le_mem.h

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1 /**
2  * @page c_memory Dynamic Memory Allocation API
3  *
4  *
5  * @subpage le_mem.h "API Reference"
6  *
7  * <HR>
8  *
9  * Dynamic memory allocation (especially deallocation) using the C runtime heap, through
10  * malloc, free, strdup, calloc, realloc, etc. can result in performance degradation and out-of-memory
11  * conditions.
12  *
13  * This is due to fragmentation of the heap. The degraded performance and exhausted memory result from indirect interactions
14  * within the heap between unrelated application code. These issues are non-deterministic,
15  * and can be very difficult to rectify.
16  *
17  * Memory Pools offer a powerful solution. They trade-off a deterministic amount of
18  * memory for
19  * - deterministic behaviour,
20  * - O(1) allocation and release performance, and
21  * - built-in memory allocation tracking.
22  *
23  * And it brings the power of @b destructors to C!
24  *
25  * @todo
26  * Do we need to add a "resettable heap" option to the memory management tool kit?
27  *
28  *
29  * @section mem_overview Overview
30  *
31  * The most basic usage involves:
32  * - Creating a pool (usually done once at process start-up)
33  * - Allocating objects (memory blocks) from a pool
34  * - Releasing objects back to their pool.
35  *
36  * Pools generally can't be deleted. You create them when your process
37  * starts-up, and use them until your process terminates. It's up to the OS to clean-up the memory
38  * pools, along with everything else your process is using, when your process terminates. (Although,
39  * if you find yourself really needing to delete pools, @ref mem_sub_pools could offer you a solution.)
40  *
41  * Pools also support the following advanced features:
42  * - reference counting
43  * - destructors
44  * - statistics
45  * - multi-threading
46  * - sub-pools (pools that can be deleted).
47  *
48  * The following sections describe these, beginning with the most basic usage and working up to more
49  * advanced topics.
50  *
51  *
52  * @section mem_creating Creating a Pool
53  *
54  * Before allocating memory from a pool, the pool must be created using le_mem_CreatePool(), passing
55  * it the name of the pool and the size of the objects to be allocated from that pool. This returns
56  * a reference to the new pool, which has zero free objects in it.
57  *
58  * To populate your new pool with free objects, you call @c le_mem_ExpandPool().
59  * This is separated into two functions (rather than having
60  * one function with three parameters) to make it virtually impossible to accidentally get the parameters
61  * in the wrong order (which would result in nasty bugs that couldn't be caught by the compiler).
62  * The ability to expand pools comes in handy (see @ref mem_pool_sizes).
63  *
64  * This code sample defines a class "Point" and a pool "PointPool" used to
65  * allocate memory for objects of that class:
66  * @code
67  * #define MAX_POINTS 12 // Maximum number of points that can be handled.
68  *
69  * typedef struct
70  * {
71  * int x; // pixel position along x-axis
72  * int y; // pixel position along y-axis
73  * }
74  * Point_t;
75  *
76  * le_mem_PoolRef_t PointPool;
77  *
78  * int xx_pt_ProcessStart(void)
79  * {
80  * PointPool = le_mem_CreatePool("xx.pt.Points", sizeof(Point_t));
81  * le_mem_ExpandPool(PointPool, MAX_POINTS);
82  *
83  * return SUCCESS;
84  * }
85  * @endcode
86  *
87  * To make things easier for power-users, @c le_mem_ExpandPool() returns the same pool
88  * reference that it was given. This allows the xx_pt_ProcessStart() function to be re-implemented
89  * as follows:
90  * @code
91  * int xx_pt_ProcessStart(void)
92  * {
93  * PointPool = le_mem_ExpandPool(le_mem_CreatePool(sizeof(Point_t)), MAX_POINTS);
94  *
95  * return SUCCESS;
96  * }
97  * @endcode
98  *
99  * Although this requires a dozen or so fewer keystrokes of typing and occupies one less line
100  * of code, it's arguably less readable than the previous example.
101  *
102  * For a discussion on how to pick the number of objects to have in your pools, see @ref mem_pool_sizes.
103  *
104  * @section mem_allocating Allocating From a Pool
105  *
106  * Allocating from a pool has multiple options:
107  * - @c le_mem_TryAlloc() - Quietly return NULL if there are no free blocks in the pool.
108  * - @c le_mem_AssertAlloc() - Log an error and take down the process if there are no free blocks in
109  * the pool.
110  * - @c le_mem_ForceAlloc() - If there are no free blocks in the pool, log a warning and automatically
111  * expand the pool (or log an error and terminate the calling process there's
112  * not enough free memory to expand the pool).
113  *
114  * All of these functions take a pool reference and return a pointer to the object
115  * allocated from the pool.
116  *
117  * The first option, using @c le_mem_TryAlloc(), is the
118  * closest to the way good old malloc() works. It requires the caller check the
119  * return code to see if it's NULL. This can be annoying enough that a lot of
120  * people get lazy and don't check the return code (Bad programmer! Bad!). It turns out that
121  * this option isn't really what people usually want (but occasionally they do)
122  *
123  * The second option, using @c le_mem_AssertAlloc(), is only used when the allocation should
124  * never fail, by design; a failure to allocate a block is a fatal error.
125  * This isn't often used, but can save a lot of boilerplate error checking code.
126  *
127  * The third option, @c using le_mem_ForceAlloc(), is the one that gets used most often.
128  * It allows developers to avoid writing error checking code, because the allocation will
129  * essentially never fail because it's handled inside the memory allocator. It also
130  * allows developers to defer fine tuning their pool sizes until after they get things working.
131  * Later, they check the logs for pool size usage, and then modify their pool sizes accordingly.
132  * If a particular pool is continually growing, it's a good indication there's a
133  * memory leak. This permits seeing exactly what objects are being leaked. If certain debug
134  * options are turned on, they can even find out which line in which file allocated the blocks
135  * being leaked.
136  *
137  *
138  * @section mem_releasing Releasing Back Into a Pool
139  *
140  * Releasing memory back to a pool never fails, so there's no need to check a return code.
141  * Also, each object knows which pool it came from, so the code that releases the object doesn't have to care.
142  * All it has to do is call @c le_mem_Release() and pass a pointer to the object to be released.
143  *
144  * The critical thing to remember is that once an object has been released, it
145  * <b> must never be accessed again </b>. Here is a <b> very bad code example</b>:
146  * @code
147  * Point_t* pointPtr = le_mem_ForceAlloc(PointPool);
148  * pointPtr->x = 5;
149  * pointPtr->y = 10;
150  * le_mem_Release(pointPtr);
151  * printf("Point is at position (%d, %d).\n", pointPtr->x, pointPtr->y);
152  * @endcode
153  *
154  *
155  * @section mem_ref_counting Reference Counting
156  *
157  * Reference counting is a powerful feature of our memory pools. Here's how it works:
158  * - Every object allocated from a pool starts with a reference count of 1.
159  * - Whenever someone calls le_mem_AddRef() on an object, its reference count is incremented by 1.
160  * - When it's released, its reference count is decremented by 1.
161  * - When its reference count reaches zero, it's destroyed (i.e., its memory is released back into the pool.)
162  *
163  * This allows one function to:
164  * - create an object.
165  * - work with it.
166  * - increment its reference count and pass a pointer to the object to another function (or thread, data structure, etc.).
167  * - work with it some more.
168  * - release the object without having to worry about when the other function is finished with it.
169  *
170  * The other function also releases the object when it's done with it. So, the object will
171  * exist until both functions are done.
172  *
173  * If there are multiple threads involved, be careful to protect the shared
174  * object from race conditions(see the @ref mem_threading).
175  *
176  * Another great advantage of reference counting is it enables @ref mem_destructors.
177  *
178  * @note le_mem_GetRefCount() can be used to check the current reference count on an object.
179  *
180  * @section mem_destructors Destructors
181  *
182  * Destructors are a powerful feature of C++. Anyone who has any non-trivial experience with C++ has
183  * used them. Because C was created before object-oriented programming was around, there's
184  * no native language support for destructors in C. Object-oriented design is still possible
185  * and highly desireable even when the programming is done in C.
186  *
187  * In Legato, it's possible to call @c le_mem_SetDestructor() to attach a function to a memory pool
188  * to be used as a destructor for objects allocated from that pool. If a pool has a destructor,
189  * whenever the reference count reaches zero for an object allocated from that pool,
190  * the pool's destructor function will pass a pointer to that object. After
191  * the destructor returns, the object will be fully destroyed, and its memory will be released back
192  * into the pool for later reuse by another object.
193  *
194  * Here's a destructor code sample:
195  * @code
196  * static void PointDestructor(void* objPtr)
197  * {
198  * Point_t* pointPtr = objPtr;
199  *
200  * printf("Destroying point (%d, %d)\n", pointPtr->x, pointPtr->y);
201  *
202  * @todo Add more to sample.
203  * }
204  *
205  * int xx_pt_ProcessStart(void)
206  * {
207  * PointPool = le_mem_CreatePool(sizeof(Point_t));
208  * le_mem_ExpandPool(PointPool, MAX_POINTS);
209  * le_mem_SetDestructor(PointPool, PointDestructor);
210  * return SUCCESS;
211  * }
212  *
213  * static void DeletePointList(Point_t** pointList, size_t numPoints)
214  * {
215  * size_t i;
216  * for (i = 0; i < numPoints; i++)
217  * {
218  * le_mem_Release(pointList[i]);
219  * }
220  * }
221  * @endcode
222  *
223  * In this sample, when DeletePointList() is called (with a pointer to an array of pointers
224  * to Point_t objects with reference counts of 1), each of the objects in the pointList is
225  * released. This causes their reference counts to hit 0, which triggers executing
226  * PointDestructor() for each object in the pointList, and the "Destroying point..." message will
227  * be printed for each.
228  *
229  *
230  * @section mem_stats Statistics
231  *
232  * Some statistics are gathered for each memory pool:
233  * - Number of allocations.
234  * - Number of currently free objects.
235  * - Number of overflows (times that le_mem_ForceAlloc() had to expand the pool).
236  *
237  * Statistics (and other pool properties) can be checked using functions:
238  * - @c le_mem_GetStats()
239  * - @c le_mem_GetObjectCount()
240  * - @c le_mem_GetObjectSize()
241  *
242  * Statistics are fetched together atomically using a single function call.
243  * This prevents inconsistencies between them if in a multi-threaded program.
244  *
245  * If you don't have a reference to a specified pool, but you have the name of the pool, you can
246  * get a reference to the pool using @c le_mem_FindPool().
247  *
248  * In addition to programmatically fetching these, they're also available through the
249  * "poolstat" console command (unless your process's main thread is blocked).
250  *
251  * To reset the pool statistics, use @c le_mem_ResetStats().
252  *
253  * @section mem_diagnostics Diagnostics
254  *
255  * The memory system also supports two different forms of diagnostics. Both are enabled by setting
256  * the appropriate KConfig options when building the framework.
257  *
258  * The first of these options is @ref MEM_TRACE. When you enable @ref MEM_TRACE every pool is given
259  * a tracepoint with the name of the pool on creation.
260  *
261  * For instance, the configTree node pool is called, "configTree.nodePool". So to enable a trace of
262  * all config tree node creation and deletion one would use the log tool as follows:
263  *
264  * @code
265  * $ log trace configTree.nodePool
266  * @endcode
267  *
268  * The second diagnostic build flag is @ref MEM_POOLS. When @ref MEM_POOLS is disabled, the pools
269  * are disabled and instead malloc and free are directly used. Thus enabling the use of tools
270  * like Valgrind.
271  *
272  * @section mem_threading Multi-Threading
273  *
274  * All functions in this API are <b> thread-safe, but not async-safe </b>. The objects
275  * allocated from pools are not inherently protected from races between threads.
276  *
277  * Allocating and releasing objects, checking stats, incrementing reference
278  * counts, etc. can all be done from multiple threads (excluding signal handlers) without having
279  * to worry about corrupting the memory pools' hidden internal data structures.
280  *
281  * There's no magical way to prevent different threads from interferring with each other
282  * if they both access the @a contents of the same object at the same time.
283  *
284  * The best way to prevent multi-threaded race conditions is simply don't share data between
285  * threads. If multiple threads must access the same data structure, then mutexes, semaphores,
286  * or similar methods should be used to @a synchronize threads and avoid
287  * data structure corruption or thread misbehaviour.
288  *
289  * Although memory pools are @a thread-safe, they are not @a async-safe. This means that memory pools
290  * @a can be corrupted if they are accessed by a signal handler while they are being accessed
291  * by a normal thread. To be safe, <b> don't call any memory pool functions from within a signal handler. </b>
292  *
293  * One problem using destructor functions in a
294  * multi-threaded environment is that the destructor function modifies a data structure shared
295  * between threads, so it's easy to forget to synchronize calls to @c le_mem_Release() with other code
296  * accessing the data structure. If a mutex is used to coordinate access to
297  * the data structure, then the mutex must be held by the thread that calls le_mem_Release() to
298  * ensure there's no other thread accessing the data structure when the destructor runs.
299  *
300  * @section mem_pool_sizes Managing Pool Sizes
301  *
302  * We know it's possible to have pools automatically expand
303  * when they are exhausted, but we don't really want that to happen normally.
304  * Ideally, the pools should be fully allocated to their maximum sizes at start-up so there aren't
305  * any surprises later when certain feature combinations cause the
306  * system to run out of memory in the field. If we allocate everything we think
307  * is needed up-front, then we are much more likely to uncover any memory shortages during
308  * testing, before it's in the field.
309  *
310  * Choosing the right size for your pools correctly at start-up is easy to do if there is a maximum
311  * number of fixed, external @a things that are being represented by the objects being allocated
312  * from the pool. If the pool holds "call objects" representing phone calls over a T1
313  * carrier that will never carry more than 24 calls at a time, then it's obvious that you need to
314  * size your call object pool at 24.
315  *
316  * Other times, it's not so easy to choose the pool size like
317  * code to be reused in different products or different configurations that have different
318  * needs. In those cases, you still have a few options:
319  *
320  * - At start-up, query the operating environment and base the pool sizes.
321  * - Read a configuration setting from a file or other configuration data source.
322  * - Use a build-time configuration setting.
323  *
324  * The build-time configuration setting is the easiest, and generally requires less
325  * interaction between components at start-up simplifying APIs
326  * and reducing boot times.
327  *
328  * If the pool size must be determined at start-up, use @c le_mem_ExpandPool().
329  * Perhaps there's a service-provider module designed to allocate objects on behalf
330  * of client. It can have multiple clients at the same time, but it doesn't know how many clients
331  * or what their resource needs will be until the clients register with it at start-up. We'd want
332  * those clients to be as decoupled from each other as possible (i.e., we want the clients know as little
333  * as possible about each other); we don't want the clients to get together and add up all
334  * their needs before telling the service-provider. We'd rather have the clients independently
335  * report their own needs to the service-provider. Also, we don't want each client to have to wait
336  * for all the other clients to report their needs before starting to use
337  * the services offered by the service-provider. That would add more complexity to the interactions
338  * between the clients and the service-provider.
339  *
340  * This is what should happen when the service-provider can't wait for all clients
341  * to report their needs before creating the pool:
342  * - When the service-provider starts up, it creates an empty pool.
343  * - Whenever a client registers itself with the service-provider, the client can tell the
344  * service-provider what its specific needs are, and the service-provider can expand its
345  * object pool accordingly.
346  * - Since registrations happen at start-up, pool expansion occurs
347  * at start-up, and testing will likely find any pool sizing before going into the field.
348  *
349  * Where clients dynamically start and stop during runtime in response
350  * to external events (e.g., when someone is using the device's Web UI), we still have
351  * a problem because we can't @a shrink pools or delete pools when clients go away. This is where
352  * @ref mem_sub_pools is useful.
353  *
354  * @section mem_sub_pools Sub-Pools
355  *
356  * Essentially, a Sub-Pool is a memory pool that gets its blocks from another pool (the super-pool).
357  * Sub Pools @a can be deleted, causing its blocks to be released back into the super-pool.
358  *
359  * This is useful when a service-provider module needs to handle clients that
360  * dynamically pop into existence and later disappear again. When a client attaches to the service
361  * and says it will probably need a maximum of X of the service-provider's resources, the
362  * service provider can set aside that many of those resources in a sub-pool for that client.
363  * If that client goes over its limit, the sub-pool will log a warning message.
364  *
365  * The problem of sizing the super-pool correctly at start-up still exists,
366  * so what's the point of having a sub-pool, when all of the resources could just be allocated from
367  * the super-pool?
368  *
369  * The benefit is really gained in troubleshooting. If client A, B, C, D and E are
370  * all behaving nicely, but client F is leaking resources, the sub-pool created
371  * on behalf of client F will start warning about the memory leak; time won't have to be
372  * wasted looking at clients A through E to rule them out.
373  *
374  * To create a sub-pool, call @c le_mem_CreateSubPool(). It takes a reference to the super-pool
375  * and the number of objects to move to the sub-pool, and it returns a reference to the new sub-pool.
376  *
377  * To delete a sub-pool, call @c le_mem_DeleteSubPool(). Do not try to use it to delete a pool that
378  * was created using le_mem_CreatePool(). It's only for sub-pools created using le_mem_CreateSubPool().
379  * Also, it's @b not okay to delete a sub-pool while there are still blocks allocated from it, or
380  * if it has any sub-pools. You'll see errors in your logs if you do that.
381  *
382  * Sub-Pools automatically inherit their parent's destructor function.
383  *
384  * @section mem_reduced_pools Reduced-size pools
385  *
386  * One problem that occurs with memory pools is where objects of different sizes need to be
387  * stored. A classic example is strings -- the longest string an application needs to be able
388  * to handle may be much longer than the typical string size. In this case a lot of memory
389  * will be wasted with standard memory pools, since all objects allocated from the pool will
390  * be the size of the longest possible object.
391  *
392  * The solution is to use reduced-size pools. These are a kind of sub-pool where the size
393  * of the object in the sub-pool is different from the size of the object in the super-pool.
394  * This way multiple blocks from the sub-pool can be stored in a single block of the super-pool.
395  *
396  * Reduced-size pools have some limitations:
397  *
398  * - Each block in the super-pool is divided up to create blocks in the subpool. So subpool
399  * blocks sizes must be less than half the size of the super-pool block size. An attempt to
400  * create a pool with a larger block size will just return a reference to the super-pool.
401  * - Due overhead, each block actually requires 8-80 bytes more space than requested.
402  * There is little point in subdividing pools < 4x overhead, or ~300 bytes in the default
403  * configuration. Note the exact amount of overhead depends on the size of the guard bands
404  * and the size of pointer on your target.
405  * - Blocks used by the reduced pool are permanently moved from the super-pool to the reduced
406  * pool. This must be taken into account when sizing the super-pool.
407  *
408  * Example 1:
409  *
410  * A network service needs to allocate space for packets received over a network. It should
411  * Typical packet length is up to 200 bytes, but occasional packets may be up to 1500 bytes. The
412  * service needs to be able to queue at least 32 packets, up to 5 of which can be 1500 bytes.
413  * Two pools are used: A pool of 12 objects 1500 bytes in size, and a reduced-size pool of 32
414  * objects 200 bytes in size (280 bytes with overhead). Seven objects from the superpool are
415  * used to store reduced-size objects. This represents a memory savings of 60% compared with
416  * a pool of 32 1500 byte objects.
417  *
418  * Example 2:
419  *
420  * An application builds file paths which can be from 16-70 bytes. Only three such paths can be
421  * created at a time, but they can be any size. In this case it is better to just create
422  * a single pool of three 70-byte objects. Most of the potential space gains would be consumed
423  * by overhead. Even if this was not the case, the super pool still needs three free objects
424  * in addition to the objects required by the subpool, so there is no space savings.
425  *
426  * To create a reduced-size pool, use @c le_mem_CreateReducedPool(). It takes a reference to the
427  * super-pool, the initial number of objects in the sub-pool, and size of an object in the sub-pool
428  * compared with the parent pool, and it returns a reference to the new sub-pool.
429  *
430  * Reduced-size pools are deleted using @c le_mem_DeleteSubPool() like other sub-pools.
431  *
432  * To help the programmer pick the right pool to allocate from, reduced-size pools provide
433  * @c le_mem_TryVarAlloc(), @c le_mem_AssertVarAlloc() and @c le_mem_ForceVarAlloc() functions.
434  * In addition to the pool these take the object size to allocate. If this size is larger than
435  * the pool's object size and the pool is a reduced-size pool, and there is a parent pool
436  * large enough for this object, it will allocate the object from the parent pool instead.
437  * If no parent pool is large enough, the program will exit.
438  *
439  * You can call @c le_mem_GetBlockSize() to get the actual size of the object returned by
440  * one of these functions.
441  *
442  * As with other sub-pools, they cannot be deleted while any blocks are allocated from the pool,
443  * or it has any sub-pools. Reduced-size pools also automatically inherit their parent's
444  * destructor function.
445  *
446  * <HR>
447  *
448  * Copyright (C) Sierra Wireless Inc.
449  */
450 
451 //--------------------------------------------------------------------------------------------------
452 /** @file le_mem.h
453  *
454  * Legato @ref c_memory include file.
455  *
456  * Copyright (C) Sierra Wireless Inc.
457  *
458  */
459 //--------------------------------------------------------------------------------------------------
460 
461 #ifndef LEGATO_MEM_INCLUDE_GUARD
462 #define LEGATO_MEM_INCLUDE_GUARD
463 
464 #ifndef LE_COMPONENT_NAME
465 # define LE_COMPONENT_NAME
466 #endif
467 
468 //--------------------------------------------------------------------------------------------------
469 /**
470  * Prototype for destructor functions.
471  *
472  * @param objPtr Pointer to the object where reference count has reached zero. After the destructor
473  * returns this object's memory will be released back into the pool (and this pointer
474  * will become invalid).
475  *
476  * @return Nothing.
477  *
478  * See @ref mem_destructors for more information.
479  */
480 //--------------------------------------------------------------------------------------------------
481 typedef void (*le_mem_Destructor_t)
482 (
483  void* objPtr ///< see parameter documentation in comment above.
484 );
485 
486 // Max memory pool name bytes -- must match definition in limit.h
487 #define LE_MEM_LIMIT_MAX_MEM_POOL_NAME_BYTES 32
488 
489 //--------------------------------------------------------------------------------------------------
490 /**
491  * Definition of a memory pool.
492  *
493  * @note This should not be used directly. To create a memory pool use either le_mem_CreatePool()
494  * or LE_MEM_DEFINE_STATIC_POOL()/le_mem_InitStaticPool().
495  */
496 //--------------------------------------------------------------------------------------------------
497 typedef struct le_mem_Pool
498 {
499  le_dls_Link_t poolLink; ///< This pool's link in the list of memory pools.
500  struct le_mem_Pool* superPoolPtr; ///< A pointer to our super pool if we are a sub-pool. NULL
501  /// if we are not a sub-pool.
502 #if LE_CONFIG_MEM_POOL_STATS
503  // These members go before LE_CONFIG_MEM_POOLS so numAllocations will always be aligned, even on
504  // 32-bit architectures, even when LE_CONFIG_MEM_POOLS is not declared
505  size_t numOverflows; ///< Number of times le_mem_ForceAlloc() had to expand pool.
506  uint64_t numAllocations; ///< Total number of times an object has been allocated
507  /// from this pool.
508  size_t maxNumBlocksUsed; ///< Maximum number of allocated blocks at any one time.
509 #endif
510 #if LE_CONFIG_MEM_POOLS
511  le_sls_List_t freeList; ///< List of free memory blocks.
512 #endif
513 
514  size_t userDataSize; ///< Size of the object requested by the client in bytes.
515  size_t blockSize; ///< Number of bytes in a block, including all overhead.
516  size_t totalBlocks; ///< Total number of blocks in this pool including free
517  /// and allocated blocks.
518  size_t numBlocksInUse; ///< Number of currently allocated blocks.
519  size_t numBlocksToForce; ///< Number of blocks that is added when Force Alloc
520  /// expands the pool.
521 #if LE_CONFIG_MEM_TRACE
522  le_log_TraceRef_t memTrace; ///< If tracing is enabled, keeps track of a trace object
523  ///< for this pool.
524 #endif
525 
526  le_mem_Destructor_t destructor; ///< The destructor for objects in this pool.
527 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
528  char name[LE_MEM_LIMIT_MAX_MEM_POOL_NAME_BYTES]; ///< Name of the pool.
529 #endif
530 }
532 
533 
534 //--------------------------------------------------------------------------------------------------
535 /**
536  * Objects of this type are used to refer to a memory pool created using either
537  * le_mem_CreatePool() or le_mem_CreateSubPool().
538  */
539 //--------------------------------------------------------------------------------------------------
540 typedef struct le_mem_Pool* le_mem_PoolRef_t;
541 
542 
543 //--------------------------------------------------------------------------------------------------
544 /**
545  * List of memory pool statistics.
546  */
547 //--------------------------------------------------------------------------------------------------
548 typedef struct
549 {
550  size_t numBlocksInUse; ///< Number of currently allocated blocks.
551  size_t maxNumBlocksUsed; ///< Maximum number of allocated blocks at any one time.
552  size_t numOverflows; ///< Number of times le_mem_ForceAlloc() had to expand the pool.
553  uint64_t numAllocs; ///< Number of times an object has been allocated from this pool.
554  size_t numFree; ///< Number of free objects currently available in this pool.
555 }
557 
558 
559 #if LE_CONFIG_MEM_TRACE
560  //----------------------------------------------------------------------------------------------
561  /**
562  * Internal function used to retrieve a pool handle for a given pool block.
563  */
564  //----------------------------------------------------------------------------------------------
565  le_mem_PoolRef_t _le_mem_GetBlockPool
566  (
567  void* objPtr ///< [IN] Pointer to the object we're finding a pool for.
568  );
569 
570  typedef void* (*_le_mem_AllocFunc_t)(le_mem_PoolRef_t pool);
571 
572  //----------------------------------------------------------------------------------------------
573  /**
574  * Internal function used to call a memory allocation function and trace its call site.
575  */
576  //----------------------------------------------------------------------------------------------
577  void* _le_mem_AllocTracer
578  (
579  le_mem_PoolRef_t pool, ///< [IN] The pool activity we're tracing.
580  _le_mem_AllocFunc_t funcPtr, ///< [IN] Pointer to the mem function in question.
581  const char* poolFunction, ///< [IN] The pool function being called.
582  const char* file, ///< [IN] The file the call came from.
583  const char* callingfunction, ///< [IN] The function calling into the pool.
584  size_t line ///< [IN] The line in the function where the call
585  /// occurred.
586  );
587 
588  //----------------------------------------------------------------------------------------------
589  /**
590  * Internal function used to call a variable memory allocation function and trace its call site.
591  */
592  //----------------------------------------------------------------------------------------------
593  void* _le_mem_VarAllocTracer
594  (
595  le_mem_PoolRef_t pool, ///< [IN] The pool activity we're tracing.
596  size_t size, ///< [IN] The size of block to allocate
597  _le_mem_AllocFunc_t funcPtr, ///< [IN] Pointer to the mem function in question.
598  const char* poolFunction, ///< [IN] The pool function being called.
599  const char* file, ///< [IN] The file the call came from.
600  const char* callingfunction, ///< [IN] The function calling into the pool.
601  size_t line ///< [IN] The line in the function where the call
602  /// occurred.
603  );
604 
605  //----------------------------------------------------------------------------------------------
606  /**
607  * Internal function used to trace memory pool activity.
608  */
609  //----------------------------------------------------------------------------------------------
610  void _le_mem_Trace
611  (
612  le_mem_PoolRef_t pool, ///< [IN] The pool activity we're tracing.
613  const char* file, ///< [IN] The file the call came from.
614  const char* callingfunction, ///< [IN] The function calling into the pool.
615  size_t line, ///< [IN] The line in the function where the call
616  /// occurred.
617  const char* poolFunction, ///< [IN] The pool function being called.
618  void* blockPtr ///< [IN] Block allocated/freed.
619  );
620 #endif
621 
622 
623 /// @cond HIDDEN_IN_USER_DOCS
624 //--------------------------------------------------------------------------------------------------
625 /**
626  * Internal function used to implement le_mem_InitStaticPool() with automatic component scoping
627  * of pool names.
628  */
629 //--------------------------------------------------------------------------------------------------
630 le_mem_PoolRef_t _le_mem_InitStaticPool
631 (
632  const char* componentName, ///< [IN] Name of the component.
633  const char* name, ///< [IN] Name of the pool inside the component.
634  size_t numBlocks, ///< [IN] Number of members in the pool by default
635  size_t objSize, ///< [IN] Size of the individual objects to be allocated from this pool
636  /// (in bytes), e.g., sizeof(MyObject_t).
637  le_mem_Pool_t* poolPtr, ///< [IN] Pointer to pre-allocated pool header.
638  void* poolDataPtr ///< [IN] Pointer to pre-allocated pool data.
639 );
640 /// @endcond
641 
642 
643 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
644 //--------------------------------------------------------------------------------------------------
645 /** @cond HIDDEN_IN_USER_DOCS
646  *
647  * Internal function used to implement le_mem_CreatePool() with automatic component scoping
648  * of pool names.
649  */
650 //--------------------------------------------------------------------------------------------------
651 le_mem_PoolRef_t _le_mem_CreatePool
652 (
653  const char* componentName, ///< [IN] Name of the component.
654  const char* name, ///< [IN] Name of the pool inside the component.
655  size_t objSize ///< [IN] Size of the individual objects to be allocated from this pool
656  /// (in bytes), e.g., sizeof(MyObject_t).
657 );
658 /// @endcond
659 //--------------------------------------------------------------------------------------------------
660 /**
661  * Creates an empty memory pool.
662  *
663  * @return
664  * Reference to the memory pool object.
665  *
666  * @note
667  * On failure, the process exits, so you don't have to worry about checking the returned
668  * reference for validity.
669  */
670 //--------------------------------------------------------------------------------------------------
671 static inline le_mem_PoolRef_t le_mem_CreatePool
672 (
673  const char* name, ///< [IN] Name of the pool inside the component.
674  size_t objSize ///< [IN] Size of the individual objects to be allocated from this pool
675  /// (in bytes), e.g., sizeof(MyObject_t).
676 )
677 {
678  return _le_mem_CreatePool(STRINGIZE(LE_COMPONENT_NAME), name, objSize);
679 }
680 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
681 //--------------------------------------------------------------------------------------------------
682 /** @cond HIDDEN_IN_USER_DOCS
683  *
684  * Internal function used to implement le_mem_CreatePool() with automatic component scoping
685  * of pool names.
686  */
687 //--------------------------------------------------------------------------------------------------
688 le_mem_PoolRef_t _le_mem_CreatePool
689 (
690  size_t objSize ///< [IN] Size of the individual objects to be allocated from this pool
691  /// (in bytes), e.g., sizeof(MyObject_t).
692 );
693 /// @endcond
694 //--------------------------------------------------------------------------------------------------
695 /**
696  * Creates an empty memory pool.
697  *
698  * @return
699  * Reference to the memory pool object.
700  *
701  * @note
702  * On failure, the process exits, so you don't have to worry about checking the returned
703  * reference for validity.
704  */
705 //--------------------------------------------------------------------------------------------------
706 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_CreatePool
707 (
708  const char* name, ///< [IN] Name of the pool inside the component.
709  size_t objSize ///< [IN] Size of the individual objects to be allocated from this pool
710  /// (in bytes), e.g., sizeof(MyObject_t).
711 )
712 {
713  return _le_mem_CreatePool(objSize);
714 }
715 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
716 
717 //--------------------------------------------------------------------------------------------------
718 /**
719  * Number of words in a memory pool, given number of blocks and object size.
720  *
721  * @note Only used internally
722  */
723 //--------------------------------------------------------------------------------------------------
724 #define LE_MEM_POOL_WORDS(numBlocks, objSize) \
725  ((numBlocks)*(((sizeof(le_mem_Pool_t*) + sizeof(size_t)) /* sizeof(MemBlock_t) */ + \
726  (((objSize)<sizeof(le_sls_Link_t))?sizeof(le_sls_Link_t):(objSize))+ \
727  sizeof(uint32_t)*LE_CONFIG_NUM_GUARD_BAND_WORDS*2+ \
728  sizeof(size_t) - 1) / sizeof(size_t)))
729 
730 //--------------------------------------------------------------------------------------------------
731 /**
732  * Calculate the number of blocks for a pool.
733  *
734  * @param name Pool name.
735  * @param def Default number of blocks.
736  *
737  * @return Number of blocks, either the value provided by <name>_POOL_SIZE if it is defined, or
738  * <def>. To be valid, <name>_POOL_SIZE must be defined as ,<value> (note the leading
739  * comma).
740  */
741 //--------------------------------------------------------------------------------------------------
742 #define LE_MEM_BLOCKS(name, def) (LE_DEFAULT(CAT(_mem_, CAT(name, _POOL_SIZE)), (def)))
743 
744 //--------------------------------------------------------------------------------------------------
745 /**
746  * Declare variables for a static memory pool.
747  *
748  * In a static memory pool initial pool memory is statically allocated at compile time, ensuring
749  * pool can be created with at least some elements. This is especially valuable on embedded
750  * systems.
751  *
752  * @param name Pool name.
753  * @param numBlocks Default number of blocks. This can be overriden in components using the "pools"
754  * directive.
755  * @param objSize Size of each block in the pool.
756  */
757 /*
758  * Internal Note: size_t is used instead of uint8_t to ensure alignment on platforms where
759  * alignment matters.
760  */
761 //--------------------------------------------------------------------------------------------------
762 #if LE_CONFIG_MEM_POOLS
763 # define LE_MEM_DEFINE_STATIC_POOL(name, numBlocks, objSize) \
764  static le_mem_Pool_t _mem_##name##Pool; \
765  static size_t _mem_##name##Data[LE_MEM_POOL_WORDS(LE_MEM_BLOCKS(name, numBlocks), objSize)]
766 #else
767 # define LE_MEM_DEFINE_STATIC_POOL(name, numBlocks, objSize) \
768  static le_mem_Pool_t _mem_##name##Pool
769 #endif
770 
771 //--------------------------------------------------------------------------------------------------
772 /**
773  * Declare variables for a static memory pool, must specify which object section the variable goes
774  * into
775  *
776  * By default static memory will the assigned to the bss or data section of the final object.
777  * This macro tells the linker to assign to variable to a specific section, sectionName.
778  * Essentially a "__attribute__((section("sectionName")))" will be added after the variable
779  * declaration.
780  *
781  *
782  * @param name Pool name.
783  * @param numBlocks Default number of blocks. This can be overridden in components using the "pools"
784  * directive.
785  * @param objSize Size of each block in the pool.
786  * @param sectionName __attribute__((section("section"))) will be added to the pool declaration so the
787  memory is associated with a the specific section instead of bss, data,..
788  */
789 /*
790  * Internal Note: size_t is used instead of uint8_t to ensure alignment on platforms where
791  * alignment matters.
792  */
793 //--------------------------------------------------------------------------------------------------
794 #if LE_CONFIG_MEM_POOLS
795 # define LE_MEM_DEFINE_STATIC_POOL_IN_SECTION(name, numBlocks, objSize, sectionName) \
796  static le_mem_Pool_t _mem_##name##Pool __attribute__((section(sectionName))); \
797  static size_t _mem_##name##Data[LE_MEM_POOL_WORDS( \
798  LE_MEM_BLOCKS(name, numBlocks), objSize)] __attribute__((section(sectionName)))
799 #else
800 # define LE_MEM_DEFINE_STATIC_POOL_IN_SECTION(name, numBlocks, objSize, sectionName) \
801  static le_mem_Pool_t _mem_##name##Pool __attribute__((section(sectionName)));
802 #endif
803 
804 //--------------------------------------------------------------------------------------------------
805 /**
806  * Initialize an empty static memory pool.
807  *
808  * @param name Pool name.
809  * @param numBlocks Default number of blocks. This can be overriden in components using the "pools"
810  * directive.
811  * @param objSize Size of each block in the pool.
812  *
813  * @return
814  * Reference to the memory pool object.
815  *
816  * @note
817  * This function cannot fail.
818  */
819 //--------------------------------------------------------------------------------------------------
820 #if LE_CONFIG_MEM_POOLS
821 # define le_mem_InitStaticPool(name, numBlocks, objSize) \
822  (inline_static_assert( \
823  sizeof(_mem_##name##Data) == \
824  sizeof(size_t[LE_MEM_POOL_WORDS(LE_MEM_BLOCKS(name, numBlocks), objSize)]), \
825  "initial pool size does not match definition"), \
826  _le_mem_InitStaticPool(STRINGIZE(LE_COMPONENT_NAME), #name, \
827  LE_MEM_BLOCKS(name, numBlocks), (objSize), &_mem_##name##Pool, _mem_##name##Data))
828 #else
829 # define le_mem_InitStaticPool(name, numBlocks, objSize) \
830  _le_mem_InitStaticPool(STRINGIZE(LE_COMPONENT_NAME), #name, \
831  LE_MEM_BLOCKS(name, numBlocks), (objSize), &_mem_##name##Pool, NULL)
832 #endif
833 
834 //--------------------------------------------------------------------------------------------------
835 /**
836  * Expands the size of a memory pool.
837  *
838  * @return Reference to the memory pool object (the same value passed into it).
839  *
840  * @note On failure, the process exits, so you don't have to worry about checking the returned
841  * reference for validity.
842  */
843 //--------------------------------------------------------------------------------------------------
844 le_mem_PoolRef_t le_mem_ExpandPool
845 (
846  le_mem_PoolRef_t pool, ///< [IN] Pool to be expanded.
847  size_t numObjects ///< [IN] Number of objects to add to the pool.
848 );
849 
850 
851 
852 #if !LE_CONFIG_MEM_TRACE
853  //----------------------------------------------------------------------------------------------
854  /**
855  * Attempts to allocate an object from a pool.
856  *
857  * @return
858  * Pointer to the allocated object, or NULL if the pool doesn't have any free objects
859  * to allocate.
860  */
861  //----------------------------------------------------------------------------------------------
862  void* le_mem_TryAlloc
863  (
864  le_mem_PoolRef_t pool ///< [IN] Pool from which the object is to be allocated.
865  );
866 #else
867  /// @cond HIDDEN_IN_USER_DOCS
868  void* _le_mem_TryAlloc(le_mem_PoolRef_t pool);
869  /// @endcond
870 
871 # define le_mem_TryAlloc(pool) \
872  _le_mem_AllocTracer(pool, \
873  _le_mem_TryAlloc, \
874  "le_mem_TryAlloc", \
875  STRINGIZE(LE_FILENAME), \
876  __FUNCTION__, \
877  __LINE__)
878 
879 #endif
880 
881 
882 #if !LE_CONFIG_MEM_TRACE
883  //----------------------------------------------------------------------------------------------
884  /**
885  * Allocates an object from a pool or logs a fatal error and terminates the process if the pool
886  * doesn't have any free objects to allocate.
887  *
888  * @return Pointer to the allocated object.
889  *
890  * @note On failure, the process exits, so you don't have to worry about checking the
891  * returned pointer for validity.
892  */
893  //----------------------------------------------------------------------------------------------
894  void* le_mem_AssertAlloc
895  (
896  le_mem_PoolRef_t pool ///< [IN] Pool from which the object is to be allocated.
897  );
898 #else
899  /// @cond HIDDEN_IN_USER_DOCS
900  void* _le_mem_AssertAlloc(le_mem_PoolRef_t pool);
901  /// @endcond
902 
903 # define le_mem_AssertAlloc(pool) \
904  _le_mem_AllocTracer(pool, \
905  _le_mem_AssertAlloc, \
906  "le_mem_AssertAlloc", \
907  STRINGIZE(LE_FILENAME), \
908  __FUNCTION__, \
909  __LINE__)
910 #endif
911 
912 
913 #if !LE_CONFIG_MEM_TRACE
914  //----------------------------------------------------------------------------------------------
915  /**
916  * Allocates an object from a pool or logs a warning and expands the pool if the pool
917  * doesn't have any free objects to allocate.
918  *
919  * @return Pointer to the allocated object.
920  *
921  * @note On failure, the process exits, so you don't have to worry about checking the
922  * returned pointer for validity.
923  */
924  //----------------------------------------------------------------------------------------------
925  void* le_mem_ForceAlloc
926  (
927  le_mem_PoolRef_t pool ///< [IN] Pool from which the object is to be allocated.
928  );
929 #else
930  /// @cond HIDDEN_IN_USER_DOCS
931  void* _le_mem_ForceAlloc(le_mem_PoolRef_t pool);
932  /// @endcond
933 
934 # define le_mem_ForceAlloc(pool) \
935  _le_mem_AllocTracer(pool, \
936  _le_mem_ForceAlloc, \
937  "le_mem_ForceAlloc", \
938  STRINGIZE(LE_FILENAME), \
939  __FUNCTION__, \
940  __LINE__)
941 #endif
942 
943 
944 #if !LE_CONFIG_MEM_TRACE
945  //----------------------------------------------------------------------------------------------
946  /**
947  * Attempts to allocate an object from a pool.
948  *
949  * @return
950  * Pointer to the allocated object, or NULL if the pool doesn't have any free objects
951  * to allocate.
952  */
953  //----------------------------------------------------------------------------------------------
954  void* le_mem_TryVarAlloc
955  (
956  le_mem_PoolRef_t pool, ///< [IN] Pool from which the object is to be allocated.
957  size_t size ///< [IN] The size of block to allocate
958  );
959 #else
960  /// @cond HIDDEN_IN_USER_DOCS
961  void* _le_mem_TryVarAlloc(le_mem_PoolRef_t pool, size_t size);
962  /// @endcond
963 
964 # define le_mem_TryVarAlloc(pool, size) \
965  _le_mem_VarAllocTracer(pool, \
966  size, \
967  _le_mem_TryVarAlloc, \
968  "le_mem_TryVarAlloc", \
969  STRINGIZE(LE_FILENAME), \
970  __FUNCTION__, \
971  __LINE__)
972 
973 #endif
974 
975 
976 #if !LE_CONFIG_MEM_TRACE
977  //----------------------------------------------------------------------------------------------
978  /**
979  * Allocates an object from a pool or logs a fatal error and terminates the process if the pool
980  * doesn't have any free objects to allocate.
981  *
982  * @return Pointer to the allocated object.
983  *
984  * @note On failure, the process exits, so you don't have to worry about checking the
985  * returned pointer for validity.
986  */
987  //----------------------------------------------------------------------------------------------
989  (
990  le_mem_PoolRef_t pool, ///< [IN] Pool from which the object is to be allocated.
991  size_t size ///< [IN] The size of block to allocate
992  );
993 #else
994  /// @cond HIDDEN_IN_USER_DOCS
995  void* _le_mem_AssertVarAlloc(le_mem_PoolRef_t pool, size_t size);
996  /// @endcond
997 
998 # define le_mem_AssertVarAlloc(pool, size) \
999  _le_mem_VarAllocTracer(pool, \
1000  size, \
1001  _le_mem_AssertVarAlloc, \
1002  "le_mem_AssertVarAlloc", \
1003  STRINGIZE(LE_FILENAME), \
1004  __FUNCTION__, \
1005  __LINE__)
1006 #endif
1007 
1008 
1009 #if !LE_CONFIG_MEM_TRACE
1010  //----------------------------------------------------------------------------------------------
1011  /**
1012  * Allocates an object from a pool or logs a warning and expands the pool if the pool
1013  * doesn't have any free objects to allocate.
1014  *
1015  * @return Pointer to the allocated object.
1016  *
1017  * @note On failure, the process exits, so you don't have to worry about checking the
1018  * returned pointer for validity.
1019  */
1020  //----------------------------------------------------------------------------------------------
1021  void* le_mem_ForceVarAlloc
1022  (
1023  le_mem_PoolRef_t pool, ///< [IN] Pool from which the object is to be allocated.
1024  size_t size ///< [IN] The size of block to allocate
1025  );
1026 #else
1027  /// @cond HIDDEN_IN_USER_DOCS
1028  void* _le_mem_ForceVarAlloc(le_mem_PoolRef_t pool, size_t size);
1029  /// @endcond
1030 
1031 # define le_mem_ForceVarAlloc(pool, size) \
1032  _le_mem_VarAllocTracer(pool, \
1033  size, \
1034  _le_mem_ForceVarAlloc, \
1035  "le_mem_ForceVarAlloc", \
1036  STRINGIZE(LE_FILENAME), \
1037  __FUNCTION__, \
1038  __LINE__)
1039 #endif
1040 
1041 //--------------------------------------------------------------------------------------------------
1042 /**
1043  * Attempts to allocate an object from a pool using the configured allocation failure behaviour
1044  * (force or assert). Forced allocation will expand into the heap if the configured pool size is
1045  * exceeded, while assert allocation will abort the program with an error if the pool cannot satisfy
1046  * the request.
1047  *
1048  * @param pool Pool from which the object is to be allocated.
1049  *
1050  * @return Pointer to the allocated object.
1051  */
1052 //--------------------------------------------------------------------------------------------------
1053 #if LE_CONFIG_MEM_ALLOC_FORCE
1054 # define le_mem_Alloc(pool) le_mem_ForceAlloc(pool)
1055 #elif LE_CONFIG_MEM_ALLOC_ASSERT
1056 # define le_mem_Alloc(pool) le_mem_AssertAlloc(pool)
1057 #else
1058 # error "No supported allocation scheme selected!"
1059 #endif
1060 
1061 //--------------------------------------------------------------------------------------------------
1062 /**
1063  * Attempts to allocate a variably-sized object from a pool using the configured allocation failure
1064  * behaviour (force or assert). Forced allocation will expand into the heap if the configured pool
1065  * size is exceeded, while assert allocation will abort the program with an error if the pool cannot
1066  * satisfy the request.
1067  *
1068  * @param pool Pool from which the object is to be allocated.
1069  * @param size The size of block to allocate.
1070  *
1071  * @return Pointer to the allocated object.
1072  */
1073 //--------------------------------------------------------------------------------------------------
1074 #if LE_CONFIG_MEM_ALLOC_FORCE
1075 # define le_mem_VarAlloc(pool, size) le_mem_ForceVarAlloc((pool), (size))
1076 #elif LE_CONFIG_MEM_ALLOC_ASSERT
1077 # define le_mem_VarAlloc(pool, size) le_mem_AssertVarAlloc((pool), (size))
1078 #else
1079 # error "No supported allocation scheme selected!"
1080 #endif
1081 
1082 //--------------------------------------------------------------------------------------------------
1083 /**
1084  * Sets the number of objects that are added when le_mem_ForceAlloc expands the pool.
1085  *
1086  * @return
1087  * Nothing.
1088  *
1089  * @note
1090  * The default value is one.
1091  */
1092 //--------------------------------------------------------------------------------------------------
1094 (
1095  le_mem_PoolRef_t pool, ///< [IN] Pool to set the number of objects for.
1096  size_t numObjects ///< [IN] Number of objects that is added when
1097  /// le_mem_ForceAlloc expands the pool.
1098 );
1099 
1100 
1101 #if !LE_CONFIG_MEM_TRACE
1102  //----------------------------------------------------------------------------------------------
1103  /**
1104  * Releases an object. If the object's reference count has reached zero, it will be destructed
1105  * and its memory will be put back into the pool for later reuse.
1106  *
1107  * @return
1108  * Nothing.
1109  *
1110  * @warning
1111  * - <b>Don't EVER access an object after releasing it.</b> It might not exist anymore.
1112  * - If the object has a destructor accessing a data structure shared by multiple
1113  * threads, ensure you hold the mutex (or take other measures to prevent races) before
1114  * releasing the object.
1115  */
1116  //----------------------------------------------------------------------------------------------
1117  void le_mem_Release
1118  (
1119  void* objPtr ///< [IN] Pointer to the object to be released.
1120  );
1121 #else
1122  /// @cond HIDDEN_IN_USER_DOCS
1123  void _le_mem_Release(void* objPtr);
1124  /// @endcond
1125 
1126 # define le_mem_Release(objPtr) \
1127  _le_mem_Trace(_le_mem_GetBlockPool(objPtr), \
1128  STRINGIZE(LE_FILENAME), \
1129  __FUNCTION__, \
1130  __LINE__, \
1131  "le_mem_Release", \
1132  (objPtr)); \
1133  _le_mem_Release(objPtr);
1134 #endif
1135 
1136 
1137 #if !LE_CONFIG_MEM_TRACE
1138  //----------------------------------------------------------------------------------------------
1139  /**
1140  * Increments the reference count on an object by 1.
1141  *
1142  * See @ref mem_ref_counting for more information.
1143  *
1144  * @return
1145  * Nothing.
1146  */
1147  //----------------------------------------------------------------------------------------------
1148  void le_mem_AddRef
1149  (
1150  void* objPtr ///< [IN] Pointer to the object.
1151  );
1152 #else
1153  /// @cond HIDDEN_IN_USER_DOCS
1154  void _le_mem_AddRef(void* objPtr);
1155  /// @endcond
1156 
1157 # define le_mem_AddRef(objPtr) \
1158  _le_mem_Trace(_le_mem_GetBlockPool(objPtr), \
1159  STRINGIZE(LE_FILENAME), \
1160  __FUNCTION__, \
1161  __LINE__, \
1162  "le_mem_AddRef", \
1163  (objPtr)); \
1164  _le_mem_AddRef(objPtr);
1165 #endif
1166 
1167 //--------------------------------------------------------------------------------------------------
1168 /**
1169  * Fetches the size of a block (in bytes).
1170  *
1171  * @return
1172  * Object size, in bytes.
1173  */
1174 //--------------------------------------------------------------------------------------------------
1175 size_t le_mem_GetBlockSize
1176 (
1177  void* objPtr ///< [IN] Pointer to the object to get size of.
1178 );
1179 
1180 //----------------------------------------------------------------------------------------------
1181 /**
1182  * Fetches the reference count on an object.
1183  *
1184  * See @ref mem_ref_counting for more information.
1185  *
1186  * @warning If using this in a multi-threaded application that shares memory pool objects
1187  * between threads, steps must be taken to coordinate the threads (e.g., using a mutex)
1188  * to ensure that the reference count value fetched remains correct when it is used.
1189  *
1190  * @return
1191  * The reference count on the object.
1192  */
1193 //----------------------------------------------------------------------------------------------
1194 size_t le_mem_GetRefCount
1195 (
1196  void* objPtr ///< [IN] Pointer to the object.
1197 );
1198 
1199 
1200 //--------------------------------------------------------------------------------------------------
1201 /**
1202  * Sets the destructor function for a specified pool.
1203  *
1204  * See @ref mem_destructors for more information.
1205  *
1206  * @return
1207  * Nothing.
1208  */
1209 //--------------------------------------------------------------------------------------------------
1211 (
1212  le_mem_PoolRef_t pool, ///< [IN] The pool.
1213  le_mem_Destructor_t destructor ///< [IN] Destructor function.
1214 );
1215 
1216 
1217 //--------------------------------------------------------------------------------------------------
1218 /**
1219  * Fetches the statistics for a specified pool.
1220  *
1221  * @return
1222  * Nothing. Uses output parameter instead.
1223  */
1224 //--------------------------------------------------------------------------------------------------
1225 void le_mem_GetStats
1226 (
1227  le_mem_PoolRef_t pool, ///< [IN] Pool where stats are to be fetched.
1228  le_mem_PoolStats_t* statsPtr ///< [OUT] Pointer to where the stats will be stored.
1229 );
1230 
1231 
1232 //--------------------------------------------------------------------------------------------------
1233 /**
1234  * Resets the statistics for a specified pool.
1235  *
1236  * @return
1237  * Nothing.
1238  */
1239 //--------------------------------------------------------------------------------------------------
1240 void le_mem_ResetStats
1241 (
1242  le_mem_PoolRef_t pool ///< [IN] Pool where stats are to be reset.
1243 );
1244 
1245 
1246 //--------------------------------------------------------------------------------------------------
1247 /**
1248  * Gets the memory pool's name, including the component name prefix.
1249  *
1250  * If the pool were given the name "myPool" and the component that it belongs to is called
1251  * "myComponent", then the full pool name returned by this function would be "myComponent.myPool".
1252  *
1253  * @return
1254  * LE_OK if successful.
1255  * LE_OVERFLOW if the name was truncated to fit in the provided buffer.
1256  */
1257 //--------------------------------------------------------------------------------------------------
1259 (
1260  le_mem_PoolRef_t pool, ///< [IN] The memory pool.
1261  char* namePtr, ///< [OUT] Buffer to store the name of the memory pool.
1262  size_t bufSize ///< [IN] Size of the buffer namePtr points to.
1263 );
1264 
1265 
1266 //--------------------------------------------------------------------------------------------------
1267 /**
1268  * Checks if the specified pool is a sub-pool.
1269  *
1270  * @return
1271  * true if it is a sub-pool.
1272  * false if it is not a sub-pool.
1273  */
1274 //--------------------------------------------------------------------------------------------------
1275 bool le_mem_IsSubPool
1276 (
1277  le_mem_PoolRef_t pool ///< [IN] The memory pool.
1278 );
1279 
1280 
1281 //--------------------------------------------------------------------------------------------------
1282 /**
1283  * Fetches the number of objects a specified pool can hold (this includes both the number of
1284  * free and in-use objects).
1285  *
1286  * @return
1287  * Total number of objects.
1288  */
1289 //--------------------------------------------------------------------------------------------------
1290 size_t le_mem_GetObjectCount
1291 (
1292  le_mem_PoolRef_t pool ///< [IN] Pool where number of objects is to be fetched.
1293 );
1294 
1295 
1296 //--------------------------------------------------------------------------------------------------
1297 /**
1298  * Fetches the size of the objects in a specified pool (in bytes).
1299  *
1300  * @return
1301  * Object size, in bytes.
1302  */
1303 //--------------------------------------------------------------------------------------------------
1304 size_t le_mem_GetObjectSize
1305 (
1306  le_mem_PoolRef_t pool ///< [IN] Pool where object size is to be fetched.
1307 );
1308 
1309 
1310 //--------------------------------------------------------------------------------------------------
1311 /**
1312  * Fetches the total size of the object including all the memory overhead in a given pool (in bytes).
1313  *
1314  * @return
1315  * Total object memory size, in bytes.
1316  */
1317 //--------------------------------------------------------------------------------------------------
1319 (
1320  le_mem_PoolRef_t pool ///< [IN] The pool whose object memory size is to be fetched.
1321 );
1322 
1323 
1324 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
1325 //--------------------------------------------------------------------------------------------------
1326 /** @cond HIDDEN_IN_USER_DOCS
1327  *
1328  * Internal function used to implement le_mem_FindPool() with automatic component scoping
1329  * of pool names.
1330  */
1331 //--------------------------------------------------------------------------------------------------
1332 le_mem_PoolRef_t _le_mem_FindPool
1333 (
1334  const char* componentName, ///< [IN] Name of the component.
1335  const char* name ///< [IN] Name of the pool inside the component.
1336 );
1337 /// @endcond
1338 //--------------------------------------------------------------------------------------------------
1339 /**
1340  * Finds a pool based on the pool's name.
1341  *
1342  * @return
1343  * Reference to the pool, or NULL if the pool doesn't exist.
1344  */
1345 //--------------------------------------------------------------------------------------------------
1346 static inline le_mem_PoolRef_t le_mem_FindPool
1348  const char* name ///< [IN] Name of the pool inside the component.
1349 )
1350 {
1351  return _le_mem_FindPool(STRINGIZE(LE_COMPONENT_NAME), name);
1352 }
1353 #else
1354 //--------------------------------------------------------------------------------------------------
1355 /**
1356  * Finds a pool based on the pool's name.
1357  *
1358  * @return
1359  * Reference to the pool, or NULL if the pool doesn't exist.
1360  */
1361 //--------------------------------------------------------------------------------------------------
1362 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_FindPool
1363 (
1364  const char* name ///< [IN] Name of the pool inside the component.
1365 )
1366 {
1367  return NULL;
1368 }
1369 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
1370 
1371 
1372 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
1373 //--------------------------------------------------------------------------------------------------
1374 /** @cond HIDDEN_IN_USER_DOCS
1375  *
1376  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
1377  * of pool names.
1378  */
1379 //--------------------------------------------------------------------------------------------------
1380 le_mem_PoolRef_t _le_mem_CreateSubPool
1381 (
1382  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1383  const char* componentName, ///< [IN] Name of the component.
1384  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1385  /// sub-pool).
1386  size_t numObjects ///< [IN] Number of objects to take from the super-pool.
1387 );
1388 /// @endcond
1389 //--------------------------------------------------------------------------------------------------
1390 /**
1391  * Creates a sub-pool.
1392  *
1393  * See @ref mem_sub_pools for more information.
1394  *
1395  * @return
1396  * Reference to the sub-pool.
1397  */
1398 //--------------------------------------------------------------------------------------------------
1399 static inline le_mem_PoolRef_t le_mem_CreateSubPool
1401  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1402  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1403  /// sub-pool).
1404  size_t numObjects ///< [IN] Number of objects to take from the super-pool.
1405 )
1406 {
1407  return _le_mem_CreateSubPool(superPool, STRINGIZE(LE_COMPONENT_NAME), name, numObjects);
1408 }
1409 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
1410 //--------------------------------------------------------------------------------------------------
1411 /** @cond HIDDEN_IN_USER_DOCS
1412  *
1413  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
1414  * of pool names.
1415  */
1416 //--------------------------------------------------------------------------------------------------
1417 le_mem_PoolRef_t _le_mem_CreateSubPool
1418 (
1419  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1420  size_t numObjects ///< [IN] Number of objects to take from the super-pool.
1421 );
1422 /// @endcond
1423 //--------------------------------------------------------------------------------------------------
1424 /**
1425  * Creates a sub-pool.
1426  *
1427  * See @ref mem_sub_pools for more information.
1428  *
1429  * @return
1430  * Reference to the sub-pool.
1431  */
1432 //--------------------------------------------------------------------------------------------------
1433 LE_DECLARE_INLINE le_mem_PoolRef_t le_mem_CreateSubPool
1434 (
1435  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1436  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1437  /// sub-pool).
1438  size_t numObjects ///< [IN] Number of objects to take from the super-pool.
1439 )
1440 {
1441  return _le_mem_CreateSubPool(superPool, numObjects);
1442 }
1443 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
1444 
1445 
1446 #if LE_CONFIG_MEM_POOL_NAMES_ENABLED
1447 //--------------------------------------------------------------------------------------------------
1448 /** @cond HIDDEN_IN_USER_DOCS
1449  *
1450  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
1451  * of pool names.
1452  */
1453 //--------------------------------------------------------------------------------------------------
1454 le_mem_PoolRef_t _le_mem_CreateReducedPool
1455 (
1456  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1457  const char* componentName, ///< [IN] Name of the component.
1458  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1459  /// sub-pool).
1460  size_t numObjects, ///< [IN] Number of objects to take from the super-pool.
1461  size_t objSize ///< [IN] Minimum size of objects in the subpool.
1462 );
1463 /// @endcond
1464 //--------------------------------------------------------------------------------------------------
1465 /**
1466  * Creates a sub-pool of smaller objects.
1467  *
1468  * See @ref mem_reduced_pools for more information.
1469  *
1470  * @return
1471  * Reference to the sub-pool.
1472  */
1473 //--------------------------------------------------------------------------------------------------
1474 static inline le_mem_PoolRef_t le_mem_CreateReducedPool
1476  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1477  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1478  /// sub-pool).
1479  size_t numObjects, ///< [IN] Minimum number of objects in the subpool
1480  ///< by default.
1481  size_t objSize ///< [IN] Minimum size of objects in the subpool.
1482 )
1483 {
1484  return _le_mem_CreateReducedPool(superPool, STRINGIZE(LE_COMPONENT_NAME), name, numObjects, objSize);
1485 }
1486 #else /* if not LE_CONFIG_MEM_POOL_NAMES_ENABLED */
1487 //--------------------------------------------------------------------------------------------------
1488 /** @cond HIDDEN_IN_USER_DOCS
1489  *
1490  * Internal function used to implement le_mem_CreateSubPool() with automatic component scoping
1491  * of pool names.
1492  */
1493 //--------------------------------------------------------------------------------------------------
1494 le_mem_PoolRef_t _le_mem_CreateReducedPool
1495 (
1496  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1497  size_t numObjects, ///< [IN] Minimum number of objects in the subpool
1498  ///< by default.
1499  size_t objSize ///< [IN] Minimum size of objects in the subpool.
1500 );
1501 /// @endcond
1502 //--------------------------------------------------------------------------------------------------
1503 /**
1504  * Creates a sub-pool of smaller objects.
1505  *
1506  * See @ref mem_reduced_pools for more information.
1507  *
1508  * @return
1509  * Reference to the sub-pool.
1510  */
1511 //--------------------------------------------------------------------------------------------------
1513 (
1514  le_mem_PoolRef_t superPool, ///< [IN] Super-pool.
1515  const char* name, ///< [IN] Name of the sub-pool (will be copied into the
1516  /// sub-pool).
1517  size_t numObjects, ///< [IN] Minimum number of objects in the subpool
1518  ///< by default.
1519  size_t objSize ///< [IN] Minimum size of objects in the subpool.
1520 )
1521 {
1522  return _le_mem_CreateReducedPool(superPool, numObjects, objSize);
1523 }
1524 #endif /* end LE_CONFIG_MEM_POOL_NAMES_ENABLED */
1525 
1526 
1527 //--------------------------------------------------------------------------------------------------
1528 /**
1529  * Deletes a sub-pool.
1530  *
1531  * See @ref mem_sub_pools for more information.
1532  *
1533  * @return
1534  * Nothing.
1535  */
1536 //--------------------------------------------------------------------------------------------------
1538 (
1539  le_mem_PoolRef_t subPool ///< [IN] Sub-pool to be deleted.
1540 );
1541 
1542 #if LE_CONFIG_RTOS
1543 //--------------------------------------------------------------------------------------------------
1544 /**
1545  * Compress memory pools ready for hibernate-to-RAM
1546  *
1547  * This compresses the memory pools ready for hibernation. All Legato tasks must remain
1548  * suspended until after le_mem_Resume() is called.
1549  *
1550  * @return Nothing
1551  */
1552 //--------------------------------------------------------------------------------------------------
1553 void le_mem_Hibernate
1554 (
1555  void **freeStartPtr, ///< [OUT] Beginning of unused memory which does not need to be
1556  ///< preserved in hibernation
1557  void **freeEndPtr ///< [OUT] End of unused memory
1558 );
1559 
1560 //--------------------------------------------------------------------------------------------------
1561 /**
1562  * Decompress memory pools after waking from hibernate-to-RAM
1563  *
1564  * This decompresses memory pools after hibernation. After this function returns, Legato tasks
1565  * may be resumed.
1566  *
1567  * @return Nothing
1568  */
1569 //--------------------------------------------------------------------------------------------------
1570 void le_mem_Resume
1571 (
1572  void
1573 );
1574 
1575 #endif /* end LE_CONFIG_RTOS */
1576 
1577 //--------------------------------------------------------------------------------------------------
1578 /**
1579  * Duplicate a UTF-8 string. The space for the duplicate string will be allocated from the provided
1580  * memory pool using le_mem_VarAlloc().
1581  *
1582  * @return The allocated duplicate of the string. This may later be released with
1583  * le_mem_Release().
1584  */
1585 //--------------------------------------------------------------------------------------------------
1586 char *le_mem_StrDup
1587 (
1588  le_mem_PoolRef_t poolRef, ///< Pool from which to allocate the string.
1589  const char *srcStr ///< String to duplicate.
1590 );
1591 
1592 #endif // LEGATO_MEM_INCLUDE_GUARD
size_t numBlocksToForce
Definition: le_mem.h:519
size_t numFree
Number of free objects currently available in this pool.
Definition: le_mem.h:554
uint64_t numAllocations
Definition: le_mem.h:506
void * le_mem_TryAlloc(le_mem_PoolRef_t pool)
le_sls_List_t freeList
List of free memory blocks.
Definition: le_mem.h:511
void * le_mem_TryVarAlloc(le_mem_PoolRef_t pool, size_t size)
le_mem_PoolRef_t le_mem_ExpandPool(le_mem_PoolRef_t pool, size_t numObjects)
le_result_t
Definition: le_basics.h:35
void * le_mem_AssertAlloc(le_mem_PoolRef_t pool)
void le_mem_GetStats(le_mem_PoolRef_t pool, le_mem_PoolStats_t *statsPtr)
void le_mem_Resume(void)
size_t numBlocksInUse
Number of currently allocated blocks.
Definition: le_mem.h:550
size_t totalBlocks
Definition: le_mem.h:516
struct le_mem_Pool * superPoolPtr
Definition: le_mem.h:500
#define STRINGIZE(x)
Definition: le_basics.h:207
void le_mem_SetDestructor(le_mem_PoolRef_t pool, le_mem_Destructor_t destructor)
void * le_mem_AssertVarAlloc(le_mem_PoolRef_t pool, size_t size)
uint64_t numAllocs
Number of times an object has been allocated from this pool.
Definition: le_mem.h:553
size_t maxNumBlocksUsed
Maximum number of allocated blocks at any one time.
Definition: le_mem.h:508
size_t maxNumBlocksUsed
Maximum number of allocated blocks at any one time.
Definition: le_mem.h:551
void * le_mem_ForceVarAlloc(le_mem_PoolRef_t pool, size_t size)
void le_mem_ResetStats(le_mem_PoolRef_t pool)
size_t numOverflows
Number of times le_mem_ForceAlloc() had to expand the pool.
Definition: le_mem.h:552
static le_mem_PoolRef_t le_mem_CreateReducedPool(le_mem_PoolRef_t superPool, const char *name, size_t numObjects, size_t objSize)
Definition: le_mem.h:1475
void le_mem_SetNumObjsToForce(le_mem_PoolRef_t pool, size_t numObjects)
size_t numOverflows
Number of times le_mem_ForceAlloc() had to expand pool.
Definition: le_mem.h:505
char * le_mem_StrDup(le_mem_PoolRef_t poolRef, const char *srcStr)
void le_mem_DeleteSubPool(le_mem_PoolRef_t subPool)
struct le_mem_Pool * le_mem_PoolRef_t
Definition: le_mem.h:540
le_result_t le_mem_GetName(le_mem_PoolRef_t pool, char *namePtr, size_t bufSize)
bool le_mem_IsSubPool(le_mem_PoolRef_t pool)
void le_mem_Release(void *objPtr)
Definition: le_mem.h:548
static le_mem_PoolRef_t le_mem_FindPool(const char *name)
Definition: le_mem.h:1347
size_t blockSize
Number of bytes in a block, including all overhead.
Definition: le_mem.h:515
void(* le_mem_Destructor_t)(void *objPtr)
Definition: le_mem.h:482
size_t le_mem_GetObjectCount(le_mem_PoolRef_t pool)
Definition: le_mem.h:497
Definition: le_singlyLinkedList.h:201
size_t le_mem_GetObjectFullSize(le_mem_PoolRef_t pool)
le_mem_Destructor_t destructor
The destructor for objects in this pool.
Definition: le_mem.h:526
size_t le_mem_GetBlockSize(void *objPtr)
static le_mem_PoolRef_t le_mem_CreatePool(const char *name, size_t objSize)
Definition: le_mem.h:672
size_t le_mem_GetObjectSize(le_mem_PoolRef_t pool)
le_dls_Link_t poolLink
This pool&#39;s link in the list of memory pools.
Definition: le_mem.h:499
static le_mem_PoolRef_t le_mem_CreateSubPool(le_mem_PoolRef_t superPool, const char *name, size_t numObjects)
Definition: le_mem.h:1400
void le_mem_AddRef(void *objPtr)
void * le_mem_ForceAlloc(le_mem_PoolRef_t pool)
size_t userDataSize
Size of the object requested by the client in bytes.
Definition: le_mem.h:514
void le_mem_Hibernate(void **freeStartPtr, void **freeEndPtr)
size_t numBlocksInUse
Number of currently allocated blocks.
Definition: le_mem.h:518
size_t le_mem_GetRefCount(void *objPtr)
#define LE_DECLARE_INLINE
Definition: le_basics.h:306