diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-12-08 18:25:06 +0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2012-12-08 18:25:06 +0400 |
| commit | f0b9abfb044649bc452fb2fb975ff2fd599cc6a3 (patch) | |
| tree | 7800081c5cb16a4dfee1e57a70f3be90f7b50d9a /arch/sparc/include/asm/processor_64.h | |
| parent | adc1ef1e37358d3c17d1a74a58b2e104fc0bda15 (diff) | |
| parent | 1b3c393cd43f22ead8a6a2f839efc6df8ebd7465 (diff) | |
| download | linux-f0b9abfb044649bc452fb2fb975ff2fd599cc6a3.tar.xz | |
Merge branch 'linus' into perf/core
Conflicts:
tools/perf/Makefile
tools/perf/builtin-test.c
tools/perf/perf.h
tools/perf/tests/parse-events.c
tools/perf/util/evsel.h
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/sparc/include/asm/processor_64.h')
| -rw-r--r-- | arch/sparc/include/asm/processor_64.h | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/arch/sparc/include/asm/processor_64.h b/arch/sparc/include/asm/processor_64.h index 4e5a483122a0..721e25f0e2ea 100644 --- a/arch/sparc/include/asm/processor_64.h +++ b/arch/sparc/include/asm/processor_64.h @@ -196,7 +196,22 @@ extern unsigned long get_wchan(struct task_struct *task); #define KSTK_EIP(tsk) (task_pt_regs(tsk)->tpc) #define KSTK_ESP(tsk) (task_pt_regs(tsk)->u_regs[UREG_FP]) -#define cpu_relax() barrier() +/* Please see the commentary in asm/backoff.h for a description of + * what these instructions are doing and how they have been choosen. + * To make a long story short, we are trying to yield the current cpu + * strand during busy loops. + */ +#define cpu_relax() asm volatile("\n99:\n\t" \ + "rd %%ccr, %%g0\n\t" \ + "rd %%ccr, %%g0\n\t" \ + "rd %%ccr, %%g0\n\t" \ + ".section .pause_3insn_patch,\"ax\"\n\t"\ + ".word 99b\n\t" \ + "wr %%g0, 128, %%asr27\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + ".previous" \ + ::: "memory") /* Prefetch support. This is tuned for UltraSPARC-III and later. * UltraSPARC-I will treat these as nops, and UltraSPARC-II has |