Commit 9b472e85 authored by Nick Desaulniers's avatar Nick Desaulniers Committed by Linus Torvalds
Browse files

gcov: clang: drop support for clang-10 and older 

LLVM changed the expected function signatures for llvm_gcda_start_file()
and llvm_gcda_emit_function() in the clang-11 release.  Drop the older
implementations and require folks to upgrade their compiler if they're
interested in GCOV support.

Link: https://reviews.llvm.org/rGcdd683b516d147925212724b09ec6fb792a40041
Link: https://reviews.llvm.org/rG13a633b438b6500ecad9e4f936ebadf3411d0f44
Link: https://lkml.kernel.org/r/20210312224132.3413602-3-ndesaulniers@google.com
Link: https://lkml.kernel.org/r/20210413183113.2977432-1-ndesaulniers@google.com


Signed-off-by: default avatarNick Desaulniers <ndesaulniers@google.com>
Suggested-by: default avatarNathan Chancellor <nathan@kernel.org>
Acked-by: default avatarPeter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: default avatarNathan Chancellor <nathan@kernel.org>
Reviewed-by: default avatarFangrui Song <maskray@google.com>
Cc: Prasad Sodagudi <psodagud@quicinc.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 1391efa9

kernel/gcov/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ menu "GCOV-based kernel profiling" 
config GCOV_KERNEL

	bool "Enable gcov-based kernel profiling"

	depends on DEBUG_FS

	depends on !CC_IS_CLANG || CLANG_VERSION >= 110000

	select CONSTRUCTORS

	default n

	help

kernel/gcov/clang.c

+0 −103
Original line number Diff line number Diff line
@@ -69,16 +69,10 @@ struct gcov_fn_info { 


	u32 ident;

	u32 checksum;

#if CONFIG_CLANG_VERSION < 110000

	u8 use_extra_checksum;

#endif

	u32 cfg_checksum;



	u32 num_counters;

	u64 *counters;

#if CONFIG_CLANG_VERSION < 110000

	const char *function_name;

#endif

};



static struct gcov_info *current_info;
@@ -108,16 +102,6 @@ void llvm_gcov_init(llvm_gcov_callback writeout, llvm_gcov_callback flush) 
}

EXPORT_SYMBOL(llvm_gcov_init);



#if CONFIG_CLANG_VERSION < 110000

void llvm_gcda_start_file(const char *orig_filename, const char version[4],

		u32 checksum)

{

	current_info->filename = orig_filename;

	memcpy(&current_info->version, version, sizeof(current_info->version));

	current_info->checksum = checksum;

}

EXPORT_SYMBOL(llvm_gcda_start_file);

#else

void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)

{

	current_info->filename = orig_filename;
@@ -125,28 +109,7 @@ void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum) 
	current_info->checksum = checksum;

}

EXPORT_SYMBOL(llvm_gcda_start_file);

#endif



#if CONFIG_CLANG_VERSION < 110000

void llvm_gcda_emit_function(u32 ident, const char *function_name,

		u32 func_checksum, u8 use_extra_checksum, u32 cfg_checksum)

{

	struct gcov_fn_info *info = kzalloc(sizeof(*info), GFP_KERNEL);



	if (!info)

		return;



	INIT_LIST_HEAD(&info->head);

	info->ident = ident;

	info->checksum = func_checksum;

	info->use_extra_checksum = use_extra_checksum;

	info->cfg_checksum = cfg_checksum;

	if (function_name)

		info->function_name = kstrdup(function_name, GFP_KERNEL);



	list_add_tail(&info->head, &current_info->functions);

}

#else

void llvm_gcda_emit_function(u32 ident, u32 func_checksum, u32 cfg_checksum)

{

	struct gcov_fn_info *info = kzalloc(sizeof(*info), GFP_KERNEL);
@@ -160,7 +123,6 @@ void llvm_gcda_emit_function(u32 ident, u32 func_checksum, u32 cfg_checksum) 
	info->cfg_checksum = cfg_checksum;

	list_add_tail(&info->head, &current_info->functions);

}

#endif

EXPORT_SYMBOL(llvm_gcda_emit_function);



void llvm_gcda_emit_arcs(u32 num_counters, u64 *counters)
@@ -291,16 +253,8 @@ int gcov_info_is_compatible(struct gcov_info *info1, struct gcov_info *info2) 
		!list_is_last(&fn_ptr2->head, &info2->functions)) {

		if (fn_ptr1->checksum != fn_ptr2->checksum)

			return false;

#if CONFIG_CLANG_VERSION < 110000

		if (fn_ptr1->use_extra_checksum != fn_ptr2->use_extra_checksum)

			return false;

		if (fn_ptr1->use_extra_checksum &&

			fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum)

			return false;

#else

		if (fn_ptr1->cfg_checksum != fn_ptr2->cfg_checksum)

			return false;

#endif

		fn_ptr1 = list_next_entry(fn_ptr1, head);

		fn_ptr2 = list_next_entry(fn_ptr2, head);

	}
@@ -329,35 +283,6 @@ void gcov_info_add(struct gcov_info *dst, struct gcov_info *src) 
	}

}



#if CONFIG_CLANG_VERSION < 110000

static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn)

{

	size_t cv_size; /* counter values size */

	struct gcov_fn_info *fn_dup = kmemdup(fn, sizeof(*fn), GFP_KERNEL);



	if (!fn_dup)

		return NULL;

	INIT_LIST_HEAD(&fn_dup->head);



	fn_dup->function_name = kstrdup(fn->function_name, GFP_KERNEL);

	if (!fn_dup->function_name)

		goto err_name;



	cv_size = fn->num_counters * sizeof(fn->counters[0]);

	fn_dup->counters = kvmalloc(cv_size, GFP_KERNEL);

	if (!fn_dup->counters)

		goto err_counters;

	memcpy(fn_dup->counters, fn->counters, cv_size);



	return fn_dup;



err_counters:

	kfree(fn_dup->function_name);

err_name:

	kfree(fn_dup);

	return NULL;

}

#else

static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn)

{

	size_t cv_size; /* counter values size */
@@ -378,7 +303,6 @@ static struct gcov_fn_info *gcov_fn_info_dup(struct gcov_fn_info *fn) 


	return fn_dup;

}

#endif



/**

 * gcov_info_dup - duplicate profiling data set
@@ -419,21 +343,6 @@ struct gcov_info *gcov_info_dup(struct gcov_info *info) 
 * gcov_info_free - release memory for profiling data set duplicate

 * @info: profiling data set duplicate to free

 */

#if CONFIG_CLANG_VERSION < 110000

void gcov_info_free(struct gcov_info *info)

{

	struct gcov_fn_info *fn, *tmp;



	list_for_each_entry_safe(fn, tmp, &info->functions, head) {

		kfree(fn->function_name);

		vfree(fn->counters);

		list_del(&fn->head);

		kfree(fn);

	}

	kfree(info->filename);

	kfree(info);

}

#else

void gcov_info_free(struct gcov_info *info)

{

	struct gcov_fn_info *fn, *tmp;
@@ -446,7 +355,6 @@ void gcov_info_free(struct gcov_info *info) 
	kfree(info->filename);

	kfree(info);

}

#endif



/**

 * convert_to_gcda - convert profiling data set to gcda file format
@@ -469,21 +377,10 @@ size_t convert_to_gcda(char *buffer, struct gcov_info *info) 
		u32 i;



		pos += store_gcov_u32(buffer, pos, GCOV_TAG_FUNCTION);

#if CONFIG_CLANG_VERSION < 110000

		pos += store_gcov_u32(buffer, pos,

			fi_ptr->use_extra_checksum ? 3 : 2);

#else

		pos += store_gcov_u32(buffer, pos, 3);

#endif

		pos += store_gcov_u32(buffer, pos, fi_ptr->ident);

		pos += store_gcov_u32(buffer, pos, fi_ptr->checksum);

#if CONFIG_CLANG_VERSION < 110000

		if (fi_ptr->use_extra_checksum)

			pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);

#else

		pos += store_gcov_u32(buffer, pos, fi_ptr->cfg_checksum);

#endif



		pos += store_gcov_u32(buffer, pos, GCOV_TAG_COUNTER_BASE);

		pos += store_gcov_u32(buffer, pos, fi_ptr->num_counters * 2);

		for (i = 0; i < fi_ptr->num_counters; i++)