Refactor internal-signals.h

The main drive is to optimize the internal usage and required size
when sigset_t is embedded in other data structures.  On Linux, the
current supported signal set requires up to 8 bytes (16 on mips),
was lower than the user defined sigset_t (128 bytes).

A new internal type internal_sigset_t is added, along with the
functions to operate on it similar to the ones for sigset_t.  The
internal-signals.h is also refactored to remove unused functions

Besides small stack usage on some functions (posix_spawn, abort)
it lower the struct pthread by about 120 bytes (112 on mips).

Checked on x86_64-linux-gnu.

Reviewed-by: Arjun Shankar <arjun@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/nptl/descr.h b/nptl/descr.h
index b5852632e3..5cacb286f3 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -35,6 +35,7 @@
 #include <kernel-features.h>
 #include <tls-internal-struct.h>
 #include <sys/rseq.h>
+#include <internal-sigset.h>
 
 #ifndef TCB_ALIGNMENT
 # define TCB_ALIGNMENT 32
@@ -387,7 +388,7 @@ struct pthread
   /* Signal mask for the new thread.  Used during thread startup to
      restore the signal mask.  (Threads are launched with all signals
      masked.)  */
-  sigset_t sigmask;
+  internal_sigset_t sigmask;
 
   /* Indicates whether is a C11 thread created by thrd_creat.  */
   bool c11;