2021-04-07 21:55:31

by Nick Desaulniers

Subject: [PATCH 2/2] gcov: re-drop support for clang-10

LLVM changed the expected function signatures for
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.

Signed-off-by: Nick Desaulniers <[email protected]>
---
kernel/gcov/clang.c | 40 ----------------------------------------
1 file changed, 40 deletions(-)

diff --git a/kernel/gcov/clang.c b/kernel/gcov/clang.c
index 1747204541bf..78c4dc751080 100644
--- a/kernel/gcov/clang.c
+++ b/kernel/gcov/clang.c
@@ -69,9 +69,6 @@ struct gcov_fn_info {

u32 ident;
u32 checksum;
-#if CONFIG_CLANG_VERSION < 110000
- u8 use_extra_checksum;
-#endif
u32 cfg_checksum;

u32 num_counters;
@@ -113,23 +110,6 @@ void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
}
EXPORT_SYMBOL(llvm_gcda_start_file);

-#if CONFIG_CLANG_VERSION < 110000
-void llvm_gcda_emit_function(u32 ident, 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;
- 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);
@@ -143,7 +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)
@@ -274,16 +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);
}
@@ -403,21 +374,10 @@ 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++)
--
2.31.1.295.g9ea45b61b8-goog

2021-04-07 21:58:43

by Fangrui Song

Subject: Re: [PATCH 2/2] gcov: re-drop support for clang-10

On 2021-04-07, Nick Desaulniers wrote:
>LLVM changed the expected function signatures for
>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.
>
>Signed-off-by: Nick Desaulniers <[email protected]>
>---
> kernel/gcov/clang.c | 40 ----------------------------------------
> 1 file changed, 40 deletions(-)
>
>diff --git a/kernel/gcov/clang.c b/kernel/gcov/clang.c
>index 1747204541bf..78c4dc751080 100644
>--- a/kernel/gcov/clang.c
>+++ b/kernel/gcov/clang.c
>@@ -69,9 +69,6 @@ struct gcov_fn_info {
>
> u32 ident;
> u32 checksum;
>-#if CONFIG_CLANG_VERSION < 110000
>- u8 use_extra_checksum;
>-#endif
> u32 cfg_checksum;
>
> u32 num_counters;
>@@ -113,23 +110,6 @@ void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
> }
> EXPORT_SYMBOL(llvm_gcda_start_file);
>
>-#if CONFIG_CLANG_VERSION < 110000
>-void llvm_gcda_emit_function(u32 ident, 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;
>- 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);
>@@ -143,7 +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)
>@@ -274,16 +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);
> }
>@@ -403,21 +374,10 @@ 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++)
>--
>2.31.1.295.g9ea45b61b8-goog
>

Looks good for both. Thanks!

Reviewed-by: Fangrui Song <[email protected]>

2021-04-07 21:59:20

by Nathan Chancellor

Subject: Re: [PATCH 2/2] gcov: re-drop support for clang-10

On Wed, Apr 07, 2021 at 11:54:56AM -0700, Nick Desaulniers wrote:
> LLVM changed the expected function signatures for
> 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.
>
> Signed-off-by: Nick Desaulniers <[email protected]>

Reviewed-by: Nathan Chancellor <[email protected]>

> ---
> kernel/gcov/clang.c | 40 ----------------------------------------
> 1 file changed, 40 deletions(-)
>
> diff --git a/kernel/gcov/clang.c b/kernel/gcov/clang.c
> index 1747204541bf..78c4dc751080 100644
> --- a/kernel/gcov/clang.c
> +++ b/kernel/gcov/clang.c
> @@ -69,9 +69,6 @@ struct gcov_fn_info {
>
> u32 ident;
> u32 checksum;
> -#if CONFIG_CLANG_VERSION < 110000
> - u8 use_extra_checksum;
> -#endif
> u32 cfg_checksum;
>
> u32 num_counters;
> @@ -113,23 +110,6 @@ void llvm_gcda_start_file(const char *orig_filename, u32 version, u32 checksum)
> }
> EXPORT_SYMBOL(llvm_gcda_start_file);
>
> -#if CONFIG_CLANG_VERSION < 110000
> -void llvm_gcda_emit_function(u32 ident, 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;
> - 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);
> @@ -143,7 +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)
> @@ -274,16 +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);
> }
> @@ -403,21 +374,10 @@ 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++)
> --
> 2.31.1.295.g9ea45b61b8-goog
>