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path: root/include/asm-x86_64/vsyscall.h
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2007-07-21x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpuAndi Kleen
This implements new vDSO for x86-64. The concept is similar to the existing vDSOs on i386 and PPC. x86-64 has had static vsyscalls before, but these are not flexible enough anymore. A vDSO is a ELF shared library supplied by the kernel that is mapped into user address space. The vDSO mapping is randomized for each process for security reasons. Doing this was needed for clock_gettime, because clock_gettime always needs a syscall fallback and having one at a fixed address would have made buffer overflow exploits too easy to write. The vdso can be disabled with vdso=0 It currently includes a new gettimeofday implemention and optimized clock_gettime(). The gettimeofday implementation is slightly faster than the one in the old vsyscall. clock_gettime is significantly faster than the syscall for CLOCK_MONOTONIC and CLOCK_REALTIME. The new calls are generally faster than the old vsyscall. Advantages over the old x86-64 vsyscalls: - Extensible - Randomized - Cleaner - Easier to virtualize (the old static address range previously causes overhead e.g. for Xen because it has to create special page tables for it) Weak points: - glibc support still to be written The VM interface is partly based on Ingo Molnar's i386 version. Includes compile fix from Joachim Deguara Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16[PATCH] time: x86_64: re-enable vsyscall support for x86_64john stultz
Cleanup and re-enable vsyscall gettimeofday using the generic clocksource infrastructure. [akpm@osdl.org: cleanup] Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andi Kleen <ak@muc.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-13[PATCH] x86-64: get rid of ARCH_HAVE_XTIME_LOCKEric Dumazet
ARCH_HAVE_XTIME_LOCK is used by x86_64 arch . This arch needs to place a read only copy of xtime_lock into vsyscall page. This read only copy is named __xtime_lock, and xtime_lock is defined in arch/x86_64/kernel/vmlinux.lds.S as an alias. So the declaration of xtime_lock in kernel/timer.c was guarded by ARCH_HAVE_XTIME_LOCK define, defined to true on x86_64. We can get same result with _attribute__((weak)) in the declaration. linker should do the job. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-12-07[PATCH] x86-64: fix perms/range of vsyscall vma in /proc/*/mapsErnie Petrides
The final line of /proc/<pid>/maps on x86_64 for native 64-bit tasks shows an incorrect ending address and incorrect permissions. There is only a single page mapped in this vsyscall region, and it is accessible for both read and execute. The patch below fixes this. (Since 32-bit-compat tasks have a real vma with correct perms/range, no change is necessary for that scenario.) Before the patch, a "cat /proc/self/maps | tail -1" shows this: ffffffffff600000-ffffffffffe00000 ---p 00000000 [...] After the patch, this is the output: ffffffffff600000-ffffffffff601000 r-xp 00000000 [...] Signed-off-by: Ernie Petrides <petrides@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de>
2006-11-14[PATCH] x86-64: Fix vgetcpu when CONFIG_HOTPLUG_CPU is disabledAndi Kleen
The vgetcpu per CPU initialization previously relied on CPU hotplug events for all CPUs to initialize the per CPU state. That only worked only on kernels with CONFIG_HOTPLUG_CPU enabled. On the others some CPUs didn't get their state initialized properly and vgetcpu wouldn't work. Change the initialization sequence to instead run in a normal initcall (which runs after the normal CPU bootup) and initialize all running CPUs there. Later hotplug CPUs are still handled with an hotplug notifier. This actually simplifies the code somewhat. Signed-off-by: Andi Kleen <ak@suse.de>
2006-10-01[PATCH] kill wall_jiffiesAtsushi Nemoto
With 2.6.18-rc4-mm2, now wall_jiffies will always be the same as jiffies. So we can kill wall_jiffies completely. This is just a cleanup and logically should not change any real behavior except for one thing: RTC updating code in (old) ppc and xtensa use a condition "jiffies - wall_jiffies == 1". This condition is never met so I suppose it is just a bug. I just remove that condition only instead of kill the whole "if" block. [heiko.carstens@de.ibm.com: s390 build fix and cleanup] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] Add the vgetcpu vsyscallVojtech Pavlik
This patch adds a vgetcpu vsyscall, which depending on the CPU RDTSCP capability uses either the RDTSCP or CPUID to obtain a CPU and node numbers and pass them to the program. AK: Lots of changes over Vojtech's original code: Better prototype for vgetcpu() It's better to pass the cpu / node numbers as separate arguments to avoid mistakes when going from SMP to NUMA. Also add a fast time stamp based cache using a user supplied argument to speed things more up. Use fast method from Chuck Ebbert to retrieve node/cpu from GDT limit instead of CPUID Made sure RDTSCP init is always executed after node is known. Drop printk Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-16[PATCH] Fix 'make headers_check' on x86_64David Woodhouse
On Tue, 2006-09-12 at 17:44 +0100, David Woodhouse wrote: > asm-x86_64/elf.h requires asm/processor.h, which does not exist > asm-x86_64/signal.h requires linux/linkage.h, which does not exist > asm-x86_64/unistd.h requires linux/linkage.h, which does not exist > asm-x86_64/vsyscall.h requires linux/seqlock.h, which does not exist Again, move stuff which shouldn't be visible inside (mostly already existing) #ifdef __KERNEL__. This fixes a bunch of mislabelled and unlabelled #endifs in unistd.h and also cleans that up to conform with what's visible on other architectures, since the minimal fix for the error reported about would have involved a more intrusive patch, renesting other ifdefs. Signed-off-by: David Woodhouse <dwmw2@infradead.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11[PATCH] x86_64: sparse warning cleanupsStephen Hemminger
Fix some trivial sparse warnings in x86_64 code. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12[PATCH] x86-64: Remove unused vxtime.hz fieldAndi Kleen
Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17[PATCH] x86_64: Add pmtimer supportAndi Kleen
There are unfortunately more and more multi processor Opteron systems which don't have HPET timer support in the southbridge. This covers in particular Nvidia and VIA chipsets. They also don't guarantee that the TSCs are synchronized between CPUs; and especially with MP powernow the systems are nearly unusable because the time gets very inconsistent between CPUs. The timer code for x86-64 was originally written under the assumption that we could fall back to the HPET timer on such systems. But this doesn't work there. Another alternative is to use the ACPI PM timer as primary time source. This patch does that. The kernel only uses PM timer when there is no other choice because it has some disadvantages. Ported over from i386. It should be faster than the i386 version because I dropped the "read three times" workaround, but is still considerable slower than HPET and also does not work together with vsyscalls which have to be disabled. Cc: <mark.langsdorf@amd.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!