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BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; ARC_NA(0.00)[]; ASN(0.00)[asn:25478, ipnet:::/0, country:RU]; MISSING_XM_UA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; MIME_TRACE(0.00)[0:+]; RCVD_TLS_ALL(0.00)[]; FUZZY_BLOCKED(0.00)[rspamd.com]; RCPT_COUNT_FIVE(0.00)[5]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: no action Received-SPF: pass client-ip=195.135.223.131; envelope-from=farosas@suse.de; helo=smtp-out2.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: 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 Prasad Pandit writes: > From: Prasad Pandit > > Refactor ram_save_target_page legacy and multifd > functions into one. Other than simplifying it, > it frees 'migration_ops' object from usage, so it > is expunged. > > When both Multifd and Postcopy modes are enabled, > to avoid errors, the Multifd threads are active until > migration reaches the Postcopy mode. This is done by > checking the state returned by migration_in_postcopy(). This patch should be just the actual refactoring on top of master, with no mention to postcopy at all. > > Signed-off-by: Prasad Pandit > --- > migration/multifd-nocomp.c | 3 +- > migration/ram.c | 74 ++++++++++++-------------------------- > 2 files changed, 24 insertions(+), 53 deletions(-) > > v1: Further refactor ram_save_target_page() function to conflate > save_zero_page() calls. > > Add migration_in_postcopy() call to check migration state > instead of combining it with migrate_multifd(). > > v0: https://lore.kernel.org/qemu-devel/20241029150908.1136894-1-ppandit@redhat.com/T/#u > > diff --git a/migration/multifd-nocomp.c b/migration/multifd-nocomp.c > index 55191152f9..e92821e8f6 100644 > --- a/migration/multifd-nocomp.c > +++ b/migration/multifd-nocomp.c > @@ -14,6 +14,7 @@ > #include "exec/ramblock.h" > #include "exec/target_page.h" > #include "file.h" > +#include "migration.h" > #include "multifd.h" > #include "options.h" > #include "qapi/error.h" > @@ -345,7 +346,7 @@ retry: > > int multifd_ram_flush_and_sync(void) > { > - if (!migrate_multifd()) { > + if (!migrate_multifd() || migration_in_postcopy()) { > return 0; > } > > diff --git a/migration/ram.c b/migration/ram.c > index 05ff9eb328..9d1ec6209c 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -467,13 +467,6 @@ void ram_transferred_add(uint64_t bytes) > } > } > > -struct MigrationOps { > - int (*ram_save_target_page)(RAMState *rs, PageSearchStatus *pss); > -}; > -typedef struct MigrationOps MigrationOps; > - > -MigrationOps *migration_ops; > - > static int ram_save_host_page_urgent(PageSearchStatus *pss); > > /* NOTE: page is the PFN not real ram_addr_t. */ > @@ -1323,9 +1316,9 @@ static int find_dirty_block(RAMState *rs, PageSearchStatus *pss) > pss->page = 0; > pss->block = QLIST_NEXT_RCU(pss->block, next); > if (!pss->block) { > - if (migrate_multifd() && > - (!migrate_multifd_flush_after_each_section() || > - migrate_mapped_ram())) { > + if (migrate_multifd() && !migration_in_postcopy() > + && (!migrate_multifd_flush_after_each_section() > + || migrate_mapped_ram())) { This is getting out of hand. We can't keep growing this condition every time something new comes up. Any ideas? > QEMUFile *f = rs->pss[RAM_CHANNEL_PRECOPY].pss_channel; > int ret = multifd_ram_flush_and_sync(); > if (ret < 0) { > @@ -1986,55 +1979,39 @@ int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len, > } > > /** > - * ram_save_target_page_legacy: save one target page > + * ram_save_target_page: save one target page to the precopy thread > + * OR to multifd workers. > * > - * Returns the number of pages written > + * Multifd mode: returns 1 if the page was queued, -1 otherwise. > + * Non-multifd mode: returns the number of pages written. Yes, although I wonder if we should keep documenting this when we only call this function for a single page and it always returns at most 1. > * > * @rs: current RAM state > * @pss: data about the page we want to send > */ > -static int ram_save_target_page_legacy(RAMState *rs, PageSearchStatus *pss) > +static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss) > { > ram_addr_t offset = ((ram_addr_t)pss->page) << TARGET_PAGE_BITS; > int res; > > + if (!migrate_multifd() > + || migrate_zero_page_detection() == ZERO_PAGE_DETECTION_LEGACY) { > + if (save_zero_page(rs, pss, offset)) { > + return 1; > + } > + } > + > + if (migrate_multifd() && !migration_in_postcopy()) { > + RAMBlock *block = pss->block; > + return ram_save_multifd_page(block, offset); > + } > + > if (control_save_page(pss, offset, &res)) { > return res; > } > > - if (save_zero_page(rs, pss, offset)) { > - return 1; > - } > - > return ram_save_page(rs, pss); > } > > -/** > - * ram_save_target_page_multifd: send one target page to multifd workers > - * > - * Returns 1 if the page was queued, -1 otherwise. > - * > - * @rs: current RAM state > - * @pss: data about the page we want to send > - */ > -static int ram_save_target_page_multifd(RAMState *rs, PageSearchStatus *pss) > -{ > - RAMBlock *block = pss->block; > - ram_addr_t offset = ((ram_addr_t)pss->page) << TARGET_PAGE_BITS; > - > - /* > - * While using multifd live migration, we still need to handle zero > - * page checking on the migration main thread. > - */ > - if (migrate_zero_page_detection() == ZERO_PAGE_DETECTION_LEGACY) { > - if (save_zero_page(rs, pss, offset)) { > - return 1; > - } > - } > - > - return ram_save_multifd_page(block, offset); > -} > - > /* Should be called before sending a host page */ > static void pss_host_page_prepare(PageSearchStatus *pss) > { > @@ -2121,7 +2098,7 @@ static int ram_save_host_page_urgent(PageSearchStatus *pss) > > if (page_dirty) { > /* Be strict to return code; it must be 1, or what else? */ ... this^ comment, for instance. > - if (migration_ops->ram_save_target_page(rs, pss) != 1) { > + if (ram_save_target_page(rs, pss) != 1) { > error_report_once("%s: ram_save_target_page failed", __func__); > ret = -1; > goto out; > @@ -2190,7 +2167,7 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss) > if (preempt_active) { > qemu_mutex_unlock(&rs->bitmap_mutex); > } > - tmppages = migration_ops->ram_save_target_page(rs, pss); > + tmppages = ram_save_target_page(rs, pss); > if (tmppages >= 0) { > pages += tmppages; > /* > @@ -2388,8 +2365,6 @@ static void ram_save_cleanup(void *opaque) > xbzrle_cleanup(); > multifd_ram_save_cleanup(); > ram_state_cleanup(rsp); > - g_free(migration_ops); > - migration_ops = NULL; > } > > static void ram_state_reset(RAMState *rs) > @@ -3055,13 +3030,8 @@ static int ram_save_setup(QEMUFile *f, void *opaque, Error **errp) > return ret; > } > > - migration_ops = g_malloc0(sizeof(MigrationOps)); > - > if (migrate_multifd()) { > multifd_ram_save_setup(); > - migration_ops->ram_save_target_page = ram_save_target_page_multifd; > - } else { > - migration_ops->ram_save_target_page = ram_save_target_page_legacy; > } > > bql_unlock();