Improve bsrange buflen generations
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/io_u.c b/io_u.c
index 92b7076..0d24b18 100644
--- a/io_u.c
+++ b/io_u.c
@@ -77,7 +77,6 @@
else
mask = ((1U << this_blocks) - 1) << bit;
- fio_assert(td, !(f->file_map[idx] & mask));
f->file_map[idx] |= mask;
nr_blocks -= this_blocks;
blocks += this_blocks;
@@ -228,20 +227,30 @@
return 0;
}
+static inline int is_power_of_2(unsigned int val)
+{
+ return (val != 0 && ((val & (val - 1)) == 0));
+}
+
static unsigned int get_next_buflen(struct thread_data *td, struct io_u *io_u)
{
const int ddir = io_u->ddir;
unsigned int buflen = buflen; /* silence dumb gcc warning */
+ unsigned int minbs, maxbs;
long r;
- if (td->o.min_bs[ddir] == td->o.max_bs[ddir])
- buflen = td->o.min_bs[ddir];
+ minbs = td->o.min_bs[ddir];
+ maxbs = td->o.max_bs[ddir];
+
+ if (minbs == maxbs)
+ buflen = minbs;
else {
r = os_random_long(&td->bsrange_state);
if (!td->o.bssplit_nr) {
- buflen = (unsigned int)
- (1 + (double) (td->o.max_bs[ddir] - 1)
- * r / (OS_RAND_MAX + 1.0));
+ buflen = 1 + (unsigned int) ((double) maxbs *
+ (r / (OS_RAND_MAX + 1.0)));
+ if (buflen < minbs)
+ buflen = minbs;
} else {
long perc = 0;
unsigned int i;
@@ -251,20 +260,18 @@
buflen = bsp->bs;
perc += bsp->perc;
- if (r <= ((LONG_MAX / 100L) * perc))
+ if (r <= ((OS_RAND_MAX / 100L) * perc))
break;
}
}
- if (!td->o.bs_unaligned) {
- buflen = (buflen + td->o.min_bs[ddir] - 1)
- & ~(td->o.min_bs[ddir] - 1);
- }
+ if (!td->o.bs_unaligned && is_power_of_2(minbs))
+ buflen = (buflen + minbs - 1) & ~(minbs - 1);
}
if (io_u->offset + buflen > io_u->file->real_file_size) {
dprint(FD_IO, "lower buflen %u -> %u (ddir=%d)\n", buflen,
- td->o.min_bs[ddir], ddir);
- buflen = td->o.min_bs[ddir];
+ minbs, ddir);
+ buflen = minbs;
}
return buflen;