Am 17/01/2023 um 17:16 schrieb Warner Losh:
>
>
> On Tue, Jan 17, 2023 at 6:52 AM Emanuele Giuseppe Esposito
> <eespo...@redhat.com <mailto:eespo...@redhat.com>> wrote:
>
> QEMU does not compile when enabling clang's thread safety analysis
> (TSA),
> because some functions create wrappers for pthread mutexes but do
> not use any TSA macro. Therefore the compiler fails.
>
> In order to make the compiler happy and avoid adding all the
> necessary macros to all callers (lock functions should use
> TSA_ACQUIRE, while unlock TSA_RELEASE, and this applies to allusers
> of pthread_mutex_lock/pthread_mutex_unlock),
> simply use TSA_NO_TSA to supppress such warnings.
>
>
> I'm not sure I understand this quite right. Maybe a clarifying question
> will help me understand: Why is this needed for bsd-user but not
> linux-user? How are they different here?
>
Honestly I just went and fix the warnings that the compiler was throwing
at me. On FreeBSD it complains on bsd-user/mmap.c, but apparently the CI
or even compiling locally in linux doesn't create any issue with linux-user.
Weird. But I guess it won't hurt to add TSA_NO_TSA there too.
Emanuele
> Warner
>
>
> Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com
> <mailto:eespo...@redhat.com>>
> ---
> bsd-user/qemu.h | 5 +++--
> include/exec/exec-all.h | 5 +++--
> 2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h
> index be6105385e..711fdd1b64 100644
> --- a/bsd-user/qemu.h
> +++ b/bsd-user/qemu.h
> @@ -37,6 +37,7 @@ extern char **environ;
> #include "target_os_signal.h"
> #include "target.h"
> #include "exec/gdbstub.h"
> +#include "qemu/clang-tsa.h"
>
> /*
> * This struct is used to hold certain information about the
> image. Basically,
> @@ -235,8 +236,8 @@ int target_msync(abi_ulong start, abi_ulong len,
> int flags);
> extern unsigned long last_brk;
> extern abi_ulong mmap_next_start;
> abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size);
> -void mmap_fork_start(void);
> -void mmap_fork_end(int child);
> +void TSA_NO_TSA mmap_fork_start(void);
> +void TSA_NO_TSA mmap_fork_end(int child);
>
> /* main.c */
> extern char qemu_proc_pathname[];
> diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
> index 25e11b0a8d..4f0c0559ac 100644
> --- a/include/exec/exec-all.h
> +++ b/include/exec/exec-all.h
> @@ -25,6 +25,7 @@
> #include "exec/cpu_ldst.h"
> #endif
> #include "qemu/interval-tree.h"
> +#include "qemu/clang-tsa.h"
>
> /* allow to see translation results - the slowdown should be
> negligible, so we leave it */
> #define DEBUG_DISAS
> @@ -758,8 +759,8 @@ static inline tb_page_addr_t
> get_page_addr_code(CPUArchState *env,
> }
>
> #if defined(CONFIG_USER_ONLY)
> -void mmap_lock(void);
> -void mmap_unlock(void);
> +void TSA_NO_TSA mmap_lock(void);
> +void TSA_NO_TSA mmap_unlock(void);
> bool have_mmap_lock(void);
>
> /**
> --
> 2.39.0
>
