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MISSING_XM_UA(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo, imap1.dmz-prg2.suse.org:rdns] X-Rspamd-Queue-Id: 1CDAC33781 X-Rspamd-Action: no action X-Rspamd-Server: rspamd2.dmz-prg2.suse.org Received-SPF: pass client-ip=195.135.223.130; envelope-from=farosas@suse.de; helo=smtp-out1.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Peter Xu writes: > On Fri, Jan 23, 2026 at 10:47:10AM -0300, Fabiano Rosas wrote: >> Peter Xu writes: >> >> > It's neither accurate nor necessary. Use a proper helper to detect if it's >> > an iterable savevm state entry instead. >> >> Could you explain what exactly is_ram was supposed to mean? > > IIUC when introduced it was trying to capture the ram only, and that's also > why I said it's inaccurate, because ram is not the only thing that can > provide a save_setup() nowadays.. > >> >> > >> > Signed-off-by: Peter Xu >> > --- >> > migration/savevm.c | 15 ++++++++------- >> > 1 file changed, 8 insertions(+), 7 deletions(-) >> > >> > diff --git a/migration/savevm.c b/migration/savevm.c >> > index 61e873d90c..f1cd8c913d 100644 >> > --- a/migration/savevm.c >> > +++ b/migration/savevm.c >> > @@ -249,7 +249,6 @@ typedef struct SaveStateEntry { >> > const VMStateDescription *vmsd; >> > void *opaque; >> > CompatEntry *compat; >> > - int is_ram; >> > } SaveStateEntry; >> > >> > typedef struct SaveState { >> > @@ -816,10 +815,6 @@ int register_savevm_live(const char *idstr, >> > se->ops = ops; >> > se->opaque = opaque; >> > se->vmsd = NULL; >> > - /* if this is a live_savem then set is_ram */ >> > - if (ops->save_setup != NULL) { >> > - se->is_ram = 1; >> > - } >> > >> > pstrcat(se->idstr, sizeof(se->idstr), idstr); >> > >> > @@ -1866,6 +1861,12 @@ void qemu_savevm_live_state(QEMUFile *f) >> > qemu_put_byte(f, QEMU_VM_EOF); >> > } >> > >> > +/* Is a save state entry iterable (e.g. RAM)? */ >> > +static bool qemu_savevm_se_iterable(SaveStateEntry *se) >> > +{ >> > + return se->ops && se->ops->save_setup; >> >> So it could be iterable and not have .save_live_iterate? >> >> Also, what's the deal with slirp? AIUI, it would be considered is_ram? > > I guess no. Either in term of when it's introduced, or in theory of how I > understand this piece of code should work.. Because savevm_slirp_state > doesn't provide save_setup(). > Oops, I misread save_state vs. save_setup. > Note that this patch didn't really change the fact on how it works, even if > I _think_ this is broken.. I want to leave it for later, making sure this > patch (while doing the cleanup) doesn't introduce functional changes. > That's always fine. > So I expect things to break if e.g. COLO is used with VFIO devices (that > supports migrations), where it also provides save_setup(), but actually > COLO will not properly sync VFIO states. Likely nobody is using it anyway. > > It's also the same to Xen's xen-save-devices-state QMP command. It looks > to me Xen is playing some "split savevm" work here, however I don't know > whether it'll always workout these days when there're special devices that > provide save_setup(). > Hm, ok. Let's leave it then. >> >> > +} >> > + >> > int qemu_save_device_state(QEMUFile *f) >> > { >> > Error *local_err = NULL; >> > @@ -1876,7 +1877,7 @@ int qemu_save_device_state(QEMUFile *f) >> > QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { >> > int ret; >> > >> > - if (se->is_ram) { >> > + if (qemu_savevm_se_iterable(se)) { >> >> Hmm, qemu_savevm_state_setup has: >> >> if (!se->ops || !se->ops->save_setup) { >> continue; >> } >> >> therefore: >> >> if (!qemu_savevm_se_iterable(se)) { >> continue; >> } >> >> Maybe it would be more practical to put these in a separate list already >> while registering. > > This is a question about performance, my gut feeling is looping over with > one queue would be fine for now, but even if not, it'll be further question > to ask after above (on correctness..). > > So I plan to be focused on the cleanup part for now in this series.. > Reviewed-by: Fabiano Rosas