Hi,
On 17/01/18 14:23, Bob Peterson wrote:
This patch simplifies function gfs2_rgrp_used_recently. Now it uses
ktime functions to do its calculations. Also, it's called with the
rgrp rather than the reservation, and the constant HZ rather than
the hard-coded value 1000.
Signed-off-by: Bob Peterson <[email protected]>
---
fs/gfs2/rgrp.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)
I'm not sure that this does simplify it. In any case the argument is a
time specified in msec, and HZ is a constant whose value is the number
of clock ticks in a second. It makes no sense to assign one to the other.
It would be good to get away from the constant of 1 sec that is used
here, but that required some analysis in order to figure out how to
create a suitable algorithm. If as a result of testing we can work out a
more suitable constant to use here, then that is fine as a stop gap
measure too. HZ though makes no sense at all in this case,
Steve.
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 6dea72f49316..4c9467bf9ab6 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1900,21 +1900,18 @@ static bool gfs2_rgrp_congested(const struct gfs2_rgrpd
*rgd, int loops)
}
/**
- * gfs2_rgrp_used_recently
- * @rs: The block reservation with the rgrp to test
+ * gfs2_rgrp_used_recently - check if a rgrp has been used recently
+ * @rgd: The rgrp to test
* @msecs: The time limit in milliseconds
*
* Returns: True if the rgrp glock has been used within the time limit
*/
-static bool gfs2_rgrp_used_recently(const struct gfs2_blkreserv *rs,
- u64 msecs)
+static inline bool gfs2_rgrp_used_recently(const struct gfs2_rgrpd *rgd,
+ u64 msecs)
{
- u64 tdiff;
-
- tdiff = ktime_to_ns(ktime_sub(ktime_get_real(),
- rs->rs_rbm.rgd->rd_gl->gl_dstamp));
-
- return tdiff > (msecs * 1000 * 1000);
+ return (ktime_before(ktime_get_real(),
+ ktime_add(rgd->rd_gl->gl_dstamp,
+ ms_to_ktime(msecs))));
}
static u32 gfs2_orlov_skip(const struct gfs2_inode *ip)
@@ -2014,7 +2011,7 @@ int gfs2_inplace_reserve(struct gfs2_inode *ip, struct
gfs2_alloc_parms *ap)
!fast_to_acquire(rs->rs_rbm.rgd))
goto next_rgrp;
if ((loops < 2) &&
- gfs2_rgrp_used_recently(rs, 1000) &&
+ gfs2_rgrp_used_recently(rs->rs_rbm.rgd, HZ)
&&
gfs2_rgrp_congested(rs->rs_rbm.rgd, loops))
goto next_rgrp;
}
