From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH v3 2/8] hvmloader: Make the printfs more informative Date: Fri, 21 Jun 2013 10:35:11 +0100 Message-ID: <51C41E4F.2050502@eu.citrix.com> References: <1371746007-19073-1-git-send-email-george.dunlap@eu.citrix.com> <1371746007-19073-3-git-send-email-george.dunlap@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefano Stabellini Cc: Keir Fraser , Ian Campbell , Hanweidong , xen-devel@lists.xen.org, Stefano Stabellini , Ian Jackson List-Id: xen-devel@lists.xenproject.org On 20/06/13 18:12, Stefano Stabellini wrote: > On Thu, 20 Jun 2013, George Dunlap wrote: >> * Warn that you're relocating some BARs to 64-bit >> >> * Warn that you're relocating guest pages, and how many >> >> * Include upper 32-bits of the base register when printing the bar >> placement info >> >> Signed-off-by: George Dunlap >> CC: Ian Campbell >> CC: Ian Jackson >> CC: Stefano Stabellini >> CC: Hanweidong >> CC: Keir Fraser >> --- >> tools/firmware/hvmloader/pci.c | 13 ++++++++++--- >> 1 file changed, 10 insertions(+), 3 deletions(-) >> >> diff --git a/tools/firmware/hvmloader/pci.c b/tools/firmware/hvmloader/pci.c >> index aa54bc1..d8592b0 100644 >> --- a/tools/firmware/hvmloader/pci.c >> +++ b/tools/firmware/hvmloader/pci.c >> @@ -213,10 +213,17 @@ void pci_setup(void) >> ((pci_mem_start << 1) != 0) ) >> pci_mem_start <<= 1; >> >> - if ( (pci_mem_start << 1) != 0 ) >> + if ( (pci_mem_start << 1) != 0 ) { >> + printf("Low MMIO hole not large enough for all devices," >> + " relocating some BARs to 64-bit\n"); >> bar64_relocate = 1; >> + } >> >> /* Relocate RAM that overlaps PCI space (in 64k-page chunks). */ >> + if ( (pci_mem_start >> PAGE_SHIFT) < hvm_info->low_mem_pgend ) >> + printf("Relocating 0x%lx pages to highmem for lowmem MMIO hole\n", >> + hvm_info->low_mem_pgend - (pci_mem_start >> PAGE_SHIFT)); > Shouldn't this be: > > min_t(unsigned int, > hvm_info->low_mem_pgend - (pci_mem_start >> PAGE_SHIFT), > (1u << 16) - 1); > > to match exactly what we do in the relocation code? No; the relocation is done in a loop which will run until the condition in the if above is satisfied. We could, I suppose, do the printf on each iteration of the loop; if I'm doing the math right*, the maximum iterations around the loop should be 8, and a typical number would be just 1 or 2. * Maximum MMIO size: 2GiB == 1<<31. In 4-k pages, that's 1<<(31-12) == 1<<19. This will do a batch of 1<<16 pages at a time, leaving 1<<3 iterations maximum, or 8. (1<<16 pages is 1<<(16+12) or 1<<28 bytes, or 1<<8 == 256 megabytes moved at a time.) > > Regarding the message, what about: > > printf("Relocating 0x%lx pages from 0x%lx to 0x%lx%lx to make room for a larger MMIO hole\n", > min_t(unsigned int, > hvm_info->low_mem_pgend - (pci_mem_start >> PAGE_SHIFT), > (1u << 16) - 1), > hvm_info->low_mem_pgend, > hvm_info->high_mem_pgend); Lemme see how it looks... -George