From: Vincenzo Frascino <vincenzo.frascino@arm.com> To: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will.deacon@arm.com>, Arnd Bergmann <arnd@arndb.de>, 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>, Huw Davies <huw@codeweavers.com> Subject: [PATCH v6 01/19] kernel: Standardize vdso_datapage Date: Thu, 30 May 2019 15:15:13 +0100 [thread overview] Message-ID: <20190530141531.43462-2-vincenzo.frascino@arm.com> (raw) In-Reply-To: <20190530141531.43462-1-vincenzo.frascino@arm.com> In an effort to unify the common code for managing the vdso library in between all the architectures that support it, this patch tries to provide a common format for the vdso datapage. As a result of this, this patch generalized the data structures in vgtod.h from x86 private includes to general includes (include/vdso). Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> --- include/vdso/datapage.h | 91 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 include/vdso/datapage.h diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h new file mode 100644 index 000000000000..bb7087eec9bd --- /dev/null +++ b/include/vdso/datapage.h @@ -0,0 +1,91 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __VDSO_DATAPAGE_H +#define __VDSO_DATAPAGE_H + +#ifdef __KERNEL__ + +#ifndef __ASSEMBLY__ + +#include <linux/bits.h> +#include <linux/time.h> +#include <linux/types.h> + +#define VDSO_BASES (CLOCK_TAI + 1) +#define VDSO_HRES (BIT(CLOCK_REALTIME) | \ + BIT(CLOCK_MONOTONIC) | \ + BIT(CLOCK_BOOTTIME) | \ + BIT(CLOCK_TAI)) +#define VDSO_COARSE (BIT(CLOCK_REALTIME_COARSE) | \ + BIT(CLOCK_MONOTONIC_COARSE)) +#define VDSO_RAW (BIT(CLOCK_MONOTONIC_RAW)) + +#define CS_HRES_COARSE 0 +#define CS_RAW 1 +#define CS_BASES (CS_RAW + 1) + +/** + * struct vdso_timestamp - basetime per clock_id + * @sec: seconds + * @nsec: nanoseconds + * + * There is one vdso_timestamp object in vvar for each vDSO-accelerated + * clock_id. For high-resolution clocks, this encodes the time + * corresponding to vdso_data.cycle_last. For coarse clocks this encodes + * the actual time. + * + * To be noticed that for highres clocks nsec is left-shifted by + * vdso_data.cs[x].shift. + */ +struct vdso_timestamp { + u64 sec; + u64 nsec; +}; + +/** + * struct vdso_data - vdso datapage representation + * @seq: timebase sequence counter + * @clock_mode: clock mode + * @cycle_last: timebase at clocksource init + * @mask: clocksource mask + * @mult: clocksource multiplier + * @shift: clocksource shift + * @basetime[clock_id]: basetime per clock_id + * @tz_minuteswest: minutes west of Greenwich + * @tz_dsttime: type of DST correction + * @hrtimer_res: hrtimer resolution + * + * vdso_data will be accessed by 64 bit and compat code at the same time + * so we should be careful before modifying this structure. + */ +struct vdso_data { + u32 seq; + + s32 clock_mode; + u64 cycle_last; + u64 mask; + u32 mult; + u32 shift; + + struct vdso_timestamp basetime[VDSO_BASES]; + + s32 tz_minuteswest; + s32 tz_dsttime; + u32 hrtimer_res; +}; + +/* + * We use the hidden visibility to prevent the compiler from generating a GOT + * relocation. Not only is going through a GOT useless (the entry couldn't and + * must not be overridden by another library), it does not even work: the linker + * cannot generate an absolute address to the data page. + * + * With the hidden visibility, the compiler simply generates a PC-relative + * relocation, and this is what we need. + */ +extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden"))); + +#endif /* !__ASSEMBLY__ */ + +#endif /* __KERNEL__ */ + +#endif /* __VDSO_DATAPAGE_H */ -- 2.21.0
next prev parent reply other threads:[~2019-05-30 14:17 UTC|newest] Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-05-30 14:15 [PATCH v6 00/19] Unify vDSOs across more architectures Vincenzo Frascino 2019-05-30 14:15 ` Vincenzo Frascino [this message] 2019-05-31 8:16 ` [PATCH v6 01/19] kernel: Standardize vdso_datapage Arnd Bergmann 2019-06-04 12:05 ` Vincenzo Frascino 2019-06-10 17:47 ` Huw Davies 2019-06-10 9:27 ` Huw Davies 2019-06-10 10:17 ` Vincenzo Frascino 2019-06-10 10:31 ` Huw Davies 2019-06-10 11:07 ` Vincenzo Frascino 2019-06-10 11:37 ` Huw Davies 2019-05-30 14:15 ` [PATCH v6 02/19] kernel: Define gettimeofday vdso common code Vincenzo Frascino 2019-05-31 8:19 ` Arnd Bergmann 2019-06-04 12:08 ` Vincenzo Frascino 2019-06-10 9:31 ` Huw Davies 2019-06-10 10:18 ` Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 03/19] kernel: Unify update_vsyscall implementation Vincenzo Frascino 2019-06-10 9:34 ` Huw Davies 2019-06-10 10:19 ` Vincenzo Frascino 2019-06-14 11:10 ` Thomas Gleixner 2019-06-14 12:15 ` Vincenzo Frascino 2019-06-14 12:19 ` Thomas Gleixner 2019-06-14 12:25 ` Vincenzo Frascino 2019-06-14 13:07 ` Thomas Gleixner 2019-05-30 14:15 ` [PATCH v6 04/19] arm64: Substitute gettimeofday with C implementation Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 05/19] arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 06/19] arm64: compat: Add missing syscall numbers Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 07/19] arm64: compat: Expose signal related structures Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 08/19] arm64: compat: Generate asm offsets for signals Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 09/19] lib: vdso: Add compat support Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 10/19] arm64: compat: Add vDSO Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 11/19] arm64: Refactor vDSO code Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 12/19] arm64: compat: vDSO setup for compat layer Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 13/19] arm64: elf: vDSO code page discovery Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 14/19] arm64: compat: Get sigreturn trampolines from vDSO Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 15/19] arm64: Add vDSO compat support Vincenzo Frascino 2019-06-01 9:38 ` Catalin Marinas 2019-06-04 12:10 ` Vincenzo Frascino 2019-05-30 14:15 ` [PATCH v6 16/19] arm: Add support for generic vDSO Vincenzo Frascino 2019-05-31 8:32 ` Arnd Bergmann 2019-05-30 14:15 ` [PATCH v6 17/19] mips: " Vincenzo Frascino 2019-05-31 8:34 ` Arnd Bergmann 2019-06-03 14:54 ` Mark Salyzyn 2019-06-03 17:07 ` Arnd Bergmann 2019-05-30 14:15 ` [PATCH v6 18/19] x86: " Vincenzo Frascino 2019-05-30 15:41 ` Michael Kelley 2019-06-04 12:13 ` Vincenzo Frascino 2019-06-14 11:15 ` Thomas Gleixner 2019-06-14 21:17 ` Sasha Levin 2019-06-22 14:46 ` Thomas Gleixner 2019-06-23 19:09 ` Sasha Levin 2019-06-23 21:58 ` Stephen Rothwell 2019-06-24 0:24 ` Sasha Levin 2019-06-24 1:20 ` Stephen Rothwell 2019-06-23 22:12 ` Thomas Gleixner 2019-06-24 0:04 ` Michael Kelley 2019-06-24 0:25 ` Thomas Gleixner 2019-06-28 18:40 ` Michael Kelley 2019-05-30 14:15 ` [PATCH v6 19/19] kselftest: Extend vDSO selftest Vincenzo Frascino 2019-05-31 8:53 ` Arnd Bergmann 2019-05-31 8:46 ` [PATCH v6 00/19] Unify vDSOs across more architectures Arnd Bergmann 2019-06-04 12:04 ` Vincenzo Frascino 2019-06-04 12:12 ` Arnd Bergmann 2019-06-05 14:32 ` Vincenzo Frascino 2019-06-14 12:16 ` Thomas Gleixner 2019-06-14 12:19 ` Vincenzo Frascino 2019-06-20 6:17 ` Shijith Thotton 2019-06-20 8:55 ` Vincenzo Frascino 2019-06-20 16:27 ` Andre Przywara 2019-06-21 9:11 ` Vincenzo Frascino
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20190530141531.43462-2-vincenzo.frascino@arm.com \ --to=vincenzo.frascino@arm.com \ --cc=0x7f454c46@gmail.com \ --cc=arnd@arndb.de \ --cc=catalin.marinas@arm.com \ --cc=daniel.lezcano@linaro.org \ --cc=huw@codeweavers.com \ --cc=linux-arch@vger.kernel.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-kselftest@vger.kernel.org \ --cc=linux-mips@vger.kernel.org \ --cc=linux@armlinux.org.uk \ --cc=linux@rasmusvillemoes.dk \ --cc=paul.burton@mips.com \ --cc=pcc@google.com \ --cc=ralf@linux-mips.org \ --cc=salyzyn@android.com \ --cc=shuah@kernel.org \ --cc=tglx@linutronix.de \ --cc=will.deacon@arm.com \ --subject='Re: [PATCH v6 01/19] kernel: Standardize vdso_datapage' \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).