mirror of https://gitee.com/openkylin/linux.git
648eee52cc
Add a little strncpy optimization which can easily cut boot time by 20%. When the kernel is booting with initramfs, it builds up the filesystem from a cpio archive by calling strncpy_from_user() via fs/namei.c's do_getname() on every file in the archive (which can be lots) with a length of PATH_MAX (1024). This causes the dest of the strncpy to be padded with many NUL bytes. This optimization mostly causes these NUL bytes to be padded with a call to memset() which is already optimized for filling memory quickly, but the hardware loop helps a little bit as well. Boot time measured with 'loglevel=0' so UART speed doesn't get in the way. Signed-off-by: Robin Getz <robin.getz@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> |
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| .. | ||
| Makefile | ||
| ashldi3.c | ||
| ashrdi3.c | ||
| divsi3.S | ||
| gcclib.h | ||
| ins.S | ||
| lshrdi3.c | ||
| memchr.S | ||
| memcmp.S | ||
| memcpy.S | ||
| memmove.S | ||
| memset.S | ||
| modsi3.S | ||
| muldi3.S | ||
| outs.S | ||
| smulsi3_highpart.S | ||
| strcmp.S | ||
| strcpy.S | ||
| strncmp.S | ||
| strncpy.S | ||
| udivsi3.S | ||
| umodsi3.S | ||
| umulsi3_highpart.S | ||