leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

libceph: use local variables for message positions

Browse Source 
There are several places where a message's out_msg_pos or in_msg_pos
field is used repeatedly within a function.  Use a local pointer
variable for this purpose to unclutter the code.

This and the upcoming cleanup patches are related to:
    http://tracker.ceph.com/issues/4403

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
This commit is contained in:
Alex Elder 2013-03-06 23:39:38 -06:00 committed by Sage Weil
parent 98a0370898
commit bae6acd9c6
1 changed files with 46 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

85
net/ceph/messenger.c
View File

@ -725,22 +725,23 @@ static void iter_bio_next(struct bio **bio_iter, unsigned int *seg)
static void prepare_write_message_data(struct ceph_connection *con)
{
struct ceph_msg *msg = con->out_msg;
struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
BUG_ON(!msg);
BUG_ON(!msg->hdr.data_len);
/* initialize page iterator */
con->out_msg_pos.page = 0;
msg_pos->page = 0;
if (msg->pages)
con->out_msg_pos.page_pos = msg->page_alignment;
msg_pos->page_pos = msg->page_alignment;
else
con->out_msg_pos.page_pos = 0;
msg_pos->page_pos = 0;
#ifdef CONFIG_BLOCK
if (msg->bio)
init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
#endif
con->out_msg_pos.data_pos = 0;
con->out_msg_pos.did_page_crc = false;
msg_pos->data_pos = 0;
msg_pos->did_page_crc = false;
con->out_more = 1; /* data + footer will follow */
}
@ -1022,19 +1023,20 @@ static void out_msg_pos_next(struct ceph_connection *con, struct page *page,
size_t len, size_t sent, bool in_trail)
{
struct ceph_msg *msg = con->out_msg;
struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
BUG_ON(!msg);
BUG_ON(!sent);
con->out_msg_pos.data_pos += sent;
con->out_msg_pos.page_pos += sent;
msg_pos->data_pos += sent;
msg_pos->page_pos += sent;
if (sent < len)
return;
BUG_ON(sent != len);
con->out_msg_pos.page_pos = 0;
con->out_msg_pos.page++;
con->out_msg_pos.did_page_crc = false;
msg_pos->page_pos = 0;
msg_pos->page++;
msg_pos->did_page_crc = false;
if (in_trail)
list_rotate_left(&msg->trail->head);
else if (msg->pagelist)
@ -1049,18 +1051,19 @@ static void in_msg_pos_next(struct ceph_connection *con, size_t len,
size_t received)
{
struct ceph_msg *msg = con->in_msg;
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
BUG_ON(!msg);
BUG_ON(!received);
con->in_msg_pos.data_pos += received;
con->in_msg_pos.page_pos += received;
msg_pos->data_pos += received;
msg_pos->page_pos += received;
if (received < len)
return;
BUG_ON(received != len);
con->in_msg_pos.page_pos = 0;
con->in_msg_pos.page++;
msg_pos->page_pos = 0;
msg_pos->page++;
#ifdef CONFIG_BLOCK
if (msg->bio)
iter_bio_next(&msg->bio_iter, &msg->bio_seg);
@ -1077,6 +1080,7 @@ static void in_msg_pos_next(struct ceph_connection *con, size_t len,
static int write_partial_msg_pages(struct ceph_connection *con)
{
struct ceph_msg *msg = con->out_msg;
struct ceph_msg_pos *msg_pos = &con->out_msg_pos;
unsigned int data_len = le32_to_cpu(msg->hdr.data_len);
size_t len;
bool do_datacrc = !con->msgr->nocrc;
@ -1087,7 +1091,7 @@ static int write_partial_msg_pages(struct ceph_connection *con)
const size_t trail_off = data_len - trail_len;
dout("write_partial_msg_pages %p msg %p page %d offset %d\n",
con, msg, con->out_msg_pos.page, con->out_msg_pos.page_pos);
con, msg, msg_pos->page, msg_pos->page_pos);
/*
* Iterate through each page that contains data to be
@ -1097,22 +1101,22 @@ static int write_partial_msg_pages(struct ceph_connection *con)
* need to map the page. If we have no pages, they have
* been revoked, so use the zero page.
*/
while (data_len > con->out_msg_pos.data_pos) {
while (data_len > msg_pos->data_pos) {
struct page *page = NULL;
int max_write = PAGE_SIZE;
int bio_offset = 0;
in_trail = in_trail || con->out_msg_pos.data_pos >= trail_off;
in_trail = in_trail || msg_pos->data_pos >= trail_off;
if (!in_trail)
total_max_write = trail_off - con->out_msg_pos.data_pos;
total_max_write = trail_off - msg_pos->data_pos;
if (in_trail) {
total_max_write = data_len - con->out_msg_pos.data_pos;
total_max_write = data_len - msg_pos->data_pos;
page = list_first_entry(&msg->trail->head,
struct page, lru);
} else if (msg->pages) {
page = msg->pages[con->out_msg_pos.page];
page = msg->pages[msg_pos->page];
} else if (msg->pagelist) {
page = list_first_entry(&msg->pagelist->head,
struct page, lru);
@ -1128,24 +1132,24 @@ static int write_partial_msg_pages(struct ceph_connection *con)
} else {
page = zero_page;
}
len = min_t(int, max_write - con->out_msg_pos.page_pos,
len = min_t(int, max_write - msg_pos->page_pos,
total_max_write);
if (do_datacrc && !con->out_msg_pos.did_page_crc) {
if (do_datacrc && !msg_pos->did_page_crc) {
void *base;
u32 crc = le32_to_cpu(msg->footer.data_crc);
char *kaddr;
kaddr = kmap(page);
BUG_ON(kaddr == NULL);
base = kaddr + con->out_msg_pos.page_pos + bio_offset;
base = kaddr + msg_pos->page_pos + bio_offset;
crc = crc32c(crc, base, len);
kunmap(page);
msg->footer.data_crc = cpu_to_le32(crc);
con->out_msg_pos.did_page_crc = true;
msg_pos->did_page_crc = true;
}
ret = ceph_tcp_sendpage(con->sock, page,
con->out_msg_pos.page_pos + bio_offset,
msg_pos->page_pos + bio_offset,
len, true);
if (ret <= 0)
goto out;
@ -1803,22 +1807,23 @@ static int read_partial_message_pages(struct ceph_connection *con,
struct page **pages,
unsigned int data_len, bool do_datacrc)
{
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
struct page *page;
void *p;
int ret;
int left;
left = min((int)(data_len - con->in_msg_pos.data_pos),
(int)(PAGE_SIZE - con->in_msg_pos.page_pos));
left = min((int)(data_len - msg_pos->data_pos),
(int)(PAGE_SIZE - msg_pos->page_pos));
/* (page) data */
BUG_ON(pages == NULL);
page = pages[con->in_msg_pos.page];
page = pages[msg_pos->page];
p = kmap(page);
ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos, left);
ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
if (ret > 0 && do_datacrc)
con->in_data_crc =
crc32c(con->in_data_crc,
p + con->in_msg_pos.page_pos, ret);
p + msg_pos->page_pos, ret);
kunmap(page);
if (ret <= 0)
return ret;
@ -1833,6 +1838,7 @@ static int read_partial_message_bio(struct ceph_connection *con,
unsigned int data_len, bool do_datacrc)
{
struct ceph_msg *msg = con->in_msg;
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
struct bio_vec *bv;
struct page *page;
void *p;
@ -1842,17 +1848,17 @@ static int read_partial_message_bio(struct ceph_connection *con,
BUG_ON(!msg->bio_iter);
bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
left = min((int)(data_len - con->in_msg_pos.data_pos),
(int)(bv->bv_len - con->in_msg_pos.page_pos));
left = min((int)(data_len - msg_pos->data_pos),
(int)(bv->bv_len - msg_pos->page_pos));
page = bv->bv_page;
p = kmap(page) + bv->bv_offset;
ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos, left);
ret = ceph_tcp_recvmsg(con->sock, p + msg_pos->page_pos, left);
if (ret > 0 && do_datacrc)
con->in_data_crc =
crc32c(con->in_data_crc,
p + con->in_msg_pos.page_pos, ret);
p + msg_pos->page_pos, ret);
kunmap(page);
if (ret <= 0)
return ret;
@ -1869,6 +1875,7 @@ static int read_partial_message_bio(struct ceph_connection *con,
static int read_partial_message(struct ceph_connection *con)
{
struct ceph_msg *m = con->in_msg;
struct ceph_msg_pos *msg_pos = &con->in_msg_pos;
int size;
int end;
int ret;
@ -1949,12 +1956,12 @@ static int read_partial_message(struct ceph_connection *con)
if (m->middle)
m->middle->vec.iov_len = 0;
con->in_msg_pos.page = 0;
msg_pos->page = 0;
if (m->pages)
con->in_msg_pos.page_pos = m->page_alignment;
msg_pos->page_pos = m->page_alignment;
else
con->in_msg_pos.page_pos = 0;
con->in_msg_pos.data_pos = 0;
msg_pos->page_pos = 0;
msg_pos->data_pos = 0;
#ifdef CONFIG_BLOCK
if (m->bio)
@ -1978,7 +1985,7 @@ static int read_partial_message(struct ceph_connection *con)
}
/* (page) data */
while (con->in_msg_pos.data_pos < data_len) {
while (msg_pos->data_pos < data_len) {
if (m->pages) {
ret = read_partial_message_pages(con, m->pages,
data_len, do_datacrc);