summaryrefslogtreecommitdiff
path: root/include/uapi/linux/patchkey.h
blob: 3eb246e94733f22c137e3b1b7bd97a93dad6dfdb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 * <linux/patchkey.h> -- definition of _PATCHKEY macro
 *
 * Copyright (C) 2005 Stuart Brady
 *
 * This exists because awe_voice.h defined its own _PATCHKEY and it wasn't
 * clear whether removing this would break anything in userspace.
 *
 * Do not include this file directly.  Please use <sys/soundcard.h> instead.
 * For kernel code, use <linux/soundcard.h>
 */

#ifndef _LINUX_PATCHKEY_H_INDIRECT
#error "patchkey.h included directly"
#endif

#ifndef _UAPI_LINUX_PATCHKEY_H
#define _UAPI_LINUX_PATCHKEY_H

/* Endian macros. */
#ifndef __KERNEL__
#  include <endian.h>
#endif

#if !defined(__KERNEL__)
#if defined(__BYTE_ORDER)
#  if __BYTE_ORDER == __BIG_ENDIAN
#    define _PATCHKEY(id) (0xfd00|id)
#  elif __BYTE_ORDER == __LITTLE_ENDIAN
#    define _PATCHKEY(id) ((id<<8)|0x00fd)
#  else
#    error "could not determine byte order"
#  endif
#endif
#endif

#endif /* _UAPI_LINUX_PATCHKEY_H */
ied into the pages. *) During every exec, these pages are mapped into the process through arch_setup_additional_pages and the location of mapping is passed on to the process through aux vector AT_SYSINFO_EHDR which is used by glibc. *) A new update_vsyscall routine for sparc is added to keep the data page in vdso updated. *) As vDSO cannot contain dynamically relocatable references, a new version of cpu_relax is added for the use of vDSO. This change also requires a putback to glibc to use vDSO. For testing, programs planning to try vDSO can be compiled against the generated vdso(64/32).so in the source. Testing: ======== [root@localhost ~]# cat vdso_test.c int main() { struct timespec tv_start, tv_end; struct timeval tv_tmp; int i; int count = 1 * 1000 * 10000; long long diff; clock_gettime(0, &tv_start); for (i = 0; i < count; i++) gettimeofday(&tv_tmp, NULL); clock_gettime(0, &tv_end); diff = (long long)(tv_end.tv_sec - tv_start.tv_sec)*(1*1000*1000*1000); diff += (tv_end.tv_nsec - tv_start.tv_nsec); printf("Start sec: %d\n", tv_start.tv_sec); printf("End sec : %d\n", tv_end.tv_sec); printf("%d cycles in %lld ns = %f ns/cycle\n", count, diff, (double)diff / (double)count); return 0; } [root@localhost ~]# cc vdso_test.c -o t32_without_fix -m32 -lrt [root@localhost ~]# ./t32_without_fix Start sec: 1502396130 End sec : 1502396140 10000000 cycles in 9565148528 ns = 956.514853 ns/cycle [root@localhost ~]# cc vdso_test.c -o t32_with_fix -m32 ./vdso32.so.dbg [root@localhost ~]# ./t32_with_fix Start sec: 1502396168 End sec : 1502396169 10000000 cycles in 798141262 ns = 79.814126 ns/cycle [root@localhost ~]# cc vdso_test.c -o t64_without_fix -m64 -lrt [root@localhost ~]# ./t64_without_fix Start sec: 1502396208 End sec : 1502396218 10000000 cycles in 9846091800 ns = 984.609180 ns/cycle [root@localhost ~]# cc vdso_test.c -o t64_with_fix -m64 ./vdso64.so.dbg [root@localhost ~]# ./t64_with_fix Start sec: 1502396257 End sec : 1502396257 10000000 cycles in 380984048 ns = 38.098405 ns/cycle V1 to V2 Changes: ================= Added hot patching code to switch the read stick instruction to read tick instruction based on the hardware. V2 to V3 Changes: ================= Merged latest changes from sparc-next and moved the initialization of clocksource_tick.archdata.vclock_mode to time_init_early. Disabled queued spinlock and rwlock configuration when simulating 32-bit config to compile 32-bit VDSO. V3 to V4 Changes: ================= Hardcoded the page size as 8192 in linker script for both 64-bit and 32-bit binaries. Removed unused variables in vdso2c.h. Added -mv8plus flag to Makefile to prevent the generation of relocation entries for __lshrdi3 in 32-bit vdso binary. Signed-off-by: Nick Alcock <nick.alcock@oracle.com> Signed-off-by: Nagarathnam Muthusamy <nagarathnam.muthusamy@oracle.com> Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>