sparc,x86: vdso: remove meaningless undefining CONFIG_OPTIMIZE_INLININGThe code, #undef CONFIG_OPTIMIZE_INLINING, is not working as expectedbecause <linux/compiler_types.h> is parsed before vclock
sparc,x86: vdso: remove meaningless undefining CONFIG_OPTIMIZE_INLININGThe code, #undef CONFIG_OPTIMIZE_INLINING, is not working as expectedbecause <linux/compiler_types.h> is parsed before vclock_gettime.c since28128c61e08e ("kconfig.h: Include compiler types to avoid missed structattributes").Since then, <linux/compiler_types.h> is included really early by using the'-include' option. So, you cannot negate the decision of<linux/compiler_types.h> in this way.You can confirm it by checking the pre-processed code, like this: $ make arch/x86/entry/vdso/vdso32/vclock_gettime.iThere is no difference with/without CONFIG_CC_OPTIMIZE_FOR_SIZE.It is about two years since 28128c61e08e. Nobody has reported a problem(or, nobody has even noticed the fact that this code is not working).It is ugly and unreliable to attempt to undefine a CONFIG option from Cfiles, and anyway the inlining heuristic is up to the compiler.Just remove the broken code.Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>Signed-off-by: Andrew Morton <akpm@linux-foundation.org>Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>Cc: Arnd Bergmann <arnd@arndb.de>Cc: Ingo Molnar <mingo@redhat.com>Cc: Thomas Gleixner <tglx@linutronix.de>Cc: Masahiro Yamada <masahiroy@kernel.org>Cc: Borislav Petkov <bp@alien8.de>Cc: "H. Peter Anvin" <hpa@zytor.com>Cc: David Miller <davem@davemloft.net>Link: http://lkml.kernel.org/r/20200220110807.32534-1-masahiroy@kernel.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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.gitignore: add SPDX License IdentifierAdd SPDX License Identifier to all .gitignore files.Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfou
.gitignore: add SPDX License IdentifierAdd SPDX License Identifier to all .gitignore files.Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sparc: Fix VDSO build with older binutils.Older versions of bintutils do not allow symbol math across differentsegments on sparc:====================Assembler messages:99: Error: operation com
sparc: Fix VDSO build with older binutils.Older versions of bintutils do not allow symbol math across differentsegments on sparc:====================Assembler messages:99: Error: operation combines symbols in different segments====================This is controlled by whether or not DIFF_EXPR_OK is defined ingas/config/tc-*.h and for sparc this was not the case until mid-2017.So we have to patch between %stick and %tick another way.Do what powerpc does and emit two versions of the relevant functions,one using %tick and one using %stick, and patch the symbols in thedynamic symbol table.Fixes: 2f6c9bf31a0b ("sparc: Improve VDSO instruction patching.")Reported-by: Meelis Roos <mroos@linux.ee>Tested-by: Meelis Roos <mroos@linux.ee>Signed-off-by: David S. Miller <davem@davemloft.net>
vDSO for sparcFollowing patch is based on work done by Nick Alcock on 64-bit vDSO for sparcin Oracle linux. I have extended it to include support for 32-bit vDSO for sparcon 64-bit kernel.vDSO
vDSO for sparcFollowing patch is based on work done by Nick Alcock on 64-bit vDSO for sparcin Oracle linux. I have extended it to include support for 32-bit vDSO for sparcon 64-bit kernel.vDSO for sparc is based on the X86 implementation. This patchprovides vDSO support for both 64-bit and 32-bit programs on 64-bit kernel.vDSO will be disabled on 32-bit linux kernel on sparc.*) vclock_gettime.c contains all the vdso functions. Since data page is mapped before the vdso code page, the pointer to data page is got by subracting offset from an address in the vdso code page. The return address stored in %i7 is used for this purpose.*) During compilation, both 32-bit and 64-bit vdso images are compiled and are converted into raw bytes by vdso2c program to be ready for mapping into the process. 32-bit images are compiled only if CONFIG_COMPAT is enabled. vdso2c generates two files vdso-image-64.c and vdso-image-32.c which contains the respective vDSO image in C structure.*) During vdso initialization, required number of vdso pages are allocated and raw bytes are copied 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 generatedvdso(64/32).so in the source.Testing:========[root@localhost ~]# cat vdso_test.cint 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_fixStart sec: 1502396130End sec : 150239614010000000 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_fixStart sec: 1502396168End sec : 150239616910000000 cycles in 798141262 ns = 79.814126 ns/cycle[root@localhost ~]# cc vdso_test.c -o t64_without_fix -m64 -lrt[root@localhost ~]# ./t64_without_fixStart sec: 1502396208End sec : 150239621810000000 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_fixStart sec: 1502396257End sec : 150239625710000000 cycles in 380984048 ns = 38.098405 ns/cycleV1 to V2 Changes:================= Added hot patching code to switch the read stick instruction to readtick instruction based on the hardware.V2 to V3 Changes:================= Merged latest changes from sparc-next and moved the initializationof clocksource_tick.archdata.vclock_mode to time_init_early. Disabledqueued spinlock and rwlock configuration when simulating 32-bit configto compile 32-bit VDSO.V3 to V4 Changes:================= Hardcoded the page size as 8192 in linker script for both 64-bit and32-bit binaries. Removed unused variables in vdso2c.h. Added -mv8plus flag toMakefile to prevent the generation of relocation entries for __lshrdi3 in 32-bitvdso 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>