This new annotation starts just a function wrapper that creates
a new coroutine. It assumes the caller is not a coroutine.
It will be the default annotation to be used in the future.
This is much better as c_w_mixed, because it is clear if the caller
is a coroutine or not, and provides the advantage of automating
the code creation. In the future all c_w_mixed functions will be
substituted by co_wrapper.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
docs/devel/block-coroutine-wrapper.rst | 6 +-
include/block/block-common.h | 8 +-
scripts/block-coroutine-wrapper.py | 110 +++++++++++++++++--------
3 files changed, 86 insertions(+), 38 deletions(-)
diff --git a/docs/devel/block-coroutine-wrapper.rst b/docs/devel/block-coroutine-wrapper.rst
index 64acc8d65d..6dd2cdcab3 100644
--- a/docs/devel/block-coroutine-wrapper.rst
+++ b/docs/devel/block-coroutine-wrapper.rst
@@ -26,12 +26,12 @@ called ``bdrv_foo(<same args>)``. In this case the script can help. To
trigger the generation:
1. You need ``bdrv_foo`` declaration somewhere (for example, in
- ``block/coroutines.h``) with the ``co_wrapper_mixed`` mark,
+ ``block/coroutines.h``) with the ``co_wrapper`` mark,
like this:
.. code-block:: c
- int co_wrapper_mixed bdrv_foo(<some args>);
+ int co_wrapper bdrv_foo(<some args>);
2. You need to feed this declaration to block-coroutine-wrapper script.
For this, add the .h (or .c) file with the declaration to the
@@ -46,7 +46,7 @@ Links
1. The script location is ``scripts/block-coroutine-wrapper.py``.
-2. Generic place for private ``co_wrapper_mixed`` declarations is
+2. Generic place for private ``co_wrapper`` declarations is
``block/coroutines.h``, for public declarations:
``include/block/block.h``
diff --git a/include/block/block-common.h b/include/block/block-common.h
index ec2309055b..847e4d4626 100644
--- a/include/block/block-common.h
+++ b/include/block/block-common.h
@@ -42,9 +42,13 @@
*
* Usage: read docs/devel/block-coroutine-wrapper.rst
*
- * co_wrapper_mixed functions can be called by both coroutine and
- * non-coroutine context.
+ * There are 2 kind of specifiers:
+ * - co_wrapper functions can be called by only non-coroutine context, because
+ * they always generate a new coroutine.
+ * - co_wrapper_mixed functions can be called by both coroutine and
+ * non-coroutine context.
*/
+#define co_wrapper
#define co_wrapper_mixed
/* block.c */
diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py
index 56e6425356..2090c3bf73 100644
--- a/scripts/block-coroutine-wrapper.py
+++ b/scripts/block-coroutine-wrapper.py
@@ -2,7 +2,7 @@
"""Generate coroutine wrappers for block subsystem.
The program parses one or several concatenated c files from stdin,
-searches for functions with the 'co_wrapper_mixed' specifier
+searches for functions with the 'co_wrapper' specifier
and generates corresponding wrappers on stdout.
Usage: block-coroutine-wrapper.py generated-file.c FILE.[ch]...
@@ -62,10 +62,25 @@ def __init__(self, param_decl: str) -> None:
class FuncDecl:
- def __init__(self, return_type: str, name: str, args: str) -> None:
+ def __init__(self, return_type: str, name: str, args: str,
+ variant: str) -> None:
self.return_type = return_type.strip()
self.name = name.strip()
+ self.struct_name = snake_to_camel(self.name)
self.args = [ParamDecl(arg.strip()) for arg in args.split(',')]
+ self.create_only_co = 'mixed' not in variant
+
+ subsystem, subname = self.name.split('_', 1)
+ self.co_name = f'{subsystem}_co_{subname}'
+
+ t = self.args[0].type
+ if t == 'BlockDriverState *':
+ bs = 'bs'
+ elif t == 'BdrvChild *':
+ bs = 'child->bs'
+ else:
+ bs = 'blk_bs(blk)'
+ self.bs = bs
def gen_list(self, format: str) -> str:
return ', '.join(format.format_map(arg.__dict__) for arg in self.args)
@@ -74,8 +89,9 @@ def gen_block(self, format: str) -> str:
return '\n'.join(format.format_map(arg.__dict__) for arg in self.args)
-# Match wrappers declared with a co_wrapper_mixed mark
-func_decl_re = re.compile(r'^int\s*co_wrapper_mixed\s*'
+# Match wrappers declared with a co_wrapper mark
+func_decl_re = re.compile(r'^int\s*co_wrapper'
+ r'(?P<variant>(_[a-z][a-z0-9_]*)?)\s*'
r'(?P<wrapper_name>[a-z][a-z0-9_]*)'
r'\((?P<args>[^)]*)\);$', re.MULTILINE)
@@ -84,7 +100,8 @@ def func_decl_iter(text: str) -> Iterator:
for m in func_decl_re.finditer(text):
yield FuncDecl(return_type='int',
name=m.group('wrapper_name'),
- args=m.group('args'))
+ args=m.group('args'),
+ variant=m.group('variant'))
def snake_to_camel(func_name: str) -> str:
@@ -97,24 +114,67 @@ def snake_to_camel(func_name: str) -> str:
return ''.join(words)
+def create_mixed_wrapper(func: FuncDecl) -> str:
+ """
+ Checks if we are already in coroutine
+ """
+ name = func.co_name
+ struct_name = func.struct_name
+ return f"""\
+int {func.name}({ func.gen_list('{decl}') })
+{{
+ if (qemu_in_coroutine()) {{
+ return {name}({ func.gen_list('{name}') });
+ }} else {{
+ {struct_name} s = {{
+ .poll_state.bs = {func.bs},
+ .poll_state.in_progress = true,
+
+{ func.gen_block(' .{name} = {name},') }
+ }};
+
+ s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
+
+ return bdrv_poll_co(&s.poll_state);
+ }}
+}}"""
+
+
+def create_co_wrapper(func: FuncDecl) -> str:
+ """
+ Assumes we are not in coroutine, and creates one
+ """
+ name = func.co_name
+ struct_name = func.struct_name
+ return f"""\
+int {func.name}({ func.gen_list('{decl}') })
+{{
+ {struct_name} s = {{
+ .poll_state.bs = {func.bs},
+ .poll_state.in_progress = true,
+
+{ func.gen_block(' .{name} = {name},') }
+ }};
+ assert(!qemu_in_coroutine());
+
+ s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
+
+ return bdrv_poll_co(&s.poll_state);
+}}"""
+
+
def gen_wrapper(func: FuncDecl) -> str:
assert not '_co_' in func.name
assert func.return_type == 'int'
assert func.args[0].type in ['BlockDriverState *', 'BdrvChild *',
'BlockBackend *']
- subsystem, subname = func.name.split('_', 1)
-
- name = f'{subsystem}_co_{subname}'
+ name = func.co_name
+ struct_name = func.struct_name
- t = func.args[0].type
- if t == 'BlockDriverState *':
- bs = 'bs'
- elif t == 'BdrvChild *':
- bs = 'child->bs'
- else:
- bs = 'blk_bs(blk)'
- struct_name = snake_to_camel(name)
+ creation_function = create_mixed_wrapper
+ if func.create_only_co:
+ creation_function = create_co_wrapper
return f"""\
/*
@@ -136,23 +196,7 @@ def gen_wrapper(func: FuncDecl) -> str:
aio_wait_kick();
}}
-int {func.name}({ func.gen_list('{decl}') })
-{{
- if (qemu_in_coroutine()) {{
- return {name}({ func.gen_list('{name}') });
- }} else {{
- {struct_name} s = {{
- .poll_state.bs = {bs},
- .poll_state.in_progress = true,
-
-{ func.gen_block(' .{name} = {name},') }
- }};
-
- s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
-
- return bdrv_poll_co(&s.poll_state);
- }}
-}}"""
+{creation_function(func)}"""
def gen_wrappers(input_code: str) -> str:
--
2.31.1