Re: [PATCH]: Make migration handle errors a little better

Chris Lalancette
2008-01-24T19:41:58Z

[-- Attachment #1: Type: text/plain, Size: 683 bytes --]

Uri Lublin wrote:
> Patch looks good.
> Why did you define MIG_STAT_DIRTY_TRACK_FAIL and not
> MIG_STAT_KVM_SET_DIRTY_TRACKING_FAILED ?

Oops, I slightly misunderstood this bit in my last e-mail. You were saying that
there is already a "MIG_STAT_KVM_SET_DIRTY_TRACKING_FAILED" error flag. In the
new patch (attached), I've used this instead.

> Also we need to make sure, in case of a failure, that 'status' is
> updated and *s->has_error is freed. How about calling migrate_finish ?

And I now call migrate_finish() instead of migrate_close() in the error path, as
you suggest. Thanks again!

Signed-off-by: Chris Lalancette <clalance-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

[-- Attachment #2: kvm-60-migration-error-checking2.patch --]
[-- Type: text/x-patch, Size: 2055 bytes --]

diff --git a/qemu/migration.c b/qemu/migration.c
index 17ad77c..df0acf9 100644
--- a/qemu/migration.c
+++ b/qemu/migration.c
@@ -425,18 +425,26 @@ static int start_migration(MigrationState *s)
#endif

r = MIG_STAT_WRITE_FAILED;
- if (write_whole_buffer(s->fd, &running, sizeof(running)))
+ if (write_whole_buffer(s->fd, &running, sizeof(running))) {
+ perror("vm_running write failed");
goto out;
- if (write_whole_buffer(s->fd, &value, sizeof(value)))
+ }
+ if (write_whole_buffer(s->fd, &value, sizeof(value))) {
+ perror("phys_ram_size write failed");
goto out;
+ }

#ifdef USE_KVM
if (kvm_allowed) {
value = cpu_to_be32(n);
- if (write_whole_buffer(s->fd, &value, sizeof(value)))
+ if (write_whole_buffer(s->fd, &value, sizeof(value))) {
+ perror("phys_ram_size_bitmap size write failed");
goto out;
- if (write_whole_buffer(s->fd, phys_ram_page_exist_bitmap, n))
+ }
+ if (write_whole_buffer(s->fd, phys_ram_page_exist_bitmap, n)) {
+ perror("phys_ram_page_exist_bitmap write failed");
goto out;
+ }
}
#endif
fcntl(s->fd, F_SETFL, O_NONBLOCK);
@@ -456,7 +464,8 @@ static int start_migration(MigrationState *s)

if (cpu_physical_memory_set_dirty_tracking(1)) {
*s->has_error = MIG_STAT_KVM_SET_DIRTY_TRACKING_FAILED;
- return -1;
+ r = MIG_STAT_KVM_SET_DIRTY_TRACKING_FAILED;
+ goto out;
}

s->addr = 0;
@@ -470,6 +479,8 @@ static int start_migration(MigrationState *s)
qemu_mod_timer(s->timer, qemu_get_clock(rt_clock));
qemu_set_fd_handler2(s->fd, NULL, NULL, migrate_write, s);

+ r = 0;
+
out:
#ifdef USE_KVM
if (phys_ram_page_exist_bitmap)
@@ -498,8 +509,9 @@ static MigrationState *migration_init_fd(int detach, int fd)

current_migration = s;

- if (start_migration(s) == -1) {
+ if (start_migration(s)) {
term_printf("Could not start migration\n");
+ migrate_finish(s);
return NULL;
}

[-- Attachment #3: Type: text/plain, Size: 228 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org