From: Steven Rostedt Date: Wed, 25 Apr 2012 17:48:13 +0000 (-0400) Subject: ftrace: Consolidate ftrace_location() and ftrace_text_reserved() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a650e02a528ab9d6d6f0b8b57745c32f2a138459;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git ftrace: Consolidate ftrace_location() and ftrace_text_reserved() Both ftrace_location() and ftrace_text_reserved() do basically the same thing. They search to see if an address is in the ftace table (contains an address that may change from nop to call ftrace_caller). The difference is that ftrace_location() searches a single address, but ftrace_text_reserved() searches a range. This also makes the ftrace_text_reserved() faster as it now uses a bsearch() instead of linearly searching all the addresses within a page. Cc: Masami Hiramatsu Signed-off-by: Steven Rostedt --- diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index fc93562a6654..dd091c84b57f 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1383,35 +1383,28 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip) static int ftrace_cmp_recs(const void *a, const void *b) { - const struct dyn_ftrace *reca = a; - const struct dyn_ftrace *recb = b; + const struct dyn_ftrace *key = a; + const struct dyn_ftrace *rec = b; - if (reca->ip > recb->ip) - return 1; - if (reca->ip < recb->ip) + if (key->flags < rec->ip) return -1; + if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) + return 1; return 0; } -/** - * ftrace_location - return true if the ip giving is a traced location - * @ip: the instruction pointer to check - * - * Returns 1 if @ip given is a pointer to a ftrace location. - * That is, the instruction that is either a NOP or call to - * the function tracer. It checks the ftrace internal tables to - * determine if the address belongs or not. - */ -int ftrace_location(unsigned long ip) +static int ftrace_location_range(unsigned long start, unsigned long end) { struct ftrace_page *pg; struct dyn_ftrace *rec; struct dyn_ftrace key; - key.ip = ip; + key.ip = start; + key.flags = end; /* overload flags, as it is unsigned long */ for (pg = ftrace_pages_start; pg; pg = pg->next) { - if (ip < pg->records[0].ip || ip > pg->records[pg->index - 1].ip) + if (end < pg->records[0].ip || + start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) continue; rec = bsearch(&key, pg->records, pg->index, sizeof(struct dyn_ftrace), @@ -1423,6 +1416,36 @@ int ftrace_location(unsigned long ip) return 0; } +/** + * ftrace_location - return true if the ip giving is a traced location + * @ip: the instruction pointer to check + * + * Returns 1 if @ip given is a pointer to a ftrace location. + * That is, the instruction that is either a NOP or call to + * the function tracer. It checks the ftrace internal tables to + * determine if the address belongs or not. + */ +int ftrace_location(unsigned long ip) +{ + return ftrace_location_range(ip, ip); +} + +/** + * ftrace_text_reserved - return true if range contains an ftrace location + * @start: start of range to search + * @end: end of range to search (inclusive). @end points to the last byte to check. + * + * Returns 1 if @start and @end contains a ftrace location. + * That is, the instruction that is either a NOP or call to + * the function tracer. It checks the ftrace internal tables to + * determine if the address belongs or not. + */ +int ftrace_text_reserved(void *start, void *end) +{ + return ftrace_location_range((unsigned long)start, + (unsigned long)end); +} + static void __ftrace_hash_rec_update(struct ftrace_ops *ops, int filter_hash, bool inc) @@ -1571,29 +1594,6 @@ void ftrace_bug(int failed, unsigned long ip) } } - -/* Return 1 if the address range is reserved for ftrace */ -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; - - 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; -} - static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) { unsigned long flag = 0UL;