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| author | Florian Weimer <fweimer@redhat.com> | 2021-05-10 10:31:41 +0200 |
|---|---|---|
| committer | Florian Weimer <fweimer@redhat.com> | 2021-05-10 10:31:41 +0200 |
| commit | 29d4d1be681fee2fa7cf23205b6d993a3b2a4566 (patch) | |
| tree | 323727f2eaec15bc660f8e17f4d7fe3413812d27 /sysdeps | |
| parent | 1c75f89613a0b2428c21c19598559a2d64221cde (diff) | |
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Linux: Simplify and fix the definition of SINGLE_THREAD_P
Always use __libc_multiple_threads if beneficial, and do not assume
the the dynamic loader is single-threaded. This assumption could
become incorrect by accident once more code is moved from libpthread
into it. The previous commit introducing the
NO_SYSCALL_CANCEL_CHECKING macro enables this change.
Do not hint to the compiler that multi-threaded programs are unlikely
(which is not quite true anymore).
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/unix/sysv/linux/single-thread.h | 36 |
1 files changed, 7 insertions, 29 deletions
diff --git a/sysdeps/unix/sysv/linux/single-thread.h b/sysdeps/unix/sysv/linux/single-thread.h index 841f8c69d5..2fac8dcc11 100644 --- a/sysdeps/unix/sysv/linux/single-thread.h +++ b/sysdeps/unix/sysv/linux/single-thread.h @@ -32,35 +32,13 @@ extern int __libc_multiple_threads; libc_hidden_proto (__libc_multiple_threads) #endif -#ifdef SINGLE_THREAD_BY_GLOBAL -# if IS_IN (libc) -# define SINGLE_THREAD_P \ - __glibc_likely (__libc_multiple_threads == 0) -# elif IS_IN (libpthread) -extern int __pthread_multiple_threads; -# define SINGLE_THREAD_P \ - __glibc_likely (__pthread_multiple_threads == 0) -# elif IS_IN (librt) -# define SINGLE_THREAD_P \ - __glibc_likely (THREAD_GETMEM (THREAD_SELF, \ - header.multiple_threads) == 0) -# else -/* For rtld, et cetera. */ -# define SINGLE_THREAD_P (1) -# endif -#else /* SINGLE_THREAD_BY_GLOBAL */ -# if IS_IN (libc) || IS_IN (libpthread) || IS_IN (librt) -# define SINGLE_THREAD_P \ - __glibc_likely (THREAD_GETMEM (THREAD_SELF, \ - header.multiple_threads) == 0) -# else -/* For rtld, et cetera. */ -# define SINGLE_THREAD_P (1) -# endif -#endif /* SINGLE_THREAD_BY_GLOBAL */ +#if !defined SINGLE_THREAD_BY_GLOBAL || IS_IN (rtld) +# define SINGLE_THREAD_P \ + (THREAD_GETMEM (THREAD_SELF, header.multiple_threads) == 0) +#else +# define SINGLE_THREAD_P (__libc_multiple_threads == 0) +#endif -#define RTLD_SINGLE_THREAD_P \ - __glibc_likely (THREAD_GETMEM (THREAD_SELF, \ - header.multiple_threads) == 0) +#define RTLD_SINGLE_THREAD_P SINGLE_THREAD_P #endif /* _SINGLE_THREAD_H */ |