diff options
Diffstat (limited to 'include/linux/trace_recursion.h')
-rw-r--r-- | include/linux/trace_recursion.h | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/include/linux/trace_recursion.h b/include/linux/trace_recursion.h index ac3d73484cb2..228cc56ed66e 100644 --- a/include/linux/trace_recursion.h +++ b/include/linux/trace_recursion.h @@ -91,6 +91,9 @@ enum { * not be correct. Allow for a single recursion to cover this case. */ TRACE_TRANSITION_BIT, + + /* Used to prevent recursion recording from recursing. */ + TRACE_RECORD_RECURSION_BIT, }; #define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0) @@ -142,7 +145,22 @@ static __always_inline int trace_get_context_bit(void) pc & HARDIRQ_MASK ? TRACE_CTX_IRQ : TRACE_CTX_SOFTIRQ; } -static __always_inline int trace_test_and_set_recursion(int start, int max) +#ifdef CONFIG_FTRACE_RECORD_RECURSION +extern void ftrace_record_recursion(unsigned long ip, unsigned long parent_ip); +# define do_ftrace_record_recursion(ip, pip) \ + do { \ + if (!trace_recursion_test(TRACE_RECORD_RECURSION_BIT)) { \ + trace_recursion_set(TRACE_RECORD_RECURSION_BIT); \ + ftrace_record_recursion(ip, pip); \ + trace_recursion_clear(TRACE_RECORD_RECURSION_BIT); \ + } \ + } while (0) +#else +# define do_ftrace_record_recursion(ip, pip) do { } while (0) +#endif + +static __always_inline int trace_test_and_set_recursion(unsigned long ip, unsigned long pip, + int start, int max) { unsigned int val = current->trace_recursion; int bit; @@ -158,8 +176,10 @@ static __always_inline int trace_test_and_set_recursion(int start, int max) * a switch between contexts. Allow for a single recursion. */ bit = TRACE_TRANSITION_BIT; - if (trace_recursion_test(bit)) + if (trace_recursion_test(bit)) { + do_ftrace_record_recursion(ip, pip); return -1; + } trace_recursion_set(bit); barrier(); return bit + 1; @@ -199,9 +219,10 @@ static __always_inline void trace_clear_recursion(int bit) * Returns: -1 if a recursion happened. * >= 0 if no recursion */ -static __always_inline int ftrace_test_recursion_trylock(void) +static __always_inline int ftrace_test_recursion_trylock(unsigned long ip, + unsigned long parent_ip) { - return trace_test_and_set_recursion(TRACE_FTRACE_START, TRACE_FTRACE_MAX); + return trace_test_and_set_recursion(ip, parent_ip, TRACE_FTRACE_START, TRACE_FTRACE_MAX); } /** |