From b3fbd58fcbb10725a1314688e03b1af6827c42f9 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Thu, 19 May 2022 14:08:53 -0700 Subject: mm: Kconfig: simplify zswap configuration - CONFIG_ZRAM: Zram is a user-facing feature, whereas zsmalloc is not. Don't make the user chase down a technical dependency like that, just select it in automatically when zram is requested. The CONFIG_CRYPTO dependency is redundant due to more specific deps. - CONFIG_ZPOOL: This is not a user-facing feature. Hide the symbol and have it selected in as needed. - CONFIG_ZSWAP: Select CRYPTO instead of depend. Common pattern. - Make the ZSWAP suboptions and their descriptions (compression, allocation backend) a bit more straight-forward for the user. Link: https://lkml.kernel.org/r/20220510152847.230957-5-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Cc: Dan Streetman Cc: Michal Hocko Cc: Minchan Kim Cc: Roman Gushchin Cc: Seth Jennings Cc: Shakeel Butt Signed-off-by: Andrew Morton --- mm/Kconfig | 55 +++++++++++++++++++++++++------------------------------ 1 file changed, 25 insertions(+), 30 deletions(-) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index f63d8dc36511..905c205e14f3 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -9,6 +9,9 @@ menu "Memory Management options" config ARCH_NO_SWAP bool +config ZPOOL + bool + menuconfig SWAP bool "Support for paging of anonymous memory (swap)" depends on MMU && BLOCK && !ARCH_NO_SWAP @@ -21,8 +24,9 @@ menuconfig SWAP config ZSWAP bool "Compressed cache for swap pages (EXPERIMENTAL)" - depends on SWAP && CRYPTO=y + depends on SWAP select FRONTSWAP + select CRYPTO select ZPOOL help A lightweight compressed cache for swap pages. It takes @@ -38,8 +42,18 @@ config ZSWAP they have not be fully explored on the large set of potential configurations and workloads that exist. +config ZSWAP_DEFAULT_ON + bool "Enable the compressed cache for swap pages by default" + depends on ZSWAP + help + If selected, the compressed cache for swap pages will be enabled + at boot, otherwise it will be disabled. + + The selection made here can be overridden by using the kernel + command line 'zswap.enabled=' option. + choice - prompt "Compressed cache for swap pages default compressor" + prompt "Default compressor" depends on ZSWAP default ZSWAP_COMPRESSOR_DEFAULT_LZO help @@ -105,7 +119,7 @@ config ZSWAP_COMPRESSOR_DEFAULT default "" choice - prompt "Compressed cache for swap pages default allocator" + prompt "Default allocator" depends on ZSWAP default ZSWAP_ZPOOL_DEFAULT_ZBUD help @@ -145,26 +159,9 @@ config ZSWAP_ZPOOL_DEFAULT default "zsmalloc" if ZSWAP_ZPOOL_DEFAULT_ZSMALLOC default "" -config ZSWAP_DEFAULT_ON - bool "Enable the compressed cache for swap pages by default" - depends on ZSWAP - help - If selected, the compressed cache for swap pages will be enabled - at boot, otherwise it will be disabled. - - The selection made here can be overridden by using the kernel - command line 'zswap.enabled=' option. - -config ZPOOL - tristate "Common API for compressed memory storage" - depends on ZSWAP - help - Compressed memory storage API. This allows using either zbud or - zsmalloc. - config ZBUD - tristate "Low (Up to 2x) density storage for compressed pages" - depends on ZPOOL + tristate "2:1 compression allocator (zbud)" + depends on ZSWAP help A special purpose allocator for storing compressed pages. It is designed to store up to two compressed pages per physical @@ -173,8 +170,8 @@ config ZBUD density approach when reclaim will be used. config Z3FOLD - tristate "Up to 3x density storage for compressed pages" - depends on ZPOOL + tristate "3:1 compression allocator (z3fold)" + depends on ZSWAP help A special purpose allocator for storing compressed pages. It is designed to store up to three compressed pages per physical @@ -182,15 +179,13 @@ config Z3FOLD still there. config ZSMALLOC - tristate "Memory allocator for compressed pages" + tristate + prompt "N:1 compression allocator (zsmalloc)" if ZSWAP depends on MMU help zsmalloc is a slab-based memory allocator designed to store - compressed RAM pages. zsmalloc uses virtual memory mapping - in order to reduce fragmentation. However, this results in a - non-standard allocator interface where a handle, not a pointer, is - returned by an alloc(). This handle must be mapped in order to - access the allocated space. + pages of various compression levels efficiently. It achieves + the highest storage density with the least amount of fragmentation. config ZSMALLOC_STAT bool "Export zsmalloc statistics" -- cgit v1.2.3