Acked-by: George Dunlap <george.dunlap@xxxxxxxxxxxxx>
On Tue, May 10, 2011 at 3:32 PM, Olaf Hering <olaf@xxxxxxxxx> wrote:
> # HG changeset patch
> # User Olaf Hering <olaf@xxxxxxxxx>
> # Date 1305037567 -7200
> # Node ID 7f6a118d237e60ca6f30723db687b06a8ef3c3e9
> # Parent 1a45e40add8b407532374c34f20bad51707808cf
> xentrace: allocate non-contiguous per-cpu trace buffers
>
> Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
>
> diff -r 1a45e40add8b -r 7f6a118d237e xen/common/trace.c
> --- a/xen/common/trace.c Tue May 10 16:25:39 2011 +0200
> +++ b/xen/common/trace.c Tue May 10 16:26:07 2011 +0200
> @@ -166,7 +166,7 @@ static int calculate_tbuf_size(unsigned
> */
> static int alloc_trace_bufs(unsigned int pages)
> {
> - int i, cpu, order;
> + int i, cpu;
> /* Start after a fixed-size array of NR_CPUS */
> uint32_t *t_info_mfn_list;
> uint16_t t_info_first_offset;
> @@ -182,34 +182,11 @@ static int alloc_trace_bufs(unsigned int
> t_info_first_offset = calc_tinfo_first_offset();
>
> pages = calculate_tbuf_size(pages, t_info_first_offset);
> - order = get_order_from_pages(pages);
>
> t_info = alloc_xenheap_pages(get_order_from_pages(t_info_pages), 0);
> if ( t_info == NULL )
> - goto out_dealloc;
> + goto out_dealloc_t_info;
>
> - /*
> - * First, allocate buffers for all of the cpus. If any
> - * fails, deallocate what you have so far and exit.
> - */
> - for_each_online_cpu(cpu)
> - {
> - void *rawbuf;
> - struct t_buf *buf;
> -
> - if ( (rawbuf = alloc_xenheap_pages(
> - order, MEMF_bits(32 + PAGE_SHIFT))) == NULL )
> - {
> - printk(XENLOG_INFO "xentrace: memory allocation failed "
> - "on cpu %d\n", cpu);
> - goto out_dealloc;
> - }
> -
> - per_cpu(t_bufs, cpu) = buf = rawbuf;
> - buf->cons = buf->prod = 0;
> - }
> -
> - offset = t_info_first_offset;
> t_info_mfn_list = (uint32_t *)t_info;
>
> for(i = 0; i < t_info_pages; i++)
> @@ -219,27 +196,53 @@ static int alloc_trace_bufs(unsigned int
> t_info->tbuf_size = pages;
>
> /*
> - * Now share the pages so xentrace can map them, and write them in
> - * the global t_info structure.
> + * Allocate buffers for all of the cpus.
> + * If any fails, deallocate what you have so far and exit.
> */
> for_each_online_cpu(cpu)
> {
> - void *rawbuf = per_cpu(t_bufs, cpu);
> - struct page_info *p = virt_to_page(rawbuf);
> - uint32_t mfn = virt_to_mfn(rawbuf);
> + offset = t_info_first_offset + (cpu * pages);
> + t_info->mfn_offset[cpu] = offset;
>
> for ( i = 0; i < pages; i++ )
> {
> - share_xen_page_with_privileged_guests(p + i, XENSHARE_writable);
> + void *p = alloc_xenheap_pages(0, MEMF_bits(32 + PAGE_SHIFT));
> + if ( !p )
> + {
> + printk(XENLOG_INFO "xentrace: memory allocation failed "
> + "on cpu %d after %d pages\n", cpu, i);
> + t_info_mfn_list[offset + i] = 0;
> + goto out_dealloc;
> + }
> + t_info_mfn_list[offset + i] = virt_to_mfn(p);
> + }
> + }
>
> - t_info_mfn_list[offset + i]=mfn + i;
> - }
> - t_info->mfn_offset[cpu]=offset;
> - printk(XENLOG_INFO "xentrace: p%d mfn %"PRIx32" offset %d\n",
> - cpu, mfn, offset);
> - offset+=i;
> + /*
> + * Initialize buffers for all of the cpus.
> + */
> + for_each_online_cpu(cpu)
> + {
> + struct t_buf *buf;
> + struct page_info *pg;
>
> spin_lock_init(&per_cpu(t_lock, cpu));
> +
> + offset = t_info->mfn_offset[cpu];
> +
> + /* Initialize the buffer metadata */
> + per_cpu(t_bufs, cpu) = buf = mfn_to_virt(t_info_mfn_list[offset]);
> + buf->cons = buf->prod = 0;
> +
> + printk(XENLOG_INFO "xentrace: p%d mfn %x offset %u\n",
> + cpu, t_info_mfn_list[offset], offset);
> +
> + /* Now share the trace pages */
> + for ( i = 0; i < pages; i++ )
> + {
> + pg = mfn_to_page(t_info_mfn_list[offset + i]);
> + share_xen_page_with_privileged_guests(pg, XENSHARE_writable);
> + }
> }
>
> data_size = (pages * PAGE_SIZE - sizeof(struct t_buf));
> @@ -255,14 +258,19 @@ static int alloc_trace_bufs(unsigned int
> out_dealloc:
> for_each_online_cpu(cpu)
> {
> - void *rawbuf = per_cpu(t_bufs, cpu);
> - per_cpu(t_bufs, cpu) = NULL;
> - if ( rawbuf )
> + offset = t_info->mfn_offset[cpu];
> + if ( !offset )
> + continue;
> + for ( i = 0; i < pages; i++ )
> {
> - ASSERT(!(virt_to_page(rawbuf)->count_info & PGC_allocated));
> - free_xenheap_pages(rawbuf, order);
> + uint32_t mfn = t_info_mfn_list[offset + i];
> + if ( !mfn )
> + break;
> + ASSERT(!(mfn_to_page(mfn)->count_info & PGC_allocated));
> + free_xenheap_pages(mfn_to_virt(mfn), 0);
> }
> }
> +out_dealloc_t_info:
> free_xenheap_pages(t_info, get_order_from_pages(t_info_pages));
> t_info = NULL;
> printk(XENLOG_WARNING "xentrace: allocation failed! Tracing disabled.\n");
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
>
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home