mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-01 04:46:42 +07:00
597bc5c00b
Currently the clock_gettime implementation in the VDSO produces a result with microsecond resolution for the cases that are handled without a system call, i.e. CLOCK_REALTIME and CLOCK_MONOTONIC. The nanoseconds field of the result is obtained by computing a microseconds value and multiplying by 1000. This changes the code in the VDSO to do the computation for clock_gettime with nanosecond resolution. That means that the resolution of the result will ultimately depend on the timebase frequency. Because the timestamp in the VDSO datapage (stamp_xsec, the real time corresponding to the timebase count in tb_orig_stamp) is in units of 2^-20 seconds, it doesn't have sufficient resolution for computing a result with nanosecond resolution. Therefore this adds a copy of xtime to the VDSO datapage and updates it in update_gtod() along with the other time-related fields. Signed-off-by: Paul Mackerras <paulus@samba.org>
125 lines
4.2 KiB
C
125 lines
4.2 KiB
C
#ifndef _VDSO_DATAPAGE_H
|
|
#define _VDSO_DATAPAGE_H
|
|
#ifdef __KERNEL__
|
|
|
|
/*
|
|
* Copyright (C) 2002 Peter Bergner <bergner@vnet.ibm.com>, IBM
|
|
* Copyright (C) 2005 Benjamin Herrenschmidy <benh@kernel.crashing.org>,
|
|
* IBM Corp.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
|
|
/*
|
|
* Note about this structure:
|
|
*
|
|
* This structure was historically called systemcfg and exposed to
|
|
* userland via /proc/ppc64/systemcfg. Unfortunately, this became an
|
|
* ABI issue as some proprietary software started relying on being able
|
|
* to mmap() it, thus we have to keep the base layout at least for a
|
|
* few kernel versions.
|
|
*
|
|
* However, since ppc32 doesn't suffer from this backward handicap,
|
|
* a simpler version of the data structure is used there with only the
|
|
* fields actually used by the vDSO.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* If the major version changes we are incompatible.
|
|
* Minor version changes are a hint.
|
|
*/
|
|
#define SYSTEMCFG_MAJOR 1
|
|
#define SYSTEMCFG_MINOR 1
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#include <linux/unistd.h>
|
|
#include <linux/time.h>
|
|
|
|
#define SYSCALL_MAP_SIZE ((__NR_syscalls + 31) / 32)
|
|
|
|
/*
|
|
* So here is the ppc64 backward compatible version
|
|
*/
|
|
|
|
#ifdef CONFIG_PPC64
|
|
|
|
struct vdso_data {
|
|
__u8 eye_catcher[16]; /* Eyecatcher: SYSTEMCFG:PPC64 0x00 */
|
|
struct { /* Systemcfg version numbers */
|
|
__u32 major; /* Major number 0x10 */
|
|
__u32 minor; /* Minor number 0x14 */
|
|
} version;
|
|
|
|
/* Note about the platform flags: it now only contains the lpar
|
|
* bit. The actual platform number is dead and burried
|
|
*/
|
|
__u32 platform; /* Platform flags 0x18 */
|
|
__u32 processor; /* Processor type 0x1C */
|
|
__u64 processorCount; /* # of physical processors 0x20 */
|
|
__u64 physicalMemorySize; /* Size of real memory(B) 0x28 */
|
|
__u64 tb_orig_stamp; /* Timebase at boot 0x30 */
|
|
__u64 tb_ticks_per_sec; /* Timebase tics / sec 0x38 */
|
|
__u64 tb_to_xs; /* Inverse of TB to 2^20 0x40 */
|
|
__u64 stamp_xsec; /* 0x48 */
|
|
__u64 tb_update_count; /* Timebase atomicity ctr 0x50 */
|
|
__u32 tz_minuteswest; /* Minutes west of Greenwich 0x58 */
|
|
__u32 tz_dsttime; /* Type of dst correction 0x5C */
|
|
__u32 dcache_size; /* L1 d-cache size 0x60 */
|
|
__u32 dcache_line_size; /* L1 d-cache line size 0x64 */
|
|
__u32 icache_size; /* L1 i-cache size 0x68 */
|
|
__u32 icache_line_size; /* L1 i-cache line size 0x6C */
|
|
|
|
/* those additional ones don't have to be located anywhere
|
|
* special as they were not part of the original systemcfg
|
|
*/
|
|
__u32 dcache_block_size; /* L1 d-cache block size */
|
|
__u32 icache_block_size; /* L1 i-cache block size */
|
|
__u32 dcache_log_block_size; /* L1 d-cache log block size */
|
|
__u32 icache_log_block_size; /* L1 i-cache log block size */
|
|
__s32 wtom_clock_sec; /* Wall to monotonic clock */
|
|
__s32 wtom_clock_nsec;
|
|
struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
|
|
__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls */
|
|
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
|
|
};
|
|
|
|
#else /* CONFIG_PPC64 */
|
|
|
|
/*
|
|
* And here is the simpler 32 bits version
|
|
*/
|
|
struct vdso_data {
|
|
__u64 tb_orig_stamp; /* Timebase at boot 0x30 */
|
|
__u64 tb_ticks_per_sec; /* Timebase tics / sec 0x38 */
|
|
__u64 tb_to_xs; /* Inverse of TB to 2^20 0x40 */
|
|
__u64 stamp_xsec; /* 0x48 */
|
|
__u32 tb_update_count; /* Timebase atomicity ctr 0x50 */
|
|
__u32 tz_minuteswest; /* Minutes west of Greenwich 0x58 */
|
|
__u32 tz_dsttime; /* Type of dst correction 0x5C */
|
|
__s32 wtom_clock_sec; /* Wall to monotonic clock */
|
|
__s32 wtom_clock_nsec;
|
|
struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
|
|
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
|
|
__u32 dcache_block_size; /* L1 d-cache block size */
|
|
__u32 icache_block_size; /* L1 i-cache block size */
|
|
__u32 dcache_log_block_size; /* L1 d-cache log block size */
|
|
__u32 icache_log_block_size; /* L1 i-cache log block size */
|
|
};
|
|
|
|
#endif /* CONFIG_PPC64 */
|
|
|
|
#ifdef __KERNEL__
|
|
extern struct vdso_data *vdso_data;
|
|
#endif
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _SYSTEMCFG_H */
|