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2019-09-20Merge tag 'kbuild-v5.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - add modpost warn exported symbols marked as 'static' because 'static' and EXPORT_SYMBOL is an odd combination - break the build early if gold linker is used - optimize the Bison rule to produce .c and .h files by a single pattern rule - handle PREEMPT_RT in the module vermagic and UTS_VERSION - warn CONFIG options leaked to the user-space except existing ones - make single targets work properly - rebuild modules when module linker scripts are updated - split the module final link stage into scripts/Makefile.modfinal - fix the missed error code in merge_config.sh - improve the error message displayed on the attempt of the O= build in unclean source tree - remove 'clean-dirs' syntax - disable -Wimplicit-fallthrough warning for Clang - add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC - remove ARCH_{CPP,A,C}FLAGS variables - add $(BASH) to run bash scripts - change *CFLAGS_<basetarget>.o to take the relative path to $(obj) instead of the basename - stop suppressing Clang's -Wunused-function warnings when W=1 - fix linux/export.h to avoid genksyms calculating CRC of trimmed exported symbols - misc cleanups * tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits) genksyms: convert to SPDX License Identifier for lex.l and parse.y modpost: use __section in the output to *.mod.c modpost: use MODULE_INFO() for __module_depends export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols export.h: remove defined(__KERNEL__), which is no longer needed kbuild: allow Clang to find unused static inline functions for W=1 build kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN kbuild: refactor scripts/Makefile.extrawarn merge_config.sh: ignore unwanted grep errors kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj) modpost: add NOFAIL to strndup modpost: add guid_t type definition kbuild: add $(BASH) to run scripts with bash-extension kbuild: remove ARCH_{CPP,A,C}FLAGS kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC kbuild: Do not enable -Wimplicit-fallthrough for clang for now kbuild: clean up subdir-ymn calculation in Makefile.clean kbuild: remove unneeded '+' marker from cmd_clean kbuild: remove clean-dirs syntax kbuild: check clean srctree even earlier ...
2019-09-04kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)Masahiro Yamada
Kbuild provides per-file compiler flag addition/removal: CFLAGS_<basetarget>.o CFLAGS_REMOVE_<basetarget>.o AFLAGS_<basetarget>.o AFLAGS_REMOVE_<basetarget>.o CPPFLAGS_<basetarget>.lds HOSTCFLAGS_<basetarget>.o HOSTCXXFLAGS_<basetarget>.o The <basetarget> is the filename of the target with its directory and suffix stripped. This syntax comes into a trouble when two files with the same basename appear in one Makefile, for example: obj-y += foo.o obj-y += dir/foo.o CFLAGS_foo.o := <some-flags> Here, the <some-flags> applies to both foo.o and dir/foo.o The real world problem is: scripts/kconfig/util.c scripts/kconfig/lxdialog/util.c Both files are compiled into scripts/kconfig/mconf, but only the latter should be given with the ncurses flags. It is more sensible to use the relative path to the Makefile, like this: obj-y += foo.o CFLAGS_foo.o := <some-flags> obj-y += dir/foo.o CFLAGS_dir/foo.o := <other-flags> At first, I attempted to replace $(basetarget) with $*. The $* variable is replaced with the stem ('%') part in a pattern rule. This works with most of cases, but does not for explicit rules. For example, arch/ia64/lib/Makefile reuses rule_as_o_S in its own explicit rules, so $* will be empty, resulting in ignoring the per-file AFLAGS. I introduced a new variable, target-stem, which can be used also from explicit rules. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Marc Zyngier <maz@kernel.org>
2019-08-23clocksource/drivers/hyperv: Allocate Hyper-V TSC page staticallyTianyu Lan
Prepare to add Hyper-V sched clock callback and move Hyper-V Reference TSC initialization much earlier in the boot process. Earlier initialization is needed so that it happens while the timestamp value is still 0 and no discontinuity in the timestamp will occur when pv_ops.time.sched_clock calculates its offset. The earlier initialization requires that the Hyper-V TSC page be allocated statically instead of with vmalloc(), so fixup the references to the TSC page and the method of getting its physical address. Signed-off-by: Tianyu Lan <Tianyu.Lan@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lkml.kernel.org/r/20190814123216.32245-2-Tianyu.Lan@microsoft.com
2019-07-20Merge tag 'kbuild-v5.3-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - match the directory structure of the linux-libc-dev package to that of Debian-based distributions - fix incorrect include/config/auto.conf generation when Kconfig creates it along with the .config file - remove misleading $(AS) from documents - clean up precious tag files by distclean instead of mrproper - add a new coccinelle patch for devm_platform_ioremap_resource migration - refactor module-related scripts to read modules.order instead of $(MODVERDIR)/*.mod files to get the list of created modules - remove MODVERDIR - update list of header compile-test - add -fcf-protection=none flag to avoid conflict with the retpoline flags when CONFIG_RETPOLINE=y - misc cleanups * tag 'kbuild-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) kbuild: add -fcf-protection=none when using retpoline flags kbuild: update compile-test header list for v5.3-rc1 kbuild: split out *.mod out of {single,multi}-used-m rules kbuild: remove 'prepare1' target kbuild: remove the first line of *.mod files kbuild: create *.mod with full directory path and remove MODVERDIR kbuild: export_report: read modules.order instead of .tmp_versions/*.mod kbuild: modpost: read modules.order instead of $(MODVERDIR)/*.mod kbuild: modsign: read modules.order instead of $(MODVERDIR)/*.mod kbuild: modinst: read modules.order instead of $(MODVERDIR)/*.mod scsi: remove pointless $(MODVERDIR)/$(obj)/53c700.ver kbuild: remove duplication from modules.order in sub-directories kbuild: get rid of kernel/ prefix from in-tree modules.{order,builtin} kbuild: do not create empty modules.order in the prepare stage coccinelle: api: add devm_platform_ioremap_resource script kbuild: compile-test headers listed in header-test-m as well kbuild: remove unused hostcc-option kbuild: remove tag files by distclean instead of mrproper kbuild: add --hash-style= and --build-id unconditionally kbuild: get rid of misleading $(AS) from documents ...
2019-07-18proc/sysctl: add shared variables for range checkMatteo Croce
In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-17kbuild: add --hash-style= and --build-id unconditionallyMasahiro Yamada
As commit 1e0221374e30 ("mips: vdso: drop unnecessary cc-ldoption") explained, these flags are supported by the minimal required version of binutils. They are supported by ld.lld too. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2019-07-12x86/vdso: Fix flip/flop vdso build bugNaohiro Aota
Two consecutive "make" on an already compiled kernel tree will show different behavior: $ make CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh DESCEND objtool CHK include/generated/compile.h VDSOCHK arch/x86/entry/vdso/vdso64.so.dbg VDSOCHK arch/x86/entry/vdso/vdso32.so.dbg Kernel: arch/x86/boot/bzImage is ready (#3) Building modules, stage 2. MODPOST 12 modules $ make make CALL scripts/checksyscalls.sh CALL scripts/atomic/check-atomics.sh DESCEND objtool CHK include/generated/compile.h VDSO arch/x86/entry/vdso/vdso64.so.dbg OBJCOPY arch/x86/entry/vdso/vdso64.so VDSO2C arch/x86/entry/vdso/vdso-image-64.c CC arch/x86/entry/vdso/vdso-image-64.o VDSO arch/x86/entry/vdso/vdso32.so.dbg OBJCOPY arch/x86/entry/vdso/vdso32.so VDSO2C arch/x86/entry/vdso/vdso-image-32.c CC arch/x86/entry/vdso/vdso-image-32.o AR arch/x86/entry/vdso/built-in.a AR arch/x86/entry/built-in.a AR arch/x86/built-in.a GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o AR init/built-in.a LD vmlinux.o <snip> This is causing "LD vmlinux" once every two times even without any modifications. This is the same bug fixed in commit 92a4728608a8 ("x86/boot: Fix if_changed build flip/flop bug"). Two "if_changed" cannot be used in one target. Fix this merging two commands into one function. Fixes: 7ac870747988 ("x86/vdso: Switch to generic vDSO implementation") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Link: https://lkml.kernel.org/r/20190712101556.17833-1-naohiro.aota@wdc.com
2019-07-03clocksource/drivers: Continue making Hyper-V clocksource ISA agnosticMichael Kelley
Continue consolidating Hyper-V clock and timer code into an ISA independent Hyper-V clocksource driver. Move the existing clocksource code under drivers/hv and arch/x86 to the new clocksource driver while separating out the ISA dependencies. Update Hyper-V initialization to call initialization and cleanup routines since the Hyper-V synthetic clock is not independently enumerated in ACPI. Update Hyper-V clocksource users in KVM and VDSO to get definitions from the new include file. No behavior is changed and no new functionality is added. Suggested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: "bp@alien8.de" <bp@alien8.de> Cc: "will.deacon@arm.com" <will.deacon@arm.com> Cc: "catalin.marinas@arm.com" <catalin.marinas@arm.com> Cc: "mark.rutland@arm.com" <mark.rutland@arm.com> Cc: "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org> Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org> Cc: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org> Cc: "olaf@aepfle.de" <olaf@aepfle.de> Cc: "apw@canonical.com" <apw@canonical.com> Cc: "jasowang@redhat.com" <jasowang@redhat.com> Cc: "marcelo.cerri@canonical.com" <marcelo.cerri@canonical.com> Cc: Sunil Muthuswamy <sunilmut@microsoft.com> Cc: KY Srinivasan <kys@microsoft.com> Cc: "sashal@kernel.org" <sashal@kernel.org> Cc: "vincenzo.frascino@arm.com" <vincenzo.frascino@arm.com> Cc: "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org> Cc: "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org> Cc: "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org> Cc: "arnd@arndb.de" <arnd@arndb.de> Cc: "linux@armlinux.org.uk" <linux@armlinux.org.uk> Cc: "ralf@linux-mips.org" <ralf@linux-mips.org> Cc: "paul.burton@mips.com" <paul.burton@mips.com> Cc: "daniel.lezcano@linaro.org" <daniel.lezcano@linaro.org> Cc: "salyzyn@android.com" <salyzyn@android.com> Cc: "pcc@google.com" <pcc@google.com> Cc: "shuah@kernel.org" <shuah@kernel.org> Cc: "0x7f454c46@gmail.com" <0x7f454c46@gmail.com> Cc: "linux@rasmusvillemoes.dk" <linux@rasmusvillemoes.dk> Cc: "huw@codeweavers.com" <huw@codeweavers.com> Cc: "sfr@canb.auug.org.au" <sfr@canb.auug.org.au> Cc: "pbonzini@redhat.com" <pbonzini@redhat.com> Cc: "rkrcmar@redhat.com" <rkrcmar@redhat.com> Cc: "kvm@vger.kernel.org" <kvm@vger.kernel.org> Link: https://lkml.kernel.org/r/1561955054-1838-3-git-send-email-mikelley@microsoft.com
2019-06-22x86/vdso: Add clock_gettime64() entry pointVincenzo Frascino
Linux 5.1 gained the new clock_gettime64() syscall to address the Y2038 problem on 32bit systems. The x86 VDSO is missing support for this variant of clock_gettime(). Update the x86 specific vDSO library accordingly so it exposes the new time getter. [ tglx: Massaged changelog ] Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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> Cc: Shijith Thotton <sthotton@marvell.com> Cc: Andre Przywara <andre.przywara@arm.com> Link: https://lkml.kernel.org/r/20190621095252.32307-25-vincenzo.frascino@arm.com
2019-06-22x86/vdso: Add clock_getres() entry pointVincenzo Frascino
The generic vDSO library provides an implementation of clock_getres() that can be leveraged by each architecture. Add the clock_getres() VDSO entry point on x86. [ tglx: Massaged changelog and cleaned up the function signature formatting ] Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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> Cc: Shijith Thotton <sthotton@marvell.com> Cc: Andre Przywara <andre.przywara@arm.com> Link: https://lkml.kernel.org/r/20190621095252.32307-24-vincenzo.frascino@arm.com
2019-06-22x86/vdso: Switch to generic vDSO implementationVincenzo Frascino
The x86 vDSO library requires some adaptations to take advantage of the newly introduced generic vDSO library. Introduce the following changes: - Modification of vdso.c to be compliant with the common vdso datapage - Use of lib/vdso for gettimeofday [ tglx: Massaged changelog and cleaned up the function signature formatting ] Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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> Cc: Shijith Thotton <sthotton@marvell.com> Cc: Andre Przywara <andre.przywara@arm.com> Link: https://lkml.kernel.org/r/20190621095252.32307-23-vincenzo.frascino@arm.com
2019-06-21x86/vdso: Prevent segfaults due to hoisted vclock readsAndy Lutomirski
GCC 5.5.0 sometimes cleverly hoists reads of the pvclock and/or hvclock pages before the vclock mode checks. This creates a path through vclock_gettime() in which no vclock is enabled at all (due to disabled TSC on old CPUs, for example) but the pvclock or hvclock page nevertheless read. This will segfault on bare metal. This fixes commit 459e3a21535a ("gcc-9: properly declare the {pv,hv}clock_page storage") in the sense that, before that commit, GCC didn't seem to generate the offending code. There was nothing wrong with that commit per se, and -stable maintainers should backport this to all supported kernels regardless of whether the offending commit was present, since the same crash could just as easily be triggered by the phase of the moon. On GCC 9.1.1, this doesn't seem to affect the generated code at all, so I'm not too concerned about performance regressions from this fix. Cc: stable@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov <bp@alien8.de> Reported-by: Duncan Roe <duncan_roe@optusnet.com.au> Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223Thomas Gleixner
Based on 1 normalized pattern(s): subject to the gnu public license v 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 9 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528171440.130801526@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214Thomas Gleixner
Based on 1 normalized pattern(s): subject to the gpl v 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528171439.372657724@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-08x86/vdso: Remove hpet_page from vDSOJia Zhang
This trivial cleanup finalizes the removal of vDSO HPET support. Fixes: 1ed95e52d902 ("x86/vdso: Remove direct HPET access through the vDSO") Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: luto@kernel.org Cc: bp@alien8.de Link: https://lkml.kernel.org/r/20190401114045.7280-1-zhang.jia@linux.alibaba.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-06Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "This includes the following changes: - cpu_has() cleanups - sync_bitops.h modernization to the rmwcc.h facility, similarly to bitops.h - continued LTO annotations/fixes - misc cleanups and smaller cleanups" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/um/vdso: Drop unnecessary cc-ldoption x86/vdso: Rename variable to fix -Wshadow warning x86/cpu/amd: Exclude 32bit only assembler from 64bit build x86/asm: Mark all top level asm statements as .text x86/build/vdso: Add FORCE to the build rule of %.so x86/asm: Modernize sync_bitops.h x86/mm: Convert some slow-path static_cpu_has() callers to boot_cpu_has() x86: Convert some slow-path static_cpu_has() callers to boot_cpu_has() x86/asm: Clarify static_cpu_has()'s intended use x86/uaccess: Fix implicit cast of __user pointer x86/cpufeature: Remove __pure attribute to _static_cpu_has()
2019-05-01gcc-9: properly declare the {pv,hv}clock_page storageLinus Torvalds
The pvlock_page and hvclock_page variables are (as the name implies) addresses to pages, created by the linker script. But we declared them as just "extern u8" variables, which _works_, but now that gcc does some more bounds checking, it causes warnings like warning: array subscript 1 is outside array bounds of ‘u8[1]’ when we then access more than one byte from those variables. Fix this by simply making the declaration of the variables match reality, which makes the compiler happy too. Signed-off-by: Linus Torvalds <torvalds@-linux-foundation.org>
2019-04-19x86/vdso: Rename variable to fix -Wshadow warningLeonardo Brás
The go32() and go64() functions has an argument and a local variable called ‘name’. Rename both to clarify the code and to fix a warning with -Wshadow. Signed-off-by: Leonardo Brás <leobras.c@gmail.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David.Laight@aculab.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: helen@koikeco.de Cc: linux-kbuild@vger.kernel.org Cc: lkcamp@lists.libreplanetbr.org Link: http://lkml.kernel.org/r/20181023011022.GA6574@WindFlash Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-18x86/build/vdso: Add FORCE to the build rule of %.soMasahiro Yamada
$(call if_changed,...) must have FORCE as a prerequisite. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1554280212-10578-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-26Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kprobes: Remove trampoline_handler() prototype x86/kernel: Fix more -Wmissing-prototypes warnings x86: Fix various typos in comments x86/headers: Fix -Wmissing-prototypes warning x86/process: Avoid unnecessary NULL check in get_wchan() x86/traps: Complete prototype declarations x86/mce: Fix -Wmissing-prototypes warnings x86/gart: Rewrite early_gart_iommu_check() comment
2018-12-26Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "Two changes: - Remove (some) remnants of the vDSO's fake section table mechanism that were left behind when the vDSO build process reverted to using "objdump -S" to strip the userspace image. - Remove hardcoded POPCNT mnemonics now that the minimum binutils version supports the symbolic form" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Remove a stale/misleading comment from the linker script x86/vdso: Remove obsolete "fake section table" reservation x86: Use POPCNT mnemonics in arch_hweight.h
2018-12-15x86/vdso: Pass --eh-frame-hdr to the linkerAlistair Strachan
Commit 379d98ddf413 ("x86: vdso: Use $LD instead of $CC to link") accidentally broke unwinding from userspace, because ld would strip the .eh_frame sections when linking. Originally, the compiler would implicitly add --eh-frame-hdr when invoking the linker, but when this Makefile was converted from invoking ld via the compiler, to invoking it directly (like vmlinux does), the flag was missed. (The EH_FRAME section is important for the VDSO shared libraries, but not for vmlinux.) Fix the problem by explicitly specifying --eh-frame-hdr, which restores parity with the old method. See relevant bug reports for additional info: https://bugzilla.kernel.org/show_bug.cgi?id=201741 https://bugzilla.redhat.com/show_bug.cgi?id=1659295 Fixes: 379d98ddf413 ("x86: vdso: Use $LD instead of $CC to link") Reported-by: Florian Weimer <fweimer@redhat.com> Reported-by: Carlos O'Donell <carlos@redhat.com> Reported-by: "H. J. Lu" <hjl.tools@gmail.com> Signed-off-by: Alistair Strachan <astrachan@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Laura Abbott <labbott@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Carlos O'Donell <carlos@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: kernel-team@android.com Cc: Laura Abbott <labbott@redhat.com> Cc: stable <stable@vger.kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: X86 ML <x86@kernel.org> Link: https://lkml.kernel.org/r/20181214223637.35954-1-astrachan@google.com
2018-12-07x86/vdso: Drop implicit common-page-size linker flagNick Desaulniers
GNU linker's -z common-page-size's default value is based on the target architecture. arch/x86/entry/vdso/Makefile sets it to the architecture default, which is implicit and redundant. Drop it. Fixes: 2aae950b21e4 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu") Reported-by: Dmitry Golovin <dima@golovin.in> Reported-by: Bill Wendling <morbo@google.com> Suggested-by: Dmitry Golovin <dima@golovin.in> Suggested-by: Rui Ueyama <ruiu@google.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Fangrui Song <maskray@google.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20181206191231.192355-1-ndesaulniers@google.com Link: https://bugs.llvm.org/show_bug.cgi?id=38774 Link: https://github.com/ClangBuiltLinux/linux/issues/31
2018-12-05x86/vdso: Remove a stale/misleading comment from the linker scriptSean Christopherson
Once upon a time, vdso2c aggressively stripped data from the vDSO image when generating the final userspace image. This included stripping the .altinstructions and .altinstr_replacement sections. Eventually, the stripping process reverted to "objdump -S" and no longer removed the aforementioned sections, but the comment remained. Keeping the .alt* sections at the end of the PT_LOAD segment is no longer necessary, but there's no harm in doing so and it's a helpful reminder that they don't need to be included in the final vDSO image, i.e. someone may want to take another stab at zapping/stripping the unneeded sections. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: da861e18eccc ("x86, vdso: Get rid of the fake section mechanism") Link: http://lkml.kernel.org/r/20181204212600.28090-3-sean.j.christopherson@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-05x86/vdso: Remove obsolete "fake section table" reservationSean Christopherson
At one point the vDSO image was manually stripped down by vdso2c in an attempt to minimize the size of the image mapped into userspace. Part of that stripping process involved building a fake section table so as not to break userspace processes that parse the section table. Memory for the fake section table was reserved in the .rodata section so that vdso2c could simply copy the entire PT_LOAD segment into the userspace image after building the fake table. Eventually, the entire fake section table approach was dropped in favor of stripping the vdso "the old fashioned way", i.e. via objdump -S. But, the reservation in .rodata for the fake table was left behind. Remove the reserveration along with a few other related defines and section entries. Removing the fake section table placeholder zaps a whopping 0x340 bytes from the 64-bit vDSO image, which drops the current image's size to under 4k, i.e. reduces the effective size of the userspace vDSO mapping by a full page. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: da861e18eccc ("x86, vdso: Get rid of the fake section mechanism") Link: http://lkml.kernel.org/r/20181204212600.28090-2-sean.j.christopherson@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-03x86: Fix various typos in commentsIngo Molnar
Go over arch/x86/ and fix common typos in comments, and a typo in an actual function argument name. No change in functionality intended. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-26x86: convert vdso to use vm_fault_tMatthew Wilcox
Return vm_fault_t codes directly from the appropriate mm routines instead of converting from errnos ourselves. Fixes a minor bug where we'd return SIGBUS instead of the correct OOM code if we ran out of memory allocating page tables. Link: http://lkml.kernel.org/r/20180828145728.11873-5-willy@infradead.org Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-23Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso updates from Ingo Molnar: "Two main changes: - Cleanups, simplifications and CLOCK_TAI support (Thomas Gleixner) - Improve code generation (Andy Lutomirski)" * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Rearrange do_hres() to improve code generation x86/vdso: Document vgtod_ts better x86/vdso: Remove "memory" clobbers in the vDSO syscall fallbacks x66/vdso: Add CLOCK_TAI support x86/vdso: Move cycle_last handling into the caller x86/vdso: Simplify the invalid vclock case x86/vdso: Replace the clockid switch case x86/vdso: Collapse coarse functions x86/vdso: Collapse high resolution functions x86/vdso: Introduce and use vgtod_ts x86/vdso: Use unsigned int consistently for vsyscall_gtod_data:: Seq x86/vdso: Enforce 64bit clocksource x86/time: Implement clocksource_arch_init() clocksource: Provide clocksource_arch_init()
2018-10-08x86/fsgsbase/64: Clean up various detailsIngo Molnar
So: - use 'extern' consistently for APIs - fix weird header guard - clarify code comments - reorder APIs by type Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chang S. Bae <chang.seok.bae@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1537312139-5580-2-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-08x86/segments: Introduce the 'CPUNODE' naming to better document the segment ↵Ingo Molnar
limit CPU/node NR trick We have a special segment descriptor entry in the GDT, whose sole purpose is to encode the CPU and node numbers in its limit (size) field. There are user-space instructions that allow the reading of the limit field, which gives us a really fast way to read the CPU and node IDs from the vDSO for example. But the naming of related functionality does not make this clear, at all: VDSO_CPU_SIZE VDSO_CPU_MASK __CPU_NUMBER_SEG GDT_ENTRY_CPU_NUMBER vdso_encode_cpu_node vdso_read_cpu_node There's a number of problems: - The 'VDSO_CPU_SIZE' doesn't really make it clear that these are number of bits, nor does it make it clear which 'CPU' this refers to, i.e. that this is about a GDT entry whose limit encodes the CPU and node number. - Furthermore, the 'CPU_NUMBER' naming is actively misleading as well, because the segment limit encodes not just the CPU number but the node ID as well ... So use a better nomenclature all around: name everything related to this trick as 'CPUNODE', to make it clear that this is something special, and add _BITS to make it clear that these are number of bits, and propagate this to every affected name: VDSO_CPU_SIZE => VDSO_CPUNODE_BITS VDSO_CPU_MASK => VDSO_CPUNODE_MASK __CPU_NUMBER_SEG => __CPUNODE_SEG GDT_ENTRY_CPU_NUMBER => GDT_ENTRY_CPUNODE vdso_encode_cpu_node => vdso_encode_cpunode vdso_read_cpu_node => vdso_read_cpunode This, beyond being less confusing, also makes it easier to grep for all related functionality: $ git grep -i cpunode arch/x86 Also, while at it, fix "return is not a function" style sloppiness in vdso_encode_cpunode(). Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chang S. Bae <chang.seok.bae@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1537312139-5580-2-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-08x86/vdso: Initialize the CPU/node NR segment descriptor earlierChang S. Bae
Currently the CPU/node NR segment descriptor (GDT_ENTRY_CPU_NUMBER) is initialized relatively late during CPU init, from the vCPU code, which has a number of disadvantages, such as hotplug CPU notifiers and SMP cross-calls. Instead just initialize it much earlier, directly in cpu_init(). This reduces complexity and increases robustness. [ mingo: Wrote new changelog. ] Suggested-by: H. Peter Anvin <hpa@zytor.com> Suggested-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1537312139-5580-9-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-08x86/vdso: Introduce helper functions for CPU and node numberChang S. Bae
Clean up the CPU/node number related code a bit, to make it more apparent how we are encoding/extracting the CPU and node fields from the segment limit. No change in functionality intended. [ mingo: Wrote new changelog. ] Suggested-by: Andy Lutomirski <luto@kernel.org> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Link: http://lkml.kernel.org/r/1537312139-5580-8-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-08x86/segments/64: Rename the GDT PER_CPU entry to CPU_NUMBERChang S. Bae
The old 'per CPU' naming was misleading: 64-bit kernels don't use this GDT entry for per CPU data, but to store the CPU (and node) ID. [ mingo: Wrote new changelog. ] Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Link: http://lkml.kernel.org/r/1537312139-5580-7-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-05x86/vdso: Rearrange do_hres() to improve code generationAndy Lutomirski
vgetcyc() is full of barriers, so fetching values out of the vvar page before vgetcyc() for use after vgetcyc() results in poor code generation. Put vgetcyc() first to avoid this problem. Also, pull the tv_sec division into the loop and put all the ts writes together. The old code wrote ts->tv_sec on each iteration before the syscall fallback check and then added in the offset afterwards, which forced the compiler to pointlessly copy base->sec to ts->tv_sec on each iteration. The new version seems to generate sensible code. Saves several cycles. With this patch applied, the result is faster than before the clock_gettime() rewrite. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/3c05644d010b72216aa286a6d20b5078d5fae5cd.1538762487.git.luto@kernel.org
2018-10-05x86/vdso: Remove "memory" clobbers in the vDSO syscall fallbacksAndy Lutomirski
When a vDSO clock function falls back to the syscall, no special barriers or ordering is needed, and the syscall fallbacks don't clobber any memory that is not explicitly listed in the asm constraints. Remove the "memory" clobber. This causes minor changes to the generated code, but otherwise has no obvious performance impact. I think it's nice to have, though, since it may help the optimizer in the future. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/3a7438f5fb2422ed881683d2ccffd7f987b2dc44.1538689401.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-04x86/vdso: Move cycle_last handling into the callerThomas Gleixner
Dereferencing gtod->cycle_last all over the place and foing the cycles < last comparison in the vclock read functions generates horrible code. Doing it at the call site is much better and gains a few cycles both for TSC and pvclock. Caveat: This adds the comparison to the hyperv vclock as well, but I have no way to test that. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Cc: virtualization@lists.linux-foundation.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20180917130707.741440803@linutronix.de
2018-10-04x86/vdso: Simplify the invalid vclock caseThomas Gleixner
The code flow for the vclocks is convoluted as it requires the vclocks which can be invalidated separately from the vsyscall_gtod_data sequence to store the fact in a separate variable. That's inefficient. Restructure the code so the vclock readout returns cycles and the conversion to nanoseconds is handled at the call site. If the clock gets invalidated or vclock is already VCLOCK_NONE, return U64_MAX as the cycle value, which is invalid for all clocks and leave the sequence loop immediately in that case by calling the fallback function directly. This allows to remove the gettimeofday fallback as it now uses the clock_gettime() fallback and does the nanoseconds to microseconds conversion in the same way as it does when the vclock is functional. It does not make a difference whether the division by 1000 happens in the kernel fallback or in userspace. Generates way better code and gains a few cycles back. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Cc: virtualization@lists.linux-foundation.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20180917130707.657928937@linutronix.de
2018-10-04x86/vdso: Replace the clockid switch caseThomas Gleixner
Now that the time getter functions use the clockid as index into the storage array for the base time access, the switch case can be replaced. - Check for clockid >= MAX_CLOCKS and for negative clockid (CPU/FD) first and call the fallback function right away. - After establishing that clockid is < MAX_CLOCKS, convert the clockid to a bitmask - Check for the supported high resolution and coarse functions by anding the bitmask of supported clocks and check whether a bit is set. This completely avoids jump tables, reduces the number of conditionals and makes the VDSO extensible for other clock ids. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Cc: virtualization@lists.linux-foundation.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20180917130707.574315796@linutronix.de
2018-10-04x86/vdso: Collapse coarse functionsThomas Gleixner
do_realtime_coarse() and do_monotonic_coarse() are now the same except for the storage array index. Hand the index in as an argument and collapse the functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Cc: virtualization@lists.linux-foundation.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20180917130707.490733779@linutronix.de
2018-10-04x86/vdso: Collapse high resolution functionsThomas Gleixner
do_realtime() and do_monotonic() are now the same except for the storage array index. Hand the index in as an argument and collapse the functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.s