On 9/19/19 11:35 PM, Hui Zhu wrote: > This is the second version of this patch. The previous version is in > https://lkml.org/lkml/2019/9/11/935 > I updated the commit introduction and Kconfig because it is not clear. > Hi, Just a few minor fixes (below): > > Signed-off-by: Hui Zhu <teawaterz@xxxxxxxxxxxxxxxxx> > --- > include/linux/swap.h | 3 +++ > mm/Kconfig | 18 +++++++++++++++++ > mm/page_io.c | 16 +++++++++++++++ > mm/zswap.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 92 insertions(+) > > diff --git a/mm/Kconfig b/mm/Kconfig > index 56cec63..5408d65 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -546,6 +546,24 @@ config ZSWAP > they have not be fully explored on the large set of potential > configurations and workloads that exist. > > +config ZSWAP_IO_SWITCH > + bool "Compressed cache for swap pages according to the IO status" > + depends on ZSWAP > + def_bool n Just drop the "def_bool n". It's already a "bool" and 'n' is the default value for it. > + help > + This function help the system that normal swap speed is higher helps the system in which normal swap speed is higher > + than zswap speed to handle the swap IO issue. > + For example, a VM that is disk device is not set cache config or possibly: For example, a VM where the disk device is not set for cache config or > + set cache=writeback. > + > + This function make zswap just work when the disk of the swap file This function makes > + is under high IO load. > + It add two parameters read_in_flight_limit and write_in_flight_limit to It adds two parameters (read_in_flight_limit and write_in_flight_limit) to > + zswap. When zswap is enabled, pages will be stored to zswap only > + when the IO in flight number of swap device is bigger than of the swap device > + zswap_read_in_flight_limit or zswap_write_in_flight_limit. > + If unsure, say "n". > + > config ZPOOL > tristate "Common API for compressed memory storage" > help > diff --git a/mm/zswap.c b/mm/zswap.c > index 0e22744..1255645 100644 > --- a/mm/zswap.c > +++ b/mm/zswap.c > @@ -62,6 +62,13 @@ static u64 zswap_reject_compress_poor; > static u64 zswap_reject_alloc_fail; > /* Store failed because the entry metadata could not be allocated (rare) */ > static u64 zswap_reject_kmemcache_fail; > +#ifdef CONFIG_ZSWAP_IO_SWITCH > +/* Store failed because zswap_read_in_flight_limit or > + * zswap_write_in_flight_limit is bigger than IO in flight number of > + * swap device > + */ Please use the documented multi-line comment format. E.g.: /* * Store failed because zswap_read_in_flight_limit or * zswap_write_in_flight_limit is bigger than IO in flight number of * swap device. */ > +static u64 zswap_reject_io; > +#endif > /* Duplicate store was encountered (rare) */ > static u64 zswap_duplicate_entry; > > @@ -114,6 +121,22 @@ static bool zswap_same_filled_pages_enabled = true; > module_param_named(same_filled_pages_enabled, zswap_same_filled_pages_enabled, > bool, 0644); > > +#ifdef CONFIG_ZSWAP_IO_SWITCH > +/* zswap will not try to store the page if zswap_read_in_flight_limit is > + * bigger than IO read in flight number of swap device > + */ Use documented multi-line comment format. > +static unsigned int zswap_read_in_flight_limit; > +module_param_named(read_in_flight_limit, zswap_read_in_flight_limit, > + uint, 0644); > + > +/* zswap will not try to store the page if zswap_write_in_flight_limit is > + * bigger than IO write in flight number of swap device > + */ ditto. thanks. -- ~Randy
