Message ID | Pine.LNX.4.64.1403252334530.10779@digraph.polyomino.org.uk |
---|---|
State | New |
Headers | show |
From: "Joseph S. Myers" <joseph@codesourcery.com> Date: Tue, 25 Mar 2014 23:36:36 +0000 > On Tue, 25 Mar 2014, David Miller wrote: > >> From: "Joseph S. Myers" <joseph@codesourcery.com> >> Date: Tue, 25 Mar 2014 23:20:00 +0000 >> >> > On Tue, 25 Mar 2014, David Miller wrote: >> > >> >> Actually, it turns out you can simply test for the CPP macro __sparc_v9__ >> > >> > In that case, here is a revised patch using __sparc_v9__ in place of >> > __arch64__. >> >> It only get's set for 32-bit v9, you'll need to keep the >> (__sparc__ && __arch64__) in an "||" conditional branch. >> >> Something like (__sparc__ && (__arch64__ || __sparc_v9__)) > > Here's a third patch version. Looks good to me.
> -----Original Message----- > From: David Miller [mailto:davem@davemloft.net] > Sent: Wednesday, 26 March 2014 10:21 am > To: joseph@codesourcery.com > Cc: libc-alpha@sourceware.org; schwab@linux-m68k.org; David Holsgrove; > aurel32@debian.org > Subject: Re: Correct robust mutex / PI futex kernel assumptions (bug 9894) > > From: "Joseph S. Myers" <joseph@codesourcery.com> > Date: Tue, 25 Mar 2014 23:36:36 +0000 > > > On Tue, 25 Mar 2014, David Miller wrote: > > > >> From: "Joseph S. Myers" <joseph@codesourcery.com> > >> Date: Tue, 25 Mar 2014 23:20:00 +0000 > >> > >> > On Tue, 25 Mar 2014, David Miller wrote: > >> > > >> >> Actually, it turns out you can simply test for the CPP macro __sparc_v9__ > >> > > >> > In that case, here is a revised patch using __sparc_v9__ in place of > >> > __arch64__. > >> > >> It only get's set for 32-bit v9, you'll need to keep the > >> (__sparc__ && __arch64__) in an "||" conditional branch. > >> > >> Something like (__sparc__ && (__arch64__ || __sparc_v9__)) > > > > Here's a third patch version. > > Looks good to me. Good for MicroBlaze too - thanks Joseph, David
diff --git a/sysdeps/unix/sysv/linux/arm/kernel-features.h b/sysdeps/unix/sysv/linux/arm/kernel-features.h index 401343b..96b7350 100644 --- a/sysdeps/unix/sysv/linux/arm/kernel-features.h +++ b/sysdeps/unix/sysv/linux/arm/kernel-features.h @@ -53,3 +53,10 @@ # undef __ASSUME_PSELECT # undef __ASSUME_PPOLL #endif + +/* The ARM kernel may or may not support + futex_atomic_cmpxchg_inatomic, depending on kernel + configuration. */ +#undef __ASSUME_FUTEX_LOCK_PI +#undef __ASSUME_REQUEUE_PI +#undef __ASSUME_SET_ROBUST_LIST diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 555b82c..db6af35 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -106,9 +106,12 @@ # define __ASSUME_ATFCTS 1 #endif -/* Support for inter-process robust mutexes was added in 2.6.17. */ +/* Support for inter-process robust mutexes was added in 2.6.17 (but + some architectures lack futex_atomic_cmpxchg_inatomic in some + configurations). */ #if __LINUX_KERNEL_VERSION >= 0x020611 \ - && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613) + && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613) \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_SET_ROBUST_LIST 1 #endif @@ -119,8 +122,10 @@ # define __ASSUME_COMPLETE_READV_WRITEV 1 #endif -/* Support for PI futexes was added in 2.6.18. */ -#if __LINUX_KERNEL_VERSION >= 0x020612 +/* Support for PI futexes was added in 2.6.18 (but some architectures + lack futex_atomic_cmpxchg_inatomic in some configurations). */ +#if __LINUX_KERNEL_VERSION >= 0x020612 \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_FUTEX_LOCK_PI 1 #endif @@ -223,8 +228,11 @@ # define __ASSUME_PWRITEV 1 #endif -/* Support for FUTEX_*_REQUEUE_PI was added in 2.6.31. */ -#if __LINUX_KERNEL_VERSION >= 0x02061f +/* Support for FUTEX_*_REQUEUE_PI was added in 2.6.31 (but some + architectures lack futex_atomic_cmpxchg_inatomic in some + configurations). */ +#if __LINUX_KERNEL_VERSION >= 0x02061f \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_REQUEUE_PI 1 #endif diff --git a/sysdeps/unix/sysv/linux/m68k/kernel-features.h b/sysdeps/unix/sysv/linux/m68k/kernel-features.h index cb8915f..bc340bd 100644 --- a/sysdeps/unix/sysv/linux/m68k/kernel-features.h +++ b/sysdeps/unix/sysv/linux/m68k/kernel-features.h @@ -48,6 +48,7 @@ /* No support for PI futexes or robust mutexes before 3.10 for m68k. */ #if __LINUX_KERNEL_VERSION < 0x030a00 +# undef __ASSUME_FUTEX_LOCK_PI # undef __ASSUME_REQUEUE_PI # undef __ASSUME_SET_ROBUST_LIST #endif diff --git a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h index f9a61a9..a62b839 100644 --- a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h +++ b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h @@ -43,6 +43,13 @@ #include_next <kernel-features.h> +/* Support for futex_atomic_cmpxchg_inatomic was added in 2.6.33. */ +#if __LINUX_KERNEL_VERSION < 0x020621 +# undef __ASSUME_FUTEX_LOCK_PI +# undef __ASSUME_REQUEUE_PI +# undef __ASSUME_SET_ROBUST_LIST +#endif + /* The MicroBlaze kernel does not support the pselect6, preadv and pwritev syscalls. */ #undef __ASSUME_PSELECT diff --git a/sysdeps/unix/sysv/linux/mips/kernel-features.h b/sysdeps/unix/sysv/linux/mips/kernel-features.h index 52cbf3a..19d3cba 100644 --- a/sysdeps/unix/sysv/linux/mips/kernel-features.h +++ b/sysdeps/unix/sysv/linux/mips/kernel-features.h @@ -53,3 +53,11 @@ #if _MIPS_SIM == _ABIN32 && __LINUX_KERNEL_VERSION < 0x020623 # undef __ASSUME_GETDENTS64_SYSCALL #endif + +/* The MIPS kernel does not support futex_atomic_cmpxchg_inatomic if + emulating LL/SC. */ +#if __mips == 1 || defined _MIPS_ARCH_R5900 +# undef __ASSUME_FUTEX_LOCK_PI +# undef __ASSUME_REQUEUE_PI +# undef __ASSUME_SET_ROBUST_LIST +#endif