Commit-ID: 0f133021bd82548a33580bfb7b055e8857f46c2a Gitweb: https://git.kernel.org/tip/0f133021bd82548a33580bfb7b055e8857f46c2a Author: Daniel Bristot de Oliveira <[email protected]> AuthorDate: Wed, 12 Jun 2019 11:57:28 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Mon, 17 Jun 2019 12:09:21 +0200
jump_label: Sort entries of the same key by the code In the batching mode, all the entries of a given key are updated at once. During the update of a key, a hit in the int3 handler will check if the hitting code address belongs to one of these keys. To optimize the search of a given code in the vector of entries being updated, a binary search is used. The binary search relies on the order of the entries of a key by its code. Hence the keys need to be sorted by the code too, so sort the entries of a given key by the code. Signed-off-by: Daniel Bristot de Oliveira <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Chris von Recklinghausen <[email protected]> Cc: Clark Williams <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Jason Baron <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Marcelo Tosatti <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Scott Wood <[email protected]> Cc: Steven Rostedt (VMware) <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: https://lkml.kernel.org/r/f57ae83e0592418ba269866bb7ade570fc8632e0.1560325897.git.bris...@redhat.com Signed-off-by: Ingo Molnar <[email protected]> --- kernel/jump_label.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 24f0d3b1526b..ca00ac10d9b9 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -37,12 +37,26 @@ static int jump_label_cmp(const void *a, const void *b) const struct jump_entry *jea = a; const struct jump_entry *jeb = b; + /* + * Entrires are sorted by key. + */ if (jump_entry_key(jea) < jump_entry_key(jeb)) return -1; if (jump_entry_key(jea) > jump_entry_key(jeb)) return 1; + /* + * In the batching mode, entries should also be sorted by the code + * inside the already sorted list of entries, enabling a bsearch in + * the vector. + */ + if (jump_entry_code(jea) < jump_entry_code(jeb)) + return -1; + + if (jump_entry_code(jea) > jump_entry_code(jeb)) + return 1; + return 0; }
