glibc/sysdeps
Stefan Liebler dd037fb3df S390: Optimize lock-elision by decrementing adapt_count at unlock.
This patch decrements the adapt_count while unlocking the futex
instead of before aquiring the futex as it is done on power, too.
Furthermore a transaction is only started if the futex is currently free.
This check is done after starting the transaction, too.
If the futex is not free and the transaction nesting depth is one,
we can simply end the started transaction instead of aborting it.
The implementation of this check was faulty as it always ended the
started transaction.  By using the fallback path, the the outermost
transaction was aborted.  Now the outermost transaction is aborted
directly.

This patch also adds some commentary and aligns the code in
elision-trylock.c to the code in elision-lock.c as possible.

ChangeLog:

	* sysdeps/unix/sysv/linux/s390/lowlevellock.h
	(__lll_unlock_elision, lll_unlock_elision): Add adapt_count argument.
	* sysdeps/unix/sysv/linux/s390/elision-lock.c:
	(__lll_lock_elision): Decrement adapt_count while unlocking
	instead of before locking.
	* sysdeps/unix/sysv/linux/s390/elision-trylock.c
	(__lll_trylock_elision): Likewise.
	* sysdeps/unix/sysv/linux/s390/elision-unlock.c:
	(__lll_unlock_elision): Likewise.
2016-12-20 15:12:48 +01:00
..
aarch64 Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
alpha Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
arm New string function explicit_bzero (from OpenBSD). 2016-12-16 16:21:54 -05:00
generic ld.so: Remove __libc_memalign 2016-11-30 16:23:58 +01:00
gnu Define wordsize.h macros everywhere 2016-11-04 09:37:44 -07:00
hppa Add missing hidden_def (__sigsetjmp). 2016-12-01 20:49:25 +00:00
i386 Fix x86, x86_64 fmax, fmin sNaN handling, add tests (bug 20947). 2016-12-15 23:52:18 +00:00
ia64 Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
ieee754 Add fmaxmag, fminmag functions. 2016-12-20 00:46:53 +00:00
init_array Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
m68k Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
mach Fix hurd __access_noerrno implementation. 2016-11-18 16:49:08 -02:00
microblaze Remove cached PID/TID in clone 2016-11-24 19:38:51 -02:00
mips Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
nacl Add fmaxmag, fminmag functions. 2016-12-20 00:46:53 +00:00
nios2 Remove cached PID/TID in clone 2016-11-24 19:38:51 -02:00
nptl Remove cached PID/TID in clone 2016-11-24 19:38:51 -02:00
posix hurd: fix fcntl visibility 2016-09-18 23:48:55 +02:00
powerpc Fix powerpc64/power7 memchr for large input sizes 2016-12-16 11:30:20 -02:00
pthread Installed-header hygiene (BZ#20366): time.h types. 2016-09-23 08:43:56 -04:00
s390 Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
sh Add missing hidden_def (__sigsetjmp). 2016-12-01 20:49:25 +00:00
sparc Refactor long double information into bits/long-double.h. 2016-12-14 18:27:56 +00:00
tile Add missing hidden_def (__sigsetjmp). 2016-12-01 20:49:25 +00:00
unix S390: Optimize lock-elision by decrementing adapt_count at unlock. 2016-12-20 15:12:48 +01:00
wordsize-32 Define wordsize.h macros everywhere 2016-11-04 09:37:44 -07:00
wordsize-64 Define wordsize.h macros everywhere 2016-11-04 09:37:44 -07:00
x86 Disable TSX on some Haswell processors. 2016-12-19 14:15:57 +03:00
x86_64 Fix x86, x86_64 fmax, fmin sNaN handling, add tests (bug 20947). 2016-12-15 23:52:18 +00:00