| Message ID | 20190423224748.3765-4-fancer.lancer@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | mips: Post-bootmem-memblock transition fixes | expand |
Hello, Serge Semin wrote: > Before bootmem was completely removed from the kernel, the last loop > in the bootmem_init() had been used to reserve the correspondingly > marked regions, initialize sparsemem sections and to free the low memory > pages, which then would be used for early memory allocations. After the > bootmem removing patchset had been merged the loop was left to do the first > two things only. But it didn't do them quite well. > > First of all it leaves the BOOT_MEM_INIT_RAM memory types unreserved, > which is definitely bug (although it isn't noticeable due to being used > by the kernel region only, which is fully marked as reserved). Secondly > the reservation is supposed to be done for any memory including the > high one. (I couldn't figure out why the highmem was ignored in the first > place, since platforms and dts' may declare any memory region for > reservation) Thirdly the reserved_end variable had been used here to not > accidentally free memory occupied by kernel. Since we already reserved the > corresponding region higher in this method there is no need in using the > variable here anymore. Fourthly the sparsemem should be aware of all the > memory types in the system including the ROM_DATA even if it is going to > be reserved for the whole system uptime. Finally after all these notes are > fixed the loop of memory reservation can be freely merged into the memory > installation loop as it's done in this patch. > > Signed-off-by: Serge Semin <fancer.lancer@gmail.com> Applied to mips-next. Thanks, Paul [ This message was auto-generated; if you believe anything is incorrect then please email paul.burton@mips.com to report it. ]
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 53d93a727d1a..185e0e42e009 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -483,55 +483,21 @@ static void __init bootmem_init(void) continue; memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0); - } - - /* - * Register fully available low RAM pages with the bootmem allocator. - */ - for (i = 0; i < boot_mem_map.nr_map; i++) { - unsigned long start, end, size; - - start = PFN_UP(boot_mem_map.map[i].addr); - end = PFN_DOWN(boot_mem_map.map[i].addr - + boot_mem_map.map[i].size); - /* - * Reserve usable memory. - */ + /* Reserve any memory except the ordinary RAM ranges. */ switch (boot_mem_map.map[i].type) { case BOOT_MEM_RAM: break; - case BOOT_MEM_INIT_RAM: - memory_present(0, start, end); - continue; - default: - /* Not usable memory */ - if (start > min_low_pfn && end < max_low_pfn) - memblock_reserve(boot_mem_map.map[i].addr, - boot_mem_map.map[i].size); - - continue; + default: /* Reserve the rest of the memory types at boot time */ + memblock_reserve(PFN_PHYS(start), PFN_PHYS(end - start)); + break; } /* - * We are rounding up the start address of usable memory - * and at the end of the usable range downwards. - */ - if (start >= max_low_pfn) - continue; - if (start < reserved_end) - start = reserved_end; - if (end > max_low_pfn) - end = max_low_pfn; - - /* - * ... finally, is the area going away? + * In any case the added to the memblock memory regions + * (highmem/lowmem, available/reserved, etc) are considered + * as present, so inform sparsemem about them. */ - if (end <= start) - continue; - size = end - start; - - /* Register lowmem ranges */ memory_present(0, start, end); }
Before bootmem was completely removed from the kernel, the last loop in the bootmem_init() had been used to reserve the correspondingly marked regions, initialize sparsemem sections and to free the low memory pages, which then would be used for early memory allocations. After the bootmem removing patchset had been merged the loop was left to do the first two things only. But it didn't do them quite well. First of all it leaves the BOOT_MEM_INIT_RAM memory types unreserved, which is definitely bug (although it isn't noticeable due to being used by the kernel region only, which is fully marked as reserved). Secondly the reservation is supposed to be done for any memory including the high one. (I couldn't figure out why the highmem was ignored in the first place, since platforms and dts' may declare any memory region for reservation) Thirdly the reserved_end variable had been used here to not accidentally free memory occupied by kernel. Since we already reserved the corresponding region higher in this method there is no need in using the variable here anymore. Fourthly the sparsemem should be aware of all the memory types in the system including the ROM_DATA even if it is going to be reserved for the whole system uptime. Finally after all these notes are fixed the loop of memory reservation can be freely merged into the memory installation loop as it's done in this patch. Signed-off-by: Serge Semin <fancer.lancer@gmail.com> --- arch/mips/kernel/setup.c | 48 ++++++---------------------------------- 1 file changed, 7 insertions(+), 41 deletions(-)