> Given the above, some basic suggestions for page-based memory management: > > (a) If you need to allocate or free a single page, use the single page > version of the routine/macro, rather than calling the multi-page > version with an order value of zero, such as: > > alloc_pages(gfp_mask, 0); /* no */ > alloc_page(gfp_mask); /* better */ > > (b) If you need to allocate a single zeroed page by logical address, > use get_zeroed_page(), rather than __get_free_page() followed > by a call to memset() to clear that page.
both look good... I'd be in favor of this. Maybe also add a part about using GFP_KERNEL whenever possible, GFP_NOFS from filesystem writeout code and GFP_NOIO from block writeout code (and never doing in_interrupt()?GFP_ATOMIC:GFP_KERNEL !) > > (c) If you need to specifically allocate some DMA pages, use the > __get_dma_pages() macro, as in: > > __get_free_pages(GFP_KERNEL|GFP_DMA, order) /* no */ > __get_dma_pages(GFP_KERNEL, order) /* better */ this.. does not really. GFP_DMA is an ancient artifact from the ISA days. Better to describe the dma mapping interface (well give a pointer to the doc that already exists about that), that one is REALLY for allocating dma pages in this century. -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
