https://gcc.gnu.org/g:ec03b6cec89e125eb5c955ca7180f06910f3527d
commit ec03b6cec89e125eb5c955ca7180f06910f3527d
Author: Thomas Schwinge <tho...@codesourcery.com>
Date: Fri Mar 24 15:14:57 2023 +0100
libgomp: Document OpenMP 'pinned' memory
libgomp/
* libgomp.texi (AMD Radeon, nvptx): Document OpenMP 'pinned'
memory.
Diff:
---
libgomp/ChangeLog.omp | 5 +++++
libgomp/libgomp.texi | 8 ++++++++
2 files changed, 13 insertions(+)
diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index 1b8f3dbaaf2..afb7dd62bc1 100644
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,8 @@
+2023-04-03 Thomas Schwinge <tho...@codesourcery.com>
+
+ * libgomp.texi (AMD Radeon, nvptx): Document OpenMP 'pinned'
+ memory.
+
2024-06-06 Jakub Jelinek <ja...@redhat.com>
* libgomp.texi (OpenMP 5.1 status): Mark Loop transformation constructs
diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi
index 526e936ef52..bc105464208 100644
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
@@ -6357,6 +6357,9 @@ The implementation remark:
@item OpenMP code that has a @code{requires} directive with
@code{unified_shared_memory} will remove any GCN device from the list of
available devices (``host fallback'').
+@item OpenMP @emph{pinned} memory (@code{omp_atk_pinned},
+ @code{ompx_pinned_mem_alloc}, for example)
+ is allocated via @code{mmap}, @code{mlock}.
@item The available stack size can be changed using the @code{GCN_STACK_SIZE}
environment variable; the default is 32 kiB per thread.
@item Low-latency memory (@code{omp_low_lat_mem_space}) is supported when the
@@ -6434,6 +6437,11 @@ The implementation remark:
@item OpenMP code that has a @code{requires} directive with
@code{unified_shared_memory} will remove any nvptx device from the
list of available devices (``host fallback'').
+@item OpenMP @emph{pinned} memory (@code{omp_atk_pinned},
+ @code{ompx_pinned_mem_alloc}, for example)
+ is allocated via @code{cuMemHostAlloc} (CUDA Driver API).
+ This potentially helps optimization of host <-> device data
+ transfers.
@item The default per-warp stack size is 128 kiB; see also @code{-msoft-stack}
in the GCC manual.
@item The OpenMP routines @code{omp_target_memcpy_rect} and
