From 0f133021bd82548a33580bfb7b055e8857f46c2a Mon Sep 17 00:00:00 2001 From: Daniel Bristot de Oliveira Date: Wed, 12 Jun 2019 11:57:28 +0200 Subject: 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 Signed-off-by: Peter Zijlstra (Intel) Cc: Borislav Petkov Cc: Chris von Recklinghausen Cc: Clark Williams Cc: Greg Kroah-Hartman Cc: H. Peter Anvin Cc: Jason Baron Cc: Jiri Kosina Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Marcelo Tosatti Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Scott Wood Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/f57ae83e0592418ba269866bb7ade570fc8632e0.1560325897.git.bristot@redhat.com Signed-off-by: Ingo Molnar --- kernel/jump_label.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'kernel/jump_label.c') 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; } -- cgit v1.2.3