Messages in this thread | | | Date | Thu, 30 May 2013 11:48:50 -0400 | From | Waiman Long <> | Subject | Re: [PATCH 0/3 v3] dcache: make it more scalable on large system |
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On 05/29/2013 05:19 PM, Jörn Engel wrote: > On Wed, 29 May 2013 22:37:00 +0200, Andi Kleen wrote: >>> As Dave said before, is the last path component sufficient? Or how >>> about an inode number? >> Neither works, the profiler needs to find the file and read it. > Ignoring all the complexity this would cause downstream, you could do > the path lookup just once, attach some cookie to it and return the > cookie ever-after. Maybe some combination of i_sb and i_ino would be > good enough as a cookie.
Still, it is just shifting the complexity from the d_path code to the perf kernel subsystem as it needs to keep track of what paths have been sent up before. It also have complications in case the tracked files are being deleted or moved around in the filesystem. Some kind of notification mechanism has to be implemented in the dentry layer to notify the perf subsystem.
Regards, Longman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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