From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yinghai Lu Subject: Re: [RFC PATCH -v3 1/2] lmb: seperate region array from lmb_region struct Date: Tue, 23 Mar 2010 22:46:07 -0700 Message-ID: <4BA9A71F.7080801@kernel.org> References: <1269333587-1866-1-git-send-email-yinghai@kernel.org> <1269333587-1866-5-git-send-email-yinghai@kernel.org> <4BA899C2.8020208@kernel.org> <20100323104241.GA1189@elte.hu> <1269405955.8599.156.camel@pasglop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from hera.kernel.org ([140.211.167.34]:43439 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753501Ab0CXFsC (ORCPT ); Wed, 24 Mar 2010 01:48:02 -0400 In-Reply-To: <1269405955.8599.156.camel@pasglop> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Benjamin Herrenschmidt Cc: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Andrew Morton , David Miller , Linus Torvalds , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org On 03/23/2010 09:45 PM, Benjamin Herrenschmidt wrote: > On Tue, 2010-03-23 at 11:42 +0100, Ingo Molnar wrote: >> * Yinghai Lu wrote: >> >>> void __init lmb_init(void) >>> { >>> + lmb.memory.region = lmb_memory_region; >>> + lmb.memory.region_array_size = ARRAY_SIZE(lmb_memory_region); >>> + lmb.reserved.region = lmb_reserved_region; >>> + lmb.reserved.region_array_size = ARRAY_SIZE(lmb_reserved_region); >>> + >> >> That's rather unreadable and has random whitespace noise. >> >> Should be something like: >> >> lmb.memory.region = lmb_memory_region; >> lmb.memory.region_array_size = ARRAY_SIZE(lmb_memory_region); >> lmb.reserved.region = lmb_reserved_region; >> lmb.reserved.region_array_size = ARRAY_SIZE(lmb_reserved_region); >> >> also, i'd suggest to shorten region_array_size to region_size (we know it's an >> array), so it would become: > > I dislike those arrays anyways. See my other message about turning them > into lists, which would get rid of capacity constraints completely. What > do you think ? > 2/2 introduce one new function that could double the array size please check the v4. the function rely on find_lmb_area(). it will check if there is enough space left, otherwise try to get new big array, and copy old array to new array. final function like: static void __init __check_and_double_region_array(struct lmb_region *type, struct lmb_property *static_region, u64 ex_start, u64 ex_end) { u64 start, end, size, mem; struct lmb_property *new, *old; unsigned long rgnsz = type->nr_regions; /* do we have enough slots left ? */ if ((rgnsz - type->cnt) > max_t(unsigned long, rgnsz/8, 2)) return; old = type->region; /* double it */ mem = -1ULL; size = sizeof(struct lmb_property) * rgnsz * 2; if (old == static_region) start = 0; else start = __pa(old) + sizeof(struct lmb_property) * rgnsz; end = ex_start; if (start + size < end) mem = find_lmb_area(start, end, size, sizeof(struct lmb_property)); if (mem == -1ULL) { start = ex_end; end = get_max_mapped(); if (start + size < end) mem = find_lmb_area(start, end, size, sizeof(struct lmb_property)); } if (mem == -1ULL) panic("can not find more space for lmb.reserved.region array"); new = __va(mem); /* copy old to new */ memcpy(&new[0], &old[0], sizeof(struct lmb_property) * rgnsz); memset(&new[rgnsz], 0, sizeof(struct lmb_property) * rgnsz); memset(&old[0], 0, sizeof(struct lmb_property) * rgnsz); type->region = new; type->nr_regions = rgnsz * 2; printk(KERN_DEBUG "lmb.reserved.region array is doubled to %ld at [%llx - %llx]\n", type->nr_regions, mem, mem + size - 1); /* reserve new array and free old one */ lmb_reserve(mem, sizeof(struct lmb_property) * rgnsz * 2); if (old != static_region) lmb_free(__pa(old), sizeof(struct lmb_property) * rgnsz); } void __init add_lmb_memory(u64 start, u64 end) { __check_and_double_region_array(&lmb.memory, &lmb_memory_region[0], start, end); lmb_add(start, end - start); } void __init reserve_early(u64 start, u64 end, char *name) { if (start == end) return; if (WARN_ONCE(start > end, "reserve_early: wrong range [%#llx, %#llx]\n", start, end)) return; __check_and_double_region_array(&lmb.reserved, &lmb_reserved_region[0], start, end); lmb_reserve(start, end - start); } void __init free_early(u64 start, u64 end) { if (start == end) return; if (WARN_ONCE(start > end, "free_early: wrong range [%#llx, %#llx]\n", start, end)) return; /* keep punching hole, could run out of slots too */ __check_and_double_region_array(&lmb.reserved, &lmb_reserved_region[0], start, end); lmb_free(start, end - start); } with those function, we can replace the bootmem in x86. Thanks Yinghai