jfs: microoptimize get_zeroed_page / virt_to_page (76e8d7cb) · Commits · 戴 / test

get_zeroed_page does alloc_page and returns page_address of the result; subsequent virt_to_page will recover the page, but since the caller needs both page and its page_address() anyway, why bother going through that wrapper at all? Signed-off-by:

Al Viro <viro@zeniv.linux.org.uk>

fs/jfs/jfs_logmgr.c

+4 −5

Original line number	Diff line number	Diff line
		@@ -1835,17 +1835,16 @@ static int lbmLogInit(struct jfs_log * log)
		for (i = 0; i < LOGPAGES;) {
		char *buffer;
		uint offset;
		struct page *page;
		struct page *page = alloc_page(GFP_KERNEL \| __GFP_ZERO);

		buffer = (char *) get_zeroed_page(GFP_KERNEL);
		if (buffer == NULL)
		if (!page)
		goto error;
		page = virt_to_page(buffer);
		buffer = page_address(page);
		for (offset = 0; offset < PAGE_SIZE; offset += LOGPSIZE) {
		lbuf = kmalloc(sizeof(struct lbuf), GFP_KERNEL);
		if (lbuf == NULL) {
		if (offset == 0)
		free_page((unsigned long) buffer);
		__free_page(page);
		goto error;
		}
		if (offset) /* we already have one reference */

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