lkml.org 
[lkml]   [2015]   [May]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCHv4 00/10] add on-demand device creation
On (05/06/15 16:28), Minchan Kim wrote:
> >
> > from your logs:
> > ...
> > [ 98.756017] zram: Removed device: zram2
> > [ 98.757087] ------------[ cut here ]------------
> > ...
> >
> > locked zram_index_mutex, removed zram2, unlocked zram_index_mutex,
> > locked zram_index_mutex, attempted to create zram2: zram2 sysfs already exist.
> >
> >
> > hm... need to think. zram hot/remove is serialized.
>
> I never look at the code but I doubt others(ex, some admin process on my machine)
> holds a ref so kobj doesn't disapper yet but zram_add try to create it?
>

well, something like this is certainly happening. hm, if this is the
case, then a very quick thing I can think of is to stop re-using previously
used zram ids. add_disk() doesn't give us a chance to handle any errors and
testing for sysfs leftovers in zram_add() looks weird.


btw, do you also want me to rename zram-control sysfs handlers?
zram_add -> zram_hot_add() ? i think zram_add()/zram_remove() is just
ok.



can you please test this patch?

---

drivers/block/zram/zram_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index e6c4316..b31f0c20 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1184,7 +1184,7 @@ static int zram_add(void)
if (!zram)
return -ENOMEM;

- ret = idr_alloc(&zram_index_idr, zram, 0, 0, GFP_KERNEL);
+ ret = idr_alloc_cyclic(&zram_index_idr, zram, 0, 0, GFP_KERNEL);
if (ret < 0)
goto out_free_dev;
device_id = ret;

\
 
 \ /
  Last update: 2015-05-06 10:41    [W:0.089 / U:0.484 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site