From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54953) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dHo75-0004xc-BT for qemu-devel@nongnu.org; Mon, 05 Jun 2017 05:15:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dHo72-0006fC-3H for qemu-devel@nongnu.org; Mon, 05 Jun 2017 05:15:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57092) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dHo71-0006ev-R1 for qemu-devel@nongnu.org; Mon, 05 Jun 2017 05:15:48 -0400 Date: Mon, 5 Jun 2017 10:15:40 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170605091539.GD2109@work-vm> References: <1495539071-12995-1-git-send-email-a.perevalov@samsung.com> <1495539071-12995-3-git-send-email-a.perevalov@samsung.com> <20170531175458.GG3342@work-vm> <11a333fa-83ae-3982-9473-197d7876d33a@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <11a333fa-83ae-3982-9473-197d7876d33a@samsung.com> Subject: Re: [Qemu-devel] [PATCH V6 02/10] migration: pass MigrationIncomingState* into migration check functions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexey Perevalov Cc: qemu-devel@nongnu.org, i.maximets@samsung.com, peterx@redhat.com, eblake@redhat.com * Alexey Perevalov (a.perevalov@samsung.com) wrote: > On 05/31/2017 08:54 PM, Dr. David Alan Gilbert wrote: > > * Alexey Perevalov (a.perevalov@samsung.com) wrote: > > > That tiny refactoring is necessary to be able to set > > > UFFD_FEATURE_THREAD_ID while requesting features, and then > > > to create downtime context in case when kernel supports it. > > > > > > Signed-off-by: Alexey Perevalov > > > --- > > > migration/migration.c | 2 +- > > > migration/postcopy-ram.c | 10 +++++----- > > > migration/postcopy-ram.h | 2 +- > > > migration/savevm.c | 2 +- > > > 4 files changed, 8 insertions(+), 8 deletions(-) > > > > > > diff --git a/migration/migration.c b/migration/migration.c > > > index 0304c01..d735976 100644 > > > --- a/migration/migration.c > > > +++ b/migration/migration.c > > > @@ -789,7 +789,7 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params, > > > * special support. > > > */ > > > if (!old_postcopy_cap && runstate_check(RUN_STATE_INMIGRATE) && > > > - !postcopy_ram_supported_by_host()) { > > > + !postcopy_ram_supported_by_host(NULL)) { > > Why is that NULL rather than migration_incoming_get_current()? > > That's on the destination. > In current implementation, AFAIU, > migrate-set-capabilities with postcopy-ram argument should be done on source > machine only, > and it's not required on destination. And it is unnecessary requirement to > support userfaultfd on > source and check it there. Note the 'runstate_check(RUN_STATE_INMIGRATE)' - this check is made on the destination. While it's not strictly necessary for the management layer to do a migrate_set_capability postcopy-ram on the destination, it does it anyway to check the destination is capable of postcopy before it starts migration. Dave > > > > > Dave > > > > > /* postcopy_ram_supported_by_host will have emitted a more > > > * detailed message > > > */ > > > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > > > index a0489f6..4adab36 100644 > > > --- a/migration/postcopy-ram.c > > > +++ b/migration/postcopy-ram.c > > > @@ -59,7 +59,7 @@ struct PostcopyDiscardState { > > > #include > > > #include > > > -static bool ufd_version_check(int ufd) > > > +static bool ufd_version_check(int ufd, MigrationIncomingState *mis) > > > { > > > struct uffdio_api api_struct; > > > uint64_t ioctl_mask; > > > @@ -112,7 +112,7 @@ static int test_range_shared(const char *block_name, void *host_addr, > > > * normally fine since if the postcopy succeeds it gets turned back on at the > > > * end. > > > */ > > > -bool postcopy_ram_supported_by_host(void) > > > +bool postcopy_ram_supported_by_host(MigrationIncomingState *mis) > > > { > > > long pagesize = getpagesize(); > > > int ufd = -1; > > > @@ -135,7 +135,7 @@ bool postcopy_ram_supported_by_host(void) > > > } > > > /* Version and features check */ > > > - if (!ufd_version_check(ufd)) { > > > + if (!ufd_version_check(ufd, mis)) { > > > goto out; > > > } > > > @@ -512,7 +512,7 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis) > > > * Although the host check already tested the API, we need to > > > * do the check again as an ABI handshake on the new fd. > > > */ > > > - if (!ufd_version_check(mis->userfault_fd)) { > > > + if (!ufd_version_check(mis->userfault_fd, mis)) { > > > return -1; > > > } > > > @@ -650,7 +650,7 @@ void *postcopy_get_tmp_page(MigrationIncomingState *mis) > > > #else > > > /* No target OS support, stubs just fail */ > > > -bool postcopy_ram_supported_by_host(void) > > > +bool postcopy_ram_supported_by_host(MigrationIncomingState *mis) > > > { > > > error_report("%s: No OS support", __func__); > > > return false; > > > diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h > > > index 52d51e8..587a8b8 100644 > > > --- a/migration/postcopy-ram.h > > > +++ b/migration/postcopy-ram.h > > > @@ -14,7 +14,7 @@ > > > #define QEMU_POSTCOPY_RAM_H > > > /* Return true if the host supports everything we need to do postcopy-ram */ > > > -bool postcopy_ram_supported_by_host(void); > > > +bool postcopy_ram_supported_by_host(MigrationIncomingState *mis); > > > /* > > > * Make all of RAM sensitive to accesses to areas that haven't yet been written > > > diff --git a/migration/savevm.c b/migration/savevm.c > > > index f5e8194..61a6df7 100644 > > > --- a/migration/savevm.c > > > +++ b/migration/savevm.c > > > @@ -1356,7 +1356,7 @@ static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis) > > > return -1; > > > } > > > - if (!postcopy_ram_supported_by_host()) { > > > + if (!postcopy_ram_supported_by_host(mis)) { > > > postcopy_state_set(POSTCOPY_INCOMING_NONE); > > > return -1; > > > } > > > -- > > > 1.8.3.1 > > > > > -- > > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK > > > > > > > > -- > Best regards, > Alexey Perevalov -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK