From mboxrd@z Thu Jan 1 00:00:00 1970 From: cl@linux.com (Christoph Lameter) Date: Thu, 30 Apr 2009 12:08:51 -0400 (EDT) Subject: [ltt-dev] [PATCH] Fix dirty page accounting in redirty_page_for_writepage() In-Reply-To: <20090430160054.GB4723@elte.hu> References: <20090430024303.GB19875@Krystal> <20090430133859.GB8329@elte.hu> <20090430141446.GD14696@elte.hu> <20090430143819.GF14696@elte.hu> <20090430150142.GC20580@elte.hu> <20090430160054.GB4723@elte.hu> Message-ID: On Thu, 30 Apr 2009, Ingo Molnar wrote: > The new percpu APIs could be used in most of these places already, > straight away. This is a really good TODO list for places to > enhance. Please look a the full list in the cpu alloc v3 patchset and not only those that I listed here. > Then a second set of patches could convert percpu_add() / etc. uses > to __percpu_add() ... but that should be done by those architectures > that need it (and to the extent they need it), because it's not > really testable on x86. Ok So we convert it and wait until the arch maintainers complain? I definitely know that there is an IA64 issue with vm statistics. > I dont really like the PER_CPU / CPU_INC etc. type of all-capitals > APIs you introduced in the patches above: I know. Patches would have to be redone against whatever API we agree on. > > + __CPU_INC(bt->sequence); > + CPU_FREE(bt->sequence); > > was there any strong reason to go outside the well-established > percpu_* name space and call these primitives as if they were > macros? They are macros and may do weird things with the variables. This goes back to our disagreement last year on caps/lower case. I still think this kind of preprocessor magic should be uppercase. The reason not to use the percpu_* names was that they were x86 arch specific (and thus not available) and did not differentiate in terms of the irq/preemption context.