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]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: "Steven Rostedt (VMware)" <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: "Peter Zijlstra (Intel)" <[email protected]> Cc: Chris von Recklinghausen <[email protected]> Cc: Jason Baron <[email protected]> Cc: Scott Wood <[email protected]> Cc: Marcelo Tosatti <[email protected]> Cc: Clark Williams <[email protected]> Cc: [email protected] Cc: [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 468ca421ad9a..2bd172e1e95f 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; } -- 2.20.1
