From b1a68aebadecd7d339cf5eaffeda15099c998528 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Tue, 12 Sep 2023 19:10:37 -0400 Subject: [PATCH 095/101] block-coroutine-wrapper: use qemu_get_current_aio_context() RH-Author: Kevin Wolf RH-MergeRequest: 214: Remove AioContext lock RH-Jira: RHEL-15965 RH-Acked-by: Miroslav Rezanina RH-Acked-by: Stefan Hajnoczi RH-Commit: [26/26] cde767bcdc626e90721792e3889952057a548ac5 (kmwolf/centos-qemu-kvm) Use qemu_get_current_aio_context() in mixed wrappers and coroutine wrappers so that code runs in the caller's AioContext instead of moving to the BlockDriverState's AioContext. This change is necessary for the multi-queue block layer where any thread can call into the block layer. Most wrappers are IO_CODE where it's safe to use the current AioContext nowadays. BlockDrivers and the core block layer use their own locks and no longer depend on the AioContext lock for thread-safety. The bdrv_create() wrapper invokes GLOBAL_STATE code. Using the current AioContext is safe because this code is only called with the BQL held from the main loop thread. Signed-off-by: Stefan Hajnoczi Message-ID: <20230912231037.826804-6-stefanha@redhat.com> Reviewed-by: Eric Blake Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- scripts/block-coroutine-wrapper.py | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index c9c09fcacd..dbbde99e39 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -92,8 +92,6 @@ def __init__(self, wrapper_type: str, return_type: str, name: str, f"{self.name}") self.target_name = f'{subsystem}_{subname}' - self.ctx = self.gen_ctx() - self.get_result = 's->ret = ' self.ret = 'return s.ret;' self.co_ret = 'return ' @@ -167,7 +165,7 @@ def create_mixed_wrapper(func: FuncDecl) -> str: {func.co_ret}{name}({ func.gen_list('{name}') }); }} else {{ {struct_name} s = {{ - .poll_state.ctx = {func.ctx}, + .poll_state.ctx = qemu_get_current_aio_context(), .poll_state.in_progress = true, { func.gen_block(' .{name} = {name},') } @@ -191,7 +189,7 @@ def create_co_wrapper(func: FuncDecl) -> str: {func.return_type} {func.name}({ func.gen_list('{decl}') }) {{ {struct_name} s = {{ - .poll_state.ctx = {func.ctx}, + .poll_state.ctx = qemu_get_current_aio_context(), .poll_state.in_progress = true, { func.gen_block(' .{name} = {name},') } -- 2.39.3