On 08/07/2015 15:26, Kevin Wolf wrote:
>> +/* Suggested initial value is 100 */
>> +#define FLOOD_COUNTER(counter_name, initial) \
>> + static int counter_name = (initial)
No "static" here.
>> +#define NO_FLOOD(counter_name, code, suppress_message) \
>> + do { \
>> + int t_##counter_name = atomic_fetch_add(&counter_name, 0); \
>> + if (t_##counter_name > 0) { \
>> + code; \
>> + if (t_##counter_name == 1) { \
>> + suppress_message; \
>> + } \
>> + atomic_dec(&counter_name); \
>> + } \
>> +} while (0)
What you want is a cmpxchg loop like:
int old;
do
old = atomic_read(&counter_name);
while (old > 0 && atomic_cmpxchg(&counter_name, old, old - 1) != old);
if (old > 0) {
code;
if (old == 1) {
suppress_message;
}
}
but I would wrap it with a simple API like
void error_report_limited(int *counter, const char *s, ...);
void error_report_err_limited(int *counter, Error *err);
instead of your complex NO_FLOOD macro.
Paolo
