GCC Code Coverage Report

Directory: cvmfs/
File: cvmfs/fuse_evict.cc
Date: 2026-05-10 02:36:07
Exec Total Coverage
Lines: 112 164 68.3%
Branches: 62 127 48.8%
Line Branch Exec Source
1 /**
2 * This file is part of the CernVM File System.
3 */
4
5 #include "fuse_evict.h"
6
7 #include <inttypes.h>
8 #include <stdint.h>
9
10 #include <cassert>
11 #include <cstdlib>
12 #include <cstring>
13 #include <new>
14 #include <vector>
15
16 #include "glue_buffer.h"
17 #include "mountpoint.h"
18 #include "shortstring.h"
19 #include "util/logging.h"
20 #include "util/posix.h"
21 #include "util/smalloc.h"
22
23 using namespace std; // NOLINT
24
25 172 FuseInvalidator::Handle::Handle(unsigned timeout_s)
26
2/2
✓ Branch 1 taken 86 times.
✓ Branch 2 taken 86 times.
 172 : timeout_s_((timeout_s == 0) ? 0 : (timeout_s + kTimeoutSafetyMarginSec)) {
27 172 status_ = reinterpret_cast<atomic_int32 *>(smalloc(sizeof(atomic_int32)));
28 172 atomic_init32(status_);
29 172 }
30
31
32 172 FuseInvalidator::Handle::~Handle() { free(status_); }
33
34
35 215 void FuseInvalidator::Handle::WaitFor() {
36
2/2
✓ Branch 1 taken 258 times.
✓ Branch 2 taken 215 times.
 473 while (!IsDone())
37 258 SafeSleepMs(FuseInvalidator::kCheckTimeoutFreqMs);
38 215 }
39
40
41 //------------------------------------------------------------------------------
42
43
44 const unsigned FuseInvalidator::kTimeoutSafetyMarginSec = 1;
45 const unsigned FuseInvalidator::kCheckTimeoutFreqMs = 100;
46 const unsigned FuseInvalidator::kCheckTimeoutFreqOps = 256;
47
48 bool FuseInvalidator::g_fuse_notify_invalidation_ = true;
49
50 129 bool FuseInvalidator::HasFuseNotifyInval() {
51 /**
52 * Technically, also libfuse 2.8 has support. Libfuse 2.8 comes with EL6,
53 * which had bugs reported related to the fuse_notify_inval_...() functions.
54 * Since just waiting for the timeout works perfectly fine, there is no reason
55 * to optimize for forced cache eviction too aggressively.
56 *
57 * TODO(jblomer): could we have libfuse 2.9 or higher with a very old kernel
58 * that doesn't support active invalidation? How old does the kernel need
59 * to be? Probably that situation is never triggered in practice.
60 */
61 129 return FuseInvalidator::g_fuse_notify_invalidation_ && (FUSE_VERSION >= 29);
62 }
63
64
65 ✗ FuseInvalidator::FuseInvalidator(MountPoint *mount_point,
66 void **fuse_channel_or_session,
67 ✗ bool fuse_notify_invalidation)
68 ✗ : mount_point_(mount_point)
69 ✗ , inode_tracker_(mount_point->inode_tracker())
70 ✗ , dentry_tracker_(mount_point->dentry_tracker())
71 ✗ , fuse_channel_or_session_(fuse_channel_or_session)
72 ✗ , spawned_(false) {
73 ✗ g_fuse_notify_invalidation_ = fuse_notify_invalidation;
74 ✗ memset(&thread_invalidator_, 0, sizeof(thread_invalidator_));
75 ✗ atomic_init32(&terminated_);
76 }
77
78 215 FuseInvalidator::FuseInvalidator(glue::InodeTracker *inode_tracker,
79 glue::DentryTracker *dentry_tracker,
80 void **fuse_channel_or_session,
81 215 bool fuse_notify_invalidation)
82 215 : mount_point_(NULL)
83 215 , inode_tracker_(inode_tracker)
84 215 , dentry_tracker_(dentry_tracker)
85 215 , fuse_channel_or_session_(fuse_channel_or_session)
86
1/2
✓ Branch 3 taken 215 times.
✗ Branch 4 not taken.
 215 , spawned_(false) {
87 215 g_fuse_notify_invalidation_ = fuse_notify_invalidation;
88 215 memset(&thread_invalidator_, 0, sizeof(thread_invalidator_));
89 215 atomic_init32(&terminated_);
90 215 }
91
92
93 215 FuseInvalidator::~FuseInvalidator() {
94 215 atomic_cas32(&terminated_, 0, 1);
95
2/2
✓ Branch 0 taken 172 times.
✓ Branch 1 taken 43 times.
 215 if (spawned_) {
96 172 QuitCommand *cmd = new (smalloc(sizeof(QuitCommand))) QuitCommand();
97 172 channel_.PushBack(cmd);
98 172 pthread_join(thread_invalidator_, NULL);
99 }
100 215 }
101
102
103 215 void FuseInvalidator::InvalidateInodes(Handle *handle) {
104
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 215 times.
 215 assert(handle != NULL);
105 InvalInodesCommand *inval_inodes_command = new (
106 215 smalloc(sizeof(InvalInodesCommand))) InvalInodesCommand();
107 215 inval_inodes_command->handle = handle;
108 215 channel_.PushBack(inval_inodes_command);
109 215 }
110
111 ✗ void FuseInvalidator::InvalidateDentry(uint64_t parent_ino,
112 const NameString &name) {
113 InvalDentryCommand *inval_dentry_command;
114 ✗ vector<Command *> *items = channel_.StartEnqueueing();
115 ✗ for (size_t i = 0; i < items->size(); ++i) {
116 ✗ inval_dentry_command = dynamic_cast<InvalDentryCommand *>(items->at(i));
117 ✗ if (!inval_dentry_command)
118 ✗ continue;
119 ✗ if (inval_dentry_command->parent_ino != parent_ino)
120 ✗ continue;
121 ✗ if (inval_dentry_command->name != name)
122 ✗ continue;
123 ✗ channel_.AbortEnqueueing();
124 ✗ return;
125 }
126
127 ✗ inval_dentry_command = new (smalloc(sizeof(InvalDentryCommand)))
128 ✗ InvalDentryCommand();
129 ✗ inval_dentry_command->parent_ino = parent_ino;
130 ✗ inval_dentry_command->name = name;
131 ✗ items->push_back(inval_dentry_command);
132 ✗ channel_.CommitEnqueueing();
133 }
134
135 172 void *FuseInvalidator::MainInvalidator(void *data) {
136 172 FuseInvalidator *invalidator = reinterpret_cast<FuseInvalidator *>(data);
137 172 LogCvmfs(kLogCvmfs, kLogDebug, "starting dentry invalidator thread");
138
139 172 bool reported_missing_inval_support = false;
140 while (true) {
141
1/2
✓ Branch 1 taken 387 times.
✗ Branch 2 not taken.
 387 Command *command = invalidator->channel_.PopFront();
142
143
3/4
✓ Branch 0 taken 387 times.
✗ Branch 1 not taken.
✓ Branch 2 taken 172 times.
✓ Branch 3 taken 215 times.
 387 if (dynamic_cast<QuitCommand *>(command)) {
144 172 command->~Command();
145 172 free(command);
146 172 break;
147 }
148
149 InvalDentryCommand
150
1/2
✓ Branch 0 taken 215 times.
✗ Branch 1 not taken.
 215 *inval_dentry_command = dynamic_cast<InvalDentryCommand *>(command);
151
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 215 times.
 215 if (inval_dentry_command) {
152 ✗ if (invalidator->fuse_channel_or_session_ == NULL) {
153 ✗ if (!reported_missing_inval_support) {
154 ✗ LogCvmfs(kLogCvmfs, kLogSyslogWarn,
155 "missing fuse support for dentry invalidation "
156 "(%" PRIu64 "/%s)",
157 inval_dentry_command->parent_ino,
158 ✗ inval_dentry_command->name.ToString().c_str());
159 ✗ reported_missing_inval_support = true;
160 }
161 ✗ inval_dentry_command->~InvalDentryCommand();
162 ✗ free(inval_dentry_command);
163 86 continue;
164 }
165 ✗ LogCvmfs(kLogCvmfs, kLogDebug, "evicting single dentry %" PRIu64 "/%s",
166 inval_dentry_command->parent_ino,
167 ✗ inval_dentry_command->name.ToString().c_str());
168 #if CVMFS_USE_LIBFUSE == 2
169 ✗ fuse_lowlevel_notify_inval_entry(
170 *reinterpret_cast<struct fuse_chan **>(
171 ✗ invalidator->fuse_channel_or_session_),
172 inval_dentry_command->parent_ino,
173 inval_dentry_command->name.GetChars(),
174 ✗ inval_dentry_command->name.GetLength());
175 #else
176 ✗ fuse_lowlevel_notify_inval_entry(
177 *reinterpret_cast<struct fuse_session **>(
178 ✗ invalidator->fuse_channel_or_session_),
179 inval_dentry_command->parent_ino,
180 inval_dentry_command->name.GetChars(),
181 ✗ inval_dentry_command->name.GetLength());
182 #endif
183 ✗ inval_dentry_command->~InvalDentryCommand();
184 ✗ free(inval_dentry_command);
185 ✗ continue;
186 }
187
188 InvalInodesCommand
189
1/2
✓ Branch 0 taken 215 times.
✗ Branch 1 not taken.
 215 *inval_inodes_command = dynamic_cast<InvalInodesCommand *>(command);
190
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 215 times.
 215 assert(inval_inodes_command);
191
192 215 Handle *handle = inval_inodes_command->handle;
193
1/2
✓ Branch 1 taken 215 times.
✗ Branch 2 not taken.
 215 LogCvmfs(kLogCvmfs, kLogDebug, "invalidating kernel caches, timeout %u",
194 handle->timeout_s_);
195 215 inval_inodes_command->~InvalInodesCommand();
196 215 free(inval_inodes_command);
197
198 215 const uint64_t deadline = platform_monotonic_time() + handle->timeout_s_;
199
200 // Fallback: drainout by timeout
201 516 if ((invalidator->fuse_channel_or_session_ == NULL)
202
5/6
✓ Branch 0 taken 129 times.
✓ Branch 1 taken 86 times.
✗ Branch 3 not taken.
✓ Branch 4 taken 129 times.
✓ Branch 5 taken 86 times.
✓ Branch 6 taken 129 times.
 215 || !HasFuseNotifyInval()) {
203
2/2
✓ Branch 1 taken 43 times.
✓ Branch 2 taken 43 times.
 86 while (platform_monotonic_time() < deadline) {
204
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 SafeSleepMs(kCheckTimeoutFreqMs);
205
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 if (atomic_read32(&invalidator->terminated_) == 1) {
206
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 LogCvmfs(kLogCvmfs, kLogDebug,
207 "cancel cache eviction due to termination");
208 43 break;
209 }
210 }
211 86 handle->SetDone();
212 86 continue;
213 }
214
215 // We must not hold a lock when calling fuse_lowlevel_notify_inval_entry.
216 // Therefore, we first copy all the inodes into a temporary data structure.
217 glue::InodeTracker::Cursor inode_cursor(
218
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 invalidator->inode_tracker_->BeginEnumerate());
219 uint64_t inode;
220
3/4
✓ Branch 1 taken 132225 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 132096 times.
✓ Branch 4 taken 129 times.
 132225 while (invalidator->inode_tracker_->NextInode(&inode_cursor, &inode)) {
221
1/2
✓ Branch 1 taken 132096 times.
✗ Branch 2 not taken.
 132096 invalidator->evict_list_.PushBack(inode);
222 }
223
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 invalidator->inode_tracker_->EndEnumerate(&inode_cursor);
224
225 129 unsigned i = 0;
226 129 const unsigned N = invalidator->evict_list_.size();
227
2/2
✓ Branch 0 taken 66048 times.
✓ Branch 1 taken 43 times.
 66091 while (i < N) {
228 66048 uint64_t inode = invalidator->evict_list_.At(i);
229
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 66048 times.
 66048 if (inode == 0)
230 ✗ inode = FUSE_ROOT_ID;
231 // Can fail, e.g. the inode might be already evicted
232
233 int dbg_retval;
234
235 #if CVMFS_USE_LIBFUSE == 2
236 66048 dbg_retval = fuse_lowlevel_notify_inval_inode(
237 *reinterpret_cast<struct fuse_chan **>(
238 66048 invalidator->fuse_channel_or_session_),
239 inode, 0, 0);
240 #else
241 ✗ dbg_retval = fuse_lowlevel_notify_inval_inode(
242 *reinterpret_cast<struct fuse_session **>(
243 ✗ invalidator->fuse_channel_or_session_),
244 inode, 0, 0);
245 #endif
246
1/2
✓ Branch 1 taken 66048 times.
✗ Branch 2 not taken.
 66048 LogCvmfs(kLogCvmfs, kLogDebug,
247 "evicting inode %" PRIu64 " with retval: %d", inode, dbg_retval);
248
249 (void)dbg_retval; // prevent compiler complaining
250
251
2/2
✓ Branch 0 taken 258 times.
✓ Branch 1 taken 65790 times.
 66048 if ((++i % kCheckTimeoutFreqOps) == 0) {
252
2/2
✓ Branch 1 taken 43 times.
✓ Branch 2 taken 215 times.
 258 if (platform_monotonic_time() >= deadline) {
253
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 LogCvmfs(kLogCvmfs, kLogDebug,
254 "cancel cache eviction after %u entries due to timeout", i);
255 43 break;
256 }
257
2/2
✓ Branch 1 taken 43 times.
✓ Branch 2 taken 172 times.
 215 if (atomic_read32(&invalidator->terminated_) == 1) {
258
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 LogCvmfs(kLogCvmfs, kLogDebug,
259 "cancel cache eviction due to termination");
260 43 break;
261 }
262 }
263 }
264
265 // Do the dentry tracker last to increase the effectiveness of pruning
266
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 invalidator->dentry_tracker_->Prune();
267 // Copy and empty the dentry tracker in a single atomic operation
268
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 glue::DentryTracker *dentries_copy = invalidator->dentry_tracker_->Move();
269
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 glue::DentryTracker::Cursor dentry_cursor = dentries_copy->BeginEnumerate();
270 uint64_t entry_parent;
271 129 NameString entry_name;
272 129 i = 0;
273
274 #if CVMFS_USE_LIBFUSE == 2
275 int (*notify_func)(struct fuse_chan *, fuse_ino_t, const char *, size_t);
276 129 notify_func = &fuse_lowlevel_notify_inval_entry;
277 #else
278 int (*notify_func)(struct fuse_session *, fuse_ino_t, const char *, size_t);
279 ✗ notify_func = &fuse_lowlevel_notify_inval_entry;
280 #if FUSE_VERSION >= FUSE_MAKE_VERSION(3, 16)
281 // must be libfuse >= 3.16, otherwise the signature is wrong and it
282 // will fail building
283 // mount_point can only be NULL for unittests
284 if (invalidator->mount_point_ != NULL
285 && invalidator->mount_point_->fuse_expire_entry()) {
286 notify_func = &fuse_lowlevel_notify_expire_entry;
287 }
288 #endif
289 #endif
290
291 129 while (
292
3/4
✓ Branch 1 taken 55126 times.
✗ Branch 2 not taken.
✓ Branch 3 taken 55040 times.
✓ Branch 4 taken 86 times.
 55126 dentries_copy->NextEntry(&dentry_cursor, &entry_parent, &entry_name)) {
293
1/2
✓ Branch 2 taken 55040 times.
✗ Branch 3 not taken.
 55040 LogCvmfs(kLogCvmfs, kLogDebug, "evicting dentry %lu --> %s", entry_parent,
294 entry_name.c_str());
295 // Can fail, e.g. the entry might be already evicted
296 #if CVMFS_USE_LIBFUSE == 2
297 struct fuse_chan
298 55040 *channel_or_session = *reinterpret_cast<struct fuse_chan **>(
299 55040 invalidator->fuse_channel_or_session_);
300 #else
301 struct fuse_session
302 ✗ *channel_or_session = *reinterpret_cast<struct fuse_session **>(
303 ✗ invalidator->fuse_channel_or_session_);
304 #endif
305
306
1/2
✓ Branch 2 taken 55040 times.
✗ Branch 3 not taken.
 55040 notify_func(channel_or_session, entry_parent, entry_name.GetChars(),
307 55040 entry_name.GetLength());
308
309
2/2
✓ Branch 0 taken 215 times.
✓ Branch 1 taken 54825 times.
 55040 if ((++i % kCheckTimeoutFreqOps) == 0) {
310
2/2
✓ Branch 1 taken 43 times.
✓ Branch 2 taken 172 times.
 215 if (atomic_read32(&invalidator->terminated_) == 1) {
311
1/2
✓ Branch 1 taken 43 times.
✗ Branch 2 not taken.
 43 LogCvmfs(kLogCvmfs, kLogDebug,
312 "cancel cache eviction due to termination");
313 43 break;
314 }
315 }
316 }
317
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 dentries_copy->EndEnumerate(&dentry_cursor);
318
1/2
✓ Branch 0 taken 129 times.
✗ Branch 1 not taken.
 129 delete dentries_copy;
319
320 129 handle->SetDone();
321
1/2
✓ Branch 1 taken 129 times.
✗ Branch 2 not taken.
 129 invalidator->evict_list_.Clear();
322 344 }
323
324 172 LogCvmfs(kLogCvmfs, kLogDebug, "stopping dentry invalidator thread");
325 172 return NULL;
326 }
327
328
329 172 void FuseInvalidator::Spawn() {
330 int retval;
331 172 retval = pthread_create(&thread_invalidator_, NULL, MainInvalidator, this);
332
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 172 times.
 172 assert(retval == 0);
333 172 spawned_ = true;
334 172 }
335