From: Steven Rostedt As all records in a page of the ftrace table are sorted, we can speed up the search algorithm by checking if the address to look for falls in between the first and last record ip on the page. This speeds up both the ftrace_location() and ftrace_text_reserved() algorithms, as it can skip full pages when the search address is not in them. Cc: Masami Hiramatsu Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 4e608f8..333f890 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1411,6 +1411,8 @@ int ftrace_location(unsigned long ip) key.ip = ip; for (pg = ftrace_pages_start; pg; pg = pg->next) { + if (ip < pg->records[0].ip || ip > pg->records[pg->index - 1].ip) + continue; rec = bsearch(&key, pg->records, pg->index, sizeof(struct dyn_ftrace), ftrace_cmp_recs); @@ -1571,16 +1573,24 @@ void ftrace_bug(int failed, unsigned long ip) /* Return 1 if the address range is reserved for ftrace */ -int ftrace_text_reserved(void *start, void *end) +int ftrace_text_reserved(void *s, void *e) { struct dyn_ftrace *rec; struct ftrace_page *pg; + unsigned long start = (unsigned long)s; + unsigned long end = (unsigned long)e; + int i; - do_for_each_ftrace_rec(pg, rec) { - if (rec->ip <= (unsigned long)end && - rec->ip + MCOUNT_INSN_SIZE > (unsigned long)start) - return 1; - } while_for_each_ftrace_rec(); + for (pg = ftrace_pages_start; pg; pg = pg->next) { + if (end < pg->records[0].ip || + start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) + continue; + for (i = 0; i < pg->index; i++) { + rec = &pg->records[i]; + if (rec->ip <= end && rec->ip + MCOUNT_INSN_SIZE > start) + return 1; + } + } return 0; } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/