Changes in Kconfig

9f3310cc - zram: ZRAM_DEF_COMP should depend on ZRAM

Tue, 05 Nov 2024 11:50:35 +0000

zram: ZRAM_DEF_COMP should depend on ZRAMWhen Compressed RAM block device support is disabled, theCONFIG_ZRAM_DEF_COMP symbol still ends up in the generated config file: CONFIG_ZRAM_DEF_COMP="unset-value"While this causes no real harm, avoid polluting the config file byadding a dependency on ZRAM.Link: https://lkml.kernel.org/r/64e05bad68a9bd5cc322efd114a04d25de525940.1730807319.git.geert@linux-m68k.orgFixes: 917a59e81c34 ("zram: introduce custom comp backends API")Signed-off-by: Geert Uytterhoeven Reviewed-by: Sergey Senozhatsky Cc: Jens Axboe Cc: Minchan Kim Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

1a78390d - zram: check that backends array has at least one backend

Mon, 02 Sep 2024 10:56:00 +0000

zram: check that backends array has at least one backendMake sure that backends array has anything apart from the sentinel NULLvalue.We also select LZO_BACKEND if none backends were selected.Link: https://lkml.kernel.org/r/20240902105656.1383858-13-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

1d3100cf - zram: add 842 compression backend support

Mon, 02 Sep 2024 10:55:59 +0000

zram: add 842 compression backend supportAdd s/w 842 compression support.Link: https://lkml.kernel.org/r/20240902105656.1383858-12-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

84112e31 - zram: add zlib compression backend support

Mon, 02 Sep 2024 10:55:58 +0000

zram: add zlib compression backend supportAdd s/w zlib (inflate/deflate) compression.Link: https://lkml.kernel.org/r/20240902105656.1383858-11-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

73e7d81a - zram: add zstd compression backend support

Mon, 02 Sep 2024 10:55:56 +0000

zram: add zstd compression backend supportAdd s/w zstd compression.Link: https://lkml.kernel.org/r/20240902105656.1383858-9-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

c60a4ef5 - zram: add lz4hc compression backend support

Mon, 02 Sep 2024 10:55:55 +0000

zram: add lz4hc compression backend supportAdd s/w lz4hc compression support.Link: https://lkml.kernel.org/r/20240902105656.1383858-8-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

22d651c3 - zram: add lz4 compression backend support

Mon, 02 Sep 2024 10:55:54 +0000

zram: add lz4 compression backend supportAdd s/w lz4 compression support.Link: https://lkml.kernel.org/r/20240902105656.1383858-7-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

2152247c - zram: add lzo and lzorle compression backends support

Mon, 02 Sep 2024 10:55:53 +0000

zram: add lzo and lzorle compression backends supportAdd s/w lzo/lzorle compression support.Link: https://lkml.kernel.org/r/20240902105656.1383858-6-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

917a59e8 - zram: introduce custom comp backends API

Mon, 02 Sep 2024 10:55:52 +0000

zram: introduce custom comp backends APIMoving to custom backends implementation gives us ability to have our ownminimalistic and extendable API, and algorithms tunings becomes possible.The list of compression backends is empty at this point, we will addbackends in the followup patches.Link: https://lkml.kernel.org/r/20240902105656.1383858-5-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nick Terrell Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

04cb7502 - zsmalloc: use all available 24 bits of page_type

Wed, 21 Aug 2024 17:39:12 +0000

zsmalloc: use all available 24 bits of page_typeNow that we have an extra 8 bits, we don't need to limit ourselves tosupporting a 64KiB page size. I'm sure both Hexagon users are grateful,but it does reduce complexity a little. We can also removereset_first_obj_offset() as calling __ClearPageZsmalloc() will now resetall 32 bits of page_type.Link: https://lkml.kernel.org/r/20240821173914.2270383-5-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) Acked-by: David Hildenbrand Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>Cc: Kent Overstreet Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

43d746dc - mm/zsmalloc: use a proper page type

Wed, 29 May 2024 11:19:01 +0000

mm/zsmalloc: use a proper page typeLet's clean it up: use a proper page type and store our data (offset intoa page) in the lower 16 bit as documented.We won't be able to support 256 KiB base pages, which is acceptable. Teach Kconfig to handle that cleanly using a new CONFIG_HAVE_ZSMALLOC.Based on this, we should do a proper "struct zsdesc" conversion, asproposed in [1].This removes the last _mapcount/page_type offender.[1] https://lore.kernel.org/all/20231130101242.2590384-1-42.hyeyoo@gmail.com/Link: https://lkml.kernel.org/r/20240529111904.2069608-4-david@redhat.comSigned-off-by: David Hildenbrand Tested-by: Sergey Senozhatsky [zram/zsmalloc workloads]Reviewed-by: Sergey Senozhatsky Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>Cc: Matthew Wilcox (Oracle) Cc: Mike Rapoport (IBM) Cc: Minchan Kim Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

2e16898d - zram: tweak writeback config help

Wed, 15 Nov 2023 02:42:13 +0000

zram: tweak writeback config helpWriteback is for incompressible and idle zram pages.Link: https://lkml.kernel.org/r/20231115024223.4133148-2-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Dmytro Maluka Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

a7a03505 - zram: split memory-tracking and ac-time tracking

Wed, 15 Nov 2023 02:42:12 +0000

zram: split memory-tracking and ac-time trackingZRAM_MEMORY_TRACKING enables two features:- per-entry ac-time tracking- debugfs interfaceThe latter one is the reason why memory-tracking depends on DEBUG_FS,while the former one is used far beyond debugging these days. Namelyac-time is used for fine grained writeback of idle entries (pages).Move ac-time tracking under its own config option so that it can beenabled (along with writeback) on systems without DEBUG_FS.[senozhatsky@chromium.org: ifdef fixup, per Dmytro] Link: https://lkml.kernel.org/r/20231117013543.540280-1-senozhatsky@chromium.orgLink: https://lkml.kernel.org/r/20231115024223.4133148-1-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Dmytro Maluka Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

84b33bf7 - zram: introduce recompress sysfs knob

Wed, 09 Nov 2022 11:50:38 +0000

zram: introduce recompress sysfs knobAllow zram to recompress (using secondary compression streams)pages.Re-compression algorithms (we support up to 3 at this stage)are selected via recomp_algorithm: echo "algo=zstd priority=1" > /sys/block/zramX/recomp_algorithmPlease read documentation for more details.We support several recompression modes:1) IDLE pages recompression is activated by `idle` mode echo "type=idle" > /sys/block/zram0/recompress2) Since there may be many idle pages user-space may pass a sizethreshold value (in bytes) and we will recompress pages onlyof equal or greater size: echo "threshold=888" > /sys/block/zram0/recompress3) HUGE pages recompression is activated by `huge` mode echo "type=huge" > /sys/block/zram0/recompress4) HUGE_IDLE pages recompression is activated by `huge_idle` mode echo "type=huge_idle" > /sys/block/zram0/recompress[senozhatsky@chromium.org: we should always zero out err variable in recompress loop[ Link: https://lkml.kernel.org/r/20221110143423.3250790-1-senozhatsky@chromium.orgLink: https://lkml.kernel.org/r/20221109115047.2921851-5-senozhatsky@chromium.orgSigned-off-by: Sergey Senozhatsky Acked-by: Minchan Kim Cc: Nathan Chancellor Cc: Alexey Romanov Cc: Nhat Pham Cc: Nitin Gupta Cc: Suleiman Souhlal Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

6140ae41 - zram: fix Kconfig dependency warning

Sun, 22 May 2022 20:40:27 +0000

zram: fix Kconfig dependency warningZSMALLOC depends on MMU so ZRAM should also depend on MMU since 'select'does not follow any dependency chains.Fixes this Kconfig warning:WARNING: unmet direct dependencies detected for ZSMALLOC Depends on [n]: MMU [=n] Selected by [y]: - ZRAM [=y] && BLK_DEV [=y] && BLOCK [=y] && SYSFS [=y] && (CRYPTO_LZO [=y] || CRYPTO_ZSTD [=m] || CRYPTO_LZ4 [=m] || CRYPTO_LZ4HC [=n] || CRYPTO_842 [=n])Link: https://lkml.kernel.org/r/20220522204027.22964-1-rdunlap@infradead.orgFixes: b3fbd58fcbb10 ("mm: Kconfig: simplify zswap configuration")Signed-off-by: Randy Dunlap Acked-by: Johannes Weiner Cc: Minchan Kim Cc: Nitin Gupta Cc: Sergey Senozhatsky Cc: Jens Axboe Signed-off-by: Andrew Morton List of files: /linux-6.15/drivers/block/zram/Kconfig

b3fbd58f - mm: Kconfig: simplify zswap configuration

Thu, 19 May 2022 21:08:53 +0000

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.orgSigned-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 List of files: /linux-6.15/drivers/block/zram/Kconfig

3d711a38 - zram: break the strict dependency from lzo

Tue, 15 Dec 2020 03:14:35 +0000

zram: break the strict dependency from lzoFrom the beginning, the zram block device always enabled CRYPTO_LZO,since lzo-rle is hardcoded as the fallback compression algorithm. As aconsequence, on systems where another compression algorithm is chosen(e.g. CRYPTO_ZSTD), the lzo kernel module becomes unused, while stillhaving to be built/loaded.This patch removes the hardcoded lzo-rle dependency and allows the userto select the default compression algorithm for zram at build time. Theprevious behaviour is kept, as the default algorithm is still lzo-rle.Link: https://lkml.kernel.org/r/20201207121245.50529-1-rsalvaterra@gmail.comSigned-off-by: Rui Salvaterra Suggested-by: Sergey Senozhatsky Suggested-by: Minchan Kim Acked-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds List of files: /linux-6.15/drivers/block/zram/Kconfig

e7751617 - docs: blockdev: add it to the admin-guide

Tue, 18 Jun 2019 14:47:10 +0000

docs: blockdev: add it to the admin-guideThe blockdev book basically contains user-faced documentation.Signed-off-by: Mauro Carvalho Chehab List of files: /linux-6.15/drivers/block/zram/Kconfig

39443104 - docs: blockdev: convert to ReST

Thu, 18 Apr 2019 20:29:24 +0000

docs: blockdev: convert to ReSTRename the blockdev documentation files to ReST, add anindex for them and adjust in order to produce a nice htmloutput via the Sphinx build system.The drbd sub-directory contains some graphs and data flows.Add those too to the documentation.At its new index.rst, let's add a :orphan: while this is not linked tothe main index.rst file, in order to avoid build warnings.Signed-off-by: Mauro Carvalho Chehab List of files: /linux-6.15/drivers/block/zram/Kconfig

a939888e - zram: support idle/huge page writeback

Fri, 28 Dec 2018 08:36:47 +0000

zram: support idle/huge page writebackAdd a new feature "zram idle/huge page writeback". In the zram-swap usecase, zram usually has many idle/huge swap pages. It's pointless to keepthem in memory (ie, zram).To solve this problem, this feature introduces idle/huge page writeback tothe backing device so the goal is to save more memory space on embeddedsystems.Normal sequence to use idle/huge page writeback feature is as follows,while (1) { # mark allocated zram slot to idle echo all > /sys/block/zram0/idle # leave system working for several hours # Unless there is no access for some blocks on zram, # they are still IDLE marked pages. echo "idle" > /sys/block/zram0/writeback or/and echo "huge" > /sys/block/zram0/writeback # write the IDLE or/and huge marked slot into backing device # and free the memory.}Per the discussion athttps://lore.kernel.org/lkml/20181122065926.GG3441@jagdpanzerIV/T/#u,This patch removes direct incommpressibe page writeback feature(d2afd25114f4 ("zram: write incompressible pages to backing device")).Below concerns from Sergey:== &< =="IDLE writeback" is superior to "incompressible writeback"."incompressible writeback" is completely unpredictable and uncontrollable;it depens on data patterns and compression algorithms. While "IDLEwriteback" is predictable.I even suspect, that, *ideally*, we can remove "incompressible writeback"."IDLE pages" is a super set which also includes "incompressible" pages.So, technically, we still can do "incompressible writeback" from "IDLEwriteback" path; but a much more reasonable one, based on a page idlingperiod.I understand that you want to keep "direct incompressible writeback"around. ZRAM is especially popular on devices which do suffer from flashwearout, so I can see "incompressible writeback" path becoming a deadcode, long term.== &< ==Below concerns from Minchan:== &< ==My concern is if we enable CONFIG_ZRAM_WRITEBACK in this implementation,both hugepage/idlepage writeck will turn on. However someuser want toenable only idlepage writeback so we need to introduce turn on/off knobfor hugepage or new CONFIG_ZRAM_IDLEPAGE_WRITEBACK for those usecase. Idon't want to make it complicated *if possible*.Long term, I imagine we need to make VM aware of new swap hierarchy alittle bit different with as-is. For example, first high priority swapcan return -EIO or -ENOCOMP, swap try to fallback to next lower priorityswap device. With that, hugepage writeback will work tranparently.So we could regard it as regression because incompressible pages doesn'tgo to backing storage automatically. Instead, user should do it via "echohuge" > /sys/block/zram/writeback" manually.== &< ==Link: http://lkml.kernel.org/r/20181127055429.251614-6-minchan@kernel.orgSigned-off-by: Minchan Kim Reviewed-by: Joey Pabalinas Reviewed-by: Sergey Senozhatsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds List of files: /linux-6.15/drivers/block/zram/Kconfig