| Message ID | 20140317135545.GM1850@spoyarek.pnq.redhat.com |
|---|---|
| State | New |
| Headers | show |
On 17-03-2014 10:55, Siddhesh Poyarekar wrote: > Hi, > > We got rid of LinuxThreads in 2005, but we didn't remove > __LT_SPINLOCK_INIT back then. Do it now. > > Siddhesh > > * nptl/sysdeps/pthread/bits/libc-lockP.h [defined NOT_IN_libc > && !defined IS_IN_libpthread && __LT_SPINNOCK_INIT != 0]: > Remove. > > diff --git a/nptl/sysdeps/pthread/bits/libc-lockP.h b/nptl/sysdeps/pthread/bits/libc-lockP.h > index bacc678..ec20271 100644 > --- a/nptl/sysdeps/pthread/bits/libc-lockP.h > +++ b/nptl/sysdeps/pthread/bits/libc-lockP.h > @@ -78,13 +78,8 @@ typedef pthread_key_t __libc_key_t; > CLASS __libc_lock_t NAME = LLL_LOCK_INITIALIZER; > # endif > #else > -# if __LT_SPINLOCK_INIT == 0 > -# define __libc_lock_define_initialized(CLASS,NAME) \ > +# define __libc_lock_define_initialized(CLASS,NAME) \ > CLASS __libc_lock_t NAME; > -# else > -# define __libc_lock_define_initialized(CLASS,NAME) \ > - CLASS __libc_lock_t NAME = PTHREAD_MUTEX_INITIALIZER; > -# endif > #endif > > #define __libc_rwlock_define_initialized(CLASS,NAME) \ I'm ok with this patch (In fact I was about to send this patch too).
On 17 March 2014 13:55, Siddhesh Poyarekar <siddhesh@redhat.com> wrote: Hi Siddesh, > We got rid of LinuxThreads in 2005, but we didn't remove > __LT_SPINLOCK_INIT back then. Do it now. This looks straightforward, however it seems the only arch that ever set __LT_SPINLOCK_INIT was hppa, so I assume this conditional was meant once upon a time to do something for hppa. I guess the patch is fine (as it does not change existing behaviour) but maybe someone who cares about hppa should verify that something isn't needed for that arch here.
On 17-03-2014 12:18, Will Newton wrote: > On 17 March 2014 13:55, Siddhesh Poyarekar <siddhesh@redhat.com> wrote: > > Hi Siddesh, > >> We got rid of LinuxThreads in 2005, but we didn't remove >> __LT_SPINLOCK_INIT back then. Do it now. > This looks straightforward, however it seems the only arch that ever > set __LT_SPINLOCK_INIT was hppa, so I assume this conditional was > meant once upon a time to do something for hppa. I guess the patch is > fine (as it does not change existing behaviour) but maybe someone who > cares about hppa should verify that something isn't needed for that > arch here. > Carlos O'Donnel is the maintainer for hppa. However, if you ever check on GLIBC (a simple grep), you will see __LT_SPINLOCK_INIT is never defined in any arch config file and it was only defined by when glibc used linuxpthread. So I think it safe to just get rid of it.
On Mon, Mar 17, 2014 at 12:31:18PM -0300, Adhemerval Zanella wrote: > Carlos O'Donnel is the maintainer for hppa. However, if you ever check on > GLIBC (a simple grep), you will see __LT_SPINLOCK_INIT is never defined in > any arch config file and it was only defined by when glibc used linuxpthread. > So I think it safe to just get rid of it. That's what I did, in addition to trying to figure out when it got added in, which led me to the hppa bits too. Siddhesh
On 03/17/2014 11:39 AM, Siddhesh Poyarekar wrote: > On Mon, Mar 17, 2014 at 12:31:18PM -0300, Adhemerval Zanella wrote: >> Carlos O'Donnel is the maintainer for hppa. However, if you ever check on >> GLIBC (a simple grep), you will see __LT_SPINLOCK_INIT is never defined in >> any arch config file and it was only defined by when glibc used linuxpthread. >> So I think it safe to just get rid of it. > > That's what I did, in addition to trying to figure out when it got > added in, which led me to the hppa bits too. The hppa port no longer needs __LT_SPINLOCK_INIT. As of NPTL we switched to zero-initialized locks to avoid the terrible headache of teaching developers that calloc() is not the right way to initialize a mutex, despite it working on x86*. We used to have one-initialized locks because hppa's only atomic operation is load-and-clear-word, and because of that we had our own special initialization in LinuxThreads. Cheers, Carlos.
diff --git a/nptl/sysdeps/pthread/bits/libc-lockP.h b/nptl/sysdeps/pthread/bits/libc-lockP.h index bacc678..ec20271 100644 --- a/nptl/sysdeps/pthread/bits/libc-lockP.h +++ b/nptl/sysdeps/pthread/bits/libc-lockP.h @@ -78,13 +78,8 @@ typedef pthread_key_t __libc_key_t; CLASS __libc_lock_t NAME = LLL_LOCK_INITIALIZER; # endif #else -# if __LT_SPINLOCK_INIT == 0 -# define __libc_lock_define_initialized(CLASS,NAME) \ +# define __libc_lock_define_initialized(CLASS,NAME) \ CLASS __libc_lock_t NAME; -# else -# define __libc_lock_define_initialized(CLASS,NAME) \ - CLASS __libc_lock_t NAME = PTHREAD_MUTEX_INITIALIZER; -# endif #endif #define __libc_rwlock_define_initialized(CLASS,NAME) \