On Fri, Sep 25, 2015 at 1:08 PM +0800, Wood Scott-B07421 wrote: > -----Original Message----- > From: Wood Scott-B07421 > Sent: Friday, September 25, 2015 1:08 PM > To: Zhao Qiang-B45475 > Cc: linux-ker...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; > lau...@codeaurora.org; Xie Xiaobo-R63061; b...@kernel.crashing.org; Li > Yang-Leo-R58472; pau...@samba.org > Subject: Re: [PATCH v10 3/5] CPM/QE: use genalloc to manage CPM/QE muram > > On Thu, 2015-09-24 at 21:50 -0500, Zhao Qiang-B45475 wrote: > > On Fri, Sep 25, 2015 at 7:30 AM +0800, Wood Scott-B07421 wrote: > > > -----Original Message----- > > > From: Wood Scott-B07421 > > > Sent: Friday, September 25, 2015 7:30 AM > > > To: Zhao Qiang-B45475 > > > Cc: linux-ker...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; > > > lau...@codeaurora.org; Xie Xiaobo-R63061; b...@kernel.crashing.org; > > > Li Yang-Leo-R58472; pau...@samba.org > > > Subject: Re: [PATCH v10 3/5] CPM/QE: use genalloc to manage CPM/QE > > > muram > > > > > > On Wed, 2015-09-23 at 00:28 -0500, Zhao Qiang-B45475 wrote: > > > > On Wen, Sep 23, 2015 at 12:03 AM +0800, Wood Scott-B07421 wrote: > > > > > > > > > -----Original Message----- > > > > > From: Wood Scott-B07421 > > > > > Sent: Wednesday, September 23, 2015 12:03 PM > > > > > To: Zhao Qiang-B45475 > > > > > Cc: linux-ker...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org; > > > > > lau...@codeaurora.org; Xie Xiaobo-R63061; > > > > > b...@kernel.crashing.org; Li Yang-Leo-R58472; pau...@samba.org > > > > > Subject: Re: [PATCH v10 3/5] CPM/QE: use genalloc to manage > > > > > CPM/QE muram > > > > > > > > > > On Tue, 2015-09-22 at 21:20 -0500, Zhao Qiang-B45475 wrote: > > > > > > On Wen, Sep 23, 2015 at 8:19 AM +0800, Wood Scott-B07421 wrote: > > > > > > > > > > > > > > > > { > > > > > > > > > > - int ret; > > > > > > > > > > + > > > > > > > > > > + unsigned long start; > > > > > > > > > > unsigned long flags; > > > > > > > > > > + unsigned long size_alloc = size; struct muram_block > > > > > > > > > > + *entry; int end_bit; int order = > > > > > > > > > > + muram_pool->min_alloc_order; > > > > > > > > > > > > > > > > > > > > spin_lock_irqsave(&cpm_muram_lock, flags); > > > > > > > > > > - ret = rh_free(&cpm_muram_info, offset); > > > > > > > > > > + end_bit = (offset >> order) + ((size + (1UL << > > > > > > > > > > + order) - > > > > > > > > > > + 1) > > > > > > > > > > + >> > > > > > > > > > order); > > > > > > > > > > + if ((offset + size) > (end_bit << order)) > > > > > > > > > > + size_alloc = size + (1UL << order); > > > > > > > > > > > > > > > > > > Why do you need to do all these calculations here? > > > > > > > > > > > > > > > > So do it in gen_pool_fixed_alloc? > > > > > > > > > > > > > > Could you explain why they're needed at all? > > > > > > > > > > > > Why it does the calculations? > > > > > > If the min block of gen_pool is 8 bytes, and I want to > > > > > > allocate a Region with offset=7, size=8bytes, I actually need > > > > > > block 0 and block 1, And the allocation will give me block 0. > > > > > > > > > > How can you have offset 7 if the minimum order is 2 bytes? > > > > > > > > Offset has no relationship with minimum order, it is not decided > > > > by minimum order. > > > > > > All allocations begin and end on a multiple of the minimum order. > > > > So it is the problem. CPM require to allocate a specific region, who > > can ensure that the specific is just the begin of minimum order. > > Do you have any reason to believe that there is any caller of this > function with an odd address? > > If so, set the minimum order to zero. If not, what is the problem?
Setting minimum order to zero is ok. -Zhao _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev