Re: [Qemu-devel] [PATCH v2 00/11] tcg: Make direct jump patching thread-safe

[Richard Henderson <rth@twiddle.net>]

On 04/22/2016 09:08 AM, Sergey Fedorov wrote:
> When patching translated code for direct block chaining/unchaining,
> modification of concurrently executing code can happen in multi-threaded
> execution.  Currently only user-mode is affected. To make direct block patching
> safe, some care must be taken to make sure that the code modification is made
> atomically and concurrently executed code is guaranteed to be consistent.
>
> This patch series fixes all supported TCG targets which use direct patching and
> documents the requirement for direct jump patching be atomic and thread-safe.
>
> The series' tree can be found in a public git repository [1].
>
> [1]https://github.com/sergefdrv/qemu/tree/atomic-tb-patching-2
>
> Summary of changes in v2:
>   * Take out mistakingly pulled patches [PATCH 01/11] and [PATCH 02/11]
>   * Two new patches to add some handy macros for alignment
>     [PATCH v2 01/11] and [PATCH v2 02/11]
>   * Use new alignment macros instead of open-coding
>   * Use i386 tcg_out_nopn() implementation suggested by Richard Henderson;
>     rework alignment checking and gap calculation in [PATCH v2 05/11]
>   * Clean up reloc_pc24_atomic() in [PATCH v2 07/11]
>   * Use tcg_debug_assert() instead of assert()
>   * Use deposit32() in [PATCH v2 09/11]
>   * s/atomic_write/atomic_set/ in [PATCH v2 10/11]
>   * Minor rewording in [PATCH v2 11/11]

Applied all to tcg-next.  I applied the mips one-liner follow-up at the same time.


r~