From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>
Add an API traceeval_iterator_remove() that is safe to call in the
traceeval_iterator_next() loop. Currently, traceeval_remove() can also be
called "safely", but that may change in the future.
The main difference between traceeval_remove() and traceeval_iterator_remove()
is that that traceeval_iterator_remove() will NULL out the entry in the
sort array, and use this in the other iterator functions. If the entry is
NULL, it will not be returned.
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
include/traceeval-hist.h | 1 +
src/histograms.c | 48 ++++++++++++++++++++++++++++++++++++----
2 files changed, 45 insertions(+), 4 deletions(-)
diff --git a/include/traceeval-hist.h b/include/traceeval-hist.h
index d511c9c5f14c..7d67673ce7e5 100644
--- a/include/traceeval-hist.h
+++ b/include/traceeval-hist.h
@@ -190,5 +190,6 @@ int traceeval_iterator_query(struct traceeval_iterator *iter,
const union traceeval_data **results);
struct traceeval_stat *traceeval_iterator_stat(struct traceeval_iterator *iter,
struct traceeval_type *type);
+int traceeval_iterator_remove(struct traceeval_iterator *iter);
#endif /* __LIBTRACEEVAL_HIST_H__ */
diff --git a/src/histograms.c b/src/histograms.c
index fddd0f3587e2..0fbd9e0a353e 100644
--- a/src/histograms.c
+++ b/src/histograms.c
@@ -1305,10 +1305,13 @@ int traceeval_iterator_next(struct traceeval_iterator *iter,
iter->next = 0;
}
- if (iter->next >= iter->nr_entries)
- return 0;
+ do {
+ if (iter->next >= iter->nr_entries)
+ return 0;
+
+ entry = iter->entries[iter->next++];
+ } while (!entry);
- entry = iter->entries[iter->next++];
*keys = entry->keys;
return 1;
}
@@ -1338,6 +1341,9 @@ int traceeval_iterator_query(struct traceeval_iterator *iter,
return 0;
entry = iter->entries[iter->next - 1];
+ if (!entry)
+ return 0;
+
*results = entry->vals;
return 1;
@@ -1363,5 +1369,39 @@ struct traceeval_stat *traceeval_iterator_stat(struct traceeval_iterator *iter,
return NULL;
entry = iter->entries[iter->next - 1];
- return &entry->val_stats[type->index];
+ return entry ? &entry->val_stats[type->index] : NULL;
+}
+
+/**
+ * traceeval_iterator_remove - remove the current iterator entry
+ * @iter: The iterator to remove the entry from
+ *
+ * This will remove the current entry from the histogram.
+ * This is useful if the current entry should be removed. It will not
+ * affect the traceeval_iterator_next().
+ *
+ * Returns 1 if it successfully removed the entry, 0 if for some reason
+ * there was no "current entry" (called before traceeval_iterator_next()).
+ * or -1 on error.
+ */
+int traceeval_iterator_remove(struct traceeval_iterator *iter)
+{
+ struct traceeval *teval = iter->teval;
+ struct hash_table *hist = teval->hist;
+ struct entry *entry;
+
+ if (iter->next < 1 || iter->next > iter->nr_entries)
+ return 0;
+
+ entry = iter->entries[iter->next - 1];
+ if (!entry)
+ return 0;
+
+ hash_remove(hist, &entry->hash);
+
+ /* The entry no longer exists */
+ iter->entries[iter->next - 1] = NULL;
+ teval->update_counter++;
+
+ return 1;
}
--
2.40.1
|