You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
44 lines
1.1 KiB
44 lines
1.1 KiB
3 years ago
|
commit 1d350aa06091211863e41169729cee1bca39f72f
|
||
|
|
Author: Florian Weimer <fweimer@redhat.com>
|
||
|
|
Date: Thu Dec 9 09:49:32 2021 +0100
|
||
|
|
|
||
|
|
Linux: Use rseq to accelerate sched_getcpu
|
||
|
|
|
||
|
|
Co-Authored-By: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
|
||
|
|
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
|
||
|
|
|
||
|
|
diff --git a/sysdeps/unix/sysv/linux/sched_getcpu.c b/sysdeps/unix/sysv/linux/sched_getcpu.c
|
||
|
|
index c41e986f2cab5e42..6f78edaea1495342 100644
|
||
|
|
--- a/sysdeps/unix/sysv/linux/sched_getcpu.c
|
||
|
|
+++ b/sysdeps/unix/sysv/linux/sched_getcpu.c
|
||
|
|
@@ -20,8 +20,8 @@
|
||
|
|
#include <sysdep.h>
|
||
|
|
#include <sysdep-vdso.h>
|
||
|
|
|
||
|
|
-int
|
||
|
|
-sched_getcpu (void)
|
||
|
|
+static int
|
||
|
|
+vsyscall_sched_getcpu (void)
|
||
|
|
{
|
||
|
|
unsigned int cpu;
|
||
|
|
int r = -1;
|
||
|
|
@@ -32,3 +32,18 @@ sched_getcpu (void)
|
||
|
|
#endif
|
||
|
|
return r == -1 ? r : cpu;
|
||
|
|
}
|
||
|
|
+
|
||
|
|
+#ifdef RSEQ_SIG
|
||
|
|
+int
|
||
|
|
+sched_getcpu (void)
|
||
|
|
+{
|
||
|
|
+ int cpu_id = THREAD_GETMEM_VOLATILE (THREAD_SELF, rseq_area.cpu_id);
|
||
|
|
+ return __glibc_likely (cpu_id >= 0) ? cpu_id : vsyscall_sched_getcpu ();
|
||
|
|
+}
|
||
|
|
+#else /* RSEQ_SIG */
|
||
|
|
+int
|
||
|
|
+sched_getcpu (void)
|
||
|
|
+{
|
||
|
|
+ return vsyscall_sched_getcpu ();
|
||
|
|
+}
|
||
|
|
+#endif /* RSEQ_SIG */
|