From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pa0-x244.google.com ([2607:f8b0:400e:c03::244]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aHbIa-0007td-DM for linux-mtd@lists.infradead.org; Fri, 08 Jan 2016 17:58:04 +0000 Received: by mail-pa0-x244.google.com with SMTP id pv5so22821242pac.0 for ; Fri, 08 Jan 2016 09:57:44 -0800 (PST) Date: Fri, 8 Jan 2016 09:57:41 -0800 From: Brian Norris To: Richard Weinberger Cc: Daniel Walter , "linux-mtd@lists.infradead.org" Subject: Re: [RFC] [PATCH] mtd: add tracepoints for mtd_read and mtd_write Message-ID: <20160108175741.GO109450@google.com> References: <20151117191448.GA5367@dw-nb.local> <20151117191801.GA864@dw-nb.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Jan 08, 2016 at 10:33:03AM +0100, Richard Weinberger wrote: > On Tue, Nov 17, 2015 at 8:18 PM, Daniel Walter wrote: > > Add tracepoints to mtd subsystem for read and write > > operations. This should allow us to identify applications > > which are generating too much reads/writes on a flash-device. > > > > Signed-off-by: Daniel Walter > > Brian, any comments on this? Only a few. I'm not very familiar with writing trace events. I've only barely used them! And I haven't run this patch yet. But I thought Daniel reported having some difficulty here -- that it isn't actually that useful to get real "user" information, since most writing/erasing happens from background UBI tasks in practice. So is this still the best mechanism for tracking this information? (Even if there's better ways to get info directly out of UBI, I guess maybe it'd still be good to have this infrastructure.) Also, maybe I'm missing something, but it doesn't look like this attempts to record *which* MTD is being accessed, right? I'd think logging mtd->name could help? Brian