On Thu, Jan 24, 2019 at 01:17:18AM -0500, Chris Down wrote: > memcg has a significant number of files exposed to kernfs where their > value is either exposed directly or is "max" in the case of > PAGE_COUNTER_MAX. > > There's a fair amount of duplicated code here, since each file involves > turning a seq_file to a css, getting the memcg from the css, safely > reading the counter value, and then doing the right thing depending on > whether the value is PAGE_COUNTER_MAX or not. > > This patch adds the macro DEFINE_MEMCG_MAX_OR_VAL, which defines and > implements a generic way to do this work, avoiding fragmenting logic. > > Signed-off-by: Chris Down <[email protected]> > Cc: Andrew Morton <[email protected]> > Cc: Johannes Weiner <[email protected]> > Cc: Tejun Heo <[email protected]> > Cc: Roman Gushchin <[email protected]> > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > Cc: [email protected] > --- > mm/memcontrol.c | 78 ++++++++++++------------------------------------- > 1 file changed, 18 insertions(+), 60 deletions(-)
I think this increases complexity more than it saves LOC, unfortunately. The current situation is a bit repetitive, but much more obviously correct. And we're not planning on adding many more of those memcg interface files, so I this doesn't seem to be an improvement re: maintainability and future extensibility of the code.
