From 07ed18d26a342741cb25a4739158c65ed9dd4d09 Mon Sep 17 00:00:00 2001 From: Rogerio Alves Date: Tue, 5 Dec 2017 14:24:14 -0200 Subject: Add elision tunables This patch adds several new tunables to control the behavior of elision on supported platforms[1]. Since elision now depends on tunables, we should always *compile* with elision enabled, and leave the code disabled, but available for runtime selection. This gives us *much* better compile-time testing of the existing code to avoid bit-rot[2]. Tested on ppc, ppc64, ppc64le, s390x and x86_64. [1] This part of the patch was initially proposed by Paul Murphy but was "staled" because the framework have changed since the patch was originally proposed: https://patchwork.sourceware.org/patch/10342/ [2] This part of the patch was inititally proposed as a RFC by Carlos O'Donnell. Make sense to me integrate this on the patch: https://sourceware.org/ml/libc-alpha/2017-05/msg00335.html * elf/dl-tunables.list: Add elision parameters. * manual/tunables.texi: Add entries about elision tunable. * sysdeps/unix/sysv/linux/powerpc/elision-conf.c: Add callback functions to dynamically enable/disable elision. Add multiple callbacks functions to set elision parameters. Deleted __libc_enable_secure check. * sysdeps/unix/sysv/linux/s390/elision-conf.c: Likewise. * sysdeps/unix/sysv/linux/x86/elision-conf.c: Likewise. * configure: Regenerated. * configure.ac: Option enable_lock_elision was deleted. * config.h.in: ENABLE_LOCK_ELISION flag was deleted. * config.make.in: Remove references to enable_lock_elision. * manual/install.texi: Elision configure option was removed. * INSTALL: Regenerated to remove enable_lock_elision. * nptl/Makefile: Disable elision so it can verify error case for destroying a mutex. * sysdeps/powerpc/nptl/elide.h: Cleanup ENABLE_LOCK_ELISION check. Deleted macros for the case when ENABLE_LOCK_ELISION was not defined. * sysdeps/s390/configure: Regenerated. * sysdeps/s390/configure.ac: Remove references to enable_lock_elision.. * nptl/tst-mutex8.c: Deleted all #ifndef ENABLE_LOCK_ELISION from the test. * sysdeps/powerpc/powerpc32/sysdep.h: Deleted all ENABLE_LOCK_ELISION checks. * sysdeps/powerpc/powerpc64/sysdep.h: Likewise. * sysdeps/powerpc/sysdep.h: Likewise. * sysdeps/s390/nptl/bits/pthreadtypes-arch.h: Likewise. * sysdeps/unix/sysv/linux/powerpc/force-elision.h: Likewise. * sysdeps/unix/sysv/linux/s390/elision-conf.h: Likewise. * sysdeps/unix/sysv/linux/s390/force-elision.h: Likewise. * sysdeps/unix/sysv/linux/s390/lowlevellock.h: Likewise. * sysdeps/unix/sysv/linux/s390/Makefile: Remove references to enable-lock-elision. Reviewed-by: Tulio Magno Quites Machado Filho --- elf/dl-tunables.list | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'elf') diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list index c188c6ad52..ec0fe20787 100644 --- a/elf/dl-tunables.list +++ b/elf/dl-tunables.list @@ -96,4 +96,38 @@ glibc { default: HWCAP_IMPORTANT } } + + elision { + enable { + type: INT_32 + minval: 0 + maxval: 1 + security_level: SXID_ERASE + } + skip_lock_busy { + type: INT_32 + default: 3 + security_level: SXID_ERASE + } + skip_lock_internal_abort { + type: INT_32 + default: 3 + security_level: SXID_ERASE + } + skip_lock_after_retries { + type: INT_32 + default: 3 + security_level: SXID_ERASE + } + tries { + type: INT_32 + default: 3 + security_level: SXID_ERASE + } + skip_trylock_internal_abort { + type: INT_32 + default: 3 + security_level: SXID_ERASE + } + } } -- cgit v1.2.3