there is either none or exactly one such device for the lifetime of
the process. */
@@ -5929,6 +5969,8 @@ gomp_load_plugin_for_device (struct gomp_device_descr *device,
DLSYM (unload_image);
DLSYM (alloc);
DLSYM (free);
+ DLSYM_OPT (managed_alloc, managed_alloc);
+ DLSYM_OPT (managed_free, managed_free);
DLSYM_OPT (page_locked_host_alloc, page_locked_host_alloc);
DLSYM_OPT (page_locked_host_free, page_locked_host_free);
DLSYM (dev2host);
diff --git a/libgomp/testsuite/lib/libgomp.exp b/libgomp/testsuite/lib/libgomp.exp
index fd475ac3fe6..ba55cd39e2b 100644
--- a/libgomp/testsuite/lib/libgomp.exp
+++ b/libgomp/testsuite/lib/libgomp.exp
@@ -722,3 +722,12 @@ int main() {
return 0;
} } "-lhipblas" ]
}
+
+# return 1 if OpenMP Device Managed Memory is supported
+
+proc check_effective_target_omp_managedmem { } {
+ if { [check_effective_target_offload_device_nvptx] } {
+ return 1
+ }
+ return 0
+}
diff --git a/libgomp/testsuite/libgomp.c++/alloc-managed-1.C b/libgomp/testsuite/libgomp.c++/alloc-managed-1.C
new file mode 100644
index 00000000000..afd7fd648c6
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c++/alloc-managed-1.C
@@ -0,0 +1,35 @@
+// { dg-do run }
+// { dg-require-effective-target omp_managedmem }
+
+// Check that the ompx::allocator::gnu_managed_mem allocator can allocate
+// Managed Memory, and that host and target can see the data, at the same
+// address, without a mapping.
+
+#include <omp.h>
+#include <cstdint>
+#include <memory>
+
+int
+main ()
+{
+ using Allocator = ompx::allocator::gnu_managed_mem<int>;
+ using Traits = std::allocator_traits<Allocator>;
+
+ Allocator alloc;
+ int *a = Traits::allocate (alloc, 1);
+ if (!a)
+ __builtin_abort ();
+
+ Traits::construct (alloc, a, 42);
+ std::uintptr_t a_p = reinterpret_cast<std::uintptr_t>(a);
+
+ #pragma omp target is_device_ptr(a)
+ {
+ if (*a != 42 || a_p != reinterpret_cast<std::uintptr_t>(a))
+ __builtin_abort ();
+ }
+
+ Traits::destroy (alloc, a);
+ Traits::deallocate (alloc, a, 1);
+ return 0;
+}
diff --git a/libgomp/testsuite/libgomp.c/alloc-managed-1.c b/libgomp/testsuite/libgomp.c/alloc-managed-1.c
new file mode 100644
index 00000000000..31b252fc0ae
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-managed-1.c
@@ -0,0 +1,28 @@
+/* { dg-do run } */
+/* { dg-require-effective-target omp_managedmem } */
+
+/* Check that omp_alloc can allocate Managed Memory, and that host and target
+ can see the data, at the same address, without a mapping. */
+
+#include <omp.h>
+#include <stdint.h>
+
+int
+main ()
+{
+ int *a = (int *) omp_alloc(sizeof(int), ompx_gnu_managed_mem_alloc);
+ if (!a)
+ __builtin_abort ();
+
+ *a = 42;
+ uintptr_t a_p = (uintptr_t)a;
+
+ #pragma omp target is_device_ptr(a)
+ {
+ if (*a != 42 || a_p != (uintptr_t)a)
+ __builtin_abort ();
+ }
+
+ omp_free(a, ompx_gnu_managed_mem_alloc);
+ return 0;
+}
diff --git a/libgomp/testsuite/libgomp.c/alloc-managed-2.c b/libgomp/testsuite/libgomp.c/alloc-managed-2.c
new file mode 100644
index 00000000000..f7fd30a4f67
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-managed-2.c
@@ -0,0 +1,38 @@
+/* { dg-do run } */
+/* { dg-require-effective-target omp_managedmem } */
+
+/* Check that omp_calloc can allocate Managed Memory, and that host and target
+ can see the data, at the same address, without a mapping. */
+
+#include <omp.h>
+#include <stdint.h>
+
+int
+main ()
+{
+ int *a = (int *) omp_calloc(5, sizeof(int), ompx_gnu_managed_mem_alloc);
+ if (!a)
+ __builtin_abort ();
+
+ /* Check that memory is zero-initialized */
+ for (int i = 0; i < 5; i++)
+ if (a[i] != 0)
+ __builtin_abort ();
+
+ a[0] = 42;
+ a[4] = 99;
+ uintptr_t a_p = (uintptr_t)a;
+
+ #pragma omp target is_device_ptr(a)
+ {
+ if (a[0] != 42 || a[4] != 99 || a_p != (uintptr_t)a)
+ __builtin_abort ();
+ /* Check zero-initialization on device side */
+ for (int i = 1; i < 4; i++)
+ if (a[i] != 0)
+ __builtin_abort ();
+ }
+
+ omp_free(a, ompx_gnu_managed_mem_alloc);
+ return 0;
+}
diff --git a/libgomp/testsuite/libgomp.c/alloc-managed-3.c b/libgomp/testsuite/libgomp.c/alloc-managed-3.c
new file mode 100644
index 00000000000..17828b76962
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-managed-3.c
@@ -0,0 +1,44 @@
+/* { dg-do run } */
+/* { dg-require-effective-target omp_managedmem } */
+
+/* Check that omp_realloc can allocate Managed Memory, and that host and target
+ can see the data, at the same address, without a mapping. */
+
+#include <omp.h>
+#include <stdint.h>
+
+int
+main ()
+{
+ int *a = (int *) omp_alloc(2 * sizeof(int), ompx_gnu_managed_mem_alloc);
+ if (!a)
+ __builtin_abort ();
+
+ a[0] = 42;
+ a[1] = 43;
+
+ /* Reallocate to larger size */
+ int *b = (int *) omp_realloc(a, 5 * sizeof(int), ompx_gnu_managed_mem_alloc,
+ ompx_gnu_managed_mem_alloc);
+ if (!b)
+ __builtin_abort ();
+
+ /* Check that original data is preserved */
+ if (b[0] != 42 || b[1] != 43)
+ __builtin_abort ();
+
+ b[2] = 44;
+ b[3] = 45;
+ b[4] = 46;
+ uintptr_t b_p = (uintptr_t)b;
+
+ #pragma omp target is_device_ptr(b)
+ {
+ if (b[0] != 42 || b[1] != 43 || b[2] != 44 || b[3] != 45 || b[4] != 46
+ || b_p != (uintptr_t)b)
+ __builtin_abort ();
+ }
+
+ omp_free(b, ompx_gnu_managed_mem_alloc);
+ return 0;
+}
diff --git a/libgomp/testsuite/libgomp.c/alloc-managed-4.c b/libgomp/testsuite/libgomp.c/alloc-managed-4.c
new file mode 100644
index 00000000000..4eaf8259b6f
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/alloc-managed-4.c
@@ -0,0 +1,22 @@
+/* { dg-do run } */
+/* { dg-require-effective-target omp_managedmem } */
+/* { dg-shouldfail "" } */
+/* { dg-output "libgomp: attempted to free managed memory at 0x\[0-9a-f\]+, but the default device is set to the host device" } */
+
+/* Check that omp_free emits an error if the default device has been changed
+ to the host device. */
+
+#include <omp.h>
+#include <stdint.h>
+
+int
+main ()
+{
+ int *a = (int *) omp_alloc(2 * sizeof(int), ompx_gnu_managed_mem_alloc);
+ if (!a)
+ __builtin_abort ();
+
+ omp_set_default_device (omp_initial_device);
+ omp_free(a, ompx_gnu_managed_mem_alloc);
+ return 0;
+}
diff --git a/libgomp/testsuite/libgomp.fortran/alloc-managed-1.f90 b/libgomp/testsuite/libgomp.fortran/alloc-managed-1.f90
new file mode 100644
index 00000000000..685aeef7dae
--- /dev/null
+++ b/libgomp/testsuite/libgomp.fortran/alloc-managed-1.f90
@@ -0,0 +1,29 @@
+! { dg-do run }
+! { dg-require-effective-target omp_managedmem }
+
+! Check that omp_alloc can allocate Managed Memory, and that host and target
+! can see the data, at the same address, without a mapping.
+
+program main
+ use omp_lib
+ use iso_c_binding
+ implicit none
+
+ type(c_ptr) :: cptr
+ integer, pointer :: a
+ integer(c_intptr_t) :: a_p, a_p2
+
+ cptr = omp_alloc(c_sizeof(a), ompx_gnu_managed_mem_alloc)
+ if (.not. c_associated(cptr)) stop 1
+
+ call c_f_pointer(cptr, a)
+ a = 42
+ a_p = transfer(c_loc(a), a_p)
+
+ !$omp target is_device_ptr(a)
+ a_p2 = transfer(c_loc(a), a_p2)
+ if (a /= 42 .or. a_p /= a_p2) stop 2
+ !$omp end target
+
+ call omp_free(cptr, ompx_gnu_managed_mem_alloc)
+end program main
--
2.51.0
