From 867672777964b9309e4e914fe097648c938b67b2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 4 Oct 2006 17:26:21 +0200 Subject: [POWERPC] spufs: add infrastructure for finding elf objects This adds an 'object-id' file that the spe library can use to store a pointer to its ELF object. This was originally meant for use by oprofile, but is now also used by the GNU debugger, if available. In order for oprofile to find the location in an spu-elf binary where an event counter triggered, we need a way to identify the binary in the first place. Unfortunately, that binary itself can be embedded in a powerpc ELF binary. Since we can assume it is mapped into the effective address space of the running process, have that one write the pointer value into a new spufs file. When a context switch occurs, pass the user value to the profiler so that can look at the mapped file (with some care). Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras --- include/asm-powerpc/spu.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include/asm-powerpc') diff --git a/include/asm-powerpc/spu.h b/include/asm-powerpc/spu.h index 83b6dae48efc..e73ea00efd8b 100644 --- a/include/asm-powerpc/spu.h +++ b/include/asm-powerpc/spu.h @@ -200,6 +200,24 @@ static inline void unregister_spu_syscalls(struct spufs_calls *calls) #endif /* MODULE */ +/* + * Notifier blocks: + * + * oprofile can get notified when a context switch is performed + * on an spe. The notifer function that gets called is passed + * a pointer to the SPU structure as well as the object-id that + * identifies the binary running on that SPU now. + * + * For a context save, the object-id that is passed is zero, + * identifying that the kernel will run from that moment on. + * + * For a context restore, the object-id is the value written + * to object-id spufs file from user space and the notifer + * function can assume that spu->ctx is valid. + */ +int spu_switch_event_register(struct notifier_block * n); +int spu_switch_event_unregister(struct notifier_block * n); + /* * This defines the Local Store, Problem Area and Privlege Area of an SPU. */ -- cgit v1.2.2