All of lore.kernel.org
 help / color / mirror / Atom feed
From: Olaf Hering <olaf@aepfle.de>
To: xen-devel@lists.xenproject.org
Cc: Olaf Hering <olaf@aepfle.de>, Ian Jackson <iwj@xenproject.org>,
	Wei Liu <wl@xen.org>, Juergen Gross <jgross@suse.com>
Subject: [PATCH v20210616 26/36] tools: restore: write data directly into guest
Date: Wed, 16 Jun 2021 14:51:19 +0200	[thread overview]
Message-ID: <20210616125129.26563-27-olaf@aepfle.de> (raw)
In-Reply-To: <20210616125129.26563-1-olaf@aepfle.de>

Read incoming migration stream directly into the guest memory.
This avoids the memory allocation and copying, and the resulting
performance penalty.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
---
 tools/libs/saverestore/common.h  |   1 +
 tools/libs/saverestore/restore.c | 132 ++++++++++++++++++++++++++++++-
 2 files changed, 129 insertions(+), 4 deletions(-)

diff --git a/tools/libs/saverestore/common.h b/tools/libs/saverestore/common.h
index d479f1a918..5c440f28ec 100644
--- a/tools/libs/saverestore/common.h
+++ b/tools/libs/saverestore/common.h
@@ -243,6 +243,7 @@ struct sr_restore_arrays {
     xen_pfn_t mfns[MAX_BATCH_SIZE];
     int map_errs[MAX_BATCH_SIZE];
     void *guest_data[MAX_BATCH_SIZE];
+    struct iovec iov[MAX_BATCH_SIZE];
 
     /* populate_pfns */
     xen_pfn_t pp_mfns[MAX_BATCH_SIZE];
diff --git a/tools/libs/saverestore/restore.c b/tools/libs/saverestore/restore.c
index 877fd19a9b..d0148606bf 100644
--- a/tools/libs/saverestore/restore.c
+++ b/tools/libs/saverestore/restore.c
@@ -392,6 +392,122 @@ err:
     return rc;
 }
 
+/*
+ * Handle PAGE_DATA record from the stream.
+ * Given a list of pfns, their types, and a block of page data from the
+ * stream, populate and record their types, map the relevant subset and copy
+ * the data into the guest.
+ */
+static int handle_incoming_page_data(struct xc_sr_context *ctx,
+                                     struct xc_sr_rhdr *rhdr)
+{
+    xc_interface *xch = ctx->xch;
+    struct sr_restore_arrays *m = ctx->restore.m;
+    struct xc_sr_rec_page_data_header *pages = &m->pages;
+    uint64_t *pfn_nums = m->pages.pfn;
+    uint32_t i;
+    int rc, iov_idx;
+
+    rc = handle_static_data_end_v2(ctx);
+    if ( rc )
+        goto err;
+
+    /* First read and verify the header */
+    rc = read_exact(ctx->fd, pages, sizeof(*pages));
+    if ( rc )
+    {
+        PERROR("Could not read rec_pfn header");
+        goto err;
+    }
+
+    if ( verify_rec_page_hdr(ctx, rhdr->length, pages) == false )
+    {
+        rc = -1;
+        goto err;
+    }
+
+    /* Then read and verify the incoming pfn numbers */
+    rc = read_exact(ctx->fd, pfn_nums, sizeof(*pfn_nums) * pages->count);
+    if ( rc )
+    {
+        PERROR("Could not read rec_pfn data");
+        goto err;
+    }
+
+    if ( verify_rec_page_pfns(ctx, rhdr->length, pages) == false )
+    {
+        rc = -1;
+        goto err;
+    }
+
+    /* Finally read and verify the incoming pfn data */
+    rc = map_guest_pages(ctx, pages);
+    if ( rc )
+        goto err;
+
+    /* Prepare read buffers, either guest or throw away memory */
+    for ( i = 0, iov_idx = 0; i < pages->count; i++ )
+    {
+        if ( !m->guest_data[i] )
+            continue;
+
+        m->iov[iov_idx].iov_len = PAGE_SIZE;
+        if ( ctx->restore.verify )
+            m->iov[iov_idx].iov_base = ctx->restore.verify_buf + i * PAGE_SIZE;
+        else
+            m->iov[iov_idx].iov_base = m->guest_data[i];
+        iov_idx++;
+    }
+
+    if ( !iov_idx )
+        goto done;
+
+    rc = readv_exact(ctx->fd, m->iov, iov_idx);
+    if ( rc )
+    {
+        PERROR("read of %d pages failed", iov_idx);
+        goto err;
+    }
+
+    /* Post-processing of pfn data */
+    for ( i = 0, iov_idx = 0; i < pages->count; i++ )
+    {
+        if ( !m->guest_data[i] )
+            continue;
+
+        rc = ctx->restore.ops.localise_page(ctx, m->types[i], m->iov[iov_idx].iov_base);
+        if ( rc )
+        {
+            ERROR("Failed to localise pfn %#"PRIpfn" (type %#"PRIx32")",
+                  m->pfns[i], m->types[i] >> XEN_DOMCTL_PFINFO_LTAB_SHIFT);
+            goto err;
+
+        }
+
+        if ( ctx->restore.verify )
+        {
+            if ( memcmp(m->guest_data[i], m->iov[iov_idx].iov_base, PAGE_SIZE) )
+            {
+                ERROR("verify pfn %#"PRIpfn" failed (type %#"PRIx32")",
+                      m->pfns[i], m->types[i] >> XEN_DOMCTL_PFINFO_LTAB_SHIFT);
+            }
+        }
+
+        iov_idx++;
+    }
+
+done:
+    rc = 0;
+
+err:
+    if ( ctx->restore.guest_mapping )
+    {
+        xenforeignmemory_unmap(xch->fmem, ctx->restore.guest_mapping, ctx->restore.nr_mapped_pages);
+        ctx->restore.guest_mapping = NULL;
+    }
+    return rc;
+}
+
 /*
  * Handle PAGE_DATA record from an existing buffer
  * Given a list of pfns, their types, and a block of page data from the
@@ -773,11 +889,19 @@ static int process_incoming_record_header(struct xc_sr_context *ctx, struct xc_s
     struct xc_sr_record rec;
     int rc;
 
-    rc = read_record_data(ctx, ctx->fd, rhdr, &rec);
-    if ( rc )
-        return rc;
+    switch ( rhdr->type )
+    {
+    case REC_TYPE_PAGE_DATA:
+        rc = handle_incoming_page_data(ctx, rhdr);
+        break;
+    default:
+        rc = read_record_data(ctx, ctx->fd, rhdr, &rec);
+        if ( rc == 0 )
+            rc = process_buffered_record(ctx, &rec);;
+        break;
+    }
 
-    return process_buffered_record(ctx, &rec);
+    return rc;
 }
 
 


  parent reply	other threads:[~2021-06-16 13:07 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-16 12:50 [PATCH v20210616 00/36] leftover from 2020 Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 01/36] hotplug/Linux: fix starting of xenstored with restarting systemd Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 02/36] tools: add API to work with sevaral bits at once Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 03/36] xl: fix description of migrate --debug Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 04/36] tools: create libxensaverestore Olaf Hering
2021-06-16 15:17   ` Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 05/36] MAINTAINERS: add myself as saverestore maintainer Olaf Hering
2021-06-16 12:50 ` [PATCH v20210616 06/36] tools: add readv_exact to libxenctrl Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 07/36] tools: add sr_is_known_page_type to libsaverestore Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 08/36] tools: use sr_is_known_page_type Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 09/36] tools: unify type checking for data pfns in migration stream Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 10/36] tools: show migration transfer rate in send_dirty_pages Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 11/36] tools: prepare to allocate saverestore arrays once Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 12/36] tools: save: move mfns array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 13/36] tools: save: move types array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 14/36] tools: save: move errors array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 15/36] tools: save: move iov array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 16/36] tools: save: move rec_pfns array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 17/36] tools: save: move guest_data array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 18/36] tools: save: move local_pages array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 19/36] tools: restore: move types array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 20/36] tools: restore: move mfns array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 21/36] tools: restore: move map_errs array Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 22/36] tools: restore: move mfns array in populate_pfns Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 23/36] tools: restore: move pfns " Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 24/36] tools: restore: split record processing Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 25/36] tools: restore: split handle_page_data Olaf Hering
2021-06-16 12:51 ` Olaf Hering [this message]
2021-06-16 12:51 ` [PATCH v20210616 27/36] tools: recognize LIBXL_API_VERSION for 4.16 Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 28/36] tools: adjust libxl_domain_suspend to receive a struct props Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 29/36] tools: change struct precopy_stats to precopy_stats_t Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 30/36] tools: add callback to libxl for precopy_policy and precopy_stats_t Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 31/36] tools: add --max_iters to libxl_domain_suspend Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 32/36] tools: add --min_remaining " Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 33/36] tools: add --abort_if_busy " Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 34/36] tools: add API for expandable bitmaps Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 35/36] tools: use sr_bitmap for populated_pfns Olaf Hering
2021-06-16 12:51 ` [PATCH v20210616 36/36] tools: use superpages during restore of HVM guest Olaf Hering
2021-06-16 14:50 ` [PATCH v20210616 00/36] leftover from 2020 Andrew Cooper
2021-06-16 15:02   ` Olaf Hering
2021-06-17 11:02     ` Julien Grall
2021-06-17 17:40       ` Olaf Hering
2021-06-16 15:38   ` Olaf Hering
2021-06-17 11:24     ` Andrew Cooper
2021-06-17 14:55       ` Olaf Hering
2021-06-17 15:05         ` Andrew Cooper

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210616125129.26563-27-olaf@aepfle.de \
    --to=olaf@aepfle.de \
    --cc=iwj@xenproject.org \
    --cc=jgross@suse.com \
    --cc=wl@xen.org \
    --cc=xen-devel@lists.xenproject.org \
    --subject='Re: [PATCH v20210616 26/36] tools: restore: write data directly into guest' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.