On Fri, Dec 30, 2011 at 11:35:45AM -0600, Seth Jennings wrote: > On 12/30/2011 11:02 AM, Dan Magenheimer wrote: > >> From: Seth Jennings [mailto:sjenning@xxxxxxxxxxxxxxxxxx] > >> Sent: Friday, December 30, 2011 9:42 AM > >> To: Greg Kroah-Hartman > >> Cc: Seth Jennings; Dan Magenheimer; Brian King; devel@xxxxxxxxxxxxxxxxxxxx; linux- > >> kernel@xxxxxxxxxxxxxxx > >> Subject: [PATCH] staging: zcache: fix serialization bug in zv stats > >> > >> In a multithreaded workload, the zv_curr_dist_counts > >> and zv_cumul_dist_counts statistics are being corrupted > >> because the increments and decrements in zv_create > >> and zv_free are not atomic. > >> > >> This patch converts these statistics and their corresponding > >> increments/decrements/reads to atomic operations. > >> > >> Based on v3.2-rc7 > >> > >> Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx> > > > > I'm inclined to nack this change, at least unless inside an #ifdef DEBUG, > > I guess I didn't respond to this suggestion. We could put #ifdef DEBUG > around the updates in zv_create and zv_free and around the two sysfs > *_show functions. Kinda messy though. I guess it might not matter > if we'll be re-evaluating this whole thing soon. Perhaps also add in the TODO file that we want to move the stats collection out of the code and only be enabled if CONFIG_DEBUGFS is set? (Which granted means we need to implement the stats output in debugfs instead of sysfs). _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
