libgomp: Ensure that either gomp_team is properly aligned [PR102838]

struct gomp_team has struct gomp_work_share array inside of it.
If that latter structure has 64-byte aligned member in the middle,
the whole struct gomp_team needs to be 64-byte aligned, but we weren't
allocating it using gomp_aligned_alloc.

This patch fixes that, except that on gcn team_malloc is special, so
I've instead decided at least for now to avoid using aligned member
and use the padding instead on gcn.

2021-11-18  Jakub Jelinek  <jakub@redhat.com>

	PR libgomp/102838
	* libgomp.h (GOMP_USE_ALIGNED_WORK_SHARES): Define if
	GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC is defined and __AMDGCN__ is not.
	(struct gomp_work_share): Use GOMP_USE_ALIGNED_WORK_SHARES instead of
	GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC.
	* work.c (alloc_work_share, gomp_work_share_start): Likewise.
	* team.c (gomp_new_team): If GOMP_USE_ALIGNED_WORK_SHARES, use
	gomp_aligned_alloc instead of team_malloc.
This commit is contained in:
Jakub Jelinek 2021-11-18 09:10:40 +01:00
parent 7a2aa63fad
commit 17da2c7425
3 changed files with 12 additions and 3 deletions

View File

@ -95,6 +95,10 @@ enum memmodel
#define GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC 1
#endif
#if defined(GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC) && !defined(__AMDGCN__)
#define GOMP_USE_ALIGNED_WORK_SHARES 1
#endif
extern void *gomp_malloc (size_t) __attribute__((malloc));
extern void *gomp_malloc_cleared (size_t) __attribute__((malloc));
extern void *gomp_realloc (void *, size_t);
@ -348,7 +352,7 @@ struct gomp_work_share
are in a different cache line. */
/* This lock protects the update of the following members. */
#ifdef GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC
#ifdef GOMP_USE_ALIGNED_WORK_SHARES
gomp_mutex_t lock __attribute__((aligned (64)));
#else
char pad[64 - offsetof (struct gomp_work_share_1st_cacheline, pad)];

View File

@ -177,7 +177,12 @@ gomp_new_team (unsigned nthreads)
{
size_t extra = sizeof (team->ordered_release[0])
+ sizeof (team->implicit_task[0]);
#ifdef GOMP_USE_ALIGNED_WORK_SHARES
team = gomp_aligned_alloc (__alignof (struct gomp_team),
sizeof (*team) + nthreads * extra);
#else
team = team_malloc (sizeof (*team) + nthreads * extra);
#endif
#ifndef HAVE_SYNC_BUILTINS
gomp_mutex_init (&team->work_share_list_free_lock);

View File

@ -78,7 +78,7 @@ alloc_work_share (struct gomp_team *team)
team->work_share_chunk *= 2;
/* Allocating gomp_work_share structures aligned is just an
optimization, don't do it when using the fallback method. */
#ifdef GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC
#ifdef GOMP_USE_ALIGNED_WORK_SHARES
ws = gomp_aligned_alloc (__alignof (struct gomp_work_share),
team->work_share_chunk
* sizeof (struct gomp_work_share));
@ -191,7 +191,7 @@ gomp_work_share_start (size_t ordered)
/* Work sharing constructs can be orphaned. */
if (team == NULL)
{
#ifdef GOMP_HAVE_EFFICIENT_ALIGNED_ALLOC
#ifdef GOMP_USE_ALIGNED_WORK_SHARES
ws = gomp_aligned_alloc (__alignof (struct gomp_work_share),
sizeof (*ws));
#else