| Message ID | 20220114153732.3767229-2-peter.maydell@linaro.org |
|---|---|
| State | Accepted |
| Headers | show |
| Series | linux-user: Fix some minor nits | expand |
Le 14/01/2022 à 16:37, Peter Maydell a écrit : > The linux-user struct TaskState has an 'aligned(16)' attribute. When > the struct was first added in commit 851e67a1b46f in 2003, there was > a justification in a comment (still present in the source today): > > /* NOTE: we force a big alignment so that the stack stored after is > aligned too */ > > because the final field in the struct was "uint8_t stack[0];" > But that field was removed in commit 48e15fc2d in 2010 which > switched us to allocating the stack and the TaskState separately. > Because we allocate the structure with g_new0() rather than as > a local variable, the attribute made no difference to the alignment > of the structure anyway. > > Remove the unnecessary attribute, and the corresponding comment. > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > linux-user/qemu.h | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/linux-user/qemu.h b/linux-user/qemu.h > index 5c713fa8ab2..bd0559759ae 100644 > --- a/linux-user/qemu.h > +++ b/linux-user/qemu.h > @@ -96,10 +96,6 @@ struct emulated_sigtable { > target_siginfo_t info; > }; > > -/* > - * NOTE: we force a big alignment so that the stack stored after is > - * aligned too > - */ > typedef struct TaskState { > pid_t ts_tid; /* tid (or pid) of this task */ > #ifdef TARGET_ARM > @@ -160,7 +156,7 @@ typedef struct TaskState { > > /* This thread's sigaltstack, if it has one */ > struct target_sigaltstack sigaltstack_used; > -} __attribute__((aligned(16))) TaskState; > +} TaskState; > > abi_long do_brk(abi_ulong new_brk); > Applied to my linux-user-for-7.0 branch. Thanks, Laurent
diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 5c713fa8ab2..bd0559759ae 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -96,10 +96,6 @@ struct emulated_sigtable { target_siginfo_t info; }; -/* - * NOTE: we force a big alignment so that the stack stored after is - * aligned too - */ typedef struct TaskState { pid_t ts_tid; /* tid (or pid) of this task */ #ifdef TARGET_ARM @@ -160,7 +156,7 @@ typedef struct TaskState { /* This thread's sigaltstack, if it has one */ struct target_sigaltstack sigaltstack_used; -} __attribute__((aligned(16))) TaskState; +} TaskState; abi_long do_brk(abi_ulong new_brk);
The linux-user struct TaskState has an 'aligned(16)' attribute. When the struct was first added in commit 851e67a1b46f in 2003, there was a justification in a comment (still present in the source today): /* NOTE: we force a big alignment so that the stack stored after is aligned too */ because the final field in the struct was "uint8_t stack[0];" But that field was removed in commit 48e15fc2d in 2010 which switched us to allocating the stack and the TaskState separately. Because we allocate the structure with g_new0() rather than as a local variable, the attribute made no difference to the alignment of the structure anyway. Remove the unnecessary attribute, and the corresponding comment. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- linux-user/qemu.h | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)