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2011-10-28Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, amd: Include linux/elf.h since we use stuff from asm/elf.h x86: cache_info: Update calculation of AMD L3 cache indices x86: cache_info: Kill the atomic allocation in amd_init_l3_cache() x86: cache_info: Kill the moronic shadow struct x86: cache_info: Remove bogus free of amd_l3_cache data x86, amd: Include elf.h explicitly, prepare the code for the module.h split x86-32, amd: Move va_align definition to unbreak 32-bit build x86, amd: Move BSP code to cpu_dev helper x86: Add a BSP cpu_dev helper x86, amd: Avoid cache aliasing penalties on AMD family 15h
2011-08-23Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-32, vdso: On system call restart after SYSENTER, use int $0x80 x86, UV: Remove UV delay in starting slave cpus x86, olpc: Wait for last byte of EC command to be accepted
2011-08-23x86-32, vdso: On system call restart after SYSENTER, use int $0x80H. Peter Anvin
When we enter a 32-bit system call via SYSENTER or SYSCALL, we shuffle the arguments to match the int $0x80 calling convention. This was probably a design mistake, but it's what it is now. This causes errors if the system call as to be restarted. For SYSENTER, we have to invoke the instruction from the vdso as the return address is hardcoded. Accordingly, we can simply replace the jump in the vdso with an int $0x80 instruction and use the slower entry point for a post-restart. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/CA%2B55aFztZ=r5wa0x26KJQxvZOaQq8s2v3u50wCyJcA-Sc4g8gQ@mail.gmail.com Cc: <stable@kernel.org>
2011-08-05x86, amd: Avoid cache aliasing penalties on AMD family 15hBorislav Petkov
This patch provides performance tuning for the "Bulldozer" CPU. With its shared instruction cache there is a chance of generating an excessive number of cache cross-invalidates when running specific workloads on the cores of a compute module. This excessive amount of cross-invalidations can be observed if cache lines backed by shared physical memory alias in bits [14:12] of their virtual addresses, as those bits are used for the index generation. This patch addresses the issue by clearing all the bits in the [14:12] slice of the file mapping's virtual address at generation time, thus forcing those bits the same for all mappings of a single shared library across processes and, in doing so, avoids instruction cache aliases. It also adds the command line option "align_va_addr=(32|64|on|off)" with which virtual address alignment can be enabled for 32-bit or 64-bit x86 individually, or both, or be completely disabled. This change leaves virtual region address allocation on other families and/or vendors unaffected. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1312550110-24160-2-git-send-email-bp@amd64.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-04x86-64: Pad vDSO to a page boundaryAndy Lutomirski
This avoids an information leak to userspace. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/a63380a3c58a0506a2f5a18ba1b12dbde1f25e58.1312378163.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-21x86-64, vdso: Do not allocate memory for the vDSOAndy Lutomirski
We can map the vDSO straight from kernel data, saving a few page allocations. As an added bonus, the deleted code contained a memory leak. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/2c4ed5c2c2e93603790229e0c3403ae506ccc0cb.1311277573.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2011-07-18x86, vdso: Drop now wrong commentBorislav Petkov
Now that 1b3f2a72bbcfdf92e368a44448c45eb639b05b5e is in, it is very important that the below lying comment be removed! :-) Signed-off-by: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20110718191054.GA18359@liondog.tnic Acked-by: Andy Lutomirski <luto@mit.edu> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-14x86-64: Move vread_tsc and vread_hpet into the vDSOAndy Lutomirski
The vsyscall page now consists entirely of trap instructions. Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13x86-64: Add --no-undefined to vDSO buildAndy Lutomirski
This gives much nicer diagnostics when something goes wrong. It's supported at least as far back as binutils 2.15. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/de0b50920469ff6359c529526e7639fdd36fa83c.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13x86-64: Allow alternative patching in the vDSOAndy Lutomirski
This code is short enough and different enough from the module loader that it's not worth trying to share anything. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/e73112e4381fff29e31b882c2d0856822edaea53.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-06-05x86-64: Remove kernel.vsyscall64 sysctlAndy Lutomirski
It's unnecessary overhead in code that's supposed to be highly optimized. Removing it allows us to remove one of the two syscall instructions in the vsyscall page. The only sensible use for it is for UML users, and it doesn't fully address inconsistent vsyscall results on UML. The real fix for UML is to stop using vsyscalls entirely. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Jesper Juhl <jj@chaosbits.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: richard -rw- weinberger <richard.weinberger@gmail.com> Cc: Mikael Pettersson <mikpe@it.uu.se> Cc: Andi Kleen <andi@firstfloor.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Louis Rilling <Louis.Rilling@kerlabs.com> Cc: Valdis.Kletnieks@vt.edu Cc: pageexec@freemail.hu Link: http://lkml.kernel.org/r/973ae803fe76f712da4b2740e66dccf452d3b1e4.1307292171.git.luto@mit.edu Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-26x86: vdso: Remove unused variableThomas Gleixner
Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@mit.edu>
2011-05-24x86-64: Optimize vDSO time()Andy Lutomirski
This function just reads a 64-bit variable that's updated atomically, so we don't need any locks. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C40e2700f8cda4d511e5910be1e633025d28b36c2.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-24x86-64: Add time to vDSOAndy Lutomirski
The only fast implementation of time(2) we expose is through the vsyscall page and we want to get userspace to stop using the vsyscall page. So make it available through the vDSO as well. This is essentially a cut-n-paste job. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3Cbf963bac5207de4b29613f27c42705e4371812a8.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-24x86-64: Turn off -pg and turn on -foptimize-sibling-calls for vDSOAndy Lutomirski
The vDSO isn't part of the kernel, so profiling and kernel backtraces don't really matter. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C23087b738c037342abb53f2f07b9bef89ceaeea3.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-24x86-64: Vclock_gettime(CLOCK_MONOTONIC) can't ever see nsec < 0Andy Lutomirski
vclock_gettime's do_monotonic helper can't ever generate a negative nsec value, so it doesn't need to check whether it's negative. In the CLOCK_MONOTONIC_COARSE case, ns can't ever exceed 2e9-1, so we can avoid the loop entirely. This saves a single easily-predicted branch. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3Cd6d528d32c7a21618057cfc9005942a0fe5cb54a.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-05-24x86-64: Clean up vdso/kernel shared variablesAndy Lutomirski
Variables that are shared between the vdso and the kernel are currently a bit of a mess. They are each defined with their own magic, they are accessed differently in the kernel, the vsyscall page, and the vdso, and one of them (vsyscall_clock) doesn't even really exist. This changes them all to use a common mechanism. All of them are delcared in vvar.h with a fixed address (validated by the linker script). In the kernel (as before), they look like ordinary read-write variables. In the vsyscall page and the vdso, they are accessed through a new macro VVAR, which gives read-only access. The vdso is now loaded verbatim into memory without any fixups. As a side bonus, access from the vdso is faster because a level of indirection is removed. While we're at it, pack jiffies and vgetcpu_mode into the same cacheline. Signed-off-by: Andy Lutomirski <luto@mit.edu> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Borislav Petkov <bp@amd64.org> Link: http://lkml.kernel.org/r/%3C7357882fbb51fa30491636a7b6528747301b7ee9.1306156808.git.luto%40mit.edu%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-23mm: arch: rename in_gate_area_no_task to in_gate_area_no_mmStephen Wilson
Now that gate vma's are referenced with respect to a particular mm and not a particular task it only makes sense to propagate the change to this predicate as well. Signed-off-by: Stephen Wilson <wilsons@start.ca> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-23mm: arch: make in_gate_area take an mm_struct instead of a task_structStephen Wilson
Morally, the question of whether an address lies in a gate vma should be asked with respect to an mm, not a particular task. Moreover, dropping the dependency on task_struct will help make existing and future operations on mm's more flexible and convenient. Signed-off-by: Stephen Wilson <wilsons@start.ca> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-23mm: arch: make get_gate_vma take an mm_struct instead of a task_structStephen Wilson
Morally, the presence of a gate vma is more an attribute of a particular mm than a particular task. Moreover, dropping the dependency on task_struct will help make both existing and future operations on mm's more flexible and convenient. Signed-off-by: Stephen Wilson <wilsons@start.ca> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-12-13x86, gcc-4.6: Use gcc -m options when building vdsoH. Peter Anvin
The vdso Makefile passes linker-style -m options not to the linker but to gcc. This happens to work with earlier gcc, but fails with gcc 4.6. Pass gcc-style -m options, instead. Note: all currently supported versions of gcc supports -m32, so there is no reason to conditionalize it any more. Reported-by: H. J. Lu <hjl.tools@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> LKML-Reference: <tip-*@git.kernel.org> Cc: <stable@kernel.org>
2010-08-06Merge branches 'x86-cleanups-for-linus', 'x86-vmware-for-linus', ↵Linus Torvalds
'x86-mtrr-for-linus', 'x86-apic-for-linus', 'x86-fpu-for-linus' and 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Clean up arch/x86/kernel/cpu/mtrr/cleanup.c: use ";" not "," to terminate statements * 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, vmware: Preset lpj values when on VMware. * 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, mtrr: Use stop machine context to rendezvous all the cpu's * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86/apic/es7000_32: Remove unused variable * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Avoid unnecessary __clear_user() and xrstor in signal handling * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, vdso: Unmap vdso pages
2010-08-06Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Ioremap: fix wrong physical address handling in PAT code x86, tlb: Clean up and correct used type x86, iomap: Fix wrong page aligned size calculation in ioremapping code x86, mm: Create symbolic index into address_markers array x86, ioremap: Fix normal ram range check x86, ioremap: Fix incorrect physical address handling in PAE mode x86-64, mm: Initialize VDSO earlier on 64 bits x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages
2010-08-02x86, vdso: Unmap vdso pagesShaohua Li
We mapped vdso pages but never unmapped them and the virtual address is lost after exiting from the function, so unmap vdso pages here. Signed-off-by: Shaohua Li <shaohua.li@intel.com> LKML-Reference: <20100802004934.GA2505@sli10-desk.sh.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-07-27x86, vdso: Don't quote $nm in the script for checking vdso referencesH. Peter Anvin
Don't quote $nm in the script for checking the vdso for external references. Doing so breaks multiword constructs, like using CROSS_COMPILE='ccache '. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <20100728134252.2e4c27cf.sfr@canb.auug.org.au>
2010-06-18x86, vdso: Error out if the vdso contains external referencesH. Peter Anvin
The vdso is a piece of userspace code which is supposed to be fully self-contained. Any external (undefined) reference is an error, and should be caught at compile time. This was giving us trouble when compiling with -Os on gcc 4.5.0, for example (failed inline). The need to do a buildtime check was pointed out by Andi Kleen. Reported-by: Andi Kleen <andi@firstfloor.org> LKML-Reference: <tip-*@vger.kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-06-18x86-64, mm: Initialize VDSO earlier on 64 bitsJiri Slaby
When initrd is in use and a driver does request_module() in its module_init (i.e. __initcall or device_initcall), a modprobe process is created with VDSO mapping. But VDSO is inited even in __initcall, i.e. on the same level (at the same time), so it may not be inited yet (link order matters). Move the VDSO initialization code earlier by switching to something before rootfs_initcall where initrd is loaded as rootfs. Specifically to subsys_initcall. Do it for standard 64-bit path (init_vdso_vars) and for compat (sysenter_setup), just in case people have 32-bit initrd and ia32 emulation built-in. i386 (pure 32-bit) is not affected, since sysenter_setup() is called from check_bugs()->identify_boot_cpu() in start_kernel() before rest_init()->kernel_thread(kernel_init) where even kernel_init() calls do_basic_setup()->do_initcalls(). What this patch fixes are early modprobe crashes such as: Unpacking initramfs... Freeing initrd memory: 9324k freed modprobe[368]: segfault at 7fff4429c020 ip 00007fef397e160c \ sp 00007fff442795c0 error 4 in ld-2.11.2.so[7fef397df000+1f000] Signed-off-by: Jiri Slaby <jslaby@suse.cz> LKML-Reference: <1276720242-13365-1-git-send-email-jslaby@suse.cz> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-11-12sysctl x86: Remove dead binary sysctl supportEric W. Biederman
Now that sys_sysctl is a generic wrapper around /proc/sys .ctl_name and .strategy members of sysctl tables are dead code. Remove them. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-09-20kbuild: rename ld-option to cc-ldoptionSam Ravnborg
ld-option is misnamed as it test options to gcc, not to ld. Renamed it to reflect this. Cc: Andi Kleen <andi@firstfloor.org> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2009-08-21time: Introduce CLOCK_REALTIME_COARSEjohn stultz
After talking with some application writers who want very fast, but not fine-grained timestamps, I decided to try to implement new clock_ids to clock_gettime(): CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE which returns the time at the last tick. This is very fast as we don't have to access any hardware (which can be very painful if you're using something like the acpi_pm clocksource), and we can even use the vdso clock_gettime() method to avoid the syscall. The only trade off is you only get low-res tick grained time resolution. This isn't a new idea, I know Ingo has a patch in the -rt tree that made the vsyscall gettimeofday() return coarse grained time when the vsyscall64 sysctrl was set to 2. However this affects all applications on a system. With this method, applications can choose the proper speed/granularity trade-off for themselves. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: nikolag@ca.ibm.com Cc: Darren Hart <dvhltc@us.ibm.com> Cc: arjan@infradead.org Cc: jonathan@jonmasters.org LKML-Reference: <1250734414.6897.5.camel@localhost.localdomain> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-06-18gcov: enable GCOV_PROFILE_ALL for x86_64Peter Oberparleiter
Enable gcov profiling of the entire kernel on x86_64. Required changes include disabling profiling for: * arch/kernel/acpi/realmode and arch/kernel/boot/compressed: not linked to main kernel * arch/vdso, arch/kernel/vsyscall_64 and arch/kernel/hpet: profiling causes segfaults during boot (incompatible context) Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Merge branch 'linus' into perfcounters/coreIngo Molnar
Conflicts: arch/x86/kernel/irqinit.c arch/x86/kernel/irqinit_64.c arch/x86/kernel/traps.c arch/x86/mm/fault.c include/linux/sched.h kernel/exit.c
2009-06-10Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, nmi: Use predefined numbers instead of hardcoded one x86: asm/processor.h: remove double declaration x86, mtrr: replace MTRRdefType_MSR with msr-index's MSR_MTRRdefType x86, mtrr: replace MTRRfix4K_C0000_MSR with msr-index's MSR_MTRRfix4K_C0000 x86, mtrr: remove mtrr MSRs double declaration x86, mtrr: replace MTRRfix16K_80000_MSR with msr-index's MSR_MTRRfix16K_80000 x86, mtrr: replace MTRRfix64K_00000_MSR with msr-index's MSR_MTRRfix64K_00000 x86, mtrr: replace MTRRcap_MSR with msr-index's MSR_MTRRcap x86: mce: remove duplicated #include x86: msr-index.h remove duplicate MSR C001_0015 declaration x86: clean up arch/x86/kernel/tsc_sync.c a bit x86: use symbolic name for VM86_SIGNAL when used as vm86 default return x86: added 'ifndef _ASM_X86_IOMAP_H' to iomap.h x86: avoid multiple declaration of kstack_depth_to_print x86: vdso/vma.c declare vdso_enabled and arch_setup_additional_pages before they get used x86: clean up declarations and variables x86: apic/x2apic_cluster.c x86_cpu_to_logical_apicid should be static x86 early quirks: eliminate unused function
2009-06-05x86: Set context.vdso before installing the mappingPeter Zijlstra
In order to make arch_vma_name() work from inside install_special_mapping() we need to set the context.vdso before calling it. ( This is needed for performance counters to be able to track this special executable area. ) Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-30x86: gettimeofday() vDSO: fix segfault when tv == NULLJohn Wright
According to the gettimeofday(2) manual: If either tv or tz is NULL, the corresponding structure is not set or returned. Since it is legal to give NULL as the tv argument, the code should make sure tv is not NULL before trying to dereference it. This issue manifests itself on x86_64 when vdso=0 is not on the kernel command-line and libc uses the vDSO for gettimeofday() (e.g. glibc >= 2.7). A simple reproducer: #include <stdio.h> #include <sys/time.h> int main(void) { struct timezone tz; gettimeofday(NULL, &tz); return 0; } See http://bugs.debian.org/466491 for more details. [ Impact: fix gettimeofday(NULL, &tz) segfault ] Signed-off-by: John Wright <john.wright@hp.com> Cc: Andi Kleen <ak@suse.de> Cc: John Wright <john.wright@hp.com> LKML-Reference: <1241037121-14805-1-git-send-email-john.wright@hp.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-12x86: vdso/vma.c declare vdso_enabled and arch_setup_additional_pages before ↵Jaswinder Singh Rajput
they get used Impact: cleanup, address sparse warnings Addresses the problem pointed out by these sparse warning: arch/x86/vdso/vma.c:19:28: warning: symbol 'vdso_enabled' was not declared. Should it be static? arch/x86/vdso/vma.c:101:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static? Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> LKML-Reference: <1239548845.4170.2.camel@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-21x86, mm: rename TASK_SIZE64 => TASK_SIZE_MAXIngo Molnar
Impact: cleanup Rename TASK_SIZE64 to TASK_SIZE_MAX, and provide the define on 32-bit too. (mapped to TASK_SIZE) This allows 32-bit code to make use of the (former-) TASK_SIZE64 symbol as well, in a clean way. Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10x86: no stack protector for vdsoTejun Heo
Impact: avoid crash on vsyscall Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-28Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6Linus Torvalds
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6: (85 commits) [S390] provide documentation for hvc_iucv kernel parameter. [S390] convert ctcm printks to dev_xxx and pr_xxx macros. [S390] convert zfcp printks to pr_xxx macros. [S390] convert vmlogrdr printks to pr_xxx macros. [S390] convert zfcp dumper printks to pr_xxx macros. [S390] convert cpu related printks to pr_xxx macros. [S390] convert qeth printks to dev_xxx and pr_xxx macros. [S390] convert sclp printks to pr_xxx macros. [S390] convert iucv printks to dev_xxx and pr_xxx macros. [S390] convert ap_bus printks to pr_xxx macros. [S390] convert dcssblk and extmem printks messages to pr_xxx macros. [S390] convert monwriter printks to pr_xxx macros. [S390] convert s390 debug feature printks to pr_xxx macros. [S390] convert monreader printks to pr_xxx macros. [S390] convert appldata printks to pr_xxx macros. [S390] convert setup printks to pr_xxx macros. [S390] convert hypfs printks to pr_xxx macros. [S390] convert time printks to pr_xxx macros. [S390] convert cpacf printks to pr_xxx macros. [S390] convert cio printks to pr_xxx macros. ...
2008-12-25[S390] arch_setup_additional_pages argumentsMartin Schwidefsky
arch_setup_additional_pages currently gets two arguments, the binary format descripton and an indication if the process uses an executable stack or not. The second argument is not used by anybody, it could be removed without replacement. What actually does make sense is to pass an indication if the process uses the elf interpreter or not. The glibc code will not use anything from the vdso if the process does not use the dynamic linker, so for statically linked binaries the architecture backend can choose not to map the vdso. Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-11-12trace: rename unlikely profiler to branch profilerSteven Rostedt
Impact: name change of unlikely tracer and profiler Ingo Molnar suggested changing the config from UNLIKELY_PROFILE to BRANCH_PROFILING. I never did like the "unlikely" name so I went one step farther, and renamed all the unlikely configurations to a "BRANCH" variant. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12tracing: branch tracer, fix vdso crashIngo Molnar
Impact: fix bootup crash the branch tracer missed arch/x86/vdso/vclock_gettime.c from disabling tracing, which caused such bootup crashes: [ 201.840097] init[1]: segfault at 7fffed3fe7c0 ip 00007fffed3fea2e sp 000077 also clean up the ugly ifdefs in arch/x86/kernel/vsyscall_64.c by creating DISABLE_UNLIKELY_PROFILE facility for code to turn off instrumentation on a per file basis. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-21Merge branches 'x86/urgent', 'x86/amd-iommu', 'x86/apic', 'x86/cleanups', ↵Ingo Molnar
'x86/core', 'x86/cpu', 'x86/fixmap', 'x86/gart', 'x86/kprobes', 'x86/memtest', 'x86/modules', 'x86/nmi', 'x86/pat', 'x86/reboot', 'x86/setup', 'x86/step', 'x86/unify-pci', 'x86/uv', 'x86/xen' and 'xen-64bit' into x86/for-linus
2008-07-18x86: fix two modpost warningsJan Beulich
Even though it's only the difference of the two __initdata symbols that's being calculated, modpost still doesn't like this. So rather calculate the size once in an __init function and store it for later use. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-07-16x86_64: further cleanup of 32-bit compat syscall mechanismsJeremy Fitzhardinge
AMD only supports "syscall" from 32-bit compat usermode. Intel and Centaur(?) only support "sysenter" from 32-bit compat usermode. Set the X86 feature bits accordingly, and set up the vdso in accordance with those bits. On the offchance we run on in a 64-bit environment which supports neither syscall nor sysenter from 32-bit mode, then fall back to the int $0x80 vdso. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-07-14Merge branch 'auto-ftrace-next' into tracing/for-linusIngo Molnar
Conflicts: arch/x86/kernel/entry_32.S arch/x86/kernel/process_32.c arch/x86/kernel/process_64.c arch/x86/lib/Makefile include/asm-x86/irqflags.h kernel/Makefile kernel/sched.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-11x86_64: vdso32 cleanup using feature flagsJeremy Fitzhardinge
Use the X86_FEATURE_SYSENTER32 to remove hard-coded CPU vendor check. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08Merge branches 'x86/numa-fixes', 'x86/apic', 'x86/apm', 'x86/bitops', ↵Ingo Molnar
'x86/build', 'x86/cleanups', 'x86/cpa', 'x86/cpu', 'x86/defconfig', 'x86/gart', 'x86/i8259', 'x86/intel', 'x86/irqstats', 'x86/kconfig', 'x86/ldt', 'x86/mce', 'x86/memtest', 'x86/pat', 'x86/ptemask', 'x86/resumetrace', 'x86/threadinfo', 'x86/timers', 'x86/vdso' and 'x86/xen' into x86/devel
2008-06-16Merge branch 'linus' into tracing/ftraceIngo Molnar