Dear Community, > This is the helper function, which uses struct __timespec64 > to provide 64 bit absolute time to futex syscalls. > > The aim of this function is to move convoluted pre-processor > macro code from sysdeps/nptl/lowlevellock-futex.h to C > function in futex-internal.c > > The futex_abstimed_wait64 function has been put into a separate > file on the purpose - to avoid issues apparent on the m68k > architecture related to small number of available registers (there > is not enough registers to put all necessary arguments in them if > the above function would be added to futex-internal.h with > __always_inline attribute). > > Additional precautions for m68k port have been taken - the > futex-internal.c file will be compiled with -fno-inline flag. > Do we have more comments regarding this patch? Or shall I pull it to -master? > --- > Changes for v2: > - Handle the case when *abstime pointer is NULL > --- > sysdeps/nptl/futex-internal.c | 70 > +++++++++++++++++++++++++++ sysdeps/nptl/futex-internal.h | > 6 +++ sysdeps/unix/sysv/linux/m68k/Makefile | 2 + > 3 files changed, 78 insertions(+) > > diff --git a/sysdeps/nptl/futex-internal.c > b/sysdeps/nptl/futex-internal.c index 3366aac162..3211b4c94f 100644 > --- a/sysdeps/nptl/futex-internal.c > +++ b/sysdeps/nptl/futex-internal.c > @@ -45,6 +45,29 @@ __futex_abstimed_wait_cancelable32 (unsigned int* > futex_word, abstime != NULL ? &ts32 : NULL, > NULL /* Unused. */, > FUTEX_BITSET_MATCH_ANY); } > + > +static int > +__futex_abstimed_wait32 (unsigned int* futex_word, > + unsigned int expected, clockid_t clockid, > + const struct __timespec64* abstime, > + int private) > +{ > + struct timespec ts32; > + > + if (abstime != NULL && ! in_time_t_range (abstime->tv_sec)) > + return -EOVERFLOW; > + > + unsigned int clockbit = (clockid == CLOCK_REALTIME) ? > + FUTEX_CLOCK_REALTIME : 0; > + int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, > private); + > + if (abstime != NULL) > + ts32 = valid_timespec64_to_timespec (*abstime); > + > + return INTERNAL_SYSCALL_CALL (futex, futex_word, op, expected, > + abstime != NULL ? &ts32 : NULL, > + NULL /* Unused. */, > FUTEX_BITSET_MATCH_ANY); +} > #endif > > int > @@ -97,3 +120,50 @@ __futex_abstimed_wait_cancelable64 (unsigned int* > futex_word, futex_fatal_error (); > } > } > + > +int > +__futex_abstimed_wait64 (unsigned int* futex_word, unsigned int > expected, > + clockid_t clockid, > + const struct __timespec64* abstime, int > private) +{ > + unsigned int clockbit; > + int err; > + > + /* Work around the fact that the kernel rejects negative timeout > values > + despite them being valid. */ > + if (__glibc_unlikely ((abstime != NULL) && (abstime->tv_sec < 0))) > + return ETIMEDOUT; > + > + if (! lll_futex_supported_clockid(clockid)) > + return EINVAL; > + > + clockbit = (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0; > + int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, > private); + > + err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word, op, > expected, > + abstime, NULL /* Unused. */, > + FUTEX_BITSET_MATCH_ANY); > +#ifndef __ASSUME_TIME64_SYSCALLS > + if (err == -ENOSYS) > + err = __futex_abstimed_wait32 (futex_word, expected, > + clockid, abstime, private); > +#endif > + switch (err) > + { > + case 0: > + case -EAGAIN: > + case -EINTR: > + case -ETIMEDOUT: > + return -err; > + > + case -EFAULT: /* Must have been caused by a glibc or application > bug. */ > + case -EINVAL: /* Either due to wrong alignment, unsupported > + clockid or due to the timeout not being > + normalized. Must have been caused by a glibc or > + application bug. */ > + case -ENOSYS: /* Must have been caused by a glibc bug. */ > + /* No other errors are documented at this time. */ > + default: > + futex_fatal_error (); > + } > +} > diff --git a/sysdeps/nptl/futex-internal.h > b/sysdeps/nptl/futex-internal.h index 7f3910ad98..1ba0d61938 100644 > --- a/sysdeps/nptl/futex-internal.h > +++ b/sysdeps/nptl/futex-internal.h > @@ -529,4 +529,10 @@ __futex_abstimed_wait_cancelable64 (unsigned > int* futex_word, const struct __timespec64* abstime, > int private) attribute_hidden; > > +int > +__futex_abstimed_wait64 (unsigned int* futex_word, unsigned int > expected, > + clockid_t clockid, > + const struct __timespec64* abstime, > + int private) attribute_hidden; > + > #endif /* futex-internal.h */ > diff --git a/sysdeps/unix/sysv/linux/m68k/Makefile > b/sysdeps/unix/sysv/linux/m68k/Makefile index be40fae68a..65164c5752 > 100644 --- a/sysdeps/unix/sysv/linux/m68k/Makefile > +++ b/sysdeps/unix/sysv/linux/m68k/Makefile > @@ -21,3 +21,5 @@ sysdep-dl-routines += dl-static > sysdep-others += lddlibc4 > install-bin += lddlibc4 > endif > + > +CFLAGS-futex-internal.c += -fno-inline Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de