Tue, 28 May 2013 09:32:06 +0200
8013895: G1: G1SummarizeRSetStats output on Linux needs improvemen
Summary: Fixed the output of G1SummarizeRSetStats: too small datatype for the number of concurrently processed cards, added concurrent remembered set thread time retrieval for Linux and Windows (BSD uses os::elapsedTime() now), and other cleanup. The information presented during VM operation is now relative to the previous output, not always cumulative if G1SummarizeRSetStatsPeriod > 0. At VM exit, the code prints a cumulative summary.
Reviewed-by: johnc, jwilhelm
1 /*
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25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
28 #include "gc_implementation/g1/heapRegion.hpp"
30 // Large buffer for some cases where the output might be larger than normal.
31 #define HRS_ERR_MSG_BUFSZ 512
32 typedef FormatBuffer<HRS_ERR_MSG_BUFSZ> hrs_err_msg;
34 // Set verification will be forced either if someone defines
35 // HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
36 // asserts are compiled in.
37 #ifndef HEAP_REGION_SET_FORCE_VERIFY
38 #define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
39 #endif // HEAP_REGION_SET_FORCE_VERIFY
41 //////////////////// HeapRegionSetBase ////////////////////
43 // Base class for all the classes that represent heap region sets. It
44 // contains the basic attributes that each set needs to maintain
45 // (e.g., length, region num, used bytes sum) plus any shared
46 // functionality (e.g., verification).
48 class hrs_ext_msg;
50 typedef enum {
51 HRSPhaseNone,
52 HRSPhaseEvacuation,
53 HRSPhaseCleanup,
54 HRSPhaseFullGC
55 } HRSPhase;
57 class HRSPhaseSetter;
59 class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
60 friend class hrs_ext_msg;
61 friend class HRSPhaseSetter;
62 friend class VMStructs;
64 protected:
65 static uint _unrealistically_long_length;
67 // The number of regions added to the set. If the set contains
68 // only humongous regions, this reflects only 'starts humongous'
69 // regions and does not include 'continues humongous' ones.
70 uint _length;
72 // The total number of regions represented by the set. If the set
73 // does not contain humongous regions, this should be the same as
74 // _length. If the set contains only humongous regions, this will
75 // include the 'continues humongous' regions.
76 uint _region_num;
78 // We don't keep track of the total capacity explicitly, we instead
79 // recalculate it based on _region_num and the heap region size.
81 // The sum of used bytes in the all the regions in the set.
82 size_t _total_used_bytes;
84 const char* _name;
86 bool _verify_in_progress;
87 uint _calc_length;
88 uint _calc_region_num;
89 size_t _calc_total_capacity_bytes;
90 size_t _calc_total_used_bytes;
92 // This is here so that it can be used in the subclasses to assert
93 // something different depending on which phase the GC is in. This
94 // can be particularly helpful in the check_mt_safety() methods.
95 static HRSPhase _phase;
97 // Only used by HRSPhaseSetter.
98 static void clear_phase();
99 static void set_phase(HRSPhase phase);
101 // verify_region() is used to ensure that the contents of a region
102 // added to / removed from a set are consistent. Different sets
103 // make different assumptions about the regions added to them. So
104 // each set can override verify_region_extra(), which is called
105 // from verify_region(), and do any extra verification it needs to
106 // perform in that.
107 virtual const char* verify_region_extra(HeapRegion* hr) { return NULL; }
108 bool verify_region(HeapRegion* hr,
109 HeapRegionSetBase* expected_containing_set);
111 // Indicates whether all regions in the set should be humongous or
112 // not. Only used during verification.
113 virtual bool regions_humongous() = 0;
115 // Indicates whether all regions in the set should be empty or
116 // not. Only used during verification.
117 virtual bool regions_empty() = 0;
119 // Subclasses can optionally override this to do MT safety protocol
120 // checks. It is called in an assert from all methods that perform
121 // updates on the set (and subclasses should also call it too).
122 virtual bool check_mt_safety() { return true; }
124 // fill_in_ext_msg() writes the the values of the set's attributes
125 // in the custom err_msg (hrs_ext_msg). fill_in_ext_msg_extra()
126 // allows subclasses to append further information.
127 virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg) { }
128 void fill_in_ext_msg(hrs_ext_msg* msg, const char* message);
130 // It updates the fields of the set to reflect hr being added to
131 // the set.
132 inline void update_for_addition(HeapRegion* hr);
134 // It updates the fields of the set to reflect hr being added to
135 // the set and tags the region appropriately.
136 inline void add_internal(HeapRegion* hr);
138 // It updates the fields of the set to reflect hr being removed
139 // from the set.
140 inline void update_for_removal(HeapRegion* hr);
142 // It updates the fields of the set to reflect hr being removed
143 // from the set and tags the region appropriately.
144 inline void remove_internal(HeapRegion* hr);
146 // It clears all the fields of the sets. Note: it will not iterate
147 // over the set and remove regions from it. It assumes that the
148 // caller has already done so. It will literally just clear the fields.
149 virtual void clear();
151 HeapRegionSetBase(const char* name);
153 public:
154 static void set_unrealistically_long_length(uint len);
156 const char* name() { return _name; }
158 uint length() { return _length; }
160 bool is_empty() { return _length == 0; }
162 uint region_num() { return _region_num; }
164 size_t total_capacity_bytes() {
165 return (size_t) region_num() << HeapRegion::LogOfHRGrainBytes;
166 }
168 size_t total_used_bytes() { return _total_used_bytes; }
170 virtual void verify();
171 void verify_start();
172 void verify_next_region(HeapRegion* hr);
173 void verify_end();
175 #if HEAP_REGION_SET_FORCE_VERIFY
176 void verify_optional() {
177 verify();
178 }
179 #else // HEAP_REGION_SET_FORCE_VERIFY
180 void verify_optional() { }
181 #endif // HEAP_REGION_SET_FORCE_VERIFY
183 virtual void print_on(outputStream* out, bool print_contents = false);
184 };
186 // Customized err_msg for heap region sets. Apart from a
187 // assert/guarantee-specific message it also prints out the values of
188 // the fields of the associated set. This can be very helpful in
189 // diagnosing failures.
191 class hrs_ext_msg : public hrs_err_msg {
192 public:
193 hrs_ext_msg(HeapRegionSetBase* set, const char* message) : hrs_err_msg("") {
194 set->fill_in_ext_msg(this, message);
195 }
196 };
198 class HRSPhaseSetter {
199 public:
200 HRSPhaseSetter(HRSPhase phase) {
201 HeapRegionSetBase::set_phase(phase);
202 }
203 ~HRSPhaseSetter() {
204 HeapRegionSetBase::clear_phase();
205 }
206 };
208 // These two macros are provided for convenience, to keep the uses of
209 // these two asserts a bit more concise.
211 #define hrs_assert_mt_safety_ok(_set_) \
212 do { \
213 assert((_set_)->check_mt_safety(), hrs_ext_msg((_set_), "MT safety")); \
214 } while (0)
216 #define hrs_assert_region_ok(_set_, _hr_, _expected_) \
217 do { \
218 assert((_set_)->verify_region((_hr_), (_expected_)), \
219 hrs_ext_msg((_set_), "region verification")); \
220 } while (0)
222 //////////////////// HeapRegionSet ////////////////////
224 #define hrs_assert_sets_match(_set1_, _set2_) \
225 do { \
226 assert(((_set1_)->regions_humongous() == \
227 (_set2_)->regions_humongous()) && \
228 ((_set1_)->regions_empty() == (_set2_)->regions_empty()), \
229 hrs_err_msg("the contents of set %s and set %s should match", \
230 (_set1_)->name(), (_set2_)->name())); \
231 } while (0)
233 // This class represents heap region sets whose members are not
234 // explicitly tracked. It's helpful to group regions using such sets
235 // so that we can reason about all the region groups in the heap using
236 // the same interface (namely, the HeapRegionSetBase API).
238 class HeapRegionSet : public HeapRegionSetBase {
239 protected:
240 virtual const char* verify_region_extra(HeapRegion* hr) {
241 if (hr->next() != NULL) {
242 return "next() should always be NULL as we do not link the regions";
243 }
245 return HeapRegionSetBase::verify_region_extra(hr);
246 }
248 HeapRegionSet(const char* name) : HeapRegionSetBase(name) {
249 clear();
250 }
252 public:
253 // It adds hr to the set. The region should not be a member of
254 // another set.
255 inline void add(HeapRegion* hr);
257 // It removes hr from the set. The region should be a member of
258 // this set.
259 inline void remove(HeapRegion* hr);
261 // It removes a region from the set. Instead of updating the fields
262 // of the set to reflect this removal, it accumulates the updates
263 // in proxy_set. The idea is that proxy_set is thread-local to
264 // avoid multiple threads updating the fields of the set
265 // concurrently and having to synchronize. The method
266 // update_from_proxy() will update the fields of the set from the
267 // proxy_set.
268 inline void remove_with_proxy(HeapRegion* hr, HeapRegionSet* proxy_set);
270 // After multiple calls to remove_with_proxy() the updates to the
271 // fields of the set are accumulated in proxy_set. This call
272 // updates the fields of the set from proxy_set.
273 void update_from_proxy(HeapRegionSet* proxy_set);
274 };
276 //////////////////// HeapRegionLinkedList ////////////////////
278 // A set that links all the regions added to it in a singly-linked
279 // list. We should try to avoid doing operations that iterate over
280 // such lists in performance critical paths. Typically we should
281 // add / remove one region at a time or concatenate two lists. All
282 // those operations are done in constant time.
284 class HeapRegionLinkedListIterator;
286 class HeapRegionLinkedList : public HeapRegionSetBase {
287 friend class HeapRegionLinkedListIterator;
289 private:
290 HeapRegion* _head;
291 HeapRegion* _tail;
293 // These are provided for use by the friend classes.
294 HeapRegion* head() { return _head; }
295 HeapRegion* tail() { return _tail; }
297 protected:
298 virtual void fill_in_ext_msg_extra(hrs_ext_msg* msg);
300 // See the comment for HeapRegionSetBase::clear()
301 virtual void clear();
303 HeapRegionLinkedList(const char* name) : HeapRegionSetBase(name) {
304 clear();
305 }
307 public:
308 // It adds hr to the list as the new head. The region should not be
309 // a member of another set.
310 inline void add_as_head(HeapRegion* hr);
312 // It adds hr to the list as the new tail. The region should not be
313 // a member of another set.
314 inline void add_as_tail(HeapRegion* hr);
316 // It removes and returns the head of the list. It assumes that the
317 // list is not empty so it will return a non-NULL value.
318 inline HeapRegion* remove_head();
320 // Convenience method.
321 inline HeapRegion* remove_head_or_null();
323 // It moves the regions from from_list to this list and empties
324 // from_list. The new regions will appear in the same order as they
325 // were in from_list and be linked in the beginning of this list.
326 void add_as_head(HeapRegionLinkedList* from_list);
328 // It moves the regions from from_list to this list and empties
329 // from_list. The new regions will appear in the same order as they
330 // were in from_list and be linked in the end of this list.
331 void add_as_tail(HeapRegionLinkedList* from_list);
333 // It empties the list by removing all regions from it.
334 void remove_all();
336 // It removes all regions in the list that are pending for removal
337 // (i.e., they have been tagged with "pending_removal"). The list
338 // must not be empty, target_count should reflect the exact number
339 // of regions that are pending for removal in the list, and
340 // target_count should be > 1 (currently, we never need to remove a
341 // single region using this).
342 void remove_all_pending(uint target_count);
344 virtual void verify();
346 virtual void print_on(outputStream* out, bool print_contents = false);
347 };
349 //////////////////// HeapRegionLinkedListIterator ////////////////////
351 // Iterator class that provides a convenient way to iterate over the
352 // regions of a HeapRegionLinkedList instance.
354 class HeapRegionLinkedListIterator : public StackObj {
355 private:
356 HeapRegionLinkedList* _list;
357 HeapRegion* _curr;
359 public:
360 bool more_available() {
361 return _curr != NULL;
362 }
364 HeapRegion* get_next() {
365 assert(more_available(),
366 "get_next() should be called when more regions are available");
368 // If we are going to introduce a count in the iterator we should
369 // do the "cycle" check.
371 HeapRegion* hr = _curr;
372 assert(_list->verify_region(hr, _list), "region verification");
373 _curr = hr->next();
374 return hr;
375 }
377 HeapRegionLinkedListIterator(HeapRegionLinkedList* list)
378 : _curr(NULL), _list(list) {
379 _curr = list->head();
380 }
381 };
383 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP