[PATCH 1/4, libgomp] Resolve deadlock on plugin exit

[Martin Jambor]

Hi,

On Mon, Mar 21, 2016 at 06:21:02PM +0800, Chung-Lin Tang wrote:
> Hi, this is the set of patches from https://gcc.gnu.org/ml/gcc-patches/2015-12/msg01411.html
> revised again, this time also with audits for the HSA plugin.
> 
> The changes are pretty minor, mainly that the unload_image hook now
> receives similar error handling treatment.
> 
> Tested again without regressions for nvptx and intelmic, however
> while I was able to build the toolchain with HSA offloading support, I was
> unsure how I could test it, as I currently don't have any AMD hardware (not
> aware if there's an emulator like intelmic).  I would be grateful if
> the HSA folks can run them for me.

I have just tested the whole patch-set on my HSA box (i.e. gomp.exp
tests and all libgomp tests on trunk + some extra testing on the hsa
branch) and found no issues.

I have had a very superficial look over the patch and have no
objections but since I am not familiar with the issue this addresses
and because I do not have detailed understanding of the of internals
of copying data to/from devices, my opinion should not really count
much.

Nevertheless, thanks for thinking about HSA and making me aware of the
change,

Martin


> 
> Thanks,
> Chung-Lin
> 
> ChangeLog for the libgomp proper parts, patch as attached.
> 
> 2016-03-20  Chung-Lin Tang  <cltang@codesourcery.com>
> 
>         * target.c (gomp_device_copy): New function.
>         (gomp_copy_host2dev): Likewise.
>         (gomp_copy_dev2host): Likewise.
>         (gomp_free_device_memory): Likewise.
>         (gomp_map_vars_existing): Adjust to call gomp_copy_host2dev().
>         (gomp_map_pointer): Likewise.
>         (gomp_map_vars): Adjust to call gomp_copy_host2dev(), handle
>         NULL value from alloc_func plugin hook.
>         (gomp_unmap_tgt): Adjust to call gomp_free_device_memory().
>         (gomp_copy_from_async): Adjust to call gomp_copy_dev2host().
>         (gomp_unmap_vars): Likewise.
>         (gomp_update): Adjust to call gomp_copy_dev2host() and
>         gomp_copy_host2dev() functions.
>         (gomp_unload_image_from_device): Handle false value from
>         unload_image_func plugin hook.
>         (gomp_init_device): Handle false value from init_device_func
>         plugin hook.
>         (gomp_exit_data): Adjust to call gomp_copy_dev2host().
>         (omp_target_free): Adjust to call gomp_free_device_memory().
>         (omp_target_memcpy): Handle return values from host2dev_func,
>         dev2host_func, and dev2dev_func plugin hooks.
>         (omp_target_memcpy_rect_worker): Likewise.
>         (gomp_target_fini): Handle false value from fini_device_func
>         plugin hook.
>         * libgomp.h (struct gomp_device_descr): Adjust return type of
>         init_device_func, fini_device_func, unload_image_func, free_func,
>         dev2host_func,host2dev_func, and dev2dev_func plugin hooks to 'bool'.
>         * oacc-host.c (host_init_device): Change return type to bool.
>         (host_fini_device): Likewise.
>         (host_unload_image): Likewise.
>         (host_free): Likewise.
>         (host_dev2host): Likewise.
>         (host_host2dev): Likewise.
>         * oacc-mem.c (acc_free): Handle plugin hook fatal error case.
>         (acc_memcpy_to_device): Likewise.
>         (acc_memcpy_from_device): Likewise.
>         (delete_copyout): Add libfnname parameter, handle free_func
>         hook fatal error case.
>         (acc_delete): Adjust delete_copyout call.
>         (acc_copyout): Likewise.
>         (update_dev_host): Move gomp_mutex_unlock to after
>         host2dev/dev2host hook calls.
>