Commit 7944c724 authored by Kefeng Wang's avatar Kefeng Wang Committed by Liu Shixin
Browse files

tmpfs: fault in smaller chunks if large folio allocation not allowed 

hulk inclusion
category: performance
bugzilla: https://gitee.com/openeuler/kernel/issues/IAO6NS



--------------------------------

The tmpfs supports large folio, but there is some configurable options
to enable/disable large folio allocation, and for huge=within_size,
large folio only allowabled if it fully within i_size, so there is
performance issue when perform write without large folio, it is very
similar with commit 4e527d5841e2 ("iomap: fault in smaller chunks for
non-large folio mappings"),

Fix it by checking whether it allows large folio allocation or not
before perform write.

Fixes: 9aac777aaf94 ("filemap: Convert generic_perform_write() to support large folios")
Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent 898fad02

include/linux/fs.h

+2 −0
Original line number Diff line number Diff line
@@ -372,6 +372,8 @@ enum rw_hint { 
#define IOCB_DIO_CALLER_COMP	(1 << 22)

/* kiocb is a read or write operation submitted by fs/aio.c. */

#define IOCB_AIO_RW		(1 << 23)

/* fault int small chunks(PAGE_SIZE) from userspace */

#define IOCB_NO_LARGE_CHUNK	(1 << 24)



/* for use in trace events */

#define TRACE_IOCB_STRINGS \

mm/filemap.c

+6 −1
Original line number Diff line number Diff line
@@ -4043,9 +4043,14 @@ ssize_t generic_perform_write(struct kiocb *iocb, struct iov_iter *i) 
	loff_t pos = iocb->ki_pos;

	struct address_space *mapping = file->f_mapping;

	const struct address_space_operations *a_ops = mapping->a_ops;

	size_t chunk = mapping_max_folio_size(mapping);

	long status = 0;

	ssize_t written = 0;

	size_t chunk;



	if (iocb->ki_flags & IOCB_NO_LARGE_CHUNK)

		chunk = PAGE_SIZE;

	else

		chunk = mapping_max_folio_size(mapping);



	do {

		struct page *page;

mm/shmem.c

+5 −0
Original line number Diff line number Diff line
@@ -3042,6 +3042,7 @@ static ssize_t shmem_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
{

	struct file *file = iocb->ki_filp;

	struct inode *inode = file->f_mapping->host;

	pgoff_t index = iocb->ki_pos >> PAGE_SHIFT;

	ssize_t ret;



	inode_lock(inode);
@@ -3054,6 +3055,10 @@ static ssize_t shmem_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
	ret = file_update_time(file);

	if (ret)

		goto unlock;



	if (!shmem_allowable_huge_orders(inode, NULL, index, 0, false))

		iocb->ki_flags |= IOCB_NO_LARGE_CHUNK;



	ret = generic_perform_write(iocb, from);

unlock:

	inode_unlock(inode);