From: Andrew Stubbs Date: Fri, 11 Mar 2022 14:33:11 +0000 (+0000) Subject: openmp, nvptx: low-lat memory access traits X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ef3c1a66eec978a1e20e29aaab8af2772560efcd;p=thirdparty%2Fgcc.git 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 --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp index 6f7004bcc4b6..afec85d0829a 100644 --- a/libgomp/ChangeLog.omp +++ b/libgomp/ChangeLog.omp @@ -1,3 +1,18 @@ +2022-03-11 Andrew Stubbs + + 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 Backport of a patch posted at diff --git a/libgomp/allocator.c b/libgomp/allocator.c index a84b36a99425..5889e26b798f 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 f740b97f6aca..0102680b7170 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 9fa6aa1624f3..83a60933c214 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 90bf73095ef5..9c22466fbd66 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 000000000000..a0a738b1d1d6 --- /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 +#include + +#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; +} +