Paul Mackerras wrote:
Commit-ID: 03ced439c94d692363307eeb3abe0bbfa2d08a01 Gitweb: http://git.kernel.org/tip/03ced439c94d692363307eeb3abe0bbfa2d08a01 Author: Paul Mackerras <paulus@xxxxxxxxx> AuthorDate: Wed, 25 Mar 2009 22:46:58 +1100 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Wed, 25 Mar 2009 13:24:00 +0100 perf_counter: record time running and time enabled for each counter
[snip]
These values can be supplied to userspace on a read from the counter. Userspace requests that they be supplied after the counter value by setting the PERF_FORMAT_TOTAL_TIME_ENABLED and/or PERF_FORMAT_TOTAL_TIME_RUNNING bits in the hw_event.read_format field when creating the counter. (There is no way to change the read format after the counter is created, though it would be possible to add some way to do that.)
This change looks good to me, except:How do I know which value comes first after the counter value if I have both PERF_FORMAT_TOTAL_TIME_ENABLED and PERF_FORMAT_TOTAL_TIME_RUNNING set? Are they in the order of their enum values? The order should be described somewhere. Is there anything to keep a kernel code change from inadvertantly reversing the position of two values at some point in the future?
Regards, - Corey Corey Ashford Software Engineer IBM Linux Technology Center, Linux Toolchain Beaverton, OR 503-578-3507 cjashfor@xxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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