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* x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov2016-01-30
| | | | | | | | | | | | | | | | | | | | | | Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> 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/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/um: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | On x86/um CONFIG_SMP is never defined. As a result, several macros match the asm-generic variant exactly. Drop the local definitions and pull in asm-generic/barrier.h instead. This is in preparation to refactoring this code area. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Richard Weinberger <richard@nod.at> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
* x86/asm/tsc: Remove rdtsc_barrier()Andy Lutomirski2015-07-06
| | | | | | | | | | | | | | | | | | | | | | | All callers have been converted to rdtsc_ordered(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang Rui <ray.huang@amd.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Weinberger <richard@nod.at> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm ML <kvm@vger.kernel.org> Link: http://lkml.kernel.org/r/9baa4ae9a1e7c7c282f9cb2f15bb6bf5c2004032.1434501121.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/arch: Rename set_mb() to smp_store_mb()Peter Zijlstra2015-05-19
| | | | | | | | | | | | | Since set_mb() is really about an smp_mb() -- not a IO/DMA barrier like mb() rename it to match the recent smp_load_acquire() and smp_store_release(). Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* locking/arch: Add WRITE_ONCE() to set_mb()Peter Zijlstra2015-05-19
| | | | | | | | | | | | Since we assume set_mb() to result in a single store followed by a full memory barrier, employ WRITE_ONCE(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge tag 'for-linus-4.1' of ↵Linus Torvalds2015-04-15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML updates from Richard Weinberger: - hostfs saw a face lifting - old/broken stuff was removed (SMP, HIGHMEM, SKAS3/4) - random cleanups and bug fixes * tag 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (26 commits) um: Print minimum physical memory requirement um: Move uml_postsetup in the init_thread stack um: add a kmsg_dumper x86, UML: fix integer overflow in ELF_ET_DYN_BASE um: hostfs: Reduce number of syscalls in readdir um: Remove broken highmem support um: Remove broken SMP support um: Remove SKAS3/4 support um: Remove ppc cruft um: Remove ia64 cruft um: Remove dead code from stacktrace hostfs: No need to box and later unbox the file mode hostfs: Use page_offset() hostfs: Set page flags in hostfs_readpage() correctly hostfs: Remove superfluous initializations in hostfs_open() hostfs: hostfs_open: Reset open flags upon each retry hostfs: Remove superfluous test in hostfs_open() hostfs: Report append flag in ->show_options() hostfs: Use __getname() in follow_link hostfs: Remove open coded strcpy() ...
| * um: Remove broken SMP supportRichard Weinberger2015-04-13
| | | | | | | | | | | | | | | | | | | | | | | | At times where UML used the TT mode to operate it had kind of SMP support. It never got finished nor was stable. Let's rip out that cruft and stop confusing developers which do tree-wide SMP cleanups. If someone wants SMP support UML it has do be done from scratch. Signed-off-by: Richard Weinberger <richard@nod.at>
* | x86/asm: Use alternative_2() in rdtsc_barrier()Borislav Petkov2015-02-23
|/ | | | | | | | ... now that we have it. Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Borislav Petkov <bp@suse.de>
* arch: Add lightweight memory barriers dma_rmb() and dma_wmb()Alexander Duyck2014-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are a number of situations where the mandatory barriers rmb() and wmb() are used to order memory/memory operations in the device drivers and those barriers are much heavier than they actually need to be. For example in the case of PowerPC wmb() calls the heavy-weight sync instruction when for coherent memory operations all that is really needed is an lsync or eieio instruction. This commit adds a coherent only version of the mandatory memory barriers rmb() and wmb(). In most cases this should result in the barrier being the same as the SMP barriers for the SMP case, however in some cases we use a barrier that is somewhere in between rmb() and smp_rmb(). For example on ARM the rmb barriers break down as follows: Barrier Call Explanation --------- -------- ---------------------------------- rmb() dsb() Data synchronization barrier - system dma_rmb() dmb(osh) data memory barrier - outer sharable smp_rmb() dmb(ish) data memory barrier - inner sharable These new barriers are not as safe as the standard rmb() and wmb(). Specifically they do not guarantee ordering between coherent and incoherent memories. The primary use case for these would be to enforce ordering of reads and writes when accessing coherent memory that is shared between the CPU and a device. It may also be noted that there is no dma_mb(). Most architectures don't provide a good mechanism for performing a coherent only full barrier without resorting to the same mechanism used in mb(). As such there isn't much to be gained in trying to define such a function. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: David Miller <davem@davemloft.net> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* arch: Cleanup read_barrier_depends() and commentsAlexander Duyck2014-12-11
| | | | | | | | | | | | | | | | | | This patch is meant to cleanup the handling of read_barrier_depends and smp_read_barrier_depends. In multiple spots in the kernel headers read_barrier_depends is defined as "do {} while (0)", however we then go into the SMP vs non-SMP sections and have the SMP version reference read_barrier_depends, and the non-SMP define it as yet another empty do/while. With this commit I went through and cleaned out the duplicate definitions and reduced the number of definitions down to 2 per header. In addition I moved the 50 line comments for the macro from the x86 and mips headers that defined it as an empty do/while to those that were actually defining the macro, alpha and blackfin. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* x86: Remove CONFIG_X86_OOSTOREDave Jones2014-03-11
| | | | | | | | | | | | | This was an optimization that made memcpy type benchmarks a little faster on ancient (Circa 1998) IDT Winchip CPUs. In real-life workloads, it wasn't even noticable, and I doubt anyone is running benchmarks on 16 year old silicon any more. Given this code has likely seen very little use over the last decade, let's just remove it. Signed-off-by: Dave Jones <davej@fedoraproject.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* um: Disintegrate asm/system.hRichard Weinberger2012-04-09
Signed-off-by: Richard Weinberger <richard@nod.at> Reported-by: Toralf Förster <toralf.foerster@gmx.de> CC: dhowells@redhat.com