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Squashfs: Makefiles Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> 2009-01-05 08:46:27 +00:00





Squashfs: Directly decompress into the page cache for file data This introduces an implementation of squashfs_readpage_block() that directly decompresses into the page cache. This uses the previously added page handler abstraction to push down the necessary kmap_atomic/kunmap_atomic operations on the page cache buffers into the decompressors. This enables direct copying into the page cache without using the slow kmap/kunmap calls. The code detects when multiple threads are racing in squashfs_readpage() to decompress the same block, and avoids this regression by falling back to using an intermediate buffer. This patch enhances the performance of Squashfs significantly when multiple processes are accessing the filesystem simultaneously because it not only reduces memcopying, but it more importantly eliminates the lock contention on the intermediate buffer. Using single-thread decompression. dd if=file1 of=/dev/null bs=4096 & dd if=file2 of=/dev/null bs=4096 & dd if=file3 of=/dev/null bs=4096 & dd if=file4 of=/dev/null bs=4096 Before: 629145600 bytes (629 MB) copied, 45.8046 s, 13.7 MB/s After: 629145600 bytes (629 MB) copied, 9.29414 s, 67.7 MB/s Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> Reviewed-by: Minchan Kim <minchan@kernel.org> 2013-11-13 02:04:19 +00:00


Squashfs: add multi-threaded decompression using percpu variable Add a multi-threaded decompression implementation which uses percpu variables. Using percpu variables has advantages and disadvantages over implementations which do not use percpu variables. Advantages: * the nature of percpu variables ensures decompression is load-balanced across the multiple cores. * simplicity. Disadvantages: it limits decompression to one thread per core. Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> 2013-11-18 02:31:36 +00:00


Squashfs: Make XATTR config name consistent with other file systems Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> 2010-05-31 18:46:29 +01:00
Squashfs: Add LZ4 compression configuration option Add the glue code, and also update the documentation. Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> 2014-11-27 18:48:44 +00:00
Squashfs: Add LZO compression support Signed-off-by: Chan Jeong <chan.jeong@lge.com> Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> 2010-08-05 02:29:59 +01:00
Squashfs: Add XZ compression configuration option Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> 2010-12-09 02:08:31 +00:00
Squashfs: Make ZLIB compression support optional Squashfs now supports XZ and LZO compression in addition to ZLIB. As such it no longer makes sense to always include ZLIB support. In particular embedded systems may only use LZO or XZ compression, and the ability to exclude ZLIB support will reduce kernel size. Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> 2011-07-22 03:01:28 +01:00