[PATCH 6/6] linux: Use 32-bit time_t for rusage
Lukasz Majewski
lukma@denx.de
Tue Feb 4 14:23:00 GMT 2020
Hi Alistair,
> The Linux kernel expects rusage to use a 32-bit time_t, even on archs
> with a 64-bit time_t (like RV32). To address this let's convert
> rusage to/from 32-bit and 64-bit to ensure the kernel always gets
> a 32-bit time_t.
>
> This means that all 32-bit architectures with a 64-bit time_t will be
> able to use this generic implementation.
>
> This code is based on similar code in alpha, but adjusted to pass the
> 32-bit time_t to the kernel.
>
> We can't directly call __wait4 as it expects a struct rusage but we
> have to pass in and use a struct rusage32. The same appies to
> __getrusage. ---
> include/sys/resource.h | 6 ++
> .../linux/generic/wordsize-32/getrusage.c | 52 ++++++++++++
I wanted to test this code with ARM Y2038 test setup (yocto with qemu).
Unfortunately, for ARM32 (armv7) the path:
sysdeps/unix/sysv/linux/generic/wordsize-32/ is not reached at all.
In the build log (with make --debug) I do see following paths:
config_sysdirs='sysdeps/unix/sysv/linux/arm/le
sysdeps/unix/sysv/linux/arm sysdeps/arm/nptl sysdeps/unix/sysv/linux
sysdeps/nptl sysdeps/pthread sysdeps/gnu sysdeps/unix/inet
sysdeps/unix/sysv sysdeps/unix/arm sysdeps/unix sysdeps/posix
sysdeps/arm/le/armv7/multiarch sysdeps/arm/armv7/multiarch
sysdeps/arm/le/armv7 sysdeps/arm/armv7 sysdeps/arm/armv6t2
sysdeps/arm/armv6 sysdeps/arm/le sysdeps/arm sysdeps/wordsize-32
sysdeps/ieee754/flt-32 sysdeps/ieee754/dbl-64 sysdeps/ieee754
sysdeps/generic'
The "wordsize-32" only appears in ./sysdeps/wordsize-32 (and only
sysdeps/generic is defined for searching files to build).
How shall I tune my setup to also make
sysdeps/unix/sysv/linux/generic/wordsize-32/ accessible for glibc build?
Could you share output from yours build setup:
grep config-sysdir config.make
> .../linux/generic/wordsize-32/tv32-compat.h | 47 +++++++++++
> .../sysv/linux/generic/wordsize-32/wait4.c | 83
> +++++++++++++++++++ 4 files changed, 188 insertions(+)
> create mode 100644
> sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c create mode
> 100644 sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c
>
> diff --git a/include/sys/resource.h b/include/sys/resource.h
> index 9d604dfe3e..fcba56303a 100644
> --- a/include/sys/resource.h
> +++ b/include/sys/resource.h
> @@ -134,5 +134,11 @@ extern int __getrusage (enum __rusage_who __who,
> struct rusage *__usage) extern int __setrlimit (enum
> __rlimit_resource __resource, const struct rlimit *__rlimits);
> libc_hidden_proto (__setrlimit);
> +
> +#if __TIMESIZE == 64
> +# define __getrusage64 __getrusage
> +#else
> +extern int __getrusage64 (enum __rusage_who who, struct __rusage64
Please add libc_hidden_proto (__getrusage64)
> *usage); +#endif
> #endif
> #endif
> diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c
> b/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c new file
> mode 100644 index 0000000000..a495cc6c8b
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/getrusage.c
> @@ -0,0 +1,52 @@
> +/* getrusage -- get the rusage struct. Linux/tv32 version.
> + Copyright (C) 2020 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be
> useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <sys/time.h>
> +#include <sys/resource.h>
> +#include <sysdep.h>
> +#include <tv32-compat.h>
> +
> +int
> +__getrusage64 (enum __rusage_who who, struct __rusage64 *usage)
> +{
> + struct __rusage32 usage32;
> + if (INLINE_SYSCALL_CALL (getrusage, who, &usage32) == -1)
> + return -1;
> +
> + rusage32_to_rusage64 (&usage32, usage);
> + return 0;
> +}
> +
> +#if __TIMESIZE != 64
Please add libc_hidden_def (__getrusage64)
> +int
> +__getrusage (enum __rusage_who who, struct rusage *usage)
> +{
> + int ret ;
> + struct __rusage64 usage64;
> +
> + ret = __getrusage64 (who, &usage64);
> +
> + if (ret != 0)
> + return ret;
> +
> + rusage64_to_rusage (&usage64, usage);
> +
> + return ret;
> +}
> +#endif
> +weak_alias (__getrusage, getrusage)
Ok.
> diff --git
> a/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h
> b/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h index
> 4eb6f216ea..c2231f042f 100644 ---
> a/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h +++
> b/sysdeps/unix/sysv/linux/generic/wordsize-32/tv32-compat.h @@ -24,6
> +24,7 @@ #include <bits/types.h> #include <bits/types/time_t.h>
> #include <bits/types/struct_timeval.h>
> +#include <sys/resource.h>
>
> /* Structures containing 'struct timeval' with 32-bit time_t. */
> struct __itimerval32
> @@ -32,4 +33,50 @@ struct __itimerval32
> struct __timeval32 it_value;
> };
>
> +struct __rusage32
> +{
> + struct __timeval32 ru_utime; /* user time used */
> + struct __timeval32 ru_stime; /* system time used */
> + long ru_maxrss; /* maximum resident set size */
> + long ru_ixrss; /* integral shared memory size */
> + long ru_idrss; /* integral unshared data size */
> + long ru_isrss; /* integral unshared stack size */
> + long ru_minflt; /* page reclaims */
> + long ru_majflt; /* page faults */
> + long ru_nswap; /* swaps */
> + long ru_inblock; /* block input operations */
> + long ru_oublock; /* block output operations */
> + long ru_msgsnd; /* messages sent */
> + long ru_msgrcv; /* messages received */
> + long ru_nsignals; /* signals received */
> + long ru_nvcsw; /* voluntary context switches */
> + long ru_nivcsw; /* involuntary " */
> +};
> +
> +static inline void
> +rusage32_to_rusage64 (const struct __rusage32 *restrict r32,
> + struct __rusage64 *restrict r64)
> +{
> + /* Make sure the entire output structure is cleared, including
> + padding and reserved fields. */
> + memset (r64, 0, sizeof *r64);
> +
> + r64->ru_utime = valid_timeval32_to_timeval64 (r32->ru_utime);
> + r64->ru_stime = valid_timeval32_to_timeval64 (r32->ru_stime);
> + r64->ru_maxrss = r32->ru_maxrss;
> + r64->ru_ixrss = r32->ru_ixrss;
> + r64->ru_idrss = r32->ru_idrss;
> + r64->ru_isrss = r32->ru_isrss;
> + r64->ru_minflt = r32->ru_minflt;
> + r64->ru_majflt = r32->ru_majflt;
> + r64->ru_nswap = r32->ru_nswap;
> + r64->ru_inblock = r32->ru_inblock;
> + r64->ru_oublock = r32->ru_oublock;
> + r64->ru_msgsnd = r32->ru_msgsnd;
> + r64->ru_msgrcv = r32->ru_msgrcv;
> + r64->ru_nsignals = r32->ru_nsignals;
> + r64->ru_nvcsw = r32->ru_nvcsw;
> + r64->ru_nivcsw = r32->ru_nivcsw;
> +}
> +
> #endif /* tv32-compat.h */
> diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c
> b/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c new file mode
> 100644 index 0000000000..ae42b2ecbb
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/generic/wordsize-32/wait4.c
> @@ -0,0 +1,83 @@
> +/* wait4 -- wait for process to change state. Linux/RV32/tv32
> version.
> + Copyright (C) 2020 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be
> useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <sys/wait.h>
> +#include <sys/resource.h>
> +#include <sysdep-cancel.h>
> +#include <tv32-compat.h>
> +
> +pid_t
> +__wait4 (pid_t pid, int *stat_loc, int options, struct rusage *usage)
If I may have one "small" remark - it seems like wait4 uses here struct
rusage.
Would it be a big problem if you provide 64 bit conversion for this
function as well?
I mean the conversion code for it:
pid_t
__wait4_time64 (pid_t pid, int *stat_loc, int options, struct __rusage64
*usage)
{
}
#if __TIMESIZE != 64
pid_t
__wait4 (pid_t pid, int *stat_loc, int options, struct rusage *usage)
{
//conversions
ret = __wait4_time64 ()
//conversions
}
#endif
> +{
> + struct __rusage32 usage32;
> + idtype_t idtype = P_PID;
> +
> + if (pid < -1)
> + {
> + idtype = P_PGID;
> + pid *= -1;
> + }
> + else if (pid == -1)
> + idtype = P_ALL;
> + else if (pid == 0)
> + idtype = P_PGID;
> +
> + options |= WEXITED;
> +
> + siginfo_t infop;
> + if (SYSCALL_CANCEL (waitid, idtype, pid, &infop, options,
> &usage32) < 0)
> + return -1;
> +
> + if (stat_loc)
> + {
> + switch (infop.si_code)
> + {
> + case CLD_EXITED:
> + *stat_loc = W_EXITCODE (infop.si_status, 0);
> + break;
> + case CLD_DUMPED:
> + *stat_loc = WCOREFLAG | infop.si_status;
> + break;
> + case CLD_KILLED:
> + *stat_loc = infop.si_status;
> + break;
> + case CLD_TRAPPED:
> + case CLD_STOPPED:
> + *stat_loc = W_STOPCODE (infop.si_status);
> + break;
> + case CLD_CONTINUED:
> + *stat_loc = __W_CONTINUED;
> + break;
> + default:
> + *stat_loc = 0;
> + break;
> + }
> + }
> +
> + if (usage != NULL)
> + {
> + struct __rusage64 usage64;
> + rusage32_to_rusage64 (&usage32, &usage64);
> + rusage64_to_rusage (&usage64, usage);
> + }
> +
> + return infop.si_pid;
> +}
> +
> +libc_hidden_def (__wait4);
> +weak_alias (__wait4, wait4)
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
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