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* s390: remove superfluous memblock_alloc() return value checksHeiko Carstens2016-01-19
| | | | | | | | | memblock_alloc() and memblock_alloc_base() will panic on their own if they can't find free memory. Therefore remove some pointless checks. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/numa: allocate memory with correct alignmentHeiko Carstens2016-01-19
| | | | | | | | | | | | | Allocating memory with a requested minimum alignment of 1 is wrong since pg_data_t contains a spinlock which requires an alignment of 4 bytes. Therefore fix this and ask for an alignment of 8 bytes like it is guarenteed for all kmalloc requests. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/irqflags: optimize irq restoreChristian Borntraeger2016-01-19
| | | | | | | | | | The ssm instruction takes longer that stnsm/stosm as it is often used to modify DAT and PER. We know that irqsave/irqrestore only deals with external and I/O interrupts and we know that irqrestore can transition only from disabled->disabled or disabled->enabled, so we can use the faster stosm. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* s390/mm: use TASK_MAX_SIZE where applicableDominik Dingel2016-01-19
| | | | | | | | | To improve readability we can use TASK_MAX_SIZE when we just check for the upper limit. All places explicitly dealing with 3 vs 4 level pgtables were left unchanged. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Reviewed-By: Sascha Silbe <silbe@linux.vnet.ibm.com>
* Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds2016-01-18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull virtio barrier rework+fixes from Michael Tsirkin: "This adds a new kind of barrier, and reworks virtio and xen to use it. Plus some fixes here and there" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (44 commits) checkpatch: add virt barriers checkpatch: check for __smp outside barrier.h checkpatch.pl: add missing memory barriers virtio: make find_vqs() checkpatch.pl-friendly virtio_balloon: fix race between migration and ballooning virtio_balloon: fix race by fill and leak s390: more efficient smp barriers s390: use generic memory barriers xen/events: use virt_xxx barriers xen/io: use virt_xxx barriers xenbus: use virt_xxx barriers virtio_ring: use virt_store_mb sh: move xchg_cmpxchg to a header by itself sh: support 1 and 2 byte xchg virtio_ring: update weak barriers to use virt_xxx Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb" asm-generic: implement virt_xxx memory barriers x86: define __smp_xxx xtensa: define __smp_xxx tile: define __smp_xxx ...
| * checkpatch: add virt barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | Add virt_ barriers to list of barriers to check for presence of a comment. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Julian Calaby <julian.calaby@gmail.com> Acked-by: Joe Perches <joe@perches.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * checkpatch: check for __smp outside barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduction of __smp barriers cleans up a bunch of duplicate code, but it gives people an additional handle onto a "new" set of barriers - just because they're prefixed with __* unfortunately doesn't stop anyone from using it (as happened with other arch stuff before.) Add a checkpatch test so it will trigger a warning. Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Julian Calaby <julian.calaby@gmail.com> Acked-by: Joe Perches <joe@perches.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * checkpatch.pl: add missing memory barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | SMP-only barriers were missing in checkpatch.pl Refactor code slightly to make adding more variants easier. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Julian Calaby <julian.calaby@gmail.com> Acked-by: Joe Perches <joe@perches.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * virtio: make find_vqs() checkpatch.pl-friendlyStefan Hajnoczi2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | checkpatch.pl wants arrays of strings declared as follows: static const char * const names[] = { "vq-1", "vq-2", "vq-3" }; Currently the find_vqs() function takes a const char *names[] argument so passing checkpatch.pl's const char * const names[] results in a compiler error due to losing the second const. This patch adjusts the find_vqs() prototype and updates all virtio transports. This makes it possible for virtio_balloon.c, virtio_input.c, virtgpu_kms.c, and virtio_rpmsg_bus.c to use the checkpatch.pl-friendly type. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
| * virtio_balloon: fix race between migration and ballooningMinchan Kim2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In balloon_page_dequeue, pages_lock should cover the loop (ie, list_for_each_entry_safe). Otherwise, the cursor page could be isolated by compaction and then list_del by isolation could poison the page->lru.{prev,next} so the loop finally could access wrong address like this. This patch fixes the bug. general protection fault: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 2 PID: 82 Comm: vballoon Not tainted 4.4.0-rc5-mm1-access_bit+ #1906 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff8800a7ff0000 ti: ffff8800a7fec000 task.ti: ffff8800a7fec000 RIP: 0010:[<ffffffff8115e754>] [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130 RSP: 0018:ffff8800a7fefdc0 EFLAGS: 00010246 RAX: ffff88013fff9a70 RBX: ffffea000056fe00 RCX: 0000000000002b7d RDX: ffff88013fff9a70 RSI: ffffea000056fe00 RDI: ffff88013fff9a68 RBP: ffff8800a7fefde8 R08: ffffea000056fda0 R09: 0000000000000000 R10: ffff8800a7fefd90 R11: 0000000000000001 R12: dead0000000000e0 R13: ffffea000056fe20 R14: ffff880138809070 R15: ffff880138809060 FS: 0000000000000000(0000) GS:ffff88013fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f229c10e000 CR3: 00000000b8b53000 CR4: 00000000000006a0 Stack: 0000000000000100 ffff880138809088 ffff880138809000 ffff880138809060 0000000000000046 ffff8800a7fefe28 ffffffff812c86d3 ffff880138809020 ffff880138809000 fffffffffff91900 0000000000000100 ffff880138809060 Call Trace: [<ffffffff812c86d3>] leak_balloon+0x93/0x1a0 [<ffffffff812c8bc7>] balloon+0x217/0x2a0 [<ffffffff8143739e>] ? __schedule+0x31e/0x8b0 [<ffffffff81078160>] ? abort_exclusive_wait+0xb0/0xb0 [<ffffffff812c89b0>] ? update_balloon_stats+0xf0/0xf0 [<ffffffff8105b6e9>] kthread+0xc9/0xe0 [<ffffffff8105b620>] ? kthread_park+0x60/0x60 [<ffffffff8143b4af>] ret_from_fork+0x3f/0x70 [<ffffffff8105b620>] ? kthread_park+0x60/0x60 Code: 8d 60 e0 0f 84 af 00 00 00 48 8b 43 20 a8 01 75 3b 48 89 d8 f0 0f ba 28 00 72 10 48 8b 03 f6 c4 08 75 2f 48 89 df e8 8c 83 f9 ff <49> 8b 44 24 20 4d 8d 6c 24 20 48 83 e8 20 4d 39 f5 74 7a 4c 89 RIP [<ffffffff8115e754>] balloon_page_dequeue+0x54/0x130 RSP <ffff8800a7fefdc0> ---[ end trace 43cf28060d708d5f ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Cc: <stable@vger.kernel.org> Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.com>
| * virtio_balloon: fix race by fill and leakMinchan Kim2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During my compaction-related stuff, I encountered a bug with ballooning. With repeated inflating and deflating cycle, guest memory( ie, cat /proc/meminfo | grep MemTotal) is decreased and couldn't be recovered. The reason is balloon_lock doesn't cover release_pages_balloon so struct virtio_balloon fields could be overwritten by race of fill_balloon(e,g, vb->*pfns could be critical). This patch fixes it in my test. Cc: <stable@vger.kernel.org> Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
| * s390: more efficient smp barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | As per: lkml.kernel.org/r/20150921112252.3c2937e1@mschwide atomics imply a barrier on s390, so s390 should change smp_mb__before_atomic and smp_mb__after_atomic to barrier() instead of smp_mb() and hence should not use the generic versions. Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * s390: use generic memory barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | The s390 kernel is SMP to 99.99%, we just didn't bother with a non-smp variant for the memory-barriers. If the generic header is used we'd get the non-smp version for free. It will save a small amount of text space for CONFIG_SMP=n. Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * xen/events: use virt_xxx barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | drivers/xen/events/events_fifo.c uses rmb() to communicate with the other side. For guests compiled with CONFIG_SMP, smp_rmb would be sufficient, so rmb() here is only needed if a non-SMP guest runs on an SMP host. Switch to the virt_rmb barrier which serves this exact purpose. Pull in asm/barrier.h here to make sure the file is self-contained. Suggested-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * xen/io: use virt_xxx barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | include/xen/interface/io/ring.h uses full memory barriers to communicate with the other side. For guests compiled with CONFIG_SMP, smp_wmb and smp_mb would be sufficient, so mb() and wmb() here are only needed if a non-SMP guest runs on an SMP host. Switch to virt_xxx barriers which serve this exact purpose. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * xenbus: use virt_xxx barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | drivers/xen/xenbus/xenbus_comms.c uses full memory barriers to communicate with the other side. For guests compiled with CONFIG_SMP, smp_wmb and smp_mb would be sufficient, so mb() and wmb() here are only needed if a non-SMP guest runs on an SMP host. Switch to virt_xxx barriers which serve this exact purpose. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * virtio_ring: use virt_store_mbMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | We need a full barrier after writing out event index, using virt_store_mb there seems better than open-coding. As usual, we need a wrapper to account for strong barriers. It's tempting to use this in vhost as well, for that, we'll need a variant of smp_store_mb that works on __user pointers. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * sh: move xchg_cmpxchg to a header by itselfMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | Looks like future sh variants will support a 4-byte cas which will be used to implement 1 and 2 byte xchg. This is exactly what we do for llsc now, move the portable part of the code into a separate header so it's easy to reuse. Suggested-by: Rich Felker <dalias@libc.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * sh: support 1 and 2 byte xchgMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | This completes the xchg implementation for sh architecture. Note: The llsc variant is tricky since this only supports 4 byte atomics, the existing implementation of 1 byte xchg is wrong: we need to do a 4 byte cmpxchg and retry if any bytes changed meanwhile. Write this in C for clarity. Suggested-by: Rich Felker <dalias@libc.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * virtio_ring: update weak barriers to use virt_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | virtio ring uses smp_wmb on SMP and wmb on !SMP, the reason for the later being that it might be talking to another kernel on the same SMP machine. This is exactly what virt_xxx barriers do, so switch to these instead of homegrown ifdef hacks. Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb"Michael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 9e1a27ea42691429e31f158cce6fc61bc79bb2e9. While that commit optimizes !CONFIG_SMP, it mixes up DMA and SMP concepts, making the code hard to figure out. A better way to optimize this is with the new __smp_XXX barriers. As a first step, go back to full rmb/wmb barriers for !SMP. We switch to __smp_XXX barriers in the next patch. Cc: Peter Zijlstra <peterz@infradead.org> Cc: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * asm-generic: implement virt_xxx memory barriersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Guests running within virtual machines might be affected by SMP effects even if the guest itself is compiled without SMP support. This is an artifact of interfacing with an SMP host while running an UP kernel. Using mandatory barriers for this use-case would be possible but is often suboptimal. In particular, virtio uses a bunch of confusing ifdefs to work around this, while xen just uses the mandatory barriers. To better handle this case, low-level virt_mb() etc macros are made available. These are implemented trivially using the low-level __smp_xxx macros, the purpose of these wrappers is to annotate those specific cases. These have the same effect as smp_mb() etc when SMP is enabled, but generate identical code for SMP and non-SMP systems. For example, virtual machine guests should use virt_mb() rather than smp_mb() when synchronizing against a (possibly SMP) host. Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * x86: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for x86, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
| * xtensa: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for xtensa, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * tile: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for tile, for use by virtualization. Some smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Note: for 32 bit, keep smp_mb__after_atomic around since it's faster than the generic implementation. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * sparc: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for sparc, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * sh: define __smp_xxx, fix smp_store_mb for !SMPMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | sh variant of smp_store_mb() calls xchg() on !SMP which is stronger than implied by both the name and the documentation. define __smp_store_mb instead: code in asm-generic/barrier.h will then define smp_store_mb correctly depending on CONFIG_SMP. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * s390: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for s390, for use by virtualization. Some smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Note: smp_mb, smp_rmb and smp_wmb are defined as full barriers unconditionally on this architecture. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * mips: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for mips, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Note: the only exception is smp_mb__before_llsc which is mips-specific. We define both the __smp_mb__before_llsc variant (for use in asm/barriers.h) and smp_mb__before_llsc (for use elsewhere on this architecture). Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * metag: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for metag, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Note: as __smp_XX macros should not depend on CONFIG_SMP, they can not use the existing fence() macro since that is defined differently between SMP and !SMP. For this reason, this patch introduces a wrapper metag_fence() that doesn't depend on CONFIG_SMP. fence() is then defined using that, depending on CONFIG_SMP. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: James Hogan <james.hogan@imgtec.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * ia64: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for ia64, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h This reduces the amount of arch-specific boiler-plate code. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Tony Luck <tony.luck@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * blackfin: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for blackfin, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * arm: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for arm, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h This reduces the amount of arch-specific boiler-plate code. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * arm64: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for arm64, for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h Note: arm64 does not support !SMP config, so smp_xxx and __smp_xxx are always equivalent. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * powerpc: define __smp_xxxMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This defines __smp_xxx barriers for powerpc for use by virtualization. smp_xxx barriers are removed as they are defined correctly by asm-generic/barriers.h This reduces the amount of arch-specific boiler-plate code. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Boqun Feng <boqun.feng@gmail.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * asm-generic: add __smp_xxx wrappersMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On !SMP, most architectures define their barriers as compiler barriers. On SMP, most need an actual barrier. Make it possible to remove the code duplication for !SMP by defining low-level __smp_xxx barriers which do not depend on the value of SMP, then use them from asm-generic conditionally. Besides reducing code duplication, these low level APIs will also be useful for virtualization, where a barrier is sometimes needed even if !SMP since we might be talking to another kernel on the same SMP system. Both virtio and Xen drivers will benefit. The smp_xxx variants should use __smp_XXX ones or barrier() depending on SMP, identically for all architectures. We keep ifndef guards around them for now - once/if all architectures are converted to use the generic code, we'll be able to remove these. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * x86: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | As on most architectures, on x86 read_barrier_depends and smp_read_barrier_depends are empty. Drop the local definitions and pull the generic ones from asm-generic/barrier.h instead: they are identical. 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: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
| * 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>
| * mips: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | On mips dma_rmb, dma_wmb, smp_store_mb, read_barrier_depends, smp_read_barrier_depends, smp_store_release and smp_load_acquire match the asm-generic variants 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: Peter Zijlstra (Intel) <peterz@infradead.org>
| * metag: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On metag dma_rmb, dma_wmb, smp_store_mb, read_barrier_depends, smp_read_barrier_depends, smp_store_release and smp_load_acquire match the asm-generic variants 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: James Hogan <james.hogan@imgtec.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * arm64: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | On arm64 nop, read_barrier_depends, smp_read_barrier_depends smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the asm-generic variants 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: Peter Zijlstra (Intel) <peterz@infradead.org>
| * arm: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On arm smp_store_mb, read_barrier_depends, smp_read_barrier_depends, smp_store_release, smp_load_acquire, smp_mb__before_atomic and smp_mb__after_atomic match the asm-generic variants 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: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * sparc: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On sparc 64 bit dma_rmb, dma_wmb, smp_store_mb, smp_mb, smp_rmb, smp_wmb, read_barrier_depends and smp_read_barrier_depends match the asm-generic variants exactly. Drop the local definitions and pull in asm-generic/barrier.h instead. nop uses __asm__ __volatile but is otherwise identical to the generic version, drop that as well. This is in preparation to refactoring this code area. Note: nop() was in processor.h and not in barrier.h as on other architectures. Nothing seems to depend on it being there though. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * s390: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | On s390 read_barrier_depends, smp_read_barrier_depends smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the asm-generic variants 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: Peter Zijlstra (Intel) <peterz@infradead.org>
| * powerpc: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On powerpc read_barrier_depends, smp_read_barrier_depends smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the asm-generic variants 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: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * ia64: reuse asm-generic/barrier.hMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | On ia64 smp_rmb, smp_wmb, read_barrier_depends, smp_read_barrier_depends and smp_store_mb() match the asm-generic variants 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: Tony Luck <tony.luck@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * ia64: rename nop->iosapic_nopMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | asm-generic/barrier.h defines a nop() macro. To be able to use this header on ia64, we shouldn't call local functions/variables nop(). There's one instance where this breaks on ia64: rename the function to iosapic_nop to avoid the conflict. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Tony Luck <tony.luck@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * asm-generic: guard smp_store_release/load_acquireMichael S. Tsirkin2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow architectures to override smp_store_release and smp_load_acquire by guarding the defines in asm-generic/barrier.h with ifndef directives. This is in preparation to reusing asm-generic/barrier.h on architectures which have their own definition of these macros. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
| * lcoking/barriers, arch: Use smp barriers in smp_store_release()Davidlohr Bueso2016-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With commit b92b8b35a2e ("locking/arch: Rename set_mb() to smp_store_mb()") it was made clear that the context of this call (and thus set_mb) is strictly for CPU ordering, as opposed to IO. As such all archs should use the smp variant of mb(), respecting the semantics and saving a mandatory barrier on UP. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <linux-arch@vger.kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: dave@stgolabs.net Link: http://lkml.kernel.org/r/1445975631-17047-3-git-send-email-dave@stgolabs.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds2016-01-18
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull arch/tile updates from Chris Metcalf: "This is a grab bag of changes that includes some NOHZ and context-tracking related changes, some debugging improvements, JUMP_LABEL support, and some fixes for tilepro allmodconfig support. We also remove the now-unused node_has_online_mem() definitions both for tile's asm/topology.h as well as in linux/topology.h itself" * git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: numa: remove stale node_has_online_mem() define arch/tile: move user_exit() to early kernel entry sequence tile: fix bug in setting PT_FLAGS_DISABLE_IRQ on kernel entry tile: fix tilepro casts for readl, writel, etc tile: fix a -Wframe-larger-than warning tile: include the syscall number in the backtrace MAINTAINERS: add git URL for tile arch/tile: adopt prepare_exit_to_usermode() model from x86 tile/jump_label: add jump label support for TILE-Gx tile: define a macro ktext_writable_addr to get writable kernel text address
generated by cgit v1.2.2 (git 2.25.0) at 2025-08-18 17:52:26 -0400