diff options
author | Jakub Jelinek <jakub@redhat.com> | 2021-11-11 13:57:31 +0100 |
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committer | Jakub Jelinek <jakub@redhat.com> | 2021-11-11 13:57:31 +0100 |
commit | fa4fcb111ad4ef015c1caf7c4b5a60d35b3aa997 (patch) | |
tree | 47cf272646cfeb4696cf717425f5ddfb2de4c70d /libgomp/teams.c | |
parent | 3e5a19053310ad090b930fbecebceb28bd1b91a4 (diff) |
libgomp: Use TLS storage for omp_get_num_teams()/omp_get_team_num() values
When thinking about GOMP_teams3, I've realized that using global variables
for the values returned by omp_get_num_teams()/omp_get_team_num() calls
is incorrect even with our right now dumb way of implementing host teams.
The problems are two, one is if host teams is used from multiple pthread_create
created threads - the spec says that host teams can't be nested inside of
explicit parallel or other teams constructs, but with pthread_create the
standard says obviously nothing about it. Another more important thing
is host fallback, right now we don't do anything for omp_get_num_teams()
or omp_get_team_num() which was fine before host teams was introduced and
the 5.1 requirement that num_teams clause specifies minimum of teams, but
with the global vars it means inside of target teams num_teams (2) we happily
return omp_get_num_teams() == 4 if the target teams is inside of host teams
with num_teams(4). With target fallback being invoked from parallel
regions global vars simply can't work right on the host.
So, this patch moves them to struct gomp_thread and propagates those for
parallel to child threads. For host fallback, the implicit zeroing of
*thr results in us returning omp_get_num_teams () == 1 and
omp_get_team_num () == 0 which is fine for target teams without num_teams
clause, for target teams with num_teams clause something to work on and
for target without teams nested in it I've asked on omp-lang what should
be done.
2021-11-11 Jakub Jelinek <jakub@redhat.com>
* libgomp.h (struct gomp_thread): Add num_teams and team_num members.
* team.c (struct gomp_thread_start_data): Likewise.
(gomp_thread_start): Initialize thr->num_teams and thr->team_num.
(gomp_team_start): Initialize start_data->num_teams and
start_data->team_num. Update nthr->num_teams and nthr->team_num.
* teams.c (gomp_num_teams, gomp_team_num): Remove.
(GOMP_teams_reg): Set and restore thr->num_teams and thr->team_num
instead of gomp_num_teams and gomp_team_num.
(omp_get_num_teams): Use thr->num_teams + 1 instead of gomp_num_teams.
(omp_get_team_num): Use thr->team_num instead of gomp_team_num.
* testsuite/libgomp.c/teams-4.c: New test.
Diffstat (limited to 'libgomp/teams.c')
-rw-r--r-- | libgomp/teams.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/libgomp/teams.c b/libgomp/teams.c index 9409f8ee6aa..a93fb7cc6e1 100644 --- a/libgomp/teams.c +++ b/libgomp/teams.c @@ -28,14 +28,12 @@ #include "libgomp.h" #include <limits.h> -static unsigned gomp_num_teams = 1, gomp_team_num = 0; - void GOMP_teams_reg (void (*fn) (void *), void *data, unsigned int num_teams, unsigned int thread_limit, unsigned int flags) { + struct gomp_thread *thr = gomp_thread (); (void) flags; - (void) num_teams; unsigned old_thread_limit_var = 0; if (thread_limit == 0) thread_limit = gomp_teams_thread_limit_var; @@ -48,11 +46,11 @@ GOMP_teams_reg (void (*fn) (void *), void *data, unsigned int num_teams, } if (num_teams == 0) num_teams = gomp_nteams_var ? gomp_nteams_var : 3; - gomp_num_teams = num_teams; - for (gomp_team_num = 0; gomp_team_num < num_teams; gomp_team_num++) + thr->num_teams = num_teams - 1; + for (thr->team_num = 0; thr->team_num < num_teams; thr->team_num++) fn (data); - gomp_num_teams = 1; - gomp_team_num = 0; + thr->num_teams = 0; + thr->team_num = 0; if (thread_limit) { struct gomp_task_icv *icv = gomp_icv (true); @@ -63,13 +61,15 @@ GOMP_teams_reg (void (*fn) (void *), void *data, unsigned int num_teams, int omp_get_num_teams (void) { - return gomp_num_teams; + struct gomp_thread *thr = gomp_thread (); + return thr->num_teams + 1; } int omp_get_team_num (void) { - return gomp_team_num; + struct gomp_thread *thr = gomp_thread (); + return thr->team_num; } ialias (omp_get_num_teams) |