From: Arnd Bergmann <arnd@arndb.de>
To: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-arch <linux-arch@vger.kernel.org>,
Shuah Khan <shuah@kernel.org>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>,
Catalin Marinas <catalin.marinas@arm.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Will Deacon <will.deacon@arm.com>,
Russell King <linux@armlinux.org.uk>,
Ralf Baechle <ralf@linux-mips.org>,
Mark Salyzyn <salyzyn@android.com>,
Paul Burton <paul.burton@mips.com>,
Dmitry Safonov <0x7f454c46@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Collingbourne <pcc@google.com>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v5 02/23] kernel: Define gettimeofday vdso common code
Date: Fri, 22 Feb 2019 14:49:26 +0100 [thread overview]
Message-ID: <CAK8P3a1ssUdsqk7YW-tjD-dihEAP-voKLOEGO-W=TL7Lb8E7vw@mail.gmail.com> (raw)
In-Reply-To: <20190222122430.21180-3-vincenzo.frascino@arm.com>
On Fri, Feb 22, 2019 at 1:25 PM Vincenzo Frascino
<vincenzo.frascino@arm.com> wrote:
> +/*
> + * The definitions below are required to overcome the limitations
> + * of time_t on 32 bit architectures, which overflows in 2038.
> + * The new code should use the replacements based on time64_t and
> + * timespec64.
> + *
> + * The abstraction below will be updated once the migration to
> + * time64_t is complete.
> + */
> +#ifdef CONFIG_GENERIC_VDSO_32
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#ifdef ENABLE_COMPAT_VDSO
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#define __vdso_timespec __kernel_timespec
> +#define __vdso_timeval __kernel_old_timeval
> +#endif /* CONFIG_COMPAT_VDSO */
> +#endif /* CONFIG_GENERIC_VDSO_32 */
I don't think we need __vdso_timeval at all, just use
__kernel_old_timeval everywhere. There is no generic
64-bit timeval type in the kernel, and there won't be because
gettimeofday() is deprecated.
For __vdso_timespec, I see how you ended up with this
redefinition, and it makes the current version of your patches
easier, but I fear it will in turn make it harder to add the
__kernel_old_timeval based variant.
What I'd prefer to see here is to always use the fixed length
types everywhere in the code, such as
static notrace int __cvdso_clock_gettime64(clockid_t clock,
struct __kernel_timespec *ts)
{
... /* normal clock_gettime using 64-bit times */
}
static notrace int __cvdso_clock_gettime32(clockid_t clock,
struct old_timespec32 *ts32)
{
struct __kernel_timespec ts;
int ret = __cvdso_clock_gettime64(clock, &ts);
ts32->tv_sec = ts->tv_sec;
ts32->tv_nsec = ts->tv_nsec;
return ret;
}
and then have two different versions for 32-bit and 64-bit
architectures, calling one or the other function of the
generic code.
Arnd
WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de>
To: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-arch <linux-arch@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
Russell King <linux@armlinux.org.uk>,
Ralf Baechle <ralf@linux-mips.org>,
Paul Burton <paul.burton@mips.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
Mark Salyzyn <salyzyn@android.com>,
Peter Collingbourne <pcc@google.com>,
Shuah Khan <shuah@kernel.org>,
Dmitry Safonov <0x7f454c46@gmail.com>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>
Subject: Re: [PATCH v5 02/23] kernel: Define gettimeofday vdso common code
Date: Fri, 22 Feb 2019 14:49:26 +0100 [thread overview]
Message-ID: <CAK8P3a1ssUdsqk7YW-tjD-dihEAP-voKLOEGO-W=TL7Lb8E7vw@mail.gmail.com> (raw)
Message-ID: <20190222134926.z_u4ydX3MqwR_EXkWTuG7FQFgJpAehhaGPB72vfz0gM@z> (raw)
In-Reply-To: <20190222122430.21180-3-vincenzo.frascino@arm.com>
On Fri, Feb 22, 2019 at 1:25 PM Vincenzo Frascino
<vincenzo.frascino@arm.com> wrote:
> +/*
> + * The definitions below are required to overcome the limitations
> + * of time_t on 32 bit architectures, which overflows in 2038.
> + * The new code should use the replacements based on time64_t and
> + * timespec64.
> + *
> + * The abstraction below will be updated once the migration to
> + * time64_t is complete.
> + */
> +#ifdef CONFIG_GENERIC_VDSO_32
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#ifdef ENABLE_COMPAT_VDSO
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#define __vdso_timespec __kernel_timespec
> +#define __vdso_timeval __kernel_old_timeval
> +#endif /* CONFIG_COMPAT_VDSO */
> +#endif /* CONFIG_GENERIC_VDSO_32 */
I don't think we need __vdso_timeval at all, just use
__kernel_old_timeval everywhere. There is no generic
64-bit timeval type in the kernel, and there won't be because
gettimeofday() is deprecated.
For __vdso_timespec, I see how you ended up with this
redefinition, and it makes the current version of your patches
easier, but I fear it will in turn make it harder to add the
__kernel_old_timeval based variant.
What I'd prefer to see here is to always use the fixed length
types everywhere in the code, such as
static notrace int __cvdso_clock_gettime64(clockid_t clock,
struct __kernel_timespec *ts)
{
... /* normal clock_gettime using 64-bit times */
}
static notrace int __cvdso_clock_gettime32(clockid_t clock,
struct old_timespec32 *ts32)
{
struct __kernel_timespec ts;
int ret = __cvdso_clock_gettime64(clock, &ts);
ts32->tv_sec = ts->tv_sec;
ts32->tv_nsec = ts->tv_nsec;
return ret;
}
and then have two different versions for 32-bit and 64-bit
architectures, calling one or the other function of the
generic code.
Arnd
WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de>
To: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-arch <linux-arch@vger.kernel.org>,
Shuah Khan <shuah@kernel.org>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>,
Catalin Marinas <catalin.marinas@arm.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Will Deacon <will.deacon@arm.com>,
Russell King <linux@armlinux.org.uk>,
Ralf Baechle <ralf@linux-mips.org>,
Mark Salyzyn <salyzyn@android.com>,
Paul Burton <paul.burton@mips.com>,
Dmitry Safonov <0x7f454c46@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Collingbourne <pcc@google.com>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v5 02/23] kernel: Define gettimeofday vdso common code
Date: Fri, 22 Feb 2019 14:49:26 +0100 [thread overview]
Message-ID: <CAK8P3a1ssUdsqk7YW-tjD-dihEAP-voKLOEGO-W=TL7Lb8E7vw@mail.gmail.com> (raw)
In-Reply-To: <20190222122430.21180-3-vincenzo.frascino@arm.com>
On Fri, Feb 22, 2019 at 1:25 PM Vincenzo Frascino
<vincenzo.frascino@arm.com> wrote:
> +/*
> + * The definitions below are required to overcome the limitations
> + * of time_t on 32 bit architectures, which overflows in 2038.
> + * The new code should use the replacements based on time64_t and
> + * timespec64.
> + *
> + * The abstraction below will be updated once the migration to
> + * time64_t is complete.
> + */
> +#ifdef CONFIG_GENERIC_VDSO_32
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#ifdef ENABLE_COMPAT_VDSO
> +#define __vdso_timespec old_timespec32
> +#define __vdso_timeval old_timeval32
> +#else
> +#define __vdso_timespec __kernel_timespec
> +#define __vdso_timeval __kernel_old_timeval
> +#endif /* CONFIG_COMPAT_VDSO */
> +#endif /* CONFIG_GENERIC_VDSO_32 */
I don't think we need __vdso_timeval at all, just use
__kernel_old_timeval everywhere. There is no generic
64-bit timeval type in the kernel, and there won't be because
gettimeofday() is deprecated.
For __vdso_timespec, I see how you ended up with this
redefinition, and it makes the current version of your patches
easier, but I fear it will in turn make it harder to add the
__kernel_old_timeval based variant.
What I'd prefer to see here is to always use the fixed length
types everywhere in the code, such as
static notrace int __cvdso_clock_gettime64(clockid_t clock,
struct __kernel_timespec *ts)
{
... /* normal clock_gettime using 64-bit times */
}
static notrace int __cvdso_clock_gettime32(clockid_t clock,
struct old_timespec32 *ts32)
{
struct __kernel_timespec ts;
int ret = __cvdso_clock_gettime64(clock, &ts);
ts32->tv_sec = ts->tv_sec;
ts32->tv_nsec = ts->tv_nsec;
return ret;
}
and then have two different versions for 32-bit and 64-bit
architectures, calling one or the other function of the
generic code.
Arnd
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http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-02-22 13:49 UTC|newest]
Thread overview: 178+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-22 12:24 [PATCH v5 00/23] Unify vDSOs across more architectures Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 01/23] kernel: Standardize vdso_datapage Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:58 ` Mark Rutland
2019-02-22 12:58 ` Mark Rutland
2019-02-22 12:58 ` Mark Rutland
2019-02-23 16:51 ` Thomas Gleixner
2019-02-23 16:51 ` Thomas Gleixner
2019-02-23 16:51 ` Thomas Gleixner
2019-02-27 14:23 ` Vincenzo Frascino
2019-02-27 14:23 ` Vincenzo Frascino
2019-02-27 14:23 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 02/23] kernel: Define gettimeofday vdso common code Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 13:34 ` Mark Rutland
2019-02-22 13:34 ` Mark Rutland
2019-02-22 13:34 ` Mark Rutland
2019-02-22 13:49 ` Arnd Bergmann [this message]
2019-02-22 13:49 ` Arnd Bergmann
2019-02-22 13:49 ` Arnd Bergmann
2019-02-22 14:36 ` Arnd Bergmann
2019-02-22 14:36 ` Arnd Bergmann
2019-02-22 14:36 ` Arnd Bergmann
2019-02-27 14:52 ` Vincenzo Frascino
2019-02-27 14:52 ` Vincenzo Frascino
2019-02-27 14:52 ` Vincenzo Frascino
2019-02-28 9:29 ` Arnd Bergmann
2019-02-28 9:29 ` Arnd Bergmann
2019-02-28 9:29 ` Arnd Bergmann
2019-02-28 11:58 ` [PATCH 1/2] vdso: use fixed-size time types Arnd Bergmann
2019-02-28 11:58 ` Arnd Bergmann
2019-02-28 11:58 ` Arnd Bergmann
2019-02-28 11:58 ` [PATCH 2/2] vdso: add clock_gettime64 Arnd Bergmann
2019-02-28 11:58 ` Arnd Bergmann
2019-02-28 11:58 ` Arnd Bergmann
2019-02-28 13:42 ` [PATCH 1/2] vdso: use fixed-size time types Thomas Gleixner
2019-02-28 13:42 ` Thomas Gleixner
2019-02-28 13:42 ` Thomas Gleixner
2019-02-28 13:45 ` Vincenzo Frascino
2019-02-28 13:45 ` Vincenzo Frascino
2019-02-28 13:45 ` Vincenzo Frascino
2019-02-23 10:34 ` [PATCH v5 02/23] kernel: Define gettimeofday vdso common code Thomas Gleixner
2019-02-23 10:34 ` Thomas Gleixner
2019-02-23 10:34 ` Thomas Gleixner
2019-02-25 14:09 ` Vincenzo Frascino
2019-02-25 14:09 ` Vincenzo Frascino
2019-02-25 14:09 ` Vincenzo Frascino
2019-02-23 17:31 ` Thomas Gleixner
2019-02-23 17:31 ` Thomas Gleixner
2019-02-23 17:31 ` Thomas Gleixner
2019-02-27 13:47 ` Vincenzo Frascino
2019-02-27 13:47 ` Vincenzo Frascino
2019-02-27 13:47 ` Vincenzo Frascino
2019-02-27 15:49 ` Thomas Gleixner
2019-02-27 15:49 ` Thomas Gleixner
2019-02-27 15:49 ` Thomas Gleixner
2019-02-27 16:06 ` Vincenzo Frascino
2019-02-27 16:06 ` Vincenzo Frascino
2019-02-27 16:06 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 03/23] arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 04/23] arm64: Substitute gettimeofday with C implementation Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 13:42 ` Mark Rutland
2019-02-22 13:42 ` Mark Rutland
2019-02-22 13:42 ` Mark Rutland
2019-02-22 12:24 ` [PATCH v5 05/23] arm64: compat: Alloc separate pages for vectors and sigpage Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 06/23] arm64: compat: Split kuser32 Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 07/23] arm64: compat: Refactor aarch32_alloc_vdso_pages() Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 08/23] arm64: compat: Add KUSER_HELPERS config option Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 14:04 ` Mark Rutland
2019-02-22 14:04 ` Mark Rutland
2019-02-22 14:04 ` Mark Rutland
2019-02-22 14:09 ` Russell King - ARM Linux admin
2019-02-22 14:09 ` Russell King - ARM Linux admin
2019-02-22 14:09 ` Russell King - ARM Linux admin
2019-02-26 12:10 ` Vincenzo Frascino
2019-02-26 12:10 ` Vincenzo Frascino
2019-02-26 12:10 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 09/23] arm64: compat: Add missing syscall numbers Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 10/23] arm64: compat: Expose signal related structures Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 11/23] arm64: compat: Generate asm offsets for signals Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 14:22 ` Mark Rutland
2019-02-22 14:22 ` Mark Rutland
2019-02-22 14:22 ` Mark Rutland
2019-02-22 12:24 ` [PATCH v5 12/23] lib: vdso: Add compat support Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 13/23] arm64: compat: Add vDSO Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 14:32 ` Mark Rutland
2019-02-22 14:32 ` Mark Rutland
2019-02-22 14:32 ` Mark Rutland
2019-02-22 12:24 ` [PATCH v5 14/23] arm64: Refactor vDSO code Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 14:37 ` Mark Rutland
2019-02-22 14:37 ` Mark Rutland
2019-02-22 14:37 ` Mark Rutland
2019-02-22 12:24 ` [PATCH v5 15/23] arm64: compat: vDSO setup for compat layer Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 16/23] arm64: elf: vDSO code page discovery Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 17/23] arm64: compat: Get sigreturn trampolines from vDSO Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 18/23] arm64: Add vDSO compat support Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 19/23] arm64: Enable compat vDSO support Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 14:39 ` Mark Rutland
2019-02-22 14:39 ` Mark Rutland
2019-02-22 14:39 ` Mark Rutland
2019-02-22 14:41 ` Mark Rutland
2019-02-22 14:41 ` Mark Rutland
2019-02-22 14:41 ` Mark Rutland
2019-02-22 12:24 ` [PATCH v5 20/23] arm: Add support for generic vDSO Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 21/23] mips: " Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 22/23] x86: " Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-23 10:45 ` Thomas Gleixner
2019-02-23 10:45 ` Thomas Gleixner
2019-02-23 10:45 ` Thomas Gleixner
2019-02-27 16:18 ` Vincenzo Frascino
2019-02-27 16:18 ` Vincenzo Frascino
2019-02-27 16:18 ` Vincenzo Frascino
2019-02-22 12:24 ` [PATCH v5 23/23] kselftest: Extend vDSO selftest Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-22 12:24 ` Vincenzo Frascino
2019-02-23 17:39 ` [PATCH v5 00/23] Unify vDSOs across more architectures Thomas Gleixner
2019-02-23 17:39 ` Thomas Gleixner
2019-02-23 17:39 ` Thomas Gleixner
2019-02-28 11:40 ` Arnd Bergmann
2019-02-28 11:40 ` Arnd Bergmann
2019-02-28 12:09 ` Vincenzo Frascino
2019-02-28 12:09 ` Vincenzo Frascino
2019-02-28 12:38 ` Arnd Bergmann
2019-02-28 12:38 ` Arnd Bergmann
2019-02-28 12:38 ` Arnd Bergmann
2019-02-28 12:42 ` Vincenzo Frascino
2019-02-28 12:42 ` Vincenzo Frascino
2019-02-28 12:42 ` Vincenzo Frascino
2019-02-28 13:54 ` Arnd Bergmann
2019-02-28 13:54 ` Arnd Bergmann
2019-02-28 13:54 ` Arnd Bergmann
2019-02-28 15:51 ` Vincenzo Frascino
2019-02-28 15:51 ` Vincenzo Frascino
2019-02-28 15:51 ` Vincenzo Frascino
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