Re: [Qemu-devel] [PATCH V7 0/6] coroutine: mmap stack memory and stack size

[Paolo Bonzini]

On 23/08/2016 16:21, Peter Lieven wrote:
> I decided to split this from the rest of the Qemu RSS usage series as
> it contains the more or less non contentious patches.
> 
> I omitted the MAP_GROWSDOWN flag in mmap as we are not 100% sure which
> side effects it has.
> 
> I kept the guard page which is now nicely makes the stacks visible in
> smaps. The old version of the relevent patch lacked the MAP_FIXED flag
> in the second call to mmap.
> 
> The last patch which reduces the stack size of coroutines to 64kB
> may be omitted if its found to risky.
> 
> v6->v6:
>  - Patch 1: avoid multiple calls to sysconf and getpagesize [Richard]
> 
> v5->v6:
>  - Patch 1: added info that the guard page is deducted from stack memory to
>             commit msg and headers [Stefan]
>  - rebased to master
> 
> v4->v5:
>  - Patch 1: check if _SC_THREAD_STACK_MIN is defined
>  - Patch 1: guard against sysconf(_SC_THREAD_STACK_MIN) returning -1 [Eric]
> 
> v3->v4:
>  - Patch 1: add a static function to adjust the stack size [Richard]
>  - Patch 1: round up the stack size to multiple of the pagesize.
> 
> v2->v3:
>  - Patch 1,6: adjusted commit message to mention the guard page [Markus]
> 
> v1->v2:
>  - Patch 1: added an architecture dependend guard page [Richard]
>  - Patch 1: avoid stacks smaller than _SC_THREAD_STACK_MIN [Richard]
>  - Patch 1: use mmap+mprotect instead of mmap+mmap [Richard]
>  - Patch 5: u_int32_t -> uint32_t [Richard]
>  - Patch 5: only available if stack grows down
> 
> Peter Lieven (6):
>   oslib-posix: add helpers for stack alloc and free
>   coroutine: add a macro for the coroutine stack size
>   coroutine-ucontext: use helper for allocating stack memory
>   coroutine-sigaltstack: use helper for allocating stack memory
>   oslib-posix: add a configure switch to debug stack usage
>   coroutine: reduce stack size to 64kB
> 
>  configure                    | 19 ++++++++++
>  include/qemu/coroutine_int.h |  2 ++
>  include/sysemu/os-posix.h    | 27 ++++++++++++++
>  util/coroutine-sigaltstack.c |  7 ++--
>  util/coroutine-ucontext.c    |  9 +++--
>  util/coroutine-win32.c       |  2 +-
>  util/oslib-posix.c           | 84 
> ++++++++++++++++++++++++++++++++++++++++++++
>  7 files changed, 140 insertions(+), 10 deletions(-)
> 

Acked-by: Paolo Bonzini <address@hidden>

I guess Stefan or Kevin will apply it.

Paolo