[apple/libc.git] / gen / stack_logging.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

/*	Bertrand from vmutils -> CF -> System */

#import "stack_logging.h"
#import "malloc_printf.h"

#import <libc.h>
#import <pthread.h>
#import <mach/mach.h>
#include <mach/vm_statistics.h>
#import <malloc/malloc.h>
#import <stdlib.h>

extern void spin_lock(int *);
extern void spin_unlock(int *);
extern void thread_stack_pcs(vm_address_t *, unsigned, unsigned *);

static inline void *allocate_pages(unsigned) __attribute__((always_inline));
static inline void *allocate_pages(unsigned bytes) {
    void *address;
    if (vm_allocate(mach_task_self(), (vm_address_t *)&address, bytes, 
                    VM_MAKE_TAG(VM_MEMORY_ANALYSIS_TOOL)| TRUE)) {
	malloc_printf("*** out of memory while stack logging\n");
	abort();
    } 
    return (void *)address;
}

static inline void deallocate_pages(void *, unsigned) __attribute__((always_inline));
static inline void deallocate_pages(void *ptr, unsigned bytes) {
    vm_deallocate(mach_task_self(), (vm_address_t)ptr, bytes);
}

static inline void copy_pages(const void *, void *, unsigned) __attribute__((always_inline));
static inline void copy_pages(const void *source, void *dest, unsigned bytes) {
    if (vm_copy(mach_task_self(), (vm_address_t)source, bytes, (vm_address_t)dest)) memmove(dest, source, bytes);
}

/***************	Uniquing stack		***********/

#define MAX_COLLIDE	8

#define MAX_NUM_PC	512

static int enter_pair_in_table(unsigned *table, unsigned numPages, unsigned *uniquedParent, unsigned thisPC) {
    // uniquedParent is in-out; return 1 is collisions max not exceeded
    unsigned	base = numPages * vm_page_size / (sizeof(int)*2*2);
    unsigned	hash = base + (((*uniquedParent) << 4) ^ (thisPC >> 2)) % (base - 1); // modulo odd number for hashing
    unsigned	collisions = MAX_COLLIDE;
    while (collisions--) {
        unsigned	*head = table + hash*2;
        if (! head[0] && !head[1]) {
            /* end of chain; store this entry! */
            /* Note that we need to test for both head[0] and head[1] as (0, -1) is a valid entry */
            head[0] = thisPC;
            head[1] = *uniquedParent;
            *uniquedParent = hash;
            return 1;
        }
        if ((head[0] == thisPC) && (head[1] == *uniquedParent)) {
            /* we found the proper entry, the value for the pair is the entry offset */
            *uniquedParent = hash;
            return 1;
        }
        hash++;
        if (hash == base*2) hash = base;
    }
    return 0;
}

unsigned stack_logging_get_unique_stack(unsigned **table, unsigned *table_num_pages, unsigned *stack_entries, unsigned count, unsigned num_hot_to_skip) {
    unsigned	uniquedParent = (unsigned)-1;
    // we skip the warmest entries that are an artefact of the code
    while (num_hot_to_skip--) {
        if (count > 0) { stack_entries++; count--; }
    }
    while (count--) {
        unsigned	thisPC = stack_entries[count];
        while (!enter_pair_in_table(*table, *table_num_pages, &uniquedParent, thisPC)) {
            unsigned	*newTable;
            unsigned	oldBytes = (*table_num_pages) * vm_page_size;
            newTable = allocate_pages(oldBytes*2);
            copy_pages(*table, newTable, oldBytes);
            deallocate_pages(*table, oldBytes);
            *table_num_pages *= 2;
            *table = newTable;
        }
    }
    return uniquedParent;
}

/***************	Logging stack and arguments		***********/

stack_logging_record_list_t *stack_logging_the_record_list = NULL;

int stack_logging_enable_logging = 0;

int stack_logging_dontcompact = 0;

static int stack_logging_spin_lock = 0;

static stack_logging_record_list_t *GrowLogRecords(stack_logging_record_list_t *records, unsigned desiredNumRecords) {
    stack_logging_record_list_t	*new_records;
    unsigned	old_size = records->overall_num_bytes;
    if (desiredNumRecords*sizeof(stack_logging_record_t)+sizeof(stack_logging_record_list_t) < records->overall_num_bytes) return records;
    records->overall_num_bytes += records->overall_num_bytes + vm_page_size; // in order to always get an even number of pages
    new_records = allocate_pages(records->overall_num_bytes);
    copy_pages(records, new_records, old_size);
    deallocate_pages(records, old_size);
    return new_records;
}

static void prepare_to_log_stack(void) {
    if (!stack_logging_the_record_list) {
        unsigned	totalSize = 4 * vm_page_size;
        stack_logging_the_record_list = allocate_pages(totalSize);
        memset(stack_logging_the_record_list, 0, sizeof(stack_logging_record_list_t));
        stack_logging_the_record_list->overall_num_bytes = totalSize;
        stack_logging_the_record_list->uniquing_table_num_pages = 128;
        stack_logging_the_record_list->uniquing_table = allocate_pages(stack_logging_the_record_list->uniquing_table_num_pages * vm_page_size);
    }
}

void stack_logging_log_stack(unsigned type, unsigned arg1, unsigned arg2, unsigned arg3, unsigned result, unsigned num_hot_to_skip) {
    stack_logging_record_t	*rec;
    if (!stack_logging_enable_logging) return;
    // printf("stack_logging_log_stack 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
    if (type & stack_logging_flag_zone) {
        // just process it now and be done with it!
        arg1 = arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_zone;
    }
    if (type & stack_logging_flag_calloc) {
        // just process it now and be done with it!
        arg1 *= arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_calloc;
    }
    if (type & stack_logging_flag_object) {
        unsigned	*class = (unsigned *)arg1;
        arg1 = arg2 + class[5]; // corresponds to the instance_size field
        arg2 = 0; arg3 = 0; type = stack_logging_type_alloc;
    }
    if (type & stack_logging_flag_cleared) {
        type &= ~stack_logging_flag_cleared;
    }
    if (type & stack_logging_flag_handle) {
        if (stack_logging_type_alloc) {
            if (!result) return;
            stack_logging_log_stack(stack_logging_type_alloc, 0, 0, 0, result, num_hot_to_skip+1);
            stack_logging_log_stack(stack_logging_type_alloc, arg1, 0, 0, *((int *)result), num_hot_to_skip+1);
            return;
        }
        if (stack_logging_type_dealloc) {
            if (!arg1) return;
            stack_logging_log_stack(stack_logging_type_dealloc, *((int *)arg1), 0, 0, 0, num_hot_to_skip+1);
            stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
            return;
        }
        fprintf(stderr, "*** Unknown logging type: 0x%x\n", type);
    }
    if (type == stack_logging_flag_set_handle_size) {
        if (!arg1) return;
        // Thanks to a horrible hack, arg3 contains the prvious handle value
        if (arg3 == *((int *)arg1)) return;
        stack_logging_log_stack(stack_logging_type_dealloc, arg3, 0, 0, 0, num_hot_to_skip+1);
        stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, *((int *)arg1), num_hot_to_skip+1);
        return;
    }            
    if (type == (stack_logging_type_dealloc|stack_logging_type_alloc)) {
        if (arg1 == result) return; // realloc had no effect, skipping
        if (!arg1) {
            // realloc(NULL, size) same as malloc(size)
            type = stack_logging_type_alloc; arg1 = arg2; arg2 = arg3; arg3 = 0;
	} else {
            // realloc(arg1, arg2) -> result is same as free(arg1); malloc(arg2) -> result
            stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
            stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, result, num_hot_to_skip+1);
            return;
        }
    }
    if (type == stack_logging_type_dealloc) {
        // simple free
        if (!arg1) return; // free(nil)
    }
    prepare_to_log_stack();
    spin_lock(&stack_logging_spin_lock);
    stack_logging_the_record_list = GrowLogRecords(stack_logging_the_record_list, stack_logging_the_record_list->num_records + 1);
    rec = stack_logging_the_record_list->records + stack_logging_the_record_list->num_records;
    // We take care of the common case of alloc-dealloc
    if (!stack_logging_dontcompact && stack_logging_the_record_list->num_records && (type == stack_logging_type_dealloc) && arg1 && ((rec-1)->type == stack_logging_type_alloc) && (arg1 == STACK_LOGGING_DISGUISE((rec-1)->address))) {
        stack_logging_the_record_list->num_records--;
        // printf("Erased previous record in alloc-dealloc sequence\n");
    } else {
        unsigned	stack_entries[MAX_NUM_PC];
        unsigned	count = 0;
        rec->type = type;
        if (type == stack_logging_type_dealloc) {
            rec->argument = 0;
            rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
        } else if (type == stack_logging_type_alloc) {
            rec->argument = arg1;
            rec->address = STACK_LOGGING_DISGUISE(result); // we disguise the address
        } else {
            rec->argument = arg2;
            rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
        }
	// printf("Before getting samples  0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
        thread_stack_pcs(stack_entries, MAX_NUM_PC - 1, &count);
        // We put at the bottom of the stack a marker that denotes the thread (+1 for good measure...)
        stack_entries[count++] = (int)pthread_self() + 1;
        /* now let's unique the sample */    
        // printf("Uniquing 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
        rec->uniqued_stack = stack_logging_get_unique_stack(&stack_logging_the_record_list->uniquing_table, &stack_logging_the_record_list->uniquing_table_num_pages, stack_entries, count, num_hot_to_skip+2); // we additionally skip the warmest 2 entries that are an artefact of the code
        stack_logging_the_record_list->num_records++;
    }
    spin_unlock(&stack_logging_spin_lock);
}

static kern_return_t default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr) {
    *ptr = (void *)address;
    return 0;
}

static kern_return_t get_remote_records(task_t task, memory_reader_t reader, stack_logging_record_list_t **records) {
    // sets records
    vm_address_t	*remote_records_address_ref;
    kern_return_t	err;
    *records = NULL;
    err = reader(task, (vm_address_t)&stack_logging_the_record_list, sizeof(vm_address_t), (void **)&remote_records_address_ref);
    if (err) return err;
    if (!*remote_records_address_ref) {
        // printf("stack_logging: no stack record\n");
        return 0;
    }
    // printf("stack_logging: stack records at %p\n", (void *)(*remote_records_address_ref));
    // printf("stack_logging: reading %d bytes\n", sizeof(stack_logging_record_list_t));
    err = reader(task, *remote_records_address_ref, sizeof(stack_logging_record_list_t), (void **)records); // get the list head
    if (err) return err;
    // printf("stack_logging: overall num bytes = %d\n", records->overall_num_bytes);
    return reader(task, *remote_records_address_ref, (*records)->overall_num_bytes, (void **)records);
}

kern_return_t stack_logging_get_frames(task_t task, memory_reader_t reader, vm_address_t address, vm_address_t *stack_frames_buffer, unsigned max_stack_frames, unsigned *num_frames) {
    stack_logging_record_list_t	*records;
    kern_return_t	err;
    unsigned		index;
    unsigned		disguised = STACK_LOGGING_DISGUISE(address);
    if (!reader) reader = default_reader;
    *num_frames = 0;
    err = get_remote_records(task, reader, &records);
    if (err || !records) return err;
    // printf("stack_logging: %d records\n", records->num_records);
    index = 0;
    while (index < records->num_records) {
        stack_logging_record_t	*record = records->records + index;
        if (record->address == disguised) {
	    return stack_logging_frames_for_uniqued_stack(task, reader, record->uniqued_stack, stack_frames_buffer, max_stack_frames, num_frames);
        }
	index++;
    }
    fprintf(stderr, "*** stack_logging: no record found for 0x%x\n", address);
    return 0;
}

kern_return_t stack_logging_enumerate_records(task_t task, memory_reader_t reader, vm_address_t address, void enumerator(stack_logging_record_t, void *), void *context) {
    stack_logging_record_list_t	*records;
    kern_return_t	err;
    unsigned		index;
    unsigned		disguised = STACK_LOGGING_DISGUISE(address);
    if (!reader) reader = default_reader;
    err = get_remote_records(task, reader, &records);
    if (err || !records) return err;
    // printf("stack_logging: %d records\n", records->num_records);
    index = 0;
    while (index < records->num_records) {
        stack_logging_record_t	*record = records->records + index;
        if (!address || (record->address == disguised)) enumerator(*record, context);
	index++;
    }
    return 0;
}

kern_return_t stack_logging_frames_for_uniqued_stack(task_t task, memory_reader_t reader, unsigned uniqued_stack, vm_address_t *stack_frames_buffer, unsigned max_stack_frames, unsigned *num_frames) {
    stack_logging_record_list_t	*records;
    unsigned		*uniquing_table;
    kern_return_t	err;
    if (!reader) reader = default_reader;
    *num_frames = 0;
    err = get_remote_records(task, reader, &records);
    if (err || !records) return err;
    err = reader(task, (vm_address_t)records->uniquing_table, records->uniquing_table_num_pages * vm_page_size, (void **)&uniquing_table);
    if (err) return err;
    while (max_stack_frames && (uniqued_stack != -1)) {
	unsigned	thisPC;
	if ((uniqued_stack * 2 + 1) * sizeof(unsigned) >= records->uniquing_table_num_pages * vm_page_size) {
	    fprintf(stderr, "*** stack_logging: Invalid uniqued stack 0x%x", uniqued_stack);
	    break;
	}
	thisPC = uniquing_table[uniqued_stack * 2];
	uniqued_stack = uniquing_table[uniqued_stack * 2 + 1];
	if (!thisPC && !uniqued_stack) {
	    // Invalid entry
	    fprintf(stderr, "*** stack_logging: Invalid entry 0x%x", thisPC);
	    break;
	}
	stack_frames_buffer[0] = thisPC;
	stack_frames_buffer++;
	(*num_frames)++;
	max_stack_frames--;
    }
    return 0;
}
Commit	Line	Data
e9ce8d39 A	1	/*
	2	* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
734aad71 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
	12	*
	13	* The Original Code and all software distributed under the License are
	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
e9ce8d39 A	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
e9ce8d39 A	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
734aad71 A	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
e9ce8d39 A	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23
	24	/* Bertrand from vmutils -> CF -> System */
	25
	26	#import "stack_logging.h"
224c7076	27	#import "malloc_printf.h"
e9ce8d39 A	28
	29	#import <libc.h>
	30	#import <pthread.h>
	31	#import <mach/mach.h>
	32	#include <mach/vm_statistics.h>
9385eb3d A	33	#import <malloc/malloc.h>
9385eb3d A	34	#import <stdlib.h>
e9ce8d39 A	35
e9ce8d39 A	36	extern void spin_lock(int *);
224c7076 A	37	extern void spin_unlock(int *);
224c7076 A	38	extern void thread_stack_pcs(vm_address_t , unsigned, unsigned );
e9ce8d39	39
3d9156a7	40	static inline void *allocate_pages(unsigned) __attribute__((always_inline));
e9ce8d39 A	41	static inline void *allocate_pages(unsigned bytes) {
	42	void *address;
	43	if (vm_allocate(mach_task_self(), (vm_address_t *)&address, bytes,
	44	VM_MAKE_TAG(VM_MEMORY_ANALYSIS_TOOL)\| TRUE)) {
59e0d9fe	45	malloc_printf("*** out of memory while stack logging\n");
9385eb3d	46	abort();
e9ce8d39 A	47	}
	48	return (void *)address;
	49	}
	50
3d9156a7	51	static inline void deallocate_pages(void *, unsigned) __attribute__((always_inline));
e9ce8d39 A	52	static inline void deallocate_pages(void *ptr, unsigned bytes) {
	53	vm_deallocate(mach_task_self(), (vm_address_t)ptr, bytes);
	54	}
	55
3d9156a7	56	static inline void copy_pages(const void , void , unsigned) __attribute__((always_inline));
e9ce8d39 A	57	static inline void copy_pages(const void source, void dest, unsigned bytes) {
	58	if (vm_copy(mach_task_self(), (vm_address_t)source, bytes, (vm_address_t)dest)) memmove(dest, source, bytes);
	59	}
	60
e9ce8d39 A	61	/************* Uniquing stack *********/
	62
	63	#define MAX_COLLIDE 8
	64
	65	#define MAX_NUM_PC 512
	66
	67	static int enter_pair_in_table(unsigned table, unsigned numPages, unsigned uniquedParent, unsigned thisPC) {
	68	// uniquedParent is in-out; return 1 is collisions max not exceeded
	69	unsigned base = numPages * vm_page_size / (sizeof(int)22);
	70	unsigned hash = base + (((*uniquedParent) << 4) ^ (thisPC >> 2)) % (base - 1); // modulo odd number for hashing
	71	unsigned collisions = MAX_COLLIDE;
	72	while (collisions--) {
	73	unsigned head = table + hash2;
	74	if (! head[0] && !head[1]) {
	75	/* end of chain; store this entry! */
	76	/* Note that we need to test for both head[0] and head[1] as (0, -1) is a valid entry */
	77	head[0] = thisPC;
	78	head[1] = *uniquedParent;
	79	*uniquedParent = hash;
	80	return 1;
	81	}
	82	if ((head[0] == thisPC) && (head[1] == *uniquedParent)) {
	83	/* we found the proper entry, the value for the pair is the entry offset */
	84	*uniquedParent = hash;
	85	return 1;
	86	}
	87	hash++;
	88	if (hash == base*2) hash = base;
	89	}
	90	return 0;
	91	}
	92
	93	unsigned stack_logging_get_unique_stack(unsigned *table, unsigned table_num_pages, unsigned *stack_entries, unsigned count, unsigned num_hot_to_skip) {
	94	unsigned uniquedParent = (unsigned)-1;
	95	// we skip the warmest entries that are an artefact of the code
	96	while (num_hot_to_skip--) {
	97	if (count > 0) { stack_entries++; count--; }
	98	}
	99	while (count--) {
	100	unsigned thisPC = stack_entries[count];
	101	while (!enter_pair_in_table(table, table_num_pages, &uniquedParent, thisPC)) {
	102	unsigned *newTable;
	103	unsigned oldBytes = (table_num_pages) vm_page_size;
	104	newTable = allocate_pages(oldBytes*2);
	105	copy_pages(*table, newTable, oldBytes);
	106	deallocate_pages(*table, oldBytes);
	107	table_num_pages = 2;
	108	*table = newTable;
	109	}
	110	}
	111	return uniquedParent;
	112	}
	113
	114	/************* Logging stack and arguments *********/
	115
	116	stack_logging_record_list_t *stack_logging_the_record_list = NULL;
	117
	118	int stack_logging_enable_logging = 0;
	119
	120	int stack_logging_dontcompact = 0;
	121
224c7076 A	122	static int stack_logging_spin_lock = 0;
224c7076 A	123
e9ce8d39 A	124	static stack_logging_record_list_t GrowLogRecords(stack_logging_record_list_t records, unsigned desiredNumRecords) {
	125	stack_logging_record_list_t *new_records;
	126	unsigned old_size = records->overall_num_bytes;
	127	if (desiredNumRecords*sizeof(stack_logging_record_t)+sizeof(stack_logging_record_list_t) < records->overall_num_bytes) return records;
	128	records->overall_num_bytes += records->overall_num_bytes + vm_page_size; // in order to always get an even number of pages
	129	new_records = allocate_pages(records->overall_num_bytes);
	130	copy_pages(records, new_records, old_size);
	131	deallocate_pages(records, old_size);
	132	return new_records;
	133	}
	134
	135	static void prepare_to_log_stack(void) {
	136	if (!stack_logging_the_record_list) {
	137	unsigned totalSize = 4 * vm_page_size;
	138	stack_logging_the_record_list = allocate_pages(totalSize);
	139	memset(stack_logging_the_record_list, 0, sizeof(stack_logging_record_list_t));
	140	stack_logging_the_record_list->overall_num_bytes = totalSize;
	141	stack_logging_the_record_list->uniquing_table_num_pages = 128;
	142	stack_logging_the_record_list->uniquing_table = allocate_pages(stack_logging_the_record_list->uniquing_table_num_pages * vm_page_size);
	143	}
	144	}
	145
	146	void stack_logging_log_stack(unsigned type, unsigned arg1, unsigned arg2, unsigned arg3, unsigned result, unsigned num_hot_to_skip) {
	147	stack_logging_record_t *rec;
	148	if (!stack_logging_enable_logging) return;
	149	// printf("stack_logging_log_stack 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
	150	if (type & stack_logging_flag_zone) {
	151	// just process it now and be done with it!
	152	arg1 = arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_zone;
	153	}
	154	if (type & stack_logging_flag_calloc) {
	155	// just process it now and be done with it!
	156	arg1 *= arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_calloc;
	157	}
	158	if (type & stack_logging_flag_object) {
	159	unsigned class = (unsigned )arg1;
	160	arg1 = arg2 + class[5]; // corresponds to the instance_size field
	161	arg2 = 0; arg3 = 0; type = stack_logging_type_alloc;
	162	}
	163	if (type & stack_logging_flag_cleared) {
	164	type &= ~stack_logging_flag_cleared;
	165	}
	166	if (type & stack_logging_flag_handle) {
	167	if (stack_logging_type_alloc) {
	168	if (!result) return;
	169	stack_logging_log_stack(stack_logging_type_alloc, 0, 0, 0, result, num_hot_to_skip+1);
	170	stack_logging_log_stack(stack_logging_type_alloc, arg1, 0, 0, ((int )result), num_hot_to_skip+1);
	171	return;
	172	}
	173	if (stack_logging_type_dealloc) {
	174	if (!arg1) return;
	175	stack_logging_log_stack(stack_logging_type_dealloc, ((int )arg1), 0, 0, 0, num_hot_to_skip+1);
	176	stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
	177	return;
	178	}
224c7076	179	fprintf(stderr, "*** Unknown logging type: 0x%x\n", type);
e9ce8d39 A	180	}
	181	if (type == stack_logging_flag_set_handle_size) {
	182	if (!arg1) return;
	183	// Thanks to a horrible hack, arg3 contains the prvious handle value
	184	if (arg3 == ((int )arg1)) return;
	185	stack_logging_log_stack(stack_logging_type_dealloc, arg3, 0, 0, 0, num_hot_to_skip+1);
	186	stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, ((int )arg1), num_hot_to_skip+1);
	187	return;
	188	}
	189	if (type == (stack_logging_type_dealloc\|stack_logging_type_alloc)) {
	190	if (arg1 == result) return; // realloc had no effect, skipping
	191	if (!arg1) {
	192	// realloc(NULL, size) same as malloc(size)
	193	type = stack_logging_type_alloc; arg1 = arg2; arg2 = arg3; arg3 = 0;
	194	} else {
	195	// realloc(arg1, arg2) -> result is same as free(arg1); malloc(arg2) -> result
	196	stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
	197	stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, result, num_hot_to_skip+1);
	198	return;
	199	}
	200	}
	201	if (type == stack_logging_type_dealloc) {
	202	// simple free
	203	if (!arg1) return; // free(nil)
	204	}
	205	prepare_to_log_stack();
224c7076	206	spin_lock(&stack_logging_spin_lock);
e9ce8d39 A	207	stack_logging_the_record_list = GrowLogRecords(stack_logging_the_record_list, stack_logging_the_record_list->num_records + 1);
	208	rec = stack_logging_the_record_list->records + stack_logging_the_record_list->num_records;
	209	// We take care of the common case of alloc-dealloc
	210	if (!stack_logging_dontcompact && stack_logging_the_record_list->num_records && (type == stack_logging_type_dealloc) && arg1 && ((rec-1)->type == stack_logging_type_alloc) && (arg1 == STACK_LOGGING_DISGUISE((rec-1)->address))) {
	211	stack_logging_the_record_list->num_records--;
	212	// printf("Erased previous record in alloc-dealloc sequence\n");
	213	} else {
	214	unsigned stack_entries[MAX_NUM_PC];
	215	unsigned count = 0;
	216	rec->type = type;
	217	if (type == stack_logging_type_dealloc) {
	218	rec->argument = 0;
	219	rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
	220	} else if (type == stack_logging_type_alloc) {
	221	rec->argument = arg1;
	222	rec->address = STACK_LOGGING_DISGUISE(result); // we disguise the address
	223	} else {
	224	rec->argument = arg2;
	225	rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
	226	}
	227	// printf("Before getting samples 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
	228	thread_stack_pcs(stack_entries, MAX_NUM_PC - 1, &count);
	229	// We put at the bottom of the stack a marker that denotes the thread (+1 for good measure...)
	230	stack_entries[count++] = (int)pthread_self() + 1;
	231	/* now let's unique the sample */
	232	// printf("Uniquing 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
	233	rec->uniqued_stack = stack_logging_get_unique_stack(&stack_logging_the_record_list->uniquing_table, &stack_logging_the_record_list->uniquing_table_num_pages, stack_entries, count, num_hot_to_skip+2); // we additionally skip the warmest 2 entries that are an artefact of the code
	234	stack_logging_the_record_list->num_records++;
	235	}
224c7076	236	spin_unlock(&stack_logging_spin_lock);
e9ce8d39 A	237	}
	238
	239	static kern_return_t default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr) {
	240	ptr = (void )address;
	241	return 0;
	242	}
	243
	244	static kern_return_t get_remote_records(task_t task, memory_reader_t reader, stack_logging_record_list_t **records) {
	245	// sets records
	246	vm_address_t *remote_records_address_ref;
	247	kern_return_t err;
	248	*records = NULL;
	249	err = reader(task, (vm_address_t)&stack_logging_the_record_list, sizeof(vm_address_t), (void **)&remote_records_address_ref);
	250	if (err) return err;
	251	if (!*remote_records_address_ref) {
	252	// printf("stack_logging: no stack record\n");
	253	return 0;
	254	}
	255	// printf("stack_logging: stack records at %p\n", (void )(remote_records_address_ref));
	256	// printf("stack_logging: reading %d bytes\n", sizeof(stack_logging_record_list_t));
	257	err = reader(task, remote_records_address_ref, sizeof(stack_logging_record_list_t), (void *)records); // get the list head
	258	if (err) return err;
	259	// printf("stack_logging: overall num bytes = %d\n", records->overall_num_bytes);
	260	return reader(task, remote_records_address_ref, (records)->overall_num_bytes, (void **)records);
	261	}
	262
	263	kern_return_t stack_logging_get_frames(task_t task, memory_reader_t reader, vm_address_t address, vm_address_t stack_frames_buffer, unsigned max_stack_frames, unsigned num_frames) {
	264	stack_logging_record_list_t *records;
	265	kern_return_t err;
	266	unsigned index;
	267	unsigned disguised = STACK_LOGGING_DISGUISE(address);
	268	if (!reader) reader = default_reader;
	269	*num_frames = 0;
	270	err = get_remote_records(task, reader, &records);
	271	if (err \|\| !records) return err;
	272	// printf("stack_logging: %d records\n", records->num_records);
	273	index = 0;
	274	while (index < records->num_records) {
	275	stack_logging_record_t *record = records->records + index;
	276	if (record->address == disguised) {
	277	return stack_logging_frames_for_uniqued_stack(task, reader, record->uniqued_stack, stack_frames_buffer, max_stack_frames, num_frames);
	278	}
	279	index++;
	280	}
	281	fprintf(stderr, "*** stack_logging: no record found for 0x%x\n", address);
	282	return 0;
	283	}
	284
	285	kern_return_t stack_logging_enumerate_records(task_t task, memory_reader_t reader, vm_address_t address, void enumerator(stack_logging_record_t, void ), void context) {
	286	stack_logging_record_list_t *records;
	287	kern_return_t err;
	288	unsigned index;
	289	unsigned disguised = STACK_LOGGING_DISGUISE(address);
	290	if (!reader) reader = default_reader;
	291	err = get_remote_records(task, reader, &records);
	292	if (err \|\| !records) return err;
	293	// printf("stack_logging: %d records\n", records->num_records);
	294	index = 0;
	295	while (index < records->num_records) {
	296	stack_logging_record_t *record = records->records + index;
	297	if (!address \|\| (record->address == disguised)) enumerator(*record, context);
	298	index++;
	299	}
	300	return 0;
301	}
302
303	kern_return_t stack_logging_frames_for_uniqued_stack(task_t task, memory_reader_t reader, unsigned uniqued_stack, vm_address_t stack_frames_buffer, unsigned max_stack_frames, unsigned num_frames) {
304	stack_logging_record_list_t *records;
305	unsigned *uniquing_table;
306	kern_return_t err;
307	if (!reader) reader = default_reader;
308	*num_frames = 0;
309	err = get_remote_records(task, reader, &records);
310	if (err \|\| !records) return err;
311	err = reader(task, (vm_address_t)records->uniquing_table, records->uniquing_table_num_pages * vm_page_size, (void **)&uniquing_table);
312	if (err) return err;
313	while (max_stack_frames && (uniqued_stack != -1)) {
314	unsigned thisPC;
315	if ((uniqued_stack * 2 + 1) * sizeof(unsigned) >= records->uniquing_table_num_pages * vm_page_size) {
316	fprintf(stderr, "*** stack_logging: Invalid uniqued stack 0x%x", uniqued_stack);
317	break;
318	}
319	thisPC = uniquing_table[uniqued_stack * 2];
320	uniqued_stack = uniquing_table[uniqued_stack * 2 + 1];
321	if (!thisPC && !uniqued_stack) {
322	// Invalid entry
323	fprintf(stderr, "*** stack_logging: Invalid entry 0x%x", thisPC);
324	break;
325	}
326	stack_frames_buffer[0] = thisPC;
327	stack_frames_buffer++;
328	(*num_frames)++;
329	max_stack_frames--;
330	}
331	return 0;
332	}