[RFC PATCH 1/7] migration/multifd: Reduce access to p->pages

Fabiano Rosas posted 7 patches 5 months, 1 week ago
Maintainers: Peter Xu <peterx@redhat.com>, Fabiano Rosas <farosas@suse.de>
[RFC PATCH 1/7] migration/multifd: Reduce access to p->pages
Posted by Fabiano Rosas 5 months, 1 week ago
I'm about to replace the p->pages pointer with an opaque pointer, so
do a cleanup now to reduce direct accesses to p->page, which makes the
next diffs cleaner.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 migration/multifd-qpl.c  |  8 +++++---
 migration/multifd-uadk.c |  9 +++++----
 migration/multifd-zlib.c |  2 +-
 migration/multifd-zstd.c |  2 +-
 migration/multifd.c      | 13 +++++++------
 5 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/migration/multifd-qpl.c b/migration/multifd-qpl.c
index 9265098ee7..f8c84c52cf 100644
--- a/migration/multifd-qpl.c
+++ b/migration/multifd-qpl.c
@@ -404,13 +404,14 @@ retry:
 static void multifd_qpl_compress_pages_slow_path(MultiFDSendParams *p)
 {
     QplData *qpl = p->compress_data;
+    MultiFDPages_t *pages = p->pages;
     uint32_t size = p->page_size;
     qpl_job *job = qpl->sw_job;
     uint8_t *zbuf = qpl->zbuf;
     uint8_t *buf;
 
-    for (int i = 0; i < p->pages->normal_num; i++) {
-        buf = p->pages->block->host + p->pages->offset[i];
+    for (int i = 0; i < pages->normal_num; i++) {
+        buf = pages->block->host + pages->offset[i];
         multifd_qpl_prepare_comp_job(job, buf, zbuf, size);
         if (qpl_execute_job(job) == QPL_STS_OK) {
             multifd_qpl_fill_packet(i, p, zbuf, job->total_out);
@@ -498,6 +499,7 @@ static void multifd_qpl_compress_pages(MultiFDSendParams *p)
 static int multifd_qpl_send_prepare(MultiFDSendParams *p, Error **errp)
 {
     QplData *qpl = p->compress_data;
+    MultiFDPages_t *pages = p->pages;
     uint32_t len = 0;
 
     if (!multifd_send_prepare_common(p)) {
@@ -505,7 +507,7 @@ static int multifd_qpl_send_prepare(MultiFDSendParams *p, Error **errp)
     }
 
     /* The first IOV is used to store the compressed page lengths */
-    len = p->pages->normal_num * sizeof(uint32_t);
+    len = pages->normal_num * sizeof(uint32_t);
     multifd_qpl_fill_iov(p, (uint8_t *) qpl->zlen, len);
     if (qpl->hw_avail) {
         multifd_qpl_compress_pages(p);
diff --git a/migration/multifd-uadk.c b/migration/multifd-uadk.c
index d12353fb21..b8ba3cd9c1 100644
--- a/migration/multifd-uadk.c
+++ b/migration/multifd-uadk.c
@@ -174,19 +174,20 @@ static int multifd_uadk_send_prepare(MultiFDSendParams *p, Error **errp)
     uint32_t hdr_size;
     uint8_t *buf = uadk_data->buf;
     int ret = 0;
+    MultiFDPages_t *pages = p->pages;
 
     if (!multifd_send_prepare_common(p)) {
         goto out;
     }
 
-    hdr_size = p->pages->normal_num * sizeof(uint32_t);
+    hdr_size = pages->normal_num * sizeof(uint32_t);
     /* prepare the header that stores the lengths of all compressed data */
     prepare_next_iov(p, uadk_data->buf_hdr, hdr_size);
 
-    for (int i = 0; i < p->pages->normal_num; i++) {
+    for (int i = 0; i < pages->normal_num; i++) {
         struct wd_comp_req creq = {
             .op_type = WD_DIR_COMPRESS,
-            .src     = p->pages->block->host + p->pages->offset[i],
+            .src     = pages->block->host + pages->offset[i],
             .src_len = p->page_size,
             .dst     = buf,
             /* Set dst_len to double the src in case compressed out >= page_size */
@@ -214,7 +215,7 @@ static int multifd_uadk_send_prepare(MultiFDSendParams *p, Error **errp)
          */
         if (!uadk_data->handle || creq.dst_len >= p->page_size) {
             uadk_data->buf_hdr[i] = cpu_to_be32(p->page_size);
-            prepare_next_iov(p, p->pages->block->host + p->pages->offset[i],
+            prepare_next_iov(p, pages->block->host + pages->offset[i],
                              p->page_size);
             buf += p->page_size;
         }
diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
index 2ced69487e..65f8aba5c8 100644
--- a/migration/multifd-zlib.c
+++ b/migration/multifd-zlib.c
@@ -147,7 +147,7 @@ static int zlib_send_prepare(MultiFDSendParams *p, Error **errp)
          * with compression. zlib does not guarantee that this is safe,
          * therefore copy the page before calling deflate().
          */
-        memcpy(z->buf, p->pages->block->host + pages->offset[i], p->page_size);
+        memcpy(z->buf, pages->block->host + pages->offset[i], p->page_size);
         zs->avail_in = p->page_size;
         zs->next_in = z->buf;
 
diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
index ca17b7e310..cb6075a9a5 100644
--- a/migration/multifd-zstd.c
+++ b/migration/multifd-zstd.c
@@ -138,7 +138,7 @@ static int zstd_send_prepare(MultiFDSendParams *p, Error **errp)
         if (i == pages->normal_num - 1) {
             flush = ZSTD_e_flush;
         }
-        z->in.src = p->pages->block->host + pages->offset[i];
+        z->in.src = pages->block->host + pages->offset[i];
         z->in.size = p->page_size;
         z->in.pos = 0;
 
diff --git a/migration/multifd.c b/migration/multifd.c
index d82885fdbb..506f42e124 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -114,11 +114,11 @@ static void multifd_set_file_bitmap(MultiFDSendParams *p)
 
     assert(pages->block);
 
-    for (int i = 0; i < p->pages->normal_num; i++) {
+    for (int i = 0; i < pages->normal_num; i++) {
         ramblock_set_file_bmap_atomic(pages->block, pages->offset[i], true);
     }
 
-    for (int i = p->pages->normal_num; i < p->pages->num; i++) {
+    for (int i = pages->normal_num; i < pages->num; i++) {
         ramblock_set_file_bmap_atomic(pages->block, pages->offset[i], false);
     }
 }
@@ -417,7 +417,7 @@ void multifd_send_fill_packet(MultiFDSendParams *p)
     int i;
 
     packet->flags = cpu_to_be32(p->flags);
-    packet->pages_alloc = cpu_to_be32(p->pages->allocated);
+    packet->pages_alloc = cpu_to_be32(pages->allocated);
     packet->normal_pages = cpu_to_be32(pages->normal_num);
     packet->zero_pages = cpu_to_be32(zero_num);
     packet->next_packet_size = cpu_to_be32(p->next_packet_size);
@@ -953,7 +953,7 @@ static void *multifd_send_thread(void *opaque)
 
             if (migrate_mapped_ram()) {
                 ret = file_write_ramblock_iov(p->c, p->iov, p->iovs_num,
-                                              p->pages->block, &local_err);
+                                              pages->block, &local_err);
             } else {
                 ret = qio_channel_writev_full_all(p->c, p->iov, p->iovs_num,
                                                   NULL, 0, p->write_flags,
@@ -969,7 +969,7 @@ static void *multifd_send_thread(void *opaque)
             stat64_add(&mig_stats.normal_pages, pages->normal_num);
             stat64_add(&mig_stats.zero_pages, pages->num - pages->normal_num);
 
-            multifd_pages_reset(p->pages);
+            multifd_pages_reset(pages);
             p->next_packet_size = 0;
 
             /*
@@ -1684,9 +1684,10 @@ void multifd_recv_new_channel(QIOChannel *ioc, Error **errp)
 
 bool multifd_send_prepare_common(MultiFDSendParams *p)
 {
+    MultiFDPages_t *pages = p->pages;
     multifd_send_zero_page_detect(p);
 
-    if (!p->pages->normal_num) {
+    if (!pages->normal_num) {
         p->next_packet_size = 0;
         return false;
     }
-- 
2.35.3
Re: [RFC PATCH 1/7] migration/multifd: Reduce access to p->pages
Posted by Peter Xu 5 months ago
On Thu, Jun 20, 2024 at 06:21:05PM -0300, Fabiano Rosas wrote:
> I'm about to replace the p->pages pointer with an opaque pointer, so
> do a cleanup now to reduce direct accesses to p->page, which makes the
> next diffs cleaner.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu