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path: root/include/linux/dcache.h
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2006-03-31[PATCH] dcache: Add helper d_hash_and_lookupEric W. Biederman
It is very common to hash a dentry and then to call lookup. If we take fs specific hash functions into account the full hash logic can get ugly. Further full_name_hash as an inline function is almost 100 bytes on x86 so having a non-inline choice in some cases can measurably decrease code size. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25[PATCH] inotify: lock avoidance with parent watch status in dentryNick Piggin
Previous inotify work avoidance is good when inotify is completely unused, but it breaks down if even a single watch is in place anywhere in the system. Robin Holt notices that udev is one such culprit - it slows down a 512-thread application on a 512 CPU system from 6 seconds to 22 minutes. Solve this by adding a flag in the dentry that tells inotify whether or not its parent inode has a watch on it. Event queueing to parent will skip taking locks if this flag is cleared. Setting and clearing of this flag on all child dentries versus event delivery: this is no in terms of race cases, and that was shown to be equivalent to always performing the check. The essential behaviour is that activity occuring _after_ a watch has been added and _before_ it has been removed, will generate events. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-07[PATCH] remove bogus asm/bug.h includes.Al Viro
A bunch of asm/bug.h includes are both not needed (since it will get pulled anyway) and bogus (since they are done too early). Removed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-02-03[PATCH] make "struct d_cookie" depend on CONFIG_PROFILINGMarcelo Tosatti
Shrinks "struct dentry" from 128 bytes to 124 on x86, allowing 31 objects per slab instead of 30. Cc: John Levon <levon@movementarian.org> Cc: Philippe Elie <phil.el@wanadoo.fr> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08[PATCH] shrink dentry structEric Dumazet
Some long time ago, dentry struct was carefully tuned so that on 32 bits UP, sizeof(struct dentry) was exactly 128, ie a power of 2, and a multiple of memory cache lines. Then RCU was added and dentry struct enlarged by two pointers, with nice results for SMP, but not so good on UP, because breaking the above tuning (128 + 8 = 136 bytes) This patch reverts this unwanted side effect, by using an union (d_u), where d_rcu and d_child are placed so that these two fields can share their memory needs. At the time d_free() is called (and d_rcu is really used), d_child is known to be empty and not touched by the dentry freeing. Lockless lookups only access d_name, d_parent, d_lock, d_op, d_flags (so the previous content of d_child is not needed if said dentry was unhashed but still accessed by a CPU because of RCU constraints) As dentry cache easily contains millions of entries, a size reduction is worth the extra complexity of the ugly C union. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Maneesh Soni <maneesh@in.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: Ian Kent <raven@themaw.net> Cc: Paul Jackson <pj@sgi.com> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: James Morris <jmorris@namei.org> Cc: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07[PATCH] shared mounts handling: umountRam Pai
An unmount of a mount creates a umount event on the parent. If the parent is a shared mount, it gets propagated to all mounts in the peer group. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07[PATCH] struct dentry: place d_hash close to d_parent and d_name to speedup ↵Eric Dumazet
lookups dentry cache uses sophisticated RCU technology (and prefetching if available) but touches 2 cache lines per dentry during hlist lookup. This patch moves d_hash in the same cache line than d_parent and d_name fields so that : 1) One cache line is needed instead of two. 2) the hlist_for_each_rcu() prefetching has a chance to bring all the needed data in advance, not only the part that includes d_hash.next. I also changed one old comment that was wrong for 64bits. A further optimisation would be to separate dentry in two parts, one that is mostly read, and one writen (d_count/d_lock) to avoid false sharing on SMP/NUMA but this would need different field placement depending on 32bits or 64bits platform. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-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!