> From: Greg KH [mailto:gregkh@xxxxxxxxxxxxxxxxxxx] > Subject: Re: [PATCH 2/2] staging: zcache: optional support for zsmalloc as alternate allocator > > On Wed, Jan 23, 2013 at 01:46:31PM -0800, Dan Magenheimer wrote: > > "New" zcache uses zbud for all sub-page allocation which is more flexible but > > results in lower density. "Old" zcache supported zsmalloc for frontswap > > pages. Add zsmalloc to "new" zcache as a compile-time and run-time option > > for backwards compatibility in case any users wants to use zcache with > > highest possible density. > > > > Note that most of the zsmalloc stats in old zcache are not included here > > because old zcache used sysfs and new zcache has converted to debugfs. > > These stats may be added later. > > > > Note also that ramster is incompatible with zsmalloc as the two use > > the least significant bits in a pampd differently. > > > > Signed-off-by: Dan Magenheimer <dan.magenheimer@xxxxxxxxxx> > > --- > > drivers/staging/zcache/Kconfig | 11 ++ > > drivers/staging/zcache/zcache-main.c | 210 ++++++++++++++++++++++++++++++++-- > > drivers/staging/zcache/zcache.h | 3 + > > 3 files changed, 215 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/staging/zcache/Kconfig b/drivers/staging/zcache/Kconfig > > index c1dbd04..116f8d5 100644 > > --- a/drivers/staging/zcache/Kconfig > > +++ b/drivers/staging/zcache/Kconfig > > @@ -10,6 +10,17 @@ config ZCACHE > > memory to store clean page cache pages and swap in RAM, > > providing a noticeable reduction in disk I/O. > > > > +config ZCACHE_ZSMALLOC > > + bool "Allow use of zsmalloc allocator for compression of swap pages" > > + depends on ZSMALLOC=y && !RAMSTER > > + default n > > + help > > + Zsmalloc is a much more efficient allocator for compresssed > > + pages but currently has some design deficiencies in that it > > + does not support reclaim nor compaction. Select this if > > + you are certain your workload will fit or has mostly short > > + running processes. Zsmalloc is incompatible with RAMster. > > How can anyone be "certain"? > > > > --- a/drivers/staging/zcache/zcache-main.c > > +++ b/drivers/staging/zcache/zcache-main.c > > @@ -26,6 +26,12 @@ > > #include <linux/cleancache.h> > > #include <linux/frontswap.h> > > #include "tmem.h" > > +#ifdef CONFIG_ZCACHE_ZSMALLOC > > +#include "../zsmalloc/zsmalloc.h" > > Don't #ifdef .h files in .c files. > > > +static int zsmalloc_enabled; > > +#else > > +#define zsmalloc_enabled 0 > > +#endif > > That should have been your only ifdef in this .c file, all of the ones > you have after this should not be needed, so I can't take this patch, > sorry. Yep. Sorry, I was just trying to refresh this from when I posted the proof-of-concept last summer. I should have spent more time cleaning it up. Will be away for a few days so will try to repost in a week or two, hopefully not too late for this cycle. Sorry for the noise. Dan _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
