[4/4] cc-swiotlb: Allow set swiotlb watermark from cmdline
Commit Message
Signed-off-by: GuoRui.Yu <GuoRui.Yu@linux.alibaba.com>
---
.../admin-guide/kernel-parameters.txt | 11 ++++++
kernel/dma/cc-swiotlb.c | 34 ++++++++++++++++++-
2 files changed, 44 insertions(+), 1 deletion(-)
Comments
Hi GuoRui.Yu",
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on tip/x86/core]
[also build test WARNING on joro-iommu/next driver-core/driver-core-testing driver-core/driver-core-next driver-core/driver-core-linus linus/master v6.2-rc5 next-20230127]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/GuoRui-Yu/swiotlb-Add-a-new-cc-swiotlb-implementation-for-Confidential-VMs/20230128-181154
patch link: https://lore.kernel.org/r/20230128083254.86012-5-GuoRui.Yu%40linux.alibaba.com
patch subject: [PATCH 4/4] cc-swiotlb: Allow set swiotlb watermark from cmdline
config: nios2-buildonly-randconfig-r002-20230129 (https://download.01.org/0day-ci/archive/20230129/202301290417.n1KMDPQt-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/fcbd538c875f5f1086682829671935d7155e4029
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review GuoRui-Yu/swiotlb-Add-a-new-cc-swiotlb-implementation-for-Confidential-VMs/20230128-181154
git checkout fcbd538c875f5f1086682829671935d7155e4029
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=nios2 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=nios2 SHELL=/bin/bash kernel/dma/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
kernel/dma/cc-swiotlb.c: In function 'swiotlb_bounce':
kernel/dma/cc-swiotlb.c:200:32: warning: variable 'tlb_end' set but not used [-Wunused-but-set-variable]
200 | phys_addr_t orig_addr, tlb_end, slot_start, slot_end = tlb_addr ;
| ^~~~~~~
In file included from kernel/dma/cc-swiotlb.c:13:
kernel/dma/cc-swiotlb.c: In function 'cc_populate_pages':
>> include/linux/kern_levels.h:5:25: warning: format '%lu' expects argument of type 'long unsigned int', but argument 2 has type 'size_t' {aka 'unsigned int'} [-Wformat=]
5 | #define KERN_SOH "\001" /* ASCII Start Of Header */
| ^~~~~~
include/linux/printk.h:429:25: note: in definition of macro 'printk_index_wrap'
429 | _p_func(_fmt, ##__VA_ARGS__); \
| ^~~~
include/linux/printk.h:530:9: note: in expansion of macro 'printk'
530 | printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~
include/linux/kern_levels.h:14:25: note: in expansion of macro 'KERN_SOH'
14 | #define KERN_INFO KERN_SOH "6" /* informational */
| ^~~~~~~~
include/linux/printk.h:530:16: note: in expansion of macro 'KERN_INFO'
530 | printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~~~
kernel/dma/cc-swiotlb.c:411:9: note: in expansion of macro 'pr_info'
411 | pr_info("bounce buffer size adjusted to %luMB", size >> 20);
| ^~~~~~~
kernel/dma/cc-swiotlb.c: At top level:
kernel/dma/cc-swiotlb.c:524:13: warning: no previous prototype for 'swiotlb_hint_cpus' [-Wmissing-prototypes]
524 | void __init swiotlb_hint_cpus(int cpus) {}
| ^~~~~~~~~~~~~~~~~
vim +5 include/linux/kern_levels.h
314ba3520e513a Joe Perches 2012-07-30 4
04d2c8c83d0e3a Joe Perches 2012-07-30 @5 #define KERN_SOH "\001" /* ASCII Start Of Header */
04d2c8c83d0e3a Joe Perches 2012-07-30 6 #define KERN_SOH_ASCII '\001'
04d2c8c83d0e3a Joe Perches 2012-07-30 7
@@ -6090,6 +6090,17 @@
wouldn't be automatically used by the kernel
noforce -- Never use bounce buffers (for debugging)
+ cc_swiotlb= [X86]
+ Format: { [<int>, <int>, <int>, <int>]| force ]}
+ Set the swiotlb TLB buffer initial size for Confidential Computing like
+ TDX and SEV-SNP.
+ <int> -- Number of I/O TLB of 256 bytes
+ <int> -- Number of I/O TLB of 4 KiB
+ <int> -- Number of I/O TLB of 64 KiB
+ <int> -- Number of I/O TLB of 256 KiB
+ force -- force using of cc bounce buffers even if they
+ wouldn't be automatically used by the kernel (for debugging)
+
switches= [HW,M68k]
sysctl.*= [KNL]
@@ -52,6 +52,32 @@ enum SLOT_SIZE {
const unsigned int SLOT_SIZES[NR_OF_SIZES] = {512, 2048, 4096, 16 * 1024, 512 * 1024};
unsigned int WATERMARK_SLOT_SIZE[NR_OF_SIZES] = {256, 16384, 8192, 1024, 32};
+static bool swiotlb_force_bounce = false;
+
+static int __init
+setup_io_tlb_watermark(char *str)
+{
+ int i;
+ size_t size;
+
+ for (i = 0; i < NR_OF_SIZES; i++) {
+ if (isdigit(*str)) {
+ size = simple_strtoul(str, &str, 0);
+ WATERMARK_SLOT_SIZE[i] = size;
+
+ if (*str == ',')
+ ++str;
+ }
+ else
+ break;
+ }
+
+ if (!strcmp(str, "force"))
+ swiotlb_force_bounce = true;
+
+ return 0;
+}
+early_param("cc_swiotlb", setup_io_tlb_watermark);
struct slot_terrace {
struct list_head slots_by_size[NR_OF_SIZES];
@@ -330,6 +356,7 @@ static void cc_populate_pages(void)
size_t i, j, k;
const size_t max_bytes_per_alloc = (MAX_ORDER_NR_PAGES << PAGE_SHIFT);
size_t remain_alloc_size, rounds, round_size, round_slot_nr;
+ size_t size = 0;
for (i = 0; i < NR_OF_SIZES; i++) {
if (atomic_read(&terrace.free_count_by_size[i]) > WATERMARK_SLOT_SIZE[i])
@@ -377,6 +404,11 @@ static void cc_populate_pages(void)
spin_unlock_irqrestore(&terrace.lock_by_size[i], flags);
}
}
+
+ for (i = 0; i < NR_OF_SIZES; i++) {
+ size += (size_t)atomic_read(&terrace.total_count_by_size[i]) * SLOT_SIZES[i];
+ }
+ pr_info("bounce buffer size adjusted to %luMB", size >> 20);
}
static int kccd(void *p)
@@ -437,7 +469,7 @@ void __init swiotlb_init(bool addressing_limit, unsigned int flags)
return;
}
- io_tlb_default_mem.force_bounce = cc_platform_has(CC_ATTR_MEM_ENCRYPT);
+ io_tlb_default_mem.force_bounce = cc_platform_has(CC_ATTR_MEM_ENCRYPT) || swiotlb_force_bounce;
xa_init_flags(io_tlb_default_mem.mapping, 0);