Messages in this thread | | | Date | Wed, 5 Nov 2014 17:57:26 +0100 | From | Petr Mladek <> | Subject | Re: [RFC][PATCH 09/12 v3] seq_buf: Move the seq_buf code to lib/ |
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On Tue 2014-11-04 10:52:46, Steven Rostedt wrote: > From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org> > > The seq_buf functions are rather useful outside of tracing. Instead > of having it be dependent on CONFIG_TRACING, move the code into lib/ > and allow other users to have access to it even when tracing is not > configured. > > The seq_buf utility is similar to the seq_file utility, but instead of > writing sending data back up to userland, it writes it into a buffer > defined at seq_buf_init(). This allows us to send a descriptor around > that writes printf() formatted strings into it that can be retrieved > later. > > It is currently used by the tracing facility for such things like trace > events to convert its binary saved data in the ring buffer into an > ASCII human readable context to be displayed in /sys/kernel/debug/trace. > > It can also be used for doing NMI prints safely from NMI context into > the seq_buf and retrieved later and dumped to printk() safely. Doing > printk() from an NMI context is dangerous because an NMI can preempt > a current printk() and deadlock on it. > > Link: http://lkml.kernel.org/p/20140619213952.058255809@goodmis.org > > Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch might needed an update when there are changes in the previous patches. But it is a simple file move that makes perfect sense, so:
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Best Regards, Petr
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