3 #define _MARK_TRAP (1 << MARK_TRAP)
7 #define _MARK_PREEMPT (1 << MARK_PREEMPT)
8 Permits blocking calls within probe.
9 How to deal with probe removal :
10 Each site has its per cpu probe_exec counters. The sum of the signed values
11 gives the number of executors. Operations inc/dec on those values are done
12 within preempt disable so they can be done non atomically without risking
13 to be corrupted by another CPU.
14 1 - disable site and remove call
15 2 - while sum of probe_exec counters != 0, sleep 50ms
17 - if someone sleeps in here for a long time or waits for
18 a busy ressource, removal may fail with -EBUSY.
24 probe_exec[smp_processor_id()]++;
28 probe_exec[smp_processor_id()]--;
32 #define MARK_RESCHED 3
33 #define _MARK_RESCHED (1 << MARK_RESCHED)
34 preempt_schedule() will be called by the marker.
37 #define _MARK_PRINTK (1 << MARK_PRINTK)
38 vprintk can be called in the probe/printk can be called as probe.
40 #define MARK_LOCK_SAFE
41 #define _MARK_LOCK_SAFE (1 << MARK_LOCK_SAFE)
42 It is completely safe to take a lock, disable irqs, softirqs, ... from this marker.
43 If unset, checking the context must be done to insure no deadlock or recursive
46 #define _MARK_DEFAULT (_MARK_TRAP | _MARK_RESCHED | _MARK_PRINTK)
48 #define MARK (format, args...) _MARK(MARK_DEFAULT, format, ## args)
51 #define _MARK(opt, format, args...) \
53 if (opt & _MARK_TRAP) \
54 MARK(opt, format, ## args); \
56 GEN_MARK(opt, format, ## args); \
60 #define _MARK(opt, format, args...) MARK(opt, format, ## args);
63 MARK(opt, format, ...) \
64 static declare opt in struct; \
67 if (opt & _MARK_PREEMPT) {
68 probe_exec[smp_processor_id()]++;
69 if (opt & _MARK_RESCHED)
72 preempt_enable_no_resched();
75 if (opt & _MARK_PREEMPT) {
77 probe_exec[smp_processor_id()]--;
79 if (opt & _MARK_RESCHED)
82 preempt_enable_no_resched();