diff mbox series

[v2,1/3] misc: Add __get_nprocs_sched

Message ID 20210907122259.79800-2-adhemerval.zanella@linaro.org
State New
Headers show
Series Revert the use of sched_getaffinity on get_nproc | expand

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Adhemerval Zanella Sept. 7, 2021, 12:22 p.m. UTC
This is an internal function meant to return the number of avaliable
processor where the process can scheduled, different than the
__get_nprocs which returns a the system available online CPU.

The Linux implementation currently only calls __get_nprocs(), which
in tuns calls sched_getaffinity.
---
 include/sys/sysinfo.h                 | 7 ++++++-
 malloc/arena.c                        | 2 +-
 misc/getsysstats.c                    | 6 ++++++
 sysdeps/mach/getsysstats.c            | 6 ++++++
 sysdeps/unix/sysv/linux/getsysstats.c | 6 ++++++
 5 files changed, 25 insertions(+), 2 deletions(-)

Comments

Florian Weimer Sept. 13, 2021, 11:05 a.m. UTC | #1
* Adhemerval Zanella:

> This is an internal function meant to return the number of avaliable
> processor where the process can scheduled, different than the
> __get_nprocs which returns a the system available online CPU.
>
> The Linux implementation currently only calls __get_nprocs(), which
> in tuns calls sched_getaffinity.

Looks okay to me.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Thanks,
Florian
diff mbox series

Patch

diff --git a/include/sys/sysinfo.h b/include/sys/sysinfo.h
index 7388356a19..c490561581 100644
--- a/include/sys/sysinfo.h
+++ b/include/sys/sysinfo.h
@@ -9,10 +9,15 @@ 
 extern int __get_nprocs_conf (void);
 libc_hidden_proto (__get_nprocs_conf)
 
-/* Return number of available processors.  */
+/* Return number of available processors (not all of them will be
+   available to the caller process).  */
 extern int __get_nprocs (void);
 libc_hidden_proto (__get_nprocs)
 
+/* Return the number of available processors which the process can
+   be scheduled.  */
+extern int __get_nprocs_sched (void) attribute_hidden;
+
 /* Return number of physical pages of memory in the system.  */
 extern long int __get_phys_pages (void);
 libc_hidden_proto (__get_phys_pages)
diff --git a/malloc/arena.c b/malloc/arena.c
index 4c398753ae..78ef4cf18c 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -878,7 +878,7 @@  arena_get2 (size_t size, mstate avoid_arena)
             narenas_limit = mp_.arena_max;
           else if (narenas > mp_.arena_test)
             {
-              int n = __get_nprocs ();
+              int n = __get_nprocs_sched ();
 
               if (n >= 1)
                 narenas_limit = NARENAS_FROM_NCORES (n);
diff --git a/misc/getsysstats.c b/misc/getsysstats.c
index 2986d62247..5cbba0f9bd 100644
--- a/misc/getsysstats.c
+++ b/misc/getsysstats.c
@@ -44,6 +44,12 @@  weak_alias (__get_nprocs, get_nprocs)
 link_warning (get_nprocs, "warning: get_nprocs will always return 1")
 
 
+int
+__get_nprocs_sched (void)
+{
+  return 1;
+}
+
 long int
 __get_phys_pages (void)
 {
diff --git a/sysdeps/mach/getsysstats.c b/sysdeps/mach/getsysstats.c
index 1267f39da2..cc8023f979 100644
--- a/sysdeps/mach/getsysstats.c
+++ b/sysdeps/mach/getsysstats.c
@@ -62,6 +62,12 @@  __get_nprocs (void)
 libc_hidden_def (__get_nprocs)
 weak_alias (__get_nprocs, get_nprocs)
 
+int
+__get_nprocs_sched (void)
+{
+  return __get_nprocs ();
+}
+
 /* Return the number of physical pages on the system. */
 long int
 __get_phys_pages (void)
diff --git a/sysdeps/unix/sysv/linux/getsysstats.c b/sysdeps/unix/sysv/linux/getsysstats.c
index 8a5d342f0c..e9c0dc4d83 100644
--- a/sysdeps/unix/sysv/linux/getsysstats.c
+++ b/sysdeps/unix/sysv/linux/getsysstats.c
@@ -87,6 +87,12 @@  __get_nprocs (void)
 libc_hidden_def (__get_nprocs)
 weak_alias (__get_nprocs, get_nprocs)
 
+int
+__get_nprocs_sched (void)
+{
+  return __get_nprocs ();
+}
+
 
 /* On some architectures it is possible to distinguish between configured
    and active cpus.  */