[Mesa-dev] [PATCH 07/13] mesa: Replace program locks with atomic inc/dec.

[Timothy Arceri]

There are still some issues with the other patches but is there any
reason this one didn't land?

On Thu, 2015-08-06 at 17:10 -0700, Matt Turner wrote:
> ---
>  src/mesa/main/mtypes.h     |  1 -
>  src/mesa/program/program.c | 15 +++------------
>  2 files changed, 3 insertions(+), 13 deletions(-)
> 
> diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
> index fcc527f..c597ccc 100644
> --- a/src/mesa/main/mtypes.h
> +++ b/src/mesa/main/mtypes.h
> @@ -2095,7 +2095,6 @@ enum gl_frag_depth_layout
>   */
>  struct gl_program
>  {
> -   mtx_t Mutex;
>     GLuint Id;
>     GLint RefCount;
>     GLubyte *String;  /**< Null-terminated program text */
> diff --git a/src/mesa/program/program.c b/src/mesa/program/program.c
> index e94c102..54e3498 100644
> --- a/src/mesa/program/program.c
> +++ b/src/mesa/program/program.c
> @@ -38,6 +38,7 @@
>  #include "prog_parameter.h"
>  #include "prog_instruction.h"
>  #include "util/ralloc.h"
> +#include "util/u_atomic.h"
>  
>  
>  /**
> @@ -226,7 +227,6 @@ init_program_struct(struct gl_program *prog,
> GLenum target, GLuint id)
>     assert(prog);
>  
>     memset(prog, 0, sizeof(*prog));
> -   mtx_init(&prog->Mutex, mtx_plain);
>     prog->Id = id;
>     prog->Target = target;
>     prog->RefCount = 1;
> @@ -419,7 +419,6 @@ _mesa_delete_program(struct gl_context *ctx,
> struct gl_program *prog)
>        ralloc_free(prog->nir);
>     }
>  
> -   mtx_destroy(&prog->Mutex);
>     free(prog);
>  }
>  
> @@ -464,17 +463,11 @@ _mesa_reference_program_(struct gl_context
> *ctx,
>  #endif
>  
>     if (*ptr) {
> -      GLboolean deleteFlag;
>        struct gl_program *oldProg = *ptr;
>  
> -      mtx_lock(&oldProg->Mutex);
>        assert(oldProg->RefCount > 0);
> -      oldProg->RefCount--;
>  
> -      deleteFlag = (oldProg->RefCount == 0);
> -      mtx_unlock(&oldProg->Mutex);
> -
> -      if (deleteFlag) {
> +      if (p_atomic_dec_zero(&oldProg->RefCount)) {
>           assert(ctx);
>           ctx->Driver.DeleteProgram(ctx, oldProg);
>        }
> @@ -484,9 +477,7 @@ _mesa_reference_program_(struct gl_context *ctx,
>  
>     assert(!*ptr);
>     if (prog) {
> -      mtx_lock(&prog->Mutex);
> -      prog->RefCount++;
> -      mtx_unlock(&prog->Mutex);
> +      p_atomic_inc(&prog->RefCount);
>     }
>  
>     *ptr = prog;