Hi Nicholas, 2017-06-23 0:50 GMT+09:00 Nicholas Piggin <npiggin@xxxxxxxxx>: > On Thu, 22 Jun 2017 08:18:38 +0200 > Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote: > >> On Wed, Jun 21, 2017 at 10:55:06PM +0200, Arnd Bergmann wrote: >> > On Wed, Jun 21, 2017 at 8:08 PM, Nicholas Piggin <npiggin@xxxxxxxxx> wrote: >> > > On Wed, 21 Jun 2017 09:19:13 -0700 >> > > Stephen Boyd <sboyd@xxxxxxxxxxxxxx> wrote: >> > >> On 06/21, Arnd Bergmann wrote: >> > >> >> > >> Ok. Can you send a revert patch to the list with some information >> > >> on why we can't do the hack anymore and also Cc lkml/kbuild >> > >> lists? The commit is in linux-next now as commit 06e226c7fb23 >> > >> (clk: sunxi-ng: Move all clock types to a library, 2017-06-02). >> > >> >> > > >> > > I grabbed this patch and applied it to the kbuid/thin-ac tree. I tested >> > > with thin archives enabled and disabled with arm defconfig which ends up >> > > setting CONFIG_SUNXI_CCU=y. >> > > >> > > The patch makes no difference to vmlinux size whether using traditional >> > > incremental link, or thin archives (there is a small difference between >> > > inclink and thinarc but that's unrelated). >> > > >> > > So this thin archives change does not break your patch, it's just that >> > > it doesn't really do the right thing. I like the general idea, but we >> > > need to work out how to make it properly supported by the build system. >> > > >> > > With the patch applied, this is what the build system currently does: >> > > >> > > arm-linux-gnueabihf-ld -EL -r -o drivers/clk/sunxi-ng/built-in.o drivers/clk/sunxi-ng/ccu-sun5i.o drivers/clk/sunxi-ng/ccu-sun6i-a31.o drivers/clk/sunxi-ng/ccu-sun8i-a23.o drivers/clk/sunxi-ng/ccu-sun8i-a33.o drivers/clk/sunxi-ng/ccu-sun8i-h3.o drivers/clk/sunxi-ng/ccu-sun8i-v3s.o drivers/clk/sunxi-ng/ccu-sun8i-r.o drivers/clk/sunxi-ng/ccu-sun9i-a80.o drivers/clk/sunxi-ng/ccu-sun9i-a80-de.o drivers/clk/sunxi-ng/ccu-sun9i-a80-usb.o drivers/clk/sunxi-ng/lib.a drivers/clk/sunxi-ng/lib-ksyms.o >> > > >> > > This incremental link pulls in all your lib.a objects and links them >> > > into built-in.o. They can no longer be selectively linked. >> > >> > I think the ARM defconfig actually needs all those objects because it >> > enables all the high-level drivers. You could try disabling e.g. all except >> > CONFIG_SUN8I_DE2_CCU if you want the objects to actually becomes >> > unused. >> >> You can also disable MACH_SUN8I, it should disable a significant >> number of the clocks driver. > > text data bss dec hex filename > 11655078 6018736 418944 18092758 11412d6 vmlinux.inclink > 11655078 6018736 418944 18092758 11412d6 vmlinux.inclink.clk > 11650534 6010288 418616 18079438 113dece vmlinux.thinarc > 11650534 6010288 418616 18079438 113dece vmlinux.thinarc.clk > > Same result for me when compiling defconfig minus MACH_SUN8I, comparing > +/- the clock patch and thin archives. No size savings. As I explained > already, I really can't see how there could be any saving if the lib.a is > incrementally linked into built-in.o. I think defconfig minus MACH_SUN8I will give no difference to CONFIG_SUNXI_CCU* As far as I tried, minus MACH_SUN8I still enabled the following: CONFIG_SUNXI_CCU=y CONFIG_SUNXI_CCU_DIV=y CONFIG_SUNXI_CCU_FRAC=y CONFIG_SUNXI_CCU_GATE=y CONFIG_SUNXI_CCU_MUX=y CONFIG_SUNXI_CCU_MULT=y CONFIG_SUNXI_CCU_PHASE=y CONFIG_SUNXI_CCU_NK=y CONFIG_SUNXI_CCU_NKM=y CONFIG_SUNXI_CCU_NKMP=y CONFIG_SUNXI_CCU_NM=y CONFIG_SUNXI_CCU_MP=y I think you need to disable some more MACH_SUN*I and perhaps disable some CONFIG_SUN*I_*_CCU explicitly, then you will see difference in the result. -- Best Regards Masahiro Yamada
