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path: root/fs/read_write.c
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2007-02-12[PATCH] FS: speed up rw_verify_area()Eric Dumazet
oprofile hunting showed a stall in rw_verify_area(), because of triple indirection and potential cache misses. (file->f_path.dentry->d_inode->i_flock) By moving initialization of 'struct inode' pointer before the pos/count sanity tests, we allow the compiler and processor to perform two loads by anticipation, reducing stall, without prefetch() hints. Even x86 arch has enough registers to not use temporary variables and not increase text size. I validated this patch running a bench and studied oprofile changes, and absolute perf of the test program. Results of my epoll_pipe_bench (source available on request) on a Pentium-M 1.6 GHz machine Before : # ./epoll_pipe_bench -l 30 -t 20 Avg: 436089 evts/sec read_count=8843037 write_count=8843040 21.218390 samples per call (best value out of 10 runs) After : # ./epoll_pipe_bench -l 30 -t 20 Avg: 470980 evts/sec read_count=9549871 write_count=9549894 21.216694 samples per call (best value out of 10 runs) oprofile CPU_CLK_UNHALTED events gave a reduction from 5.3401 % to 2.5851 % for the rw_verify_area() function. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] ifdef ->rchar, ->wchar, ->syscr, ->syscw from task_structAlexey Dobriyan
They are fat: 4x8 bytes in task_struct. They are uncoditionally updated in every fork, read, write and sendfile. They are used only if you have some "extended acct fields feature". And please, please, please, read(2) knows about bytes, not characters, why it is called "rchar"? Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-13[PATCH] one more EXPORT_UNUSED_SYMBOL removalAdrian Bunk
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] VFS: change struct file to use struct pathJosef "Jeff" Sipek
This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Add vector AIO supportBadari Pulavarty
This work is initially done by Zach Brown to add support for vectored aio. These are the core changes for AIO to support IOCB_CMD_PREADV/IOCB_CMD_PWRITEV. [akpm@osdl.org: huge build fix] Signed-off-by: Zach Brown <zach.brown@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Acked-by: Benjamin LaHaise <bcrl@kvack.org> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Streamline generic_file_* interfaces and filemap cleanupsBadari Pulavarty
This patch cleans up generic_file_*_read/write() interfaces. Christoph Hellwig gave me the idea for this clean ups. In a nutshell, all filesystems should set .aio_read/.aio_write methods and use do_sync_read/ do_sync_write() as their .read/.write methods. This allows us to cleanup all variants of generic_file_* routines. Final available interfaces: generic_file_aio_read() - read handler generic_file_aio_write() - write handler generic_file_aio_write_nolock() - no lock write handler __generic_file_aio_write_nolock() - internal worker routine Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Remove readv/writev methods and use aio_read/aio_write insteadBadari Pulavarty
This patch removes readv() and writev() methods and replaces them with aio_read()/aio_write() methods. Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Vectorize aio_read/aio_write fileop methodsBadari Pulavarty
This patch vectorizes aio_read() and aio_write() methods to prepare for collapsing all aio & vectored operations into one interface - which is aio_read()/aio_write(). Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Michael Holzheu <HOLZHEU@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] fs/read_write.c: EXPORT_UNUSED_SYMBOLAdrian Bunk
This patch marks an unused export as EXPORT_UNUSED_SYMBOL. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11[PATCH] splice: unlikely() optimizationsJens Axboe
Also corrects a few comments. Patch mainly from Ingo, changes by me. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-28[PATCH] Make most file operations structs in fs/ constArjan van de Ven
This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25[PATCH] remove needless check in fs/read_write.cCarsten Otte
nr_segs is unsigned long and thus cannot be negative. We checked against 0 few lines before. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-09[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_semJes Sorensen
This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-04Relax the rw_verify_area() error checking.Linus Torvalds
In particular, allow over-large read- or write-requests to be downgraded to a more reasonable range, rather than considering them outright errors. We want to protect lower layers from (the sadly all too common) overflow conditions, but prefer to do so by chopping the requests up, rather than just refusing them outright. Cc: Peter Anvin <hpa@zytor.com> Cc: Ulrich Drepper <drepper@redhat.com> Cc: Andi Kleen <ak@suse.de> Cc: Al Viro <viro@ftp.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-29[PATCH] readv/writev syscalls are not checked by lsmKostik Belousov
it seems that readv(2)/writev(2) syscalls do not call file_permission callback. Looks like this is overlook. I have filled the issue into redhat bugzilla as https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=169433 and got the recommendation to post this on lsm mailing list. The following trivial patch solves the problem. Signed-off-by: Kostik Belousov <kostikbel@gmail.com> Signed-off-by: Chris Wright <chrisw@osdl.org>
2005-09-07[PATCH] remove file.f_maxcountEric Dumazet
struct file cleanup: f_maxcount has an unique value (INT_MAX). Just use the hard-wired value. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-12[PATCH] inotifyRobert Love
inotify is intended to correct the deficiencies of dnotify, particularly its inability to scale and its terrible user interface: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a system call that returns a fd, not SIGIO. You get a single fd, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. Inotify is currently used by Beagle (a desktop search infrastructure), Gamin (a FAM replacement), and other projects. See Documentation/filesystems/inotify.txt. Signed-off-by: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] aio: fix do_sync_(read|write) to properly handle aio retriesBenjamin LaHaise
When do_sync_(read|write) encounters an aio method that makes use of the retry mechanism, they fail to correctly retry the operation. This fixes that by adding the appropriate sleep and retry mechanism. Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16[PATCH] undo do_readv_writev() behavior changeDave Hansen
Bugme bug 4326: http://bugme.osdl.org/show_bug.cgi?id=4326 reports: executing the systemcall readv with Bad argument ->len == -1) it gives out error EFAULT instead of EINVAL Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!