similar to: [PATCH] xen/gnttab: leave lazy MMU mode in the case of a m2p override failure

This patch is a significant performance improvement for the m2p_override: about 6% using the gntdev device. Each m2p_add/remove_override call issues a MULTI_grant_table_op and a __flush_tlb_single if kmap_op != NULL. Batching all the calls together is a great performance benefit because it means issuing one hypercall total rather than two hypercall per page. If paravirt_lazy_mode is set

(This is a continuation of "[PATCH v9] xen/grant-table: Avoid m2p_override during mapping") The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping

(This is a continuation of "[PATCH v9] xen/grant-table: Avoid m2p_override during mapping") The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping

Hi Ian/Stefano, So, I''m back to using pfn space from maxphysaddr below. Stefano, you suggested ballooning, but that would be just too slow. There are lot of pages to be mapped, 4k at a time during guest creation, and I am afraid ballooning and hypercalls to populate EPT will be pretty slow. OTOH, there is tons of address space available between max-physaddr and max pfn in dom0. Stefano,

Hi all, this patch series enables xen-swiotlb on arm and arm64. It has been heavily reworked compared to the previous versions in order to achieve better performances and to address review comments. We are not using dma_mark_clean to ensure coherency anymore. We call the platform implementation of map_page and unmap_page. We assume that dom0 has been mapped 1:1 (physical address == machine

I''m trying to compile pvscsi out-of-tree, and I''m getting an error that set_phys_to_machine is not defined when I try to load the module (with the warning to that effect at compile time too). This used to work fine in pvops. It seems that netfront uses that symbol in a module so I''m confused as to why pvscsi can''t... any suggestions? Is it one of the virtues of

The epfn is being compared to (RDWR_COMPAT_MPT_VIRT_END - RDWR_COMPAT_MPT_VIRT_START) without a 2 bit shift, resulting in the epfn being compared to the size of the RDWR_COMPAT_MPT table in bytes instead of the maximum page frame number that the RDWR_COMPAT_MPT table can map. Signed-off-by: Malcolm Crossley <malcolm.crossley@citrix.com> diff -r 274e5accd62d -r 8b1e0a2ccd7f

build p2m mapping according to m2p mapping. Signed-off-by: Xin Li <xin.b.li@intel.com> Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel

This flag controls the meaning of gnttab_map_grant_ref.host_addr and specifies that the field contains a refernce to the pte entry to be used to perform the mapping. Therefore move the use of this flag to the point at which we actually use a reference to the pte instead of something else, splitting up the usage of the flag in this way is confusing and potentially error prone. The other flags are

This patch implements persistent grants for the xen-blk{front,back} mechanism. The effect of this change is to reduce the number of unmap operations performed, since they cause a (costly) TLB shootdown. This allows the I/O performance to scale better when a large number of VMs are performing I/O. Previously, the blkfront driver was supplied a bvec[] from the request queue. This was granted to

Is pte_offset_map allowed to happen within lazy mmu? I presume not, because you definitely don't want the mapping pte update to be deferred. Or, more specifically, is kunmap_atomic ever allowed within lazy mmu? I'm looking at kpte_clear_flush; I've already got a patch which turns this into a pv_op, along with a Xen implementation. But I think its probably an excess pv_op for a

Is pte_offset_map allowed to happen within lazy mmu? I presume not, because you definitely don't want the mapping pte update to be deferred. Or, more specifically, is kunmap_atomic ever allowed within lazy mmu? I'm looking at kpte_clear_flush; I've already got a patch which turns this into a pv_op, along with a Xen implementation. But I think its probably an excess pv_op for a

On 27/02/14 15:55, Zoltan Kiss wrote: > (This is a continuation of "[PATCH v9] xen/grant-table: Avoid m2p_override > during mapping") > > The grant mapping API does m2p_override unnecessarily: only gntdev needs it, > for blkback and future netback patches it just cause a lock contention, as > those pages never go to userspace. Therefore this series does the following:

Use list_for_each_entry_safe and remove the spin_lock acquisition in m2p_find_override: getting stale entries is OK because we should never get an m2p_find_override call looking for an entry that we are about to add or delete. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> --- arch/x86/xen/p2m.c | 9 ++------- 1 files changed, 2 insertions(+), 7 deletions(-) diff

Hello Roger Pau Monne, The patch 4d4f270f1880: "xen-blkback: move free persistent grants code" from Nov 16, 2012, leads to the following warning: drivers/block/xen-blkback/blkback.c:238 free_persistent_gnts() warn: 'persistent_gnt' was already freed. drivers/block/xen-blkback/blkback.c 232 pages[segs_to_unmap] = persistent_gnt->page; 233

Hello Roger Pau Monne, The patch 4d4f270f1880: "xen-blkback: move free persistent grants code" from Nov 16, 2012, leads to the following warning: drivers/block/xen-blkback/blkback.c:238 free_persistent_gnts() warn: 'persistent_gnt' was already freed. drivers/block/xen-blkback/blkback.c 232 pages[segs_to_unmap] = persistent_gnt->page; 233

[ REPOST: Apologies to anyone who has seen this before. It didn't make it onto any of the lists it should have. -J ] Hi Andrew, This series of patches lays the basic ground work for the paravirtualized kernel patches coming later on. I think this lot is ready for the rough-and-tumble world of the -mm tree. For the most part, these patches do nothing or very little. The patches should

[ REPOST: Apologies to anyone who has seen this before. It didn't make it onto any of the lists it should have. -J ] Hi Andrew, This series of patches lays the basic ground work for the paravirtualized kernel patches coming later on. I think this lot is ready for the rough-and-tumble world of the -mm tree. For the most part, these patches do nothing or very little. The patches should

At OLS I gave a talk on some of the Xen scalability inhibitors, and one of these was writable page tables. We went over why the feature does not scale, but just as important, we found that the uniprocessor case does not provide any advantage either. These tests were done on x86_64, so I wanted to run the 1-way test on 32 bit to show the same problem. So, I have run with writable PTs and

This is a cherry pick of two patches that add support for guest paged out frames in the XCP 2.6.32 dom0 patch queue. First patch propagates the ENOENT returned by the hypervisor in the case of a paged out page, all the way up the call chain to the MMAPBATCH_V2 ioctl. The ioctl is mainly used to harvest those return values and retry. The second patch adds retry loops to all backend grant