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BAYES_HAM(-3.00)[100.00%]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_MISSING_CHARSET(0.50)[]; 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)[]; MIME_TRACE(0.00)[0:+]; TO_DN_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from,2a07:de40:b281:106:10:150:64:167:received]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; RCVD_TLS_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,suse.de:dkim,suse.de:email]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Action: no action X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: 1BFBF5BE1F 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_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_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 In vmstate_save|load_vmsd[_v], move the code handling VMS_ARRAY_OF_POINTER all to the same block. These functions deal with single elements, scalar arrays and arrays of pointers, of which the latter is the most complex code. Group that use-case so it's easier to reason about. This allows for a significant design cleanup, which is to stop using the inner_field variable in the case where there is NO pointer marker. Now the inner_field is internal to the VMS_ARRAY_OF_POINTER code. By adding a save_field boolean, we can reuse the "actual field" write for the !use_marker case. This brings the benefit of being able to drop the field->size specialization. Like so: === before: size = vmstate_size(); if (use_marker) { inner_field = fake; } else { inner_field = field; } vmstate_save_field_with_vmdesc(inner_field, size) if (use_marker && !curr) { vmstate_save_field_with_vmdesc(field, field->size) } after: size = vmstate_size(); if (use_marker) { inner_field = fake; vmstate_save_field_with_vmdesc(inner_field, 1) save_field = !curr; } if (save_field) { vmstate_save_field_with_vmdesc(field, size) } Signed-off-by: Fabiano Rosas --- migration/vmstate.c | 193 +++++++++++++++++++++----------------------- 1 file changed, 92 insertions(+), 101 deletions(-) diff --git a/migration/vmstate.c b/migration/vmstate.c index 7a12245d36..a190c3f63f 100644 --- a/migration/vmstate.c +++ b/migration/vmstate.c @@ -277,12 +277,6 @@ bool vmstate_load_vmsd(QEMUFile *f, const VMStateDescription *vmsd, void *first_elem = opaque + field->offset; int i, n_elems = vmstate_n_elems(opaque, field); int size = vmstate_size(opaque, field); - /* - * When this is enabled, it means we will always push a ptr - * marker first for each element saying if it's populated. - */ - bool use_dynamic_array = - field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC; vmstate_handle_alloc(first_elem, field, opaque); if (field->flags & VMS_POINTER) { @@ -294,36 +288,40 @@ bool vmstate_load_vmsd(QEMUFile *f, const VMStateDescription *vmsd, /* If we will process the load of field? */ bool load_field = true; bool ok = true; - bool use_marker_field; void *curr_elem_p = first_elem + size * i; void *curr_elem = curr_elem_p; if (field->flags & VMS_ARRAY_OF_POINTER) { + bool use_dynamic_array = + field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC; + bool use_marker_field; + curr_elem = *(void **)curr_elem_p; - } - use_marker_field = use_dynamic_array || (!curr_elem && size); + use_marker_field = use_dynamic_array || !curr_elem; - if (use_marker_field) { - /* Read the marker instead of VMSD first */ - if (!vmstate_ptr_marker_load(f, &load_field, errp)) { - trace_vmstate_load_field_error(field->name, -EINVAL); - return false; - } + if (use_marker_field) { + /* Read the marker instead of VMSD first */ + if (!vmstate_ptr_marker_load(f, &load_field, errp)) { + trace_vmstate_load_field_error(field->name, + -EINVAL); + return false; + } - if (load_field) { - /* - * When reaching here, it means we received a - * non-NULL ptr marker, so we need to populate the - * field before loading it. - * - * NOTE: do not use vmstate_size() here, because we - * need the object size, not entry size of the - * array. - */ - curr_elem = g_malloc0(field->size); - /* Remember to update the root pointer! */ - *(void **)curr_elem_p = curr_elem; + if (load_field) { + /* + * When reaching here, it means we received a + * non-NULL ptr marker, so we need to populate the + * field before loading it. + * + * NOTE: do not use vmstate_size() here, because we + * need the object size, not entry size of the + * array. + */ + curr_elem = g_malloc0(field->size); + /* Remember to update the root pointer! */ + *(void **)curr_elem_p = curr_elem; + } } } @@ -625,13 +623,6 @@ static bool vmstate_save_vmsd_v(QEMUFile *f, const VMStateDescription *vmsd, bool is_null_prev = false; bool use_vmdesc = true; - /* - * When this is enabled, it means we will always push a ptr - * marker first for each element saying if it's populated. - */ - bool use_dynamic_array = - field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC; - trace_vmstate_save_state_loop(vmsd->name, field->name, n_elems); if (field->flags & VMS_POINTER) { first_elem = *(void **)first_elem; @@ -639,83 +630,83 @@ static bool vmstate_save_vmsd_v(QEMUFile *f, const VMStateDescription *vmsd, } for (i = 0; i < n_elems; i++) { + bool save_field = true; void *curr_elem = first_elem + size * i; - const VMStateField *inner_field; - bool use_marker_field, is_null = false; int max_elems = n_elems - i; if (field->flags & VMS_ARRAY_OF_POINTER) { + const VMStateField *inner_field; + bool use_marker_field, is_null, use_dynamic_array; + assert(curr_elem); curr_elem = *(void **)curr_elem; + is_null = !curr_elem; - } - use_marker_field = use_dynamic_array || is_null; - - if (use_marker_field) { - inner_field = vmsd_create_ptr_marker_field(field); - } else { - inner_field = field; - } - - /* - * This logic only matters when dumping VM Desc, and only - * when the VMSD field can be compressed. - * - * Due to the fake nullptr handling above, if there's mixed - * null/non-null data, it doesn't make sense to emit a - * compressed array representation spanning the entire array - * because the field types will be different (e.g. struct - * vs. nullptr). Search ahead for the next null/non-null element - * and start a new compressed array if found. - */ - if (vmdesc && vmsd_can_compress(field) && - (field->flags & VMS_ARRAY_OF_POINTER) && - is_null != is_null_prev) { - - is_null_prev = is_null; - use_vmdesc = true; - - for (int j = i + 1; j < n_elems; j++) { - void *elem = *(void **)(first_elem + size * j); - bool elem_is_null = !elem; - - if (is_null != elem_is_null) { - max_elems = j - i; - break; - } - } - } - - if (use_dynamic_array) { - use_vmdesc = true; - } - - ok = vmstate_save_field_with_vmdesc(f, curr_elem, size, vmsd, - inner_field, - use_vmdesc ? vmdesc : NULL, - i, max_elems, errp); - - /* If we used a fake temp field.. free it now */ - if (use_marker_field) { - g_clear_pointer((gpointer *)&inner_field, g_free); - } - - if (!ok) { - goto out; - } - - /* - * If we're using dynamic array and the element is - * populated, dump the real object right after the marker. - */ - if (use_dynamic_array && curr_elem) { /* - * NOTE: do not use vmstate_size() here because we want - * to dump the real VMSD object now. + * When this is enabled, it means we will always push a ptr + * marker first for each element saying if it's populated. */ + use_dynamic_array = + field->flags & VMS_ARRAY_OF_POINTER_AUTO_ALLOC; + + use_marker_field = use_dynamic_array || is_null; + + if (vmdesc && vmsd_can_compress(field)) { + /* + * This logic only matters when dumping VM + * Desc, and only when the VMSD field can be + * compressed. + * + * Due to the fake nullptr handling above, if + * there's mixed null/non-null data, it + * doesn't make sense to emit a compressed + * array representation spanning the entire + * array because the field types will be + * different (e.g. struct vs. nullptr). Search + * ahead for the next null/non-null element + * and start a new compressed array if found. + */ + if (is_null != is_null_prev) { + is_null_prev = is_null; + use_vmdesc = true; + + for (int j = i + 1; j < n_elems; j++) { + void *elem = *(void **)(first_elem + size * j); + bool elem_is_null = !elem; + + if (is_null != elem_is_null) { + max_elems = j - i; + break; + } + } + } + } + + if (use_dynamic_array) { + use_vmdesc = true; + } + + if (use_marker_field) { + inner_field = vmsd_create_ptr_marker_field(field); + + ok = vmstate_save_field_with_vmdesc( + f, curr_elem, 1, vmsd, inner_field, + use_vmdesc ? vmdesc : NULL, i, max_elems, errp); + + g_clear_pointer((gpointer *)&inner_field, g_free); + + if (!ok) { + goto out; + } + + save_field = !!curr_elem; + } + } + + if (save_field) { ok = vmstate_save_field_with_vmdesc( - f, curr_elem, field->size, vmsd, field, + f, curr_elem, size, vmsd, field, use_vmdesc ? vmdesc : NULL, i, max_elems, errp); if (!ok) { -- 2.51.0