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author | Vincenzo Frascino <vincenzo.frascino@arm.com> | 2019-06-21 10:52:31 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2019-06-22 21:21:06 +0200 |
commit | 28b1a824a4f44da46983cd2c3249f910bd4b797b (patch) | |
tree | 9e763b48cb41f168181b325db4939d328567bac6 /arch/arm64/kernel/vdso.c | |
parent | 44f57d788e7deecb504843534081d3449c2eede9 (diff) | |
download | lwn-28b1a824a4f44da46983cd2c3249f910bd4b797b.tar.gz lwn-28b1a824a4f44da46983cd2c3249f910bd4b797b.zip |
arm64: vdso: Substitute gettimeofday() with C implementation
To take advantage of the commonly defined vdso interface for gettimeofday()
the architectural code requires an adaptation.
Re-implement the gettimeofday VDSO in C in order to use lib/vdso.
With the new implementation arm64 gains support for CLOCK_BOOTTIME
and CLOCK_TAI.
[ tglx: Reformatted the function line breaks ]
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shijith Thotton <sthotton@marvell.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-5-vincenzo.frascino@arm.com
Diffstat (limited to 'arch/arm64/kernel/vdso.c')
-rw-r--r-- | arch/arm64/kernel/vdso.c | 51 |
1 files changed, 5 insertions, 46 deletions
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 663b166241d0..478ec865a413 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -20,11 +20,13 @@ #include <linux/slab.h> #include <linux/timekeeper_internal.h> #include <linux/vmalloc.h> +#include <vdso/datapage.h> +#include <vdso/helpers.h> +#include <vdso/vsyscall.h> #include <asm/cacheflush.h> #include <asm/signal32.h> #include <asm/vdso.h> -#include <asm/vdso_datapage.h> extern char vdso_start[], vdso_end[]; static unsigned long vdso_pages __ro_after_init; @@ -33,10 +35,10 @@ static unsigned long vdso_pages __ro_after_init; * The vDSO data page. */ static union { - struct vdso_data data; + struct vdso_data data[CS_BASES]; u8 page[PAGE_SIZE]; } vdso_data_store __page_aligned_data; -struct vdso_data *vdso_data = &vdso_data_store.data; +struct vdso_data *vdso_data = vdso_data_store.data; #ifdef CONFIG_COMPAT /* @@ -269,46 +271,3 @@ up_fail: up_write(&mm->mmap_sem); return PTR_ERR(ret); } - -/* - * Update the vDSO data page to keep in sync with kernel timekeeping. - */ -void update_vsyscall(struct timekeeper *tk) -{ - u32 use_syscall = !tk->tkr_mono.clock->archdata.vdso_direct; - - ++vdso_data->tb_seq_count; - smp_wmb(); - - vdso_data->use_syscall = use_syscall; - vdso_data->xtime_coarse_sec = tk->xtime_sec; - vdso_data->xtime_coarse_nsec = tk->tkr_mono.xtime_nsec >> - tk->tkr_mono.shift; - vdso_data->wtm_clock_sec = tk->wall_to_monotonic.tv_sec; - vdso_data->wtm_clock_nsec = tk->wall_to_monotonic.tv_nsec; - - /* Read without the seqlock held by clock_getres() */ - WRITE_ONCE(vdso_data->hrtimer_res, hrtimer_resolution); - - if (!use_syscall) { - /* tkr_mono.cycle_last == tkr_raw.cycle_last */ - vdso_data->cs_cycle_last = tk->tkr_mono.cycle_last; - vdso_data->raw_time_sec = tk->raw_sec; - vdso_data->raw_time_nsec = tk->tkr_raw.xtime_nsec; - vdso_data->xtime_clock_sec = tk->xtime_sec; - vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec; - vdso_data->cs_mono_mult = tk->tkr_mono.mult; - vdso_data->cs_raw_mult = tk->tkr_raw.mult; - /* tkr_mono.shift == tkr_raw.shift */ - vdso_data->cs_shift = tk->tkr_mono.shift; - } - - smp_wmb(); - ++vdso_data->tb_seq_count; -} - -void update_vsyscall_tz(void) -{ - vdso_data->tz_minuteswest = sys_tz.tz_minuteswest; - vdso_data->tz_dsttime = sys_tz.tz_dsttime; -} |