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Subjectfs/select.c [patch > to >=]
fs/select.c (from 2.4.19 but present in 2.5.x also)

asmlinkage long sys_poll(struct pollfd * ufds, unsigned int nfds, long timeout)
{
int i, j, fdcount, err;
struct pollfd **fds;
poll_table table, *wait;
int nchunks, nleft;

[ skip ]

nchunks = 0;
nleft = nfds;
while (nleft > POLLFD_PER_PAGE) { /* allocate complete PAGE_SIZE chunks
*/
fds[nchunks] = (struct pollfd *)__get_free_page(GFP_KERNEL);
if (fds[nchunks] == NULL)
goto out_fds;
nchunks++;
nleft -= POLLFD_PER_PAGE;
}
if (nleft) { /* allocate last PAGE_SIZE chunk, only nleft elements used
*/

why not -->

while (nleft >= POLLFD_PER_PAGE) {

in this case we will use only nchunks in the case that this will end up
page aligned.. the current way of using only > POLLFD_PER_PAGE will
end up with nchunks, and nleft == PAGE_SIZE / sizeof(pollfd) etc..

silly optimisation by changing > to >=, but still an optimisation.. if there
is something obviously wrong with changing > to >=, ignore me since I
probably should get more sleep.. but I dont see any problem though I havent
really looked at it too much.

attachment has 1 line (1 character) patch ;-)

--
Silvio

diff -u fs/select.c.2.4.19 fs/select.c
--- fs/select.c.2.4.19 Tue Aug 20 17:51:48 2002
+++ fs/select.c Tue Aug 20 17:52:15 2002
@@ -445,7 +445,7 @@

nchunks = 0;
nleft = nfds;
- while (nleft > POLLFD_PER_PAGE) { /* allocate complete PAGE_SIZE chunks */
+ while (nleft >= POLLFD_PER_PAGE) { /* allocate complete PAGE_SIZE chunks */
fds[nchunks] = (struct pollfd *)__get_free_page(GFP_KERNEL);
if (fds[nchunks] == NULL)
goto out_fds;
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