[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH v3 02/10] xen: reduce number of global variables in xen loader
On Fri, Feb 19, 2016 at 05:59:27AM +0100, Juergen Gross wrote: > On 18/02/16 18:00, Lennart Sorensen wrote: > > On Thu, Feb 18, 2016 at 11:34:49AM +0100, Juergen Gross wrote: > >> On 18/02/16 11:22, Daniel Kiper wrote: > >>> On Wed, Feb 17, 2016 at 06:19:29PM +0100, Juergen Gross wrote: > >>>> The loader for xen paravirtualized environment is using lots of global > >>>> variables. Reduce the number by making them either local or by putting > >>>> them into a single state structure. > >>>> > >>>> Signed-off-by: Juergen Gross <jgross@xxxxxxxx> > >>> > >>> Just two nitpicks but in general... > >>> > >>> Reviewed-by: Daniel Kiper <daniel.kiper@xxxxxxxxxx> > >>> > >>>> --- > >>>> grub-core/loader/i386/xen.c | 259 > >>>> +++++++++++++++++++++++--------------------- > >>>> 1 file changed, 138 insertions(+), 121 deletions(-) > >>>> > >>>> diff --git a/grub-core/loader/i386/xen.c b/grub-core/loader/i386/xen.c > >>>> index ff7c553..d5fe168 100644 > >>>> --- a/grub-core/loader/i386/xen.c > >>>> +++ b/grub-core/loader/i386/xen.c > >>>> @@ -42,16 +42,20 @@ > >>>> > >>>> GRUB_MOD_LICENSE ("GPLv3+"); > >>>> > >>>> -static struct grub_relocator *relocator = NULL; > >>>> -static grub_uint64_t max_addr; > >>>> +struct xen_loader_state { > >>>> + struct grub_relocator *relocator; > >>>> + struct start_info next_start; > >>>> + struct grub_xen_file_info xen_inf; > >>>> + grub_uint64_t max_addr; > >>>> + struct xen_multiboot_mod_list *module_info_page; > >>>> + grub_uint64_t modules_target_start; > >>>> + grub_size_t n_modules; > >>>> + int loaded; > >>>> +}; > >>>> + > >>>> +static struct xen_loader_state xen_state; > >>>> + > >>>> static grub_dl_t my_mod; > >>>> -static int loaded = 0; > >>>> -static struct start_info next_start; > >>>> -static void *kern_chunk_src; > >>>> -static struct grub_xen_file_info xen_inf; > >>>> -static struct xen_multiboot_mod_list *xen_module_info_page; > >>>> -static grub_uint64_t modules_target_start; > >>>> -static grub_size_t n_modules; > >>>> > >>>> #define PAGE_SIZE 4096 > >>>> #define MAX_MODULES (PAGE_SIZE / sizeof (struct xen_multiboot_mod_list)) > >>>> @@ -225,50 +229,55 @@ grub_xen_boot (void) > >>>> if (grub_xen_n_allocated_shared_pages) > >>>> return grub_error (GRUB_ERR_BUG, "active grants"); > >>>> > >>>> - state.mfn_list = max_addr; > >>>> - next_start.mfn_list = max_addr + xen_inf.virt_base; > >>>> - next_start.first_p2m_pfn = max_addr >> PAGE_SHIFT; /* Is this > >>>> right? */ > >>>> + state.mfn_list = xen_state.max_addr; > >>>> + xen_state.next_start.mfn_list = > >>>> + xen_state.max_addr + xen_state.xen_inf.virt_base; > >>>> + xen_state.next_start.first_p2m_pfn = xen_state.max_addr >> PAGE_SHIFT; > >>>> pgtsize = sizeof (grub_xen_mfn_t) * > >>>> grub_xen_start_page_addr->nr_pages; > >>>> - err = grub_relocator_alloc_chunk_addr (relocator, &ch, max_addr, > >>>> pgtsize); > >>>> - next_start.nr_p2m_frames = (pgtsize + PAGE_SIZE - 1) >> PAGE_SHIFT; > >>>> + err = grub_relocator_alloc_chunk_addr (xen_state.relocator, &ch, > >>>> + xen_state.max_addr, pgtsize); > >>>> + xen_state.next_start.nr_p2m_frames = (pgtsize + PAGE_SIZE - 1) >> > >>>> PAGE_SHIFT; > >>>> if (err) > >>>> return err; > >>>> new_mfn_list = get_virtual_current_address (ch); > >>>> grub_memcpy (new_mfn_list, > >>>> (void *) grub_xen_start_page_addr->mfn_list, pgtsize); > >>>> - max_addr = ALIGN_UP (max_addr + pgtsize, PAGE_SIZE); > >>>> + xen_state.max_addr = ALIGN_UP (xen_state.max_addr + pgtsize, > >>>> PAGE_SIZE); > >>>> > >>>> - err = grub_relocator_alloc_chunk_addr (relocator, &ch, > >>>> - max_addr, sizeof (next_start)); > >>>> + err = grub_relocator_alloc_chunk_addr (xen_state.relocator, &ch, > >>>> + xen_state.max_addr, > >>>> + sizeof (xen_state.next_start)); > >>>> if (err) > >>>> return err; > >>>> - state.start_info = max_addr + xen_inf.virt_base; > >>>> + state.start_info = xen_state.max_addr + xen_state.xen_inf.virt_base; > >>>> nst = get_virtual_current_address (ch); > >>>> - max_addr = ALIGN_UP (max_addr + sizeof (next_start), PAGE_SIZE); > >>>> + xen_state.max_addr = > >>>> + ALIGN_UP (xen_state.max_addr + sizeof (xen_state.next_start), > >>>> PAGE_SIZE); > >>>> > >>>> - next_start.nr_pages = grub_xen_start_page_addr->nr_pages; > >>>> - grub_memcpy (next_start.magic, grub_xen_start_page_addr->magic, > >>>> - sizeof (next_start.magic)); > >>>> - next_start.store_mfn = grub_xen_start_page_addr->store_mfn; > >>>> - next_start.store_evtchn = grub_xen_start_page_addr->store_evtchn; > >>>> - next_start.console.domU = grub_xen_start_page_addr->console.domU; > >>>> - next_start.shared_info = grub_xen_start_page_addr->shared_info; > >>>> + xen_state.next_start.nr_pages = grub_xen_start_page_addr->nr_pages; > >>>> + grub_memcpy (xen_state.next_start.magic, > >>>> grub_xen_start_page_addr->magic, > >>>> + sizeof (xen_state.next_start.magic)); > >>>> + xen_state.next_start.store_mfn = grub_xen_start_page_addr->store_mfn; > >>>> + xen_state.next_start.store_evtchn = > >>>> grub_xen_start_page_addr->store_evtchn; > >>>> + xen_state.next_start.console.domU = > >>>> grub_xen_start_page_addr->console.domU; > >>>> + xen_state.next_start.shared_info = > >>>> grub_xen_start_page_addr->shared_info; > >>>> > >>>> - err = set_mfns (new_mfn_list, max_addr >> PAGE_SHIFT); > >>>> + err = set_mfns (new_mfn_list, xen_state.max_addr >> PAGE_SHIFT); > >>>> if (err) > >>>> return err; > >>>> - max_addr += 2 * PAGE_SIZE; > >>>> + xen_state.max_addr += 2 * PAGE_SIZE; > >>>> > >>>> - next_start.pt_base = max_addr + xen_inf.virt_base; > >>>> - state.paging_start = max_addr >> PAGE_SHIFT; > >>>> + xen_state.next_start.pt_base = > >>>> + xen_state.max_addr + xen_state.xen_inf.virt_base; > >>>> + state.paging_start = xen_state.max_addr >> PAGE_SHIFT; > >>>> > >>>> - nr_info_pages = max_addr >> PAGE_SHIFT; > >>>> + nr_info_pages = xen_state.max_addr >> PAGE_SHIFT; > >>>> nr_pages = nr_info_pages; > >>>> > >>>> while (1) > >>>> { > >>>> nr_pages = ALIGN_UP (nr_pages, (ALIGN_SIZE >> PAGE_SHIFT)); > >>>> - nr_pt_pages = get_pgtable_size (nr_pages, xen_inf.virt_base); > >>>> + nr_pt_pages = get_pgtable_size (nr_pages, > >>>> xen_state.xen_inf.virt_base); > >>>> nr_need_pages = > >>>> nr_info_pages + nr_pt_pages + > >>>> ((ADDITIONAL_SIZE + STACK_SIZE) >> PAGE_SHIFT); > >>>> @@ -278,27 +287,28 @@ grub_xen_boot (void) > >>>> } > >>>> > >>>> grub_dprintf ("xen", "bootstrap domain %llx+%llx\n", > >>>> - (unsigned long long) xen_inf.virt_base, > >>>> + (unsigned long long) xen_state.xen_inf.virt_base, > >>>> (unsigned long long) page2offset (nr_pages)); > >>>> > >>>> - err = grub_relocator_alloc_chunk_addr (relocator, &ch, > >>>> - max_addr, page2offset > >>>> (nr_pt_pages)); > >>>> + err = grub_relocator_alloc_chunk_addr (xen_state.relocator, &ch, > >>>> + xen_state.max_addr, > >>>> + page2offset (nr_pt_pages)); > >>>> if (err) > >>>> return err; > >>>> > >>>> generate_page_table (get_virtual_current_address (ch), > >>>> - max_addr >> PAGE_SHIFT, nr_pages, > >>>> - xen_inf.virt_base, new_mfn_list); > >>>> + xen_state.max_addr >> PAGE_SHIFT, nr_pages, > >>>> + xen_state.xen_inf.virt_base, new_mfn_list); > >>>> > >>>> - max_addr += page2offset (nr_pt_pages); > >>>> - state.stack = max_addr + STACK_SIZE + xen_inf.virt_base; > >>>> - state.entry_point = xen_inf.entry_point; > >>>> + xen_state.max_addr += page2offset (nr_pt_pages); > >>>> + state.stack = xen_state.max_addr + STACK_SIZE + > >>>> xen_state.xen_inf.virt_base; > >>>> + state.entry_point = xen_state.xen_inf.entry_point; > >>>> > >>>> - next_start.nr_p2m_frames += nr_pt_pages; > >>>> - next_start.nr_pt_frames = nr_pt_pages; > >>>> + xen_state.next_start.nr_p2m_frames += nr_pt_pages; > >>>> + xen_state.next_start.nr_pt_frames = nr_pt_pages; > >>>> state.paging_size = nr_pt_pages; > >>>> > >>>> - *nst = next_start; > >>>> + *nst = xen_state.next_start; > >>>> > >>>> grub_memset (&gnttab_setver, 0, sizeof (gnttab_setver)); > >>>> > >>>> @@ -308,24 +318,20 @@ grub_xen_boot (void) > >>>> for (i = 0; i < ARRAY_SIZE (grub_xen_shared_info->evtchn_pending); > >>>> i++) > >>>> grub_xen_shared_info->evtchn_pending[i] = 0; > >>>> > >>>> - return grub_relocator_xen_boot (relocator, state, nr_pages, > >>>> - xen_inf.virt_base < > >>>> + return grub_relocator_xen_boot (xen_state.relocator, state, nr_pages, > >>>> + xen_state.xen_inf.virt_base < > >>>> PAGE_SIZE ? page2offset (nr_pages) : > >>>> 0, > >>>> nr_pages - 1, > >>>> page2offset (nr_pages - 1) + > >>>> - xen_inf.virt_base); > >>>> + xen_state.xen_inf.virt_base); > >>>> } > >>>> > >>>> static void > >>>> grub_xen_reset (void) > >>>> { > >>>> - grub_memset (&next_start, 0, sizeof (next_start)); > >>>> - xen_module_info_page = NULL; > >>>> - n_modules = 0; > >>>> + grub_relocator_unload (xen_state.relocator); > >>>> > >>>> - grub_relocator_unload (relocator); > >>>> - relocator = NULL; > >>>> - loaded = 0; > >>>> + grub_memset (&xen_state, 0, sizeof (xen_state)); > >>>> } > >>>> > >>>> static grub_err_t > >>>> @@ -409,17 +415,22 @@ grub_cmd_xen (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> grub_file_t file; > >>>> grub_elf_t elf; > >>>> grub_err_t err; > >>>> + void *kern_chunk_src; > >>>> + grub_relocator_chunk_t ch; > >>>> + grub_addr_t kern_start; > >>>> + grub_addr_t kern_end; > >>>> > >>>> if (argc == 0) > >>>> return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected")); > >>>> > >>>> + /* Call grub_loader_unset early to avoid it being called by > >>>> grub_loader_set */ > >>>> grub_loader_unset (); > >>>> > >>>> grub_xen_reset (); > >>>> > >>>> grub_create_loader_cmdline (argc - 1, argv + 1, > >>>> - (char *) next_start.cmd_line, > >>>> - sizeof (next_start.cmd_line) - 1); > >>>> + (char *) xen_state.next_start.cmd_line, > >>>> + sizeof (xen_state.next_start.cmd_line) - > >>>> 1); > >>>> > >>>> file = grub_file_open (argv[0]); > >>>> if (!file) > >>>> @@ -429,85 +440,82 @@ grub_cmd_xen (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> if (!elf) > >>>> goto fail; > >>>> > >>>> - err = grub_xen_get_info (elf, &xen_inf); > >>>> + err = grub_xen_get_info (elf, &xen_state.xen_inf); > >>>> if (err) > >>>> goto fail; > >>>> #ifdef __x86_64__ > >>>> - if (xen_inf.arch != GRUB_XEN_FILE_X86_64) > >>>> + if (xen_state.xen_inf.arch != GRUB_XEN_FILE_X86_64) > >>>> #else > >>>> - if (xen_inf.arch != GRUB_XEN_FILE_I386_PAE > >>>> - && xen_inf.arch != GRUB_XEN_FILE_I386_PAE_BIMODE) > >>>> + if (xen_state.xen_inf.arch != GRUB_XEN_FILE_I386_PAE > >>>> + && xen_state.xen_inf.arch != GRUB_XEN_FILE_I386_PAE_BIMODE) > >>>> #endif > >>>> { > >>>> grub_error (GRUB_ERR_BAD_OS, "incompatible architecture: %d", > >>>> - xen_inf.arch); > >>>> + xen_state.xen_inf.arch); > >>>> goto fail; > >>>> } > >>>> > >>>> - if (xen_inf.virt_base & (PAGE_SIZE - 1)) > >>>> + if (xen_state.xen_inf.virt_base & (PAGE_SIZE - 1)) > >>>> { > >>>> grub_error (GRUB_ERR_BAD_OS, "unaligned virt_base"); > >>>> goto fail; > >>>> } > >>>> grub_dprintf ("xen", "virt_base = %llx, entry = %llx\n", > >>>> - (unsigned long long) xen_inf.virt_base, > >>>> - (unsigned long long) xen_inf.entry_point); > >>>> + (unsigned long long) xen_state.xen_inf.virt_base, > >>>> + (unsigned long long) xen_state.xen_inf.entry_point); > >>>> > >>>> - relocator = grub_relocator_new (); > >>>> - if (!relocator) > >>>> + xen_state.relocator = grub_relocator_new (); > >>>> + if (!xen_state.relocator) > >>>> goto fail; > >>>> > >>>> - grub_relocator_chunk_t ch; > >>>> - grub_addr_t kern_start = xen_inf.kern_start - xen_inf.paddr_offset; > >>>> - grub_addr_t kern_end = xen_inf.kern_end - xen_inf.paddr_offset; > >>>> + kern_start = xen_state.xen_inf.kern_start - > >>>> xen_state.xen_inf.paddr_offset; > >>>> + kern_end = xen_state.xen_inf.kern_end - > >>>> xen_state.xen_inf.paddr_offset; > >>>> > >>>> - if (xen_inf.has_hypercall_page) > >>>> + if (xen_state.xen_inf.has_hypercall_page) > >>>> { > >>>> grub_dprintf ("xen", "hypercall page at 0x%llx\n", > >>>> - (unsigned long long) xen_inf.hypercall_page); > >>>> - if (xen_inf.hypercall_page - xen_inf.virt_base < kern_start) > >>>> - kern_start = xen_inf.hypercall_page - xen_inf.virt_base; > >>>> - > >>>> - if (xen_inf.hypercall_page - xen_inf.virt_base + PAGE_SIZE > > >>>> kern_end) > >>>> - kern_end = xen_inf.hypercall_page - xen_inf.virt_base + > >>>> PAGE_SIZE; > >>>> + (unsigned long long) > >>>> xen_state.xen_inf.hypercall_page); > >>>> + kern_start = grub_min (kern_start, > >>>> xen_state.xen_inf.hypercall_page - > >>>> + xen_state.xen_inf.virt_base); > >>>> + kern_end = grub_max (kern_end, xen_state.xen_inf.hypercall_page - > >>>> + xen_state.xen_inf.virt_base + > >>>> PAGE_SIZE); > >>>> } > >>>> > >>>> - max_addr = ALIGN_UP (kern_end, PAGE_SIZE); > >>>> + xen_state.max_addr = ALIGN_UP (kern_end, PAGE_SIZE); > >>>> > >>>> - err = grub_relocator_alloc_chunk_addr (relocator, &ch, kern_start, > >>>> + err = grub_relocator_alloc_chunk_addr (xen_state.relocator, &ch, > >>>> kern_start, > >>>> kern_end - kern_start); > >>>> if (err) > >>>> goto fail; > >>>> kern_chunk_src = get_virtual_current_address (ch); > >>>> > >>>> grub_dprintf ("xen", "paddr_offset = 0x%llx\n", > >>>> - (unsigned long long) xen_inf.paddr_offset); > >>>> + (unsigned long long) xen_state.xen_inf.paddr_offset); > >>>> grub_dprintf ("xen", "kern_start = 0x%llx, kern_end = 0x%llx\n", > >>>> - (unsigned long long) xen_inf.kern_start, > >>>> - (unsigned long long) xen_inf.kern_end); > >>>> + (unsigned long long) xen_state.xen_inf.kern_start, > >>>> + (unsigned long long) xen_state.xen_inf.kern_end); > >>>> > >>>> err = grub_elfXX_load (elf, argv[0], > >>>> (grub_uint8_t *) kern_chunk_src - kern_start > >>>> - - xen_inf.paddr_offset, 0, 0, 0); > >>>> + - xen_state.xen_inf.paddr_offset, 0, 0, 0); > >>>> > >>>> - if (xen_inf.has_hypercall_page) > >>>> + if (xen_state.xen_inf.has_hypercall_page) > >>>> { > >>>> unsigned i; > >>>> for (i = 0; i < PAGE_SIZE / HYPERCALL_INTERFACE_SIZE; i++) > >>>> set_hypercall_interface ((grub_uint8_t *) kern_chunk_src + > >>>> i * HYPERCALL_INTERFACE_SIZE + > >>>> - xen_inf.hypercall_page - > >>>> xen_inf.virt_base - > >>>> - kern_start, i); > >>>> + xen_state.xen_inf.hypercall_page - > >>>> + xen_state.xen_inf.virt_base - > >>>> kern_start, i); > >>>> } > >>>> > >>>> if (err) > >>>> goto fail; > >>>> > >>>> grub_dl_ref (my_mod); > >>>> - loaded = 1; > >>>> + xen_state.loaded = 1; > >>>> > >>>> grub_loader_set (grub_xen_boot, grub_xen_unload, 0); > >>>> - loaded = 1; > >>>> > >>>> goto fail; > >>>> > >>>> @@ -540,14 +548,14 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> goto fail; > >>>> } > >>>> > >>>> - if (!loaded) > >>>> + if (!xen_state.loaded) > >>>> { > >>>> grub_error (GRUB_ERR_BAD_ARGUMENT, > >>>> N_("you need to load the kernel first")); > >>>> goto fail; > >>>> } > >>>> > >>>> - if (next_start.mod_start || next_start.mod_len) > >>>> + if (xen_state.next_start.mod_start || xen_state.next_start.mod_len) > >>>> { > >>>> grub_error (GRUB_ERR_BAD_ARGUMENT, N_("initrd already loaded")); > >>>> goto fail; > >>>> @@ -560,7 +568,8 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> > >>>> if (size) > >>>> { > >>>> - err = grub_relocator_alloc_chunk_addr (relocator, &ch, max_addr, > >>>> size); > >>>> + err = grub_relocator_alloc_chunk_addr (xen_state.relocator, &ch, > >>>> + xen_state.max_addr, size); > >>>> if (err) > >>>> goto fail; > >>>> > >>>> @@ -569,13 +578,14 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> goto fail; > >>>> } > >>>> > >>>> - next_start.mod_start = max_addr + xen_inf.virt_base; > >>>> - next_start.mod_len = size; > >>>> + xen_state.next_start.mod_start = > >>>> + xen_state.max_addr + xen_state.xen_inf.virt_base; > >>>> + xen_state.next_start.mod_len = size; > >>>> > >>>> - max_addr = ALIGN_UP (max_addr + size, PAGE_SIZE); > >>>> + xen_state.max_addr = ALIGN_UP (xen_state.max_addr + size, PAGE_SIZE); > >>>> > >>>> grub_dprintf ("xen", "Initrd, addr=0x%x, size=0x%x\n", > >>>> - (unsigned) next_start.mod_start, (unsigned) size); > >>>> + (unsigned) xen_state.next_start.mod_start, (unsigned) > >>>> size); > >>>> > >>>> fail: > >>>> grub_initrd_close (&initrd_ctx); > >>>> @@ -607,45 +617,48 @@ grub_cmd_module (grub_command_t cmd __attribute__ > >>>> ((unused)), > >>>> if (argc == 0) > >>>> return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected")); > >>>> > >>>> - if (!loaded) > >>>> + if (!xen_state.loaded) > >>>> { > >>>> return grub_error (GRUB_ERR_BAD_ARGUMENT, > >>>> N_("you need to load the kernel first")); > >>>> } > >>>> > >>>> - if ((next_start.mod_start || next_start.mod_len) && > >>>> !xen_module_info_page) > >>>> + if ((xen_state.next_start.mod_start || xen_state.next_start.mod_len) > >>>> && > >>>> + !xen_state.module_info_page) > >>>> { > >>>> return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("initrd already > >>>> loaded")); > >>>> } > >>>> > >>>> /* Leave one space for terminator. */ > >>>> - if (n_modules >= MAX_MODULES - 1) > >>>> + if (xen_state.n_modules >= MAX_MODULES - 1) > >>>> { > >>>> return grub_error (GRUB_ERR_BAD_ARGUMENT, "too many modules"); > >>>> } > >>>> > >>>> - if (!xen_module_info_page) > >>>> + if (!xen_state.module_info_page) > >>>> { > >>>> - n_modules = 0; > >>>> - max_addr = ALIGN_UP (max_addr, PAGE_SIZE); > >>>> - modules_target_start = max_addr; > >>>> - next_start.mod_start = max_addr + xen_inf.virt_base; > >>>> - next_start.flags |= SIF_MULTIBOOT_MOD; > >>>> + xen_state.n_modules = 0; > >>>> + xen_state.max_addr = ALIGN_UP (xen_state.max_addr, PAGE_SIZE); > >>>> + xen_state.modules_target_start = xen_state.max_addr; > >>>> + xen_state.next_start.mod_start = > >>>> + xen_state.max_addr + xen_state.xen_inf.virt_base; Now that we have 8 characters worth of quoting and patch indentation, it looks perfect again. :) > >>> Lost one space. > >> > >> Really? Common indentation style seams to be to use tabs where possible. > >> And this is a tab. > > > > But your line continuation is indented LESS than the line it is > > continuing, which is clearly NOT the style. > > No. Tabs are 8 spaces and have been so in this file and in others as > well. Oh right. The horrible GNU coding style of 2 space indentation but tab replacing 8 spaces, which then gets messed up and looks weird when you start quoting it in email. It would be hard to come up with a worse indentation style than the GNU one. > BTW: any reason you omitted me from the to: and cc: list? I just hit reply-all, so no idea why it would have been dropped. -- Len Sorensen _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
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