kernel/git - git - PowerEL Git System

Author	SHA1	Message	Date
Linus Torvalds	4651ece854	Switch over tree descriptors to contain a pre-parsed entry This makes the tree descriptor contain a "struct name_entry" as part of it, and it gets filled in so that it always contains a valid entry. On some benchmarks, it improves performance by up to 15%. That makes tree entry "extract" trivial, and means that we only actually need to decode each tree entry just once: we decode the first one when we initialize the tree descriptor, and each subsequent one when doing "update_tree_entry()". In particular, this means that we don't need to do strlen() both at extract time _and_ at update time. Finally, it also allows more sharing of code (entry_extract(), that wanted a "struct name_entry", just got totally trivial, along with the "tree_entry()" function). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Linus Torvalds	6fda5e5180	Initialize tree descriptors with a helper function rather than by hand. This removes slightly more lines than it adds, but the real reason for doing this is that future optimizations will require more setup of the tree descriptor, and so we want to do it in one place. Also renamed the "desc.buf" field to "desc.buffer" just to trigger compiler errors for old-style manual initializations, making sure I didn't miss anything. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Linus Torvalds	a8c40471ab	Remove "pathlen" from "struct name_entry" Since we have the "tree_entry_len()" helper function these days, and don't need to do a full strlen(), there's no point in saving the path length - it's just redundant information. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Linus Torvalds	304de2d2d6	Avoid unnecessary strlen() calls This is a micro-optimization that grew out of the mailing list discussion about "strlen()" showing up in profiles. We used to pass regular C strings around to the low-level tree walking routines, and while this worked fine, it meant that we needed to call strlen() on strings that the caller always actually knew the size of anyway. So pass the length of the string down wih the string, and avoid unnecessary calls to strlen(). Also, when extracting a pathname from a tree entry, use "tree_entry_len()" instead of strlen(), since the length of the pathname is directly calculable from the decoded tree entry itself without having to actually do another strlen(). This shaves off another ~5-10% from some loads that are very tree intensive (notably doing commit filtering by a pathspec). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>" Signed-off-by: Junio C Hamano <junkio@cox.net>	18 years ago
Linus Torvalds	4c068a9831	tree_entry(): new tree-walking helper function This adds a "tree_entry()" function that combines the common operation of doing a "tree_entry_extract()" + "update_tree_entry()". It also has a simplified calling convention, designed for simple loops that traverse over a whole tree: the arguments are pointers to the tree descriptor and a name_entry structure to fill in, and it returns a boolean "true" if there was an entry left to be gotten in the tree. This allows tree traversal with struct tree_desc desc; struct name_entry entry; desc.buf = tree->buffer; desc.size = tree->size; while (tree_entry(&desc, &entry) { ... use "entry.{path, sha1, mode, pathlen}" ... } which is not only shorter than writing it out in full, it's hopefully less error prone too. [ It's actually a tad faster too - we don't need to recalculate the entry pathlength in both extract and update, but need to do it only once. Also, some callers can avoid doing a "strlen()" on the result, since it's returned as part of the name_entry structure. However, by now we're talking just 1% speedup on "git-rev-list --objects --all", and we're definitely at the point where tree walking is no longer the issue any more. ] NOTE! Not everybody wants to use this new helper function, since some of the tree walkers very much on purpose do the descriptor update separately from the entry extraction. So the "extract + update" sequence still remains as the core sequence, this is just a simplified interface. We should probably add a silly two-line inline helper function for initializing the descriptor from the "struct tree" too, just to cut down on the noise from that common "desc" initializer. Signed-off-by: Linus Torvalds <torvalds@osdl.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	19 years ago
Junio C Hamano	4dcff634e6	get_tree_entry(): make it available from tree-walk Signed-off-by: Junio C Hamano <junkio@cox.net>	19 years ago
Junio C Hamano	1b0c7174a1	tree/diff header cleanup. Introduce tree-walk.[ch] and move "struct tree_desc" and associated functions from various places. Rename DIFF_FILE_CANON_MODE(mode) macro to canon_mode(mode) and move it to cache.h. This macro returns the canonicalized st_mode value in the host byte order for files, symlinks and directories -- to be compared with a tree_desc entry. create_ce_mode(mode) in cache.h is similar but is intended to be used for index entries (so it does not work for directories) and returns the value in the network byte order. Signed-off-by: Junio C Hamano <junkio@cox.net>	19 years ago