| Message ID | d408a1b35307101e82a6845e26af4a122c8e5a25.1721363035.git.wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: try to allocate larger folios for metadata | expand |
On Fri 19-07-24 14:19:05, Qu Wenruo wrote: [...] > @@ -2981,8 +2982,17 @@ static int attach_eb_folio_to_filemap(struct extent_buffer *eb, int i, > ASSERT(eb->folios[i]); > > retry: > + /* > + * Btree inode is a btrfs internal inode, and not exposed to any > + * user. > + * Furthermore we do not want any cgroup limits on this inode. > + * So we always use root_mem_cgroup as our active memcg when attaching > + * the folios. > + */ > + old_memcg = set_active_memcg(root_mem_cgroup); > ret = filemap_add_folio(mapping, eb->folios[i], index + i, > GFP_NOFS | __GFP_NOFAIL); > + set_active_memcg(old_memcg); I do not think this will compile with CONFIG_MEMCG=n > if (!ret) > goto finish; > > -- > 2.45.2
在 2024/7/19 16:38, Michal Hocko 写道: > On Fri 19-07-24 14:19:05, Qu Wenruo wrote: > [...] >> @@ -2981,8 +2982,17 @@ static int attach_eb_folio_to_filemap(struct extent_buffer *eb, int i, >> ASSERT(eb->folios[i]); >> >> retry: >> + /* >> + * Btree inode is a btrfs internal inode, and not exposed to any >> + * user. >> + * Furthermore we do not want any cgroup limits on this inode. >> + * So we always use root_mem_cgroup as our active memcg when attaching >> + * the folios. >> + */ >> + old_memcg = set_active_memcg(root_mem_cgroup); >> ret = filemap_add_folio(mapping, eb->folios[i], index + i, >> GFP_NOFS | __GFP_NOFAIL); >> + set_active_memcg(old_memcg); > > I do not think this will compile with CONFIG_MEMCG=n My bad. I'll fix it from the btrfs part so that @root_mem_cgroup would be changed to NULL for the CONFIG_MEMCG=n case. Meanwhile, can we just define root_mem_cgroup as NULL globally? That looks more reasonable to me, and if that's fine I can send out an extra patch just for that. Thanks, Qu > >> if (!ret) >> goto finish; >> >> -- >> 2.45.2 >
在 2024/7/19 16:46, Qu Wenruo 写道: > > > 在 2024/7/19 16:38, Michal Hocko 写道: >> On Fri 19-07-24 14:19:05, Qu Wenruo wrote: >> [...] >>> @@ -2981,8 +2982,17 @@ static int attach_eb_folio_to_filemap(struct >>> extent_buffer *eb, int i, >>> ASSERT(eb->folios[i]); >>> >>> retry: >>> + /* >>> + * Btree inode is a btrfs internal inode, and not exposed to any >>> + * user. >>> + * Furthermore we do not want any cgroup limits on this inode. >>> + * So we always use root_mem_cgroup as our active memcg when >>> attaching >>> + * the folios. >>> + */ >>> + old_memcg = set_active_memcg(root_mem_cgroup); >>> ret = filemap_add_folio(mapping, eb->folios[i], index + i, >>> GFP_NOFS | __GFP_NOFAIL); >>> + set_active_memcg(old_memcg); >> >> I do not think this will compile with CONFIG_MEMCG=n > > My bad. > > I'll fix it from the btrfs part so that @root_mem_cgroup would be > changed to NULL for the CONFIG_MEMCG=n case. > > Meanwhile, can we just define root_mem_cgroup as NULL globally? Of course, I mean for the CONFIG_MEMCG=n case. Thanks, Qu > That looks more reasonable to me, and if that's fine I can send out an > extra patch just for that. > > Thanks, > Qu > >> >>> if (!ret) >>> goto finish; >>> >>> -- >>> 2.45.2 >>
On Fri 19-07-24 16:46:50, Qu Wenruo wrote: > Meanwhile, can we just define root_mem_cgroup as NULL globally? > That looks more reasonable to me, and if that's fine I can send out an > extra patch just for that. I think it would be sufficient to pull root_mem_cgroup declaration out of ifdef in memcontrol.h. We do not really have to define it. Please send the patch and add all memcg maintainers. Ideally with this patch in the series so that the intention is clear.
Hi Qu,
kernel test robot noticed the following build errors:
[auto build test ERROR on kdave/for-next]
[also build test ERROR on linus/master v6.10 next-20240719]
[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/Qu-Wenruo/btrfs-always-uses-root-memcgroup-for-filemap_add_folio/20240719-125131
base: https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
patch link: https://lore.kernel.org/r/d408a1b35307101e82a6845e26af4a122c8e5a25.1721363035.git.wqu%40suse.com
patch subject: [PATCH v5 1/2] btrfs: always uses root memcgroup for filemap_add_folio()
config: sh-allmodconfig (https://download.01.org/0day-ci/archive/20240719/202407192308.yzjpnura-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240719/202407192308.yzjpnura-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407192308.yzjpnura-lkp@intel.com/
All errors (new ones prefixed by >>, old ones prefixed by <<):
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-samsung.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-semitek.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-sjoy.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-sony.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-speedlink.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-steam.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-steelseries.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-sunplus.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-gaff.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-tmff.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-tivo.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-topseed.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-twinhan.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-uclogic.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-xinmo.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-zpff.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-zydacron.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-viewsonic.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-waltop.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hid/hid-winwing.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/fbtft/fbtft.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-bootrom.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-spilib.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-hid.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-light.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-log.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-loopback.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-power-supply.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-raw.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-vibrator.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-audio-manager.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-gbphy.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-gpio.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-i2c.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-pwm.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-sdio.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-spi.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-uart.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/staging/greybus/gb-usb.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/platform/chrome/cros_kunit_proto_test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mailbox/mtk-cmdq-mailbox.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/devfreq/governor_simpleondemand.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/devfreq/governor_performance.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/devfreq/governor_powersave.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/devfreq/governor_userspace.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/perf/arm-ccn.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/perf/fsl_imx8_ddr_perf.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/perf/arm_cspmu/arm_cspmu_module.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/perf/arm_cspmu/nvidia_cspmu.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/perf/arm_cspmu/ampere_cspmu.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/nvmem/nvmem-apple-efuses.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/nvmem/nvmem_brcm_nvram.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/nvmem/nvmem_u-boot-env.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/interconnect/imx/imx-interconnect.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/interconnect/imx/imx8mm-interconnect.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/interconnect/imx/imx8mq-interconnect.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/interconnect/imx/imx8mn-interconnect.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/interconnect/imx/imx8mp-interconnect.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hte/hte-tegra194-test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/vdpa/vdpa.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/parport/parport.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mtd/parsers/brcm_u-boot.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mtd/parsers/tplink_safeloader.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mtd/chips/cfi_util.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mtd/chips/cfi_cmdset_0020.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/mtd/maps/map_funcs.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spmi/hisi-spmi-controller.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spmi/spmi-pmic-arb.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pcmcia/pcmcia_rsrc.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hwmon/corsair-cpro.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/hwmon/mr75203.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/greybus/greybus.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/greybus/gb-es2.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rpmsg/rpmsg_char.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/iio/adc/ingenic-adc.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/iio/adc/xilinx-ams.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/iio/buffer/kfifo_buf.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-core.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-master-hub.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-master-aspeed.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-master-gpio.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-master-ast-cf.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/fsi/fsi-scom.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/siox/siox-bus-gpio.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/counter/ftm-quaddec.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/vfio-mdev/mtty.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/vfio-mdev/mdpy.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/vfio-mdev/mdpy-fb.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/vfio-mdev/mbochs.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/configfs/configfs_sample.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/bytestream-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/dma-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/inttype-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/record-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kobject/kobject-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kobject/kset-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kprobes/kprobe_example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kprobes/kretprobe_example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kmemleak/kmemleak-test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/sh/drivers/push-switch.o
>> ERROR: modpost: "root_mem_cgroup" [fs/btrfs/btrfs.ko] undefined!
ERROR: modpost: "__delay" [drivers/net/mdio/mdio-cavium.ko] undefined!
ERROR: modpost: "devm_of_clk_add_hw_provider" [drivers/media/i2c/tc358746.ko] undefined!
ERROR: modpost: "devm_clk_hw_register" [drivers/media/i2c/tc358746.ko] undefined!
ERROR: modpost: "of_clk_hw_simple_get" [drivers/media/i2c/tc358746.ko] undefined!
Hi Qu, kernel test robot noticed the following build errors: [auto build test ERROR on kdave/for-next] [also build test ERROR on linus/master v6.10 next-20240719] [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/Qu-Wenruo/btrfs-always-uses-root-memcgroup-for-filemap_add_folio/20240719-125131 base: https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next patch link: https://lore.kernel.org/r/d408a1b35307101e82a6845e26af4a122c8e5a25.1721363035.git.wqu%40suse.com patch subject: [PATCH v5 1/2] btrfs: always uses root memcgroup for filemap_add_folio() config: x86_64-buildonly-randconfig-002-20240719 (https://download.01.org/0day-ci/archive/20240719/202407192346.BjAEmrYl-lkp@intel.com/config) compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240719/202407192346.BjAEmrYl-lkp@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202407192346.BjAEmrYl-lkp@intel.com/ All errors (new ones prefixed by >>): >> fs/btrfs/extent_io.c:2992:31: error: use of undeclared identifier 'root_mem_cgroup'; did you mean 'parent_mem_cgroup'? 2992 | old_memcg = set_active_memcg(root_mem_cgroup); | ^~~~~~~~~~~~~~~ | parent_mem_cgroup include/linux/memcontrol.h:1288:34: note: 'parent_mem_cgroup' declared here 1288 | static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) | ^ 1 error generated. vim +2992 fs/btrfs/extent_io.c 2971 2972 struct btrfs_fs_info *fs_info = eb->fs_info; 2973 struct address_space *mapping = fs_info->btree_inode->i_mapping; 2974 struct mem_cgroup *old_memcg; 2975 const unsigned long index = eb->start >> PAGE_SHIFT; 2976 struct folio *existing_folio = NULL; 2977 int ret; 2978 2979 ASSERT(found_eb_ret); 2980 2981 /* Caller should ensure the folio exists. */ 2982 ASSERT(eb->folios[i]); 2983 2984 retry: 2985 /* 2986 * Btree inode is a btrfs internal inode, and not exposed to any 2987 * user. 2988 * Furthermore we do not want any cgroup limits on this inode. 2989 * So we always use root_mem_cgroup as our active memcg when attaching 2990 * the folios. 2991 */ > 2992 old_memcg = set_active_memcg(root_mem_cgroup); 2993 ret = filemap_add_folio(mapping, eb->folios[i], index + i, 2994 GFP_NOFS | __GFP_NOFAIL); 2995 set_active_memcg(old_memcg); 2996 if (!ret) 2997 goto finish; 2998 2999 existing_folio = filemap_lock_folio(mapping, index + i); 3000 /* The page cache only exists for a very short time, just retry. */ 3001 if (IS_ERR(existing_folio)) { 3002 existing_folio = NULL; 3003 goto retry; 3004 } 3005 3006 /* For now, we should only have single-page folios for btree inode. */ 3007 ASSERT(folio_nr_pages(existing_folio) == 1); 3008 3009 if (folio_size(existing_folio) != eb->folio_size) { 3010 folio_unlock(existing_folio); 3011 folio_put(existing_folio); 3012 return -EAGAIN; 3013 } 3014 3015 finish: 3016 spin_lock(&mapping->i_private_lock); 3017 if (existing_folio && fs_info->nodesize < PAGE_SIZE) { 3018 /* We're going to reuse the existing page, can drop our folio now. */ 3019 __free_page(folio_page(eb->folios[i], 0)); 3020 eb->folios[i] = existing_folio; 3021 } else if (existing_folio) { 3022 struct extent_buffer *existing_eb; 3023 3024 existing_eb = grab_extent_buffer(fs_info, 3025 folio_page(existing_folio, 0)); 3026 if (existing_eb) { 3027 /* The extent buffer still exists, we can use it directly. */ 3028 *found_eb_ret = existing_eb; 3029 spin_unlock(&mapping->i_private_lock); 3030 folio_unlock(existing_folio); 3031 folio_put(existing_folio); 3032 return 1; 3033 } 3034 /* The extent buffer no longer exists, we can reuse the folio. */ 3035 __free_page(folio_page(eb->folios[i], 0)); 3036 eb->folios[i] = existing_folio; 3037 } 3038 eb->folio_size = folio_size(eb->folios[i]); 3039 eb->folio_shift = folio_shift(eb->folios[i]); 3040 /* Should not fail, as we have preallocated the memory. */ 3041 ret = attach_extent_buffer_folio(eb, eb->folios[i], prealloc); 3042 ASSERT(!ret); 3043 /* 3044 * To inform we have an extra eb under allocation, so that 3045 * detach_extent_buffer_page() won't release the folio private when the 3046 * eb hasn't been inserted into radix tree yet. 3047 * 3048 * The ref will be decreased when the eb releases the page, in 3049 * detach_extent_buffer_page(). Thus needs no special handling in the 3050 * error path. 3051 */ 3052 btrfs_folio_inc_eb_refs(fs_info, eb->folios[i]); 3053 spin_unlock(&mapping->i_private_lock); 3054 return 0; 3055 } 3056
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index aa7f8148cd0d..cfeed7673009 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2971,6 +2971,7 @@ static int attach_eb_folio_to_filemap(struct extent_buffer *eb, int i, struct btrfs_fs_info *fs_info = eb->fs_info; struct address_space *mapping = fs_info->btree_inode->i_mapping; + struct mem_cgroup *old_memcg; const unsigned long index = eb->start >> PAGE_SHIFT; struct folio *existing_folio = NULL; int ret; @@ -2981,8 +2982,17 @@ static int attach_eb_folio_to_filemap(struct extent_buffer *eb, int i, ASSERT(eb->folios[i]); retry: + /* + * Btree inode is a btrfs internal inode, and not exposed to any + * user. + * Furthermore we do not want any cgroup limits on this inode. + * So we always use root_mem_cgroup as our active memcg when attaching + * the folios. + */ + old_memcg = set_active_memcg(root_mem_cgroup); ret = filemap_add_folio(mapping, eb->folios[i], index + i, GFP_NOFS | __GFP_NOFAIL); + set_active_memcg(old_memcg); if (!ret) goto finish;
The function filemap_add_folio() would also charge the memory cgroup, as all filemap folios are controlled by memory cgroup. This also means, if there is some memory cgroup set, we're only relying on the __GFP_NOFAIL flag to prevent mem cgroup to return -ENOMEM. However this is not really that suitable for btrfs btree inode, as the btree inode is not accessible out of btrfs module, and we do not want the memory limits on this critical part of btrfs metadata allocation. So here we just manually set the active memory cgroup to the root one, which has no memory limits or whatever, before calling filemap_add_folio(), then restore to the old memcgroup. By this we avoid the unnecessary memory limits and can later remove the __GFP_NOFAIL usage. Suggested-by: Michal Hocko <mhocko@suse.com> Suggested-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/extent_io.c | 10 ++++++++++ 1 file changed, 10 insertions(+)