Merge remote-tracking branch 'remotes/quintela-gitlab/tags/migration-20220128-pull-request' into staging

Migration Pull request (Take 2)

Hi

This time I have disabled vmstate canary patches form Dave Gilbert.

Let's see if it works.

Later, Juan.

# gpg: Signature made Fri 28 Jan 2022 18:30:25 GMT
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/quintela-gitlab/tags/migration-20220128-pull-request: (36 commits)
  migration: Move temp page setup and cleanup into separate functions
  migration: Simplify unqueue_page()
  migration: Add postcopy_has_request()
  migration: Enable UFFD_FEATURE_THREAD_ID even without blocktime feat
  migration: No off-by-one for pss->page update in host page size
  migration: Tally pre-copy, downtime and post-copy bytes independently
  migration: Introduce ram_transferred_add()
  migration: Don't return for postcopy_send_discard_bm_ram()
  migration: Drop return code for disgard ram process
  migration: Do chunk page in postcopy_each_ram_send_discard()
  migration: Drop postcopy_chunk_hostpages()
  migration: Don't return for postcopy_chunk_hostpages()
  migration: Drop dead code of ram_debug_dump_bitmap()
  migration/ram: clean up unused comment.
  migration: Report the error returned when save_live_iterate fails
  migration/migration.c: Remove the MIGRATION_STATUS_ACTIVE when migration finished
  migration/migration.c: Avoid COLO boot in postcopy migration
  migration/migration.c: Add missed default error handler for migration state
  Remove unnecessary minimum_version_id_old fields
  multifd: Rename pages_used to normal_pages
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 57 insertions, 39 deletions

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index d18b5d05b2..e662dd05cc 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -283,15 +283,13 @@ static bool ufd_check_and_apply(int ufd, MigrationIncomingState *mis)
     }
 
 #ifdef UFFD_FEATURE_THREAD_ID
-    if (migrate_postcopy_blocktime() && mis &&
-        UFFD_FEATURE_THREAD_ID & supported_features) {
-        /* kernel supports that feature */
-        /* don't create blocktime_context if it exists */
-        if (!mis->blocktime_ctx) {
-            mis->blocktime_ctx = blocktime_context_new();
-        }
-
+    if (UFFD_FEATURE_THREAD_ID & supported_features) {
         asked_features |= UFFD_FEATURE_THREAD_ID;
+        if (migrate_postcopy_blocktime()) {
+            if (!mis->blocktime_ctx) {
+                mis->blocktime_ctx = blocktime_context_new();
+            }
+        }
     }
 #endif
 
@@ -525,6 +523,19 @@ int postcopy_ram_incoming_init(MigrationIncomingState *mis)
     return 0;
 }
 
+static void postcopy_temp_pages_cleanup(MigrationIncomingState *mis)
+{
+    if (mis->postcopy_tmp_page) {
+        munmap(mis->postcopy_tmp_page, mis->largest_page_size);
+        mis->postcopy_tmp_page = NULL;
+    }
+
+    if (mis->postcopy_tmp_zero_page) {
+        munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size);
+        mis->postcopy_tmp_zero_page = NULL;
+    }
+}
+
 /*
  * At the end of a migration where postcopy_ram_incoming_init was called.
  */
@@ -566,14 +577,8 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis)
         }
     }
 
-    if (mis->postcopy_tmp_page) {
-        munmap(mis->postcopy_tmp_page, mis->largest_page_size);
-        mis->postcopy_tmp_page = NULL;
-    }
-    if (mis->postcopy_tmp_zero_page) {
-        munmap(mis->postcopy_tmp_zero_page, mis->largest_page_size);
-        mis->postcopy_tmp_zero_page = NULL;
-    }
+    postcopy_temp_pages_cleanup(mis);
+
     trace_postcopy_ram_incoming_cleanup_blocktime(
             get_postcopy_total_blocktime());
 
@@ -1084,6 +1089,40 @@ retry:
     return NULL;
 }
 
+static int postcopy_temp_pages_setup(MigrationIncomingState *mis)
+{
+    int err;
+
+    mis->postcopy_tmp_page = mmap(NULL, mis->largest_page_size,
+                                  PROT_READ | PROT_WRITE,
+                                  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (mis->postcopy_tmp_page == MAP_FAILED) {
+        err = errno;
+        mis->postcopy_tmp_page = NULL;
+        error_report("%s: Failed to map postcopy_tmp_page %s",
+                     __func__, strerror(err));
+        return -err;
+    }
+
+    /*
+     * Map large zero page when kernel can't use UFFDIO_ZEROPAGE for hugepages
+     */
+    mis->postcopy_tmp_zero_page = mmap(NULL, mis->largest_page_size,
+                                       PROT_READ | PROT_WRITE,
+                                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+    if (mis->postcopy_tmp_zero_page == MAP_FAILED) {
+        err = errno;
+        mis->postcopy_tmp_zero_page = NULL;
+        error_report("%s: Failed to map large zero page %s",
+                     __func__, strerror(err));
+        return -err;
+    }
+
+    memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size);
+
+    return 0;
+}
+
 int postcopy_ram_incoming_setup(MigrationIncomingState *mis)
 {
     /* Open the fd for the kernel to give us userfaults */
@@ -1124,32 +1163,11 @@ int postcopy_ram_incoming_setup(MigrationIncomingState *mis)
         return -1;
     }
 
-    mis->postcopy_tmp_page = mmap(NULL, mis->largest_page_size,
-                                  PROT_READ | PROT_WRITE, MAP_PRIVATE |
-                                  MAP_ANONYMOUS, -1, 0);
-    if (mis->postcopy_tmp_page == MAP_FAILED) {
-        mis->postcopy_tmp_page = NULL;
-        error_report("%s: Failed to map postcopy_tmp_page %s",
-                     __func__, strerror(errno));
+    if (postcopy_temp_pages_setup(mis)) {
+        /* Error dumped in the sub-function */
         return -1;
     }
 
-    /*
-     * Map large zero page when kernel can't use UFFDIO_ZEROPAGE for hugepages
-     */
-    mis->postcopy_tmp_zero_page = mmap(NULL, mis->largest_page_size,
-                                       PROT_READ | PROT_WRITE,
-                                       MAP_PRIVATE | MAP_ANONYMOUS,
-                                       -1, 0);
-    if (mis->postcopy_tmp_zero_page == MAP_FAILED) {
-        int e = errno;
-        mis->postcopy_tmp_zero_page = NULL;
-        error_report("%s: Failed to map large zero page %s",
-                     __func__, strerror(e));
-        return -e;
-    }
-    memset(mis->postcopy_tmp_zero_page, '\0', mis->largest_page_size);
-
     trace_postcopy_ram_enable_notify();
 
     return 0;