diff options
Diffstat (limited to 'kernel/gcov/gcc_4_7.c')
| -rw-r--r-- | kernel/gcov/gcc_4_7.c | 560 | 
1 files changed, 560 insertions, 0 deletions
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c new file mode 100644 index 000000000000..2c6e4631c814 --- /dev/null +++ b/kernel/gcov/gcc_4_7.c @@ -0,0 +1,560 @@ +/* + *  This code provides functions to handle gcc's profiling data format + *  introduced with gcc 4.7. + * + *  This file is based heavily on gcc_3_4.c file. + * + *  For a better understanding, refer to gcc source: + *  gcc/gcov-io.h + *  libgcc/libgcov.c + * + *  Uses gcc-internal data definitions. + */ + +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/seq_file.h> +#include <linux/vmalloc.h> +#include "gcov.h" + +#define GCOV_COUNTERS			8 +#define GCOV_TAG_FUNCTION_LENGTH	3 + +static struct gcov_info *gcov_info_head; + +/** + * struct gcov_ctr_info - information about counters for a single function + * @num: number of counter values for this type + * @values: array of counter values for this type + * + * This data is generated by gcc during compilation and doesn't change + * at run-time with the exception of the values array. + */ +struct gcov_ctr_info { +	unsigned int num; +	gcov_type *values; +}; + +/** + * struct gcov_fn_info - profiling meta data per function + * @key: comdat key + * @ident: unique ident of function + * @lineno_checksum: function lineo_checksum + * @cfg_checksum: function cfg checksum + * @ctrs: instrumented counters + * + * This data is generated by gcc during compilation and doesn't change + * at run-time. + * + * Information about a single function.  This uses the trailing array + * idiom. The number of counters is determined from the merge pointer + * array in gcov_info.  The key is used to detect which of a set of + * comdat functions was selected -- it points to the gcov_info object + * of the object file containing the selected comdat function. + */ +struct gcov_fn_info { +	const struct gcov_info *key; +	unsigned int ident; +	unsigned int lineno_checksum; +	unsigned int cfg_checksum; +	struct gcov_ctr_info ctrs[0]; +}; + +/** + * struct gcov_info - profiling data per object file + * @version: gcov version magic indicating the gcc version used for compilation + * @next: list head for a singly-linked list + * @stamp: uniquifying time stamp + * @filename: name of the associated gcov data file + * @merge: merge functions (null for unused counter type) + * @n_functions: number of instrumented functions + * @functions: pointer to pointers to function information + * + * This data is generated by gcc during compilation and doesn't change + * at run-time with the exception of the next pointer. + */ +struct gcov_info { +	unsigned int version; +	struct gcov_info *next; +	unsigned int stamp; +	const char *filename; +	void (*merge[GCOV_COUNTERS])(gcov_type *, unsigned int); +	unsigned int n_functions; +	struct gcov_fn_info **functions; +}; + +/** + * gcov_info_filename - return info filename + * @info: profiling data set + */ +const char *gcov_info_filename(struct gcov_info *info) +{ +	return info->filename; +} + +/** + * gcov_info_version - return info version + * @info: profiling data set + */ +unsigned int gcov_info_version(struct gcov_info *info) +{ +	return info->version; +} + +/** + * gcov_info_next - return next profiling data set + * @info: profiling data set + * + * Returns next gcov_info following @info or first gcov_info in the chain if + * @info is %NULL. + */ +struct gcov_info *gcov_info_next(struct gcov_info *info) +{ +	if (!info) +		return gcov_info_head; + +	return info->next; +} + +/** + * gcov_info_link - link/add profiling data set to the list + * @info: profiling data set + */ +void gcov_info_link(struct gcov_info *info) +{ +	info->next = gcov_info_head; +	gcov_info_head = info; +} + +/** + * gcov_info_unlink - unlink/remove profiling data set from the list + * @prev: previous profiling data set + * @info: profiling data set + */ +void gcov_info_unlink(struct gcov_info *prev, struct gcov_info *info) +{ +	if (prev) +		prev->next = info->next; +	else +		gcov_info_head = info->next; +} + +/* Symbolic links to be created for each profiling data file. */ +const struct gcov_link gcov_link[] = { +	{ OBJ_TREE, "gcno" },	/* Link to .gcno file in $(objtree). */ +	{ 0, NULL}, +}; + +/* + * Determine whether a counter is active. Doesn't change at run-time. + */ +static int counter_active(struct gcov_info *info, unsigned int type) +{ +	return info->merge[type] ? 1 : 0; +} + +/* Determine number of active counters. Based on gcc magic. */ +static unsigned int num_counter_active(struct gcov_info *info) +{ +	unsigned int i; +	unsigned int result = 0; + +	for (i = 0; i < GCOV_COUNTERS; i++) { +		if (counter_active(info, i)) +			result++; +	} +	return result; +} + +/** + * gcov_info_reset - reset profiling data to zero + * @info: profiling data set + */ +void gcov_info_reset(struct gcov_info *info) +{ +	struct gcov_ctr_info *ci_ptr; +	unsigned int fi_idx; +	unsigned int ct_idx; + +	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) { +		ci_ptr = info->functions[fi_idx]->ctrs; + +		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) { +			if (!counter_active(info, ct_idx)) +				continue; + +			memset(ci_ptr->values, 0, +					sizeof(gcov_type) * ci_ptr->num); +			ci_ptr++; +		} +	} +} + +/** + * gcov_info_is_compatible - check if profiling data can be added + * @info1: first profiling data set + * @info2: second profiling data set + * + * Returns non-zero if profiling data can be added, zero otherwise. + */ +int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2) +{ +	return (info1->stamp == info2->stamp); +} + +/** + * gcov_info_add - add up profiling data + * @dest: profiling data set to which data is added + * @source: profiling data set which is added + * + * Adds profiling counts of @source to @dest. + */ +void gcov_info_add(struct gcov_info *dst, struct gcov_info *src) +{ +	struct gcov_ctr_info *dci_ptr; +	struct gcov_ctr_info *sci_ptr; +	unsigned int fi_idx; +	unsigned int ct_idx; +	unsigned int val_idx; + +	for (fi_idx = 0; fi_idx < src->n_functions; fi_idx++) { +		dci_ptr = dst->functions[fi_idx]->ctrs; +		sci_ptr = src->functions[fi_idx]->ctrs; + +		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) { +			if (!counter_active(src, ct_idx)) +				continue; + +			for (val_idx = 0; val_idx < sci_ptr->num; val_idx++) +				dci_ptr->values[val_idx] += +					sci_ptr->values[val_idx]; + +			dci_ptr++; +			sci_ptr++; +		} +	} +} + +/** + * gcov_info_dup - duplicate profiling data set + * @info: profiling data set to duplicate + * + * Return newly allocated duplicate on success, %NULL on error. + */ +struct gcov_info *gcov_info_dup(struct gcov_info *info) +{ +	struct gcov_info *dup; +	struct gcov_ctr_info *dci_ptr; /* dst counter info */ +	struct gcov_ctr_info *sci_ptr; /* src counter info */ +	unsigned int active; +	unsigned int fi_idx; /* function info idx */ +	unsigned int ct_idx; /* counter type idx */ +	size_t fi_size; /* function info size */ +	size_t cv_size; /* counter values size */ + +	dup = kmemdup(info, sizeof(*dup), GFP_KERNEL); +	if (!dup) +		return NULL; + +	dup->next = NULL; +	dup->filename = NULL; +	dup->functions = NULL; + +	dup->filename = kstrdup(info->filename, GFP_KERNEL); +	if (!dup->filename) +		goto err_free; + +	dup->functions = kcalloc(info->n_functions, +				 sizeof(struct gcov_fn_info *), GFP_KERNEL); +	if (!dup->functions) +		goto err_free; + +	active = num_counter_active(info); +	fi_size = sizeof(struct gcov_fn_info); +	fi_size += sizeof(struct gcov_ctr_info) * active; + +	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) { +		dup->functions[fi_idx] = kzalloc(fi_size, GFP_KERNEL); +		if (!dup->functions[fi_idx]) +			goto err_free; + +		*(dup->functions[fi_idx]) = *(info->functions[fi_idx]); + +		sci_ptr = info->functions[fi_idx]->ctrs; +		dci_ptr = dup->functions[fi_idx]->ctrs; + +		for (ct_idx = 0; ct_idx < active; ct_idx++) { + +			cv_size = sizeof(gcov_type) * sci_ptr->num; + +			dci_ptr->values = vmalloc(cv_size); + +			if (!dci_ptr->values) +				goto err_free; + +			dci_ptr->num = sci_ptr->num; +			memcpy(dci_ptr->values, sci_ptr->values, cv_size); + +			sci_ptr++; +			dci_ptr++; +		} +	} + +	return dup; +err_free: +	gcov_info_free(dup); +	return NULL; +} + +/** + * gcov_info_free - release memory for profiling data set duplicate + * @info: profiling data set duplicate to free + */ +void gcov_info_free(struct gcov_info *info) +{ +	unsigned int active; +	unsigned int fi_idx; +	unsigned int ct_idx; +	struct gcov_ctr_info *ci_ptr; + +	if (!info->functions) +		goto free_info; + +	active = num_counter_active(info); + +	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) { +		if (!info->functions[fi_idx]) +			continue; + +		ci_ptr = info->functions[fi_idx]->ctrs; + +		for (ct_idx = 0; ct_idx < active; ct_idx++, ci_ptr++) +			vfree(ci_ptr->values); + +		kfree(info->functions[fi_idx]); +	} + +free_info: +	kfree(info->functions); +	kfree(info->filename); +	kfree(info); +} + +#define ITER_STRIDE	PAGE_SIZE + +/** + * struct gcov_iterator - specifies current file position in logical records + * @info: associated profiling data + * @buffer: buffer containing file data + * @size: size of buffer + * @pos: current position in file + */ +struct gcov_iterator { +	struct gcov_info *info; +	void *buffer; +	size_t size; +	loff_t pos; +}; + +/** + * store_gcov_u32 - store 32 bit number in gcov format to buffer + * @buffer: target buffer or NULL + * @off: offset into the buffer + * @v: value to be stored + * + * Number format defined by gcc: numbers are recorded in the 32 bit + * unsigned binary form of the endianness of the machine generating the + * file. Returns the number of bytes stored. If @buffer is %NULL, doesn't + * store anything. + */ +static size_t store_gcov_u32(void *buffer, size_t off, u32 v) +{ +	u32 *data; + +	if (buffer) { +		data = buffer + off; +		*data = v; +	} + +	return sizeof(*data); +} + +/** + * store_gcov_u64 - store 64 bit number in gcov format to buffer + * @buffer: target buffer or NULL + * @off: offset into the buffer + * @v: value to be stored + * + * Number format defined by gcc: numbers are recorded in the 32 bit + * unsigned binary form of the endianness of the machine generating the + * file. 64 bit numbers are stored as two 32 bit numbers, the low part + * first. Returns the number of bytes stored. If @buffer is %NULL, doesn't store + * anything. + */ +static size_t store_gcov_u64(void *buffer, size_t off, u64 v) +{ +	u32 *data; + +	if (buffer) { +		data = buffer + off; + +		data[0] = (v & 0xffffffffUL); +		data[1] = (v >> 32); +	} + +	return sizeof(*data) * 2; +} + +/** + * convert_to_gcda - convert profiling data set to gcda file format + * @buffer: the buffer to store file data or %NULL if no data should be stored + * @info: profiling data set to be converted + * + * Returns the number of bytes that were/would have been stored into the buffer. + */ +static size_t convert_to_gcda(char *buffer, struct gcov_info *info) +{ +	struct gcov_fn_info *fi_ptr; +	struct gcov_ctr_info *ci_ptr; +	unsigned int fi_idx; +	unsigned int ct_idx; +	unsigned int cv_idx; +	size_t pos = 0; + +	/* File header. */ +	pos += store_gcov_u32(buffer, pos, GCOV_DATA_MAGIC); +	pos += store_gcov_u32(buffer, pos, info->version); +	pos += store_gcov_u32(buffer, pos, info->stamp); + +	for (fi_idx = 0; fi_idx < info->n_functions; fi_idx++) { +		fi_ptr = info->functions[fi_idx]; + +		/* Function record. */ +		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION); +		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION_LENGTH); +		pos += store_gcov_u32(buffer, pos, fi_ptr->ident); +		pos += store_gcov_u32(buffer, pos, fi_ptr->lineno_checksum); +		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum); + +		ci_ptr = fi_ptr->ctrs; + +		for (ct_idx = 0; ct_idx < GCOV_COUNTERS; ct_idx++) { +			if (!counter_active(info, ct_idx)) +				continue; + +			/* Counter record. */ +			pos += store_gcov_u32(buffer, pos, +					      GCOV_TAG_FOR_COUNTER(ct_idx)); +			pos += store_gcov_u32(buffer, pos, ci_ptr->num * 2); + +			for (cv_idx = 0; cv_idx < ci_ptr->num; cv_idx++) { +				pos += store_gcov_u64(buffer, pos, +						      ci_ptr->values[cv_idx]); +			} + +			ci_ptr++; +		} +	} + +	return pos; +} + +/** + * gcov_iter_new - allocate and initialize profiling data iterator + * @info: profiling data set to be iterated + * + * Return file iterator on success, %NULL otherwise. + */ +struct gcov_iterator *gcov_iter_new(struct gcov_info *info) +{ +	struct gcov_iterator *iter; + +	iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL); +	if (!iter) +		goto err_free; + +	iter->info = info; +	/* Dry-run to get the actual buffer size. */ +	iter->size = convert_to_gcda(NULL, info); +	iter->buffer = vmalloc(iter->size); +	if (!iter->buffer) +		goto err_free; + +	convert_to_gcda(iter->buffer, info); + +	return iter; + +err_free: +	kfree(iter); +	return NULL; +} + + +/** + * gcov_iter_get_info - return profiling data set for given file iterator + * @iter: file iterator + */ +void gcov_iter_free(struct gcov_iterator *iter) +{ +	vfree(iter->buffer); +	kfree(iter); +} + +/** + * gcov_iter_get_info - return profiling data set for given file iterator + * @iter: file iterator + */ +struct gcov_info *gcov_iter_get_info(struct gcov_iterator *iter) +{ +	return iter->info; +} + +/** + * gcov_iter_start - reset file iterator to starting position + * @iter: file iterator + */ +void gcov_iter_start(struct gcov_iterator *iter) +{ +	iter->pos = 0; +} + +/** + * gcov_iter_next - advance file iterator to next logical record + * @iter: file iterator + * + * Return zero if new position is valid, non-zero if iterator has reached end. + */ +int gcov_iter_next(struct gcov_iterator *iter) +{ +	if (iter->pos < iter->size) +		iter->pos += ITER_STRIDE; + +	if (iter->pos >= iter->size) +		return -EINVAL; + +	return 0; +} + +/** + * gcov_iter_write - write data for current pos to seq_file + * @iter: file iterator + * @seq: seq_file handle + * + * Return zero on success, non-zero otherwise. + */ +int gcov_iter_write(struct gcov_iterator *iter, struct seq_file *seq) +{ +	size_t len; + +	if (iter->pos >= iter->size) +		return -EINVAL; + +	len = ITER_STRIDE; +	if (iter->pos + len > iter->size) +		len = iter->size - iter->pos; + +	seq_write(seq, iter->buffer + iter->pos, len); + +	return 0; +}  | 
