Messages in this thread | | | From | Vaibhav Nagarnaik <> | Date | Tue, 23 Aug 2011 11:55:02 -0700 | Subject | Re: [PATCH v2 4/5] trace: Make removal of ring buffer pages atomic |
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On Mon, Aug 22, 2011 at 8:27 PM, Steven Rostedt <rostedt@goodmis.org> wrote: > On Tue, 2011-08-16 at 14:46 -0700, Vaibhav Nagarnaik wrote: >> This patch adds the capability to remove pages from a ring buffer >> without destroying any existing data in it. >> >> This is done by removing the pages after the tail page. This makes sure >> that first all the empty pages in the ring buffer are removed. If the >> head page is one in the list of pages to be removed, then the page after >> the removed ones is made the head page. This removes the oldest data >> from the ring buffer and keeps the latest data around to be read. >> >> To do this in a non-racey manner, tracing is stopped for a very short >> time while the pages to be removed are identified and unlinked from the >> ring buffer. The pages are freed after the tracing is restarted to >> minimize the time needed to stop tracing. >> >> The context in which the pages from the per-cpu ring buffer are removed >> runs on the respective CPU. This minimizes the events not traced to only >> NMI trace contexts. > > Could you do the same with this patch, as this one fails to build as > well. And probably should check patch 5 while your at it. > > -- Steve >
I have corrected both the patches. I will make sure that I add 'allyesconfig' and 'allnoconfig' build targets also in my work flow to avoid such issues.
Vaibhav Nagarnaik
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