s390/cpumf: remove 60 seconds read limit

Remove the 60 seconds read interval limit. Do not impose any limit
at all and allow read of complete counter sets.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

diff --git a/arch/s390/kernel/perf_cpum_cf_diag.c b/arch/s390/kernel/perf_cpum_cf_diag.c
index db4877bbb9aa5626702bf6068de92accdaa9e81a..5eebc912df5a98cc059ba7e68dd5d182f906dffd 100644 (file)
--- a/arch/s390/kernel/perf_cpum_cf_diag.c
+++ b/arch/s390/kernel/perf_cpum_cf_diag.c
@@ -29,9 +29,7 @@
 #include <asm/perf_cpum_cf_diag.h>
 
 #define        CF_DIAG_CTRSET_DEF              0xfeef  /* Counter set header mark */
-#define CF_DIAG_MIN_INTERVAL           60      /* Minimum counter set read */
                                                /* interval in seconds */
-static unsigned long cf_diag_interval = CF_DIAG_MIN_INTERVAL;
 static unsigned int cf_diag_cpu_speed;
 static debug_info_t *cf_diag_dbg;
 
@@ -729,7 +727,6 @@ static DEFINE_MUTEX(cf_diag_ctrset_mutex);
 static struct cf_diag_ctrset {
        unsigned long ctrset;           /* Bit mask of counter set to read */
        cpumask_t mask;                 /* CPU mask to read from */
-       time64_t lastread;              /* Epoch counter set last read */
 } cf_diag_ctrset;
 
 static void cf_diag_ctrset_clear(void)
@@ -866,27 +863,16 @@ static int cf_diag_all_read(unsigned long arg)
 {
        struct cf_diag_call_on_cpu_parm p;
        cpumask_var_t mask;
-       time64_t now;
-       int rc = 0;
+       int rc;
 
        debug_sprintf_event(cf_diag_dbg, 5, "%s\n", __func__);
        if (!alloc_cpumask_var(&mask, GFP_KERNEL))
                return -ENOMEM;
-       now = ktime_get_seconds();
-       if (cf_diag_ctrset.lastread + cf_diag_interval > now) {
-               debug_sprintf_event(cf_diag_dbg, 5, "%s now %lld "
-                                   " lastread %lld\n", __func__, now,
-                                   cf_diag_ctrset.lastread);
-               rc = -EAGAIN;
-               goto out;
-       } else {
-               cf_diag_ctrset.lastread = now;
-       }
+
        p.sets = cf_diag_ctrset.ctrset;
        cpumask_and(mask, &cf_diag_ctrset.mask, cpu_online_mask);
        on_each_cpu_mask(mask, cf_diag_cpu_read, &p, 1);
        rc = cf_diag_all_copy(arg, mask);
-out:
        free_cpumask_var(mask);
        debug_sprintf_event(cf_diag_dbg, 5, "%s rc %d\n", __func__, rc);
        return rc;