On 27/06/24 06:46, Helge Deller wrote: > * Adhemerval Zanella Netto <adhemerval.zanella@xxxxxxxxxx>: >> >> On 25/06/24 16:48, Helge Deller wrote: >>> On 6/24/24 22:31, Adhemerval Zanella Netto wrote: >>>> >>>> >>>> On 21/06/24 16:26, Helge Deller wrote: >>>>> The upcoming parisc (hppa) v6.11 Linux kernel will include vDSO >>>>> support for gettimeofday(), clock_gettime() and clock_gettime64() >>>>> syscalls for 32- and 64-bit userspace. >>>>> The patch below adds the necessary glue code for glibc. >>>>> >>>>> Signed-off-by: Helge Deller <deller@xxxxxx> >>>>> >>>>> Changes in v2: >>>>> - add vsyscalls for 64-bit too >>>>> >>>>> diff -up ./sysdeps/unix/sysv/linux/hppa/sysdep.h.org ./sysdeps/unix/sysv/linux/hppa/sysdep.h >>>>> --- ./sysdeps/unix/sysv/linux/hppa/sysdep.h.org 2024-06-15 20:20:58.992000000 +0000 >>>>> +++ ./sysdeps/unix/sysv/linux/hppa/sysdep.h 2024-06-21 19:19:02.132000000 +0000 >>>>> @@ -468,6 +468,18 @@ L(pre_end): ASM_LINE_SEP \ >>>>> #define CLOB_ARGS_1 CLOB_ARGS_2, "%r25" >>>>> #define CLOB_ARGS_0 CLOB_ARGS_1, "%r26" >>>>> >>>>> +#define VDSO_NAME "LINUX_6.11" >>>>> +#define VDSO_HASH 182951793 >>>>> + >>>>> +#ifdef __LP64__ >>>>> +# define HAVE_CLOCK_GETTIME_VSYSCALL "__vdso_clock_gettime" >>>>> +# define HAVE_GETTIMEOFDAY_VSYSCALL "__vdso_gettimeofday" >>>>> +#else >>>>> +# define HAVE_CLOCK_GETTIME_VSYSCALL "__vdso_clock_gettime" >>>>> +# define HAVE_CLOCK_GETTIME64_VSYSCALL "__vdso_clock_gettime64" >>>>> +# define HAVE_GETTIMEOFDAY_VSYSCALL "__vdso_gettimeofday" >>>>> +#endif /* __LP64__ */ >>>>> + >>>>> #endif /* __ASSEMBLER__ */ >>>> >>>> Not sure why you have added the gettimeofday support, currently 32 bits >>>> it is already routed to to clock_gettime (which will use >>>> __vdso_clock_gettime64 anyway). >>> >>> Yep, you are right. >>> I actually didn't checked if it's being used but just saw it's defined >>> for other arches too, so I assumed it to be used. >>> >>>> For hppa to actually use, it would require to add a way to call it >>>> for !USE_IFUNC_GETTIMEOFDAY gettimeofday, which I am not it really be >>>> an improvement here. >>> >>> Yes, that doesn't make sense. >>> >>> Looking at the code it seems riscv, sparc, arm, mips and s390 define it >>> too, without being used. Do you suggest we should remove gettimeofday >>> vsyscall from hppa again (or just keep like the others even if not being used)? >> >> The riscv only added it for CONFIG_64BIT, while old ABIs like arm, sparc, >> mips, and s390 added before 64 bit time_t landed on 5.1. With current >> 32 bits ABIs moving to 64 bit time_t userland, there is no much sense in >> providing a 32 bit gettimeofday, nor I think I adding a gettimeoday64 would >> make much sense (maybe on really high sensitive workloads that require >> low-latency timestamping, but clock_gettime would work better anyway). >> >> It is highly unlikely that the symbol will ever be used by userland, >> and I think it only make sense to provide clock_gettime64. The glibc >> 32 bit time_t clock_gettime routes to clock_gettime64 and it will only >> fallback to 32 bit vDSO symbol if the 64 bit time_t one is not present. > > Like patch below? > Helge > > > [PATCH] hppa/vdso: Provide 64-bit clock_gettime() vDSO only > > Adhemerval noticed that the gettimeofday() and 32-bit clock_gettime() > vDSO calls won't be used by glibc on hppa, so there is no need to > declare them. Both syscalls will be emulated by utilizing return values > of the 64-bit clock_gettime() vDSO instead.. > > Signed-off-by: Helge Deller <deller@xxxxxx> > Suggested-by: Adhemerval Zanella Netto <adhemerval.zanella@xxxxxxxxxx> > > diff --git a/sysdeps/unix/sysv/linux/hppa/sysdep.h b/sysdeps/unix/sysv/linux/hppa/sysdep.h > index af62f7501e..e47975e5cf 100644 > --- a/sysdeps/unix/sysv/linux/hppa/sysdep.h > +++ b/sysdeps/unix/sysv/linux/hppa/sysdep.h > @@ -473,11 +473,8 @@ L(pre_end): ASM_LINE_SEP \ > > #ifdef __LP64__ > # define HAVE_CLOCK_GETTIME_VSYSCALL "__vdso_clock_gettime" > -# define HAVE_GETTIMEOFDAY_VSYSCALL "__vdso_gettimeofday" > #else > -# define HAVE_CLOCK_GETTIME_VSYSCALL "__vdso_clock_gettime" > # define HAVE_CLOCK_GETTIME64_VSYSCALL "__vdso_clock_gettime64" > -# define HAVE_GETTIMEOFDAY_VSYSCALL "__vdso_gettimeofday" > #endif /* __LP64__ */ > > #endif /* __ASSEMBLER__ */ Yeah, it seems ok thanks.
