[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH V10 09/20] COLO: Flush memory data from ram cache
From: |
Zhang Chen |
Subject: |
[Qemu-devel] [PATCH V10 09/20] COLO: Flush memory data from ram cache |
Date: |
Mon, 23 Jul 2018 03:33:39 +0800 |
During the time of VM's running, PVM may dirty some pages, we will transfer
PVM's dirty pages to SVM and store them into SVM's RAM cache at next checkpoint
time. So, the content of SVM's RAM cache will always be same with PVM's memory
after checkpoint.
Instead of flushing all content of PVM's RAM cache into SVM's MEMORY,
we do this in a more efficient way:
Only flush any page that dirtied by PVM since last checkpoint.
In this way, we can ensure SVM's memory same with PVM's.
Besides, we must ensure flush RAM cache before load device state.
Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Li Zhijian <address@hidden>
Reviewed-by: Dr. David Alan Gilbert <address@hidden>
---
migration/ram.c | 37 +++++++++++++++++++++++++++++++++++++
migration/trace-events | 2 ++
2 files changed, 39 insertions(+)
diff --git a/migration/ram.c b/migration/ram.c
index d1060f1337..4df85d69c1 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3830,6 +3830,39 @@ static bool postcopy_is_running(void)
return ps >= POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_END;
}
+/*
+ * Flush content of RAM cache into SVM's memory.
+ * Only flush the pages that be dirtied by PVM or SVM or both.
+ */
+static void colo_flush_ram_cache(void)
+{
+ RAMBlock *block = NULL;
+ void *dst_host;
+ void *src_host;
+ unsigned long offset = 0;
+
+ trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages);
+ rcu_read_lock();
+ block = QLIST_FIRST_RCU(&ram_list.blocks);
+
+ while (block) {
+ offset = migration_bitmap_find_dirty(ram_state, block, offset);
+
+ if (offset << TARGET_PAGE_BITS >= block->used_length) {
+ offset = 0;
+ block = QLIST_NEXT_RCU(block, next);
+ } else {
+ migration_bitmap_clear_dirty(ram_state, block, offset);
+ dst_host = block->host + (offset << TARGET_PAGE_BITS);
+ src_host = block->colo_cache + (offset << TARGET_PAGE_BITS);
+ memcpy(dst_host, src_host, TARGET_PAGE_SIZE);
+ }
+ }
+
+ rcu_read_unlock();
+ trace_colo_flush_ram_cache_end();
+}
+
static int ram_load(QEMUFile *f, void *opaque, int version_id)
{
int flags = 0, ret = 0, invalid_flags = 0;
@@ -4006,6 +4039,10 @@ static int ram_load(QEMUFile *f, void *opaque, int
version_id)
ret |= wait_for_decompress_done();
rcu_read_unlock();
trace_ram_load_complete(ret, seq_iter);
+
+ if (!ret && migration_incoming_in_colo_state()) {
+ colo_flush_ram_cache();
+ }
return ret;
}
diff --git a/migration/trace-events b/migration/trace-events
index fa0ff3f3bf..bd2d0cd25a 100644
--- a/migration/trace-events
+++ b/migration/trace-events
@@ -102,6 +102,8 @@ ram_dirty_bitmap_sync_start(void) ""
ram_dirty_bitmap_sync_wait(void) ""
ram_dirty_bitmap_sync_complete(void) ""
ram_state_resume_prepare(uint64_t v) "%" PRId64
+colo_flush_ram_cache_begin(uint64_t dirty_pages) "dirty_pages %" PRIu64
+colo_flush_ram_cache_end(void) ""
# migration/migration.c
await_return_path_close_on_source_close(void) ""
--
2.17.1
- [Qemu-devel] [PATCH V10 00/20] COLO: integrate colo frame with block replication and COLO proxy, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 01/20] filter-rewriter: Add TCP state machine and fix memory leak in connection_track_table, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 02/20] colo-compare: implement the process of checkpoint, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 03/20] colo-compare: use notifier to notify packets comparing result, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 04/20] COLO: integrate colo compare with colo frame, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 05/20] COLO: Add block replication into colo process, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 06/20] COLO: Remove colo_state migration struct, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 07/20] COLO: Load dirty pages into SVM's RAM cache firstly, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 08/20] ram/COLO: Record the dirty pages that SVM received, Zhang Chen, 2018/07/22
- [Qemu-devel] [PATCH V10 09/20] COLO: Flush memory data from ram cache,
Zhang Chen <=
- [Qemu-devel] [PATCH V10 10/20] qmp event: Add COLO_EXIT event to notify users while exited COLO, Zhang Chen, 2018/07/22
[Qemu-devel] [PATCH V10 11/20] qapi/migration.json: Rename COLO unknown mode to none mode., Zhang Chen, 2018/07/22
[Qemu-devel] [PATCH V10 12/20] qapi: Add new command to query colo status, Zhang Chen, 2018/07/22
[Qemu-devel] [PATCH V10 13/20] savevm: split the process of different stages for loadvm/savevm, Zhang Chen, 2018/07/22
[Qemu-devel] [PATCH V10 14/20] COLO: flush host dirty ram from cache, Zhang Chen, 2018/07/22
[Qemu-devel] [PATCH V10 15/20] net/net.c: Add net client type check function for COLO, Zhang Chen, 2018/07/22