On Fri, Feb 16, 2018 at 01:16:15PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> Send a 'wake' request on a userfaultfd for a shared process.
> The address in the clients address space is specified together
> with the RAMBlock it was resolved to.
I think it's "providing a helper to send WAKE to uffd" rather than
really sending it.
Otherwise it looks good to me. Thanks,
>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> migration/postcopy-ram.c | 26 ++++++++++++++++++++++++++
> migration/postcopy-ram.h | 6 ++++++
> migration/trace-events | 1 +
> 3 files changed, 33 insertions(+)
>
> diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
> index 277ff749a0..67deae7e1c 100644
> --- a/migration/postcopy-ram.c
> +++ b/migration/postcopy-ram.c
> @@ -534,6 +534,25 @@ static int ram_block_enable_notify(const char
> *block_name, void *host_addr,
> return 0;
> }
>
> +int postcopy_wake_shared(struct PostCopyFD *pcfd,
> + uint64_t client_addr,
> + RAMBlock *rb)
> +{
> + size_t pagesize = qemu_ram_pagesize(rb);
> + struct uffdio_range range;
> + int ret;
> + trace_postcopy_wake_shared(client_addr, qemu_ram_get_idstr(rb));
> + range.start = client_addr & ~(pagesize - 1);
> + range.len = pagesize;
> + ret = ioctl(pcfd->fd, UFFDIO_WAKE, &range);
> + if (ret) {
> + error_report("%s: Failed to wake: %zx in %s (%s)",
> + __func__, (size_t)client_addr, qemu_ram_get_idstr(rb),
> + strerror(errno));
> + }
> + return ret;
> +}
> +
> /*
> * Callback from shared fault handlers to ask for a page,
> * the page must be specified by a RAMBlock and an offset in that rb
> @@ -951,6 +970,13 @@ void *postcopy_get_tmp_page(MigrationIncomingState *mis)
> return NULL;
> }
>
> +int postcopy_wake_shared(struct PostCopyFD *pcfd,
> + uint64_t client_addr,
> + RAMBlock *rb)
> +{
> + assert(0);
> + return -1;
> +}
> #endif
>
> /* -------------------------------------------------------------------------
> */
> diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h
> index 4c63f20df4..2e3dd844d5 100644
> --- a/migration/postcopy-ram.h
> +++ b/migration/postcopy-ram.h
> @@ -162,6 +162,12 @@ struct PostCopyFD {
> */
> void postcopy_register_shared_ufd(struct PostCopyFD *pcfd);
> void postcopy_unregister_shared_ufd(struct PostCopyFD *pcfd);
> +/* Notify a client ufd that a page is available
> + * Note: The 'client_address' is in the address space of the client
> + * program not QEMU
> + */
> +int postcopy_wake_shared(struct PostCopyFD *pcfd, uint64_t client_addr,
> + RAMBlock *rb);
> /* Callback from shared fault handlers to ask for a page */
> int postcopy_request_shared_page(struct PostCopyFD *pcfd, RAMBlock *rb,
> uint64_t client_addr, uint64_t offset);
> diff --git a/migration/trace-events b/migration/trace-events
> index 7c910b5479..b0acaaa8a0 100644
> --- a/migration/trace-events
> +++ b/migration/trace-events
> @@ -199,6 +199,7 @@ postcopy_ram_incoming_cleanup_entry(void) ""
> postcopy_ram_incoming_cleanup_exit(void) ""
> postcopy_ram_incoming_cleanup_join(void) ""
> postcopy_request_shared_page(const char *sharer, const char *rb, uint64_t
> rb_offset) "for %s in %s offset 0x%"PRIx64
> +postcopy_wake_shared(uint64_t client_addr, const char *rb) "at 0x%"PRIx64"
> in %s"
>
> save_xbzrle_page_skipping(void) ""
> save_xbzrle_page_overflow(void) ""
> --
> 2.14.3
>
--
Peter Xu
