linux-generic: Make cpu detection work with NO_HZ_FULL

sched_getaffinity() and pthread_getaffinity_np() do not return
an accurate mask of all CPUs in the machine when the kernel
is compiled with NO_HZ_FULL support.

See Linaro BUG 2027 for details.
	https://bugs.linaro.org/show_bug.cgi?id=2027

This code replaces the 'getaffinity' based CPU discovery logic
-and- removes any exclusivity between default control and worker
cpumasks, based on an assumption that external cpumask specifications
will segregate CPUs if needed.

The results of these changes which address BUG 2027 are:
(1) all CPUs known to the kernel at boot time are considered
    for use by ODP regardless of the default CPU affinity masks
    set by the kernel scheduler,
(2) the default control and worker cpumasks are given reasonable
    values based on the set of installed CPUs

Also - this code:
(a) adds control and worker cpumasks to the linux-generic global data
(b) adds logic to odp_cpumask.c to initialize these masks
(c) calls the new cpumask initialization logic from odp_init_global()
(d) reduces odp_cpumask_default_control() and
    odp_cpumask_default_worker() to use the content of these new
    cpumasks without modification.
These changes provide prerequisite infrastructure for pending changes
which will allow ODP to accept cpumasks passed in
from external entities such as a provisioning service.

Signed-off-by: Gary S. Robertson <gary.robertson@linaro.org>
Signed-off-by: Bill Fischofer <bill.fischofer@linaro.org>
Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>

1 files changed, 14 insertions, 3 deletions

diff --git a/platform/linux-generic/odp_init.c b/platform/linux-generic/odp_init.c
index 284cecf05..56b1e9585 100644
--- a/platform/linux-generic/odp_init.c
+++ b/platform/linux-generic/odp_init.c
@@ -3,11 +3,9 @@
  *
  * SPDX-License-Identifier:     BSD-3-Clause
  */
-
 #include <odp/api/init.h>
-#include <odp_internal.h>
-#include <odp/api/debug.h>
 #include <odp_debug_internal.h>
+#include <odp/api/debug.h>
 #include <unistd.h>
 
 struct odp_global_data_s odp_global_data;
@@ -29,6 +27,12 @@ int odp_init_global(odp_instance_t *instance,
 			odp_global_data.abort_fn = params->abort_fn;
 	}
 
+	if (odp_cpumask_init_global()) {
+		ODP_ERR("ODP cpumask init failed.\n");
+		goto init_failed;
+	}
+	stage = CPUMASK_INIT;
+
 	if (odp_time_init_global()) {
 		ODP_ERR("ODP time init failed.\n");
 		goto init_failed;
@@ -222,6 +226,13 @@ int _odp_term_global(enum init_stage stage)
 		}
 		/* Fall through */
 
+	case CPUMASK_INIT:
+		if (odp_cpumask_term_global()) {
+			ODP_ERR("ODP cpumask term failed.\n");
+			rc = -1;
+		}
+		/* Fall through */
+
 	case NO_INIT:
 		;
 	}