* Rebuild a changed kernel quickly with make?
@ 2013-07-04 6:33 Martin Kepplinger
2013-07-04 6:53 ` Warlich, Christof
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Martin Kepplinger @ 2013-07-04 6:33 UTC (permalink / raw)
To: kernelnewbies
Hi.
When I change something in the kernel and just hit make from toplevel
dir, it always compiles everything again, no matter if it wasn't changed
at all in the meantime.
I thought make should be able to make a second build time really quick.
What am I doing wrong? Is there a make target I don't know of? I don't
type in any, just make.
thanks,
martin
^ permalink raw reply [flat|nested] 7+ messages in thread* Rebuild a changed kernel quickly with make?
2013-07-04 6:33 Rebuild a changed kernel quickly with make? Martin Kepplinger
@ 2013-07-04 6:53 ` Warlich, Christof
2013-07-04 9:13 ` David kiarie
2013-07-04 18:18 ` Valdis.Kletnieks at vt.edu
2013-07-09 7:46 ` Srinivas Ganji
2 siblings, 1 reply; 7+ messages in thread
From: Warlich, Christof @ 2013-07-04 6:53 UTC (permalink / raw)
To: kernelnewbies
> When I change something in the kernel and just hit make from toplevel
> dir, it always compiles everything again, no matter if it wasn't changed
> at all in the meantime.
> I thought make should be able to make a second build time really quick.
> What am I doing wrong? Is there a make target I don't know of? I don't
> type in any, just make.
Are you sure it rebuilds _everything_, i.e. as in a fresh build or after a "make clean?"
When I rerun make without changing anything, it just does the following, which is much
Less than a complete build:
$ make
make -C /root/views/DCUOS_3/derived/tdc/kernel O=/root/views/DCUOS_3/derived/tdc/kernelObjects/.
Using /root/views/DCUOS_3/derived/tdc/kernel as source for kernel
GEN /root/views/DCUOS_3/derived/tdc/kernelObjects/Makefile
CHK include/linux/version.h
CHK include/linux/utsrelease.h
SYMLINK include/asm -> include/asm-x86
CALL /root/views/DCUOS_3/derived/tdc/kernel/scripts/checksyscalls.sh
CHK include/linux/compile.h
VDSOSYM arch/x86/vdso/vdso32-int80-syms.lds
VDSOSYM arch/x86/vdso/vdso32-sysenter-syms.lds
VDSOSYM arch/x86/vdso/vdso32-syms.lds
LD arch/x86/vdso/built-in.o
LD arch/x86/built-in.o
LD vmlinux.o
MODPOST vmlinux.o
GEN .version
CHK include/linux/compile.h
UPD include/linux/compile.h
CC init/version.o
LD init/built-in.o
LD .tmp_vmlinux1
KSYM .tmp_kallsyms1.S
AS .tmp_kallsyms1.o
LD .tmp_vmlinux2
KSYM .tmp_kallsyms2.S
AS .tmp_kallsyms2.o
LD vmlinux
SYSMAP System.map
SYSMAP .tmp_System.map
VOFFSET arch/x86/boot/voffset.h
OBJCOPY arch/x86/boot/compressed/vmlinux.bin
GZIP arch/x86/boot/compressed/vmlinux.bin.gz
MKPIGGY arch/x86/boot/compressed/piggy.S
AS arch/x86/boot/compressed/piggy.o
LD arch/x86/boot/compressed/vmlinux
ZOFFSET arch/x86/boot/zoffset.h
AS arch/x86/boot/header.o
CC arch/x86/boot/version.o
LD arch/x86/boot/setup.elf
OBJCOPY arch/x86/boot/setup.bin
OBJCOPY arch/x86/boot/vmlinux.bin
BUILD arch/x86/boot/bzImage
Root device is (8, 5)
Setup is 11148 bytes (padded to 11264 bytes).
System is 1759 kB
CRC f583db84
Kernel: arch/x86/boot/bzImage is ready (#3)
Building modules, stage 2.
MODPOST 1 modules
^ permalink raw reply [flat|nested] 7+ messages in thread
* Rebuild a changed kernel quickly with make?
2013-07-04 6:53 ` Warlich, Christof
@ 2013-07-04 9:13 ` David kiarie
2013-07-04 12:59 ` Martin Kepplinger
0 siblings, 1 reply; 7+ messages in thread
From: David kiarie @ 2013-07-04 9:13 UTC (permalink / raw)
To: kernelnewbies
On Thu, Jul 4, 2013 at 9:53 AM, Warlich, Christof <
christof.warlich@siemens.com> wrote:
> > When I change something in the kernel and just hit make from toplevel
> > dir, it always compiles everything again, no matter if it wasn't changed
> > at all in the meantime.
> > I thought make should be able to make a second build time really quick.
> > What am I doing wrong? Is there a make target I don't know of? I don't
> > type in any, just make.
>
> Are you sure it rebuilds _everything_, i.e. as in a fresh build or after a
> "make clean?"
>
> When I rerun make without changing anything, it just does the following,
> which is much
> Less than a complete build:
>
> $ make
> make -C /root/views/DCUOS_3/derived/tdc/kernel
> O=/root/views/DCUOS_3/derived/tdc/kernelObjects/.
> Using /root/views/DCUOS_3/derived/tdc/kernel as source for kernel
> GEN /root/views/DCUOS_3/derived/tdc/kernelObjects/Makefile
> CHK include/linux/version.h
> CHK include/linux/utsrelease.h
> SYMLINK include/asm -> include/asm-x86
> CALL /root/views/DCUOS_3/derived/tdc/kernel/scripts/checksyscalls.sh
> CHK include/linux/compile.h
> VDSOSYM arch/x86/vdso/vdso32-int80-syms.lds
> VDSOSYM arch/x86/vdso/vdso32-sysenter-syms.lds
> VDSOSYM arch/x86/vdso/vdso32-syms.lds
> LD arch/x86/vdso/built-in.o
> LD arch/x86/built-in.o
> LD vmlinux.o
> MODPOST vmlinux.o
> GEN .version
> CHK include/linux/compile.h
> UPD include/linux/compile.h
> CC init/version.o
> LD init/built-in.o
> LD .tmp_vmlinux1
> KSYM .tmp_kallsyms1.S
> AS .tmp_kallsyms1.o
> LD .tmp_vmlinux2
> KSYM .tmp_kallsyms2.S
> AS .tmp_kallsyms2.o
> LD vmlinux
> SYSMAP System.map
> SYSMAP .tmp_System.map
> VOFFSET arch/x86/boot/voffset.h
> OBJCOPY arch/x86/boot/compressed/vmlinux.bin
> GZIP arch/x86/boot/compressed/vmlinux.bin.gz
> MKPIGGY arch/x86/boot/compressed/piggy.S
> AS arch/x86/boot/compressed/piggy.o
> LD arch/x86/boot/compressed/vmlinux
> ZOFFSET arch/x86/boot/zoffset.h
> AS arch/x86/boot/header.o
> CC arch/x86/boot/version.o
> LD arch/x86/boot/setup.elf
> OBJCOPY arch/x86/boot/setup.bin
> OBJCOPY arch/x86/boot/vmlinux.bin
> BUILD arch/x86/boot/bzImage
> Root device is (8, 5)
> Setup is 11148 bytes (padded to 11264 bytes).
> System is 1759 kB
> CRC f583db84
> Kernel: arch/x86/boot/bzImage is ready (#3)
> Building modules, stage 2.
> MODPOST 1 modules
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
Am also pretty sure it does not compile everything.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20130704/81acdb94/attachment.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* Rebuild a changed kernel quickly with make?
2013-07-04 9:13 ` David kiarie
@ 2013-07-04 12:59 ` Martin Kepplinger
0 siblings, 0 replies; 7+ messages in thread
From: Martin Kepplinger @ 2013-07-04 12:59 UTC (permalink / raw)
To: kernelnewbies
On 04.07.2013 11:13, David kiarie wrote:
>
>
> On Thu, Jul 4, 2013 at 9:53 AM, Warlich, Christof
> <christof.warlich at siemens.com <mailto:christof.warlich@siemens.com>> wrote:
>
> > When I change something in the kernel and just hit make from toplevel
> > dir, it always compiles everything again, no matter if it wasn't
> changed
> > at all in the meantime.
> > I thought make should be able to make a second build time really
> quick.
> > What am I doing wrong? Is there a make target I don't know of? I don't
> > type in any, just make.
>
> Are you sure it rebuilds _everything_, i.e. as in a fresh build or
> after a "make clean?"
>
> When I rerun make without changing anything, it just does the
> following, which is much
> Less than a complete build:
>
> $ make
> make -C /root/views/DCUOS_3/derived/tdc/kernel
> O=/root/views/DCUOS_3/derived/tdc/kernelObjects/.
> Using /root/views/DCUOS_3/derived/tdc/kernel as source for kernel
> GEN /root/views/DCUOS_3/derived/tdc/kernelObjects/Makefile
> CHK include/linux/version.h
> CHK include/linux/utsrelease.h
> SYMLINK include/asm -> include/asm-x86
> CALL
> /root/views/DCUOS_3/derived/tdc/kernel/scripts/checksyscalls.sh
> CHK include/linux/compile.h
> VDSOSYM arch/x86/vdso/vdso32-int80-syms.lds
> VDSOSYM arch/x86/vdso/vdso32-sysenter-syms.lds
> VDSOSYM arch/x86/vdso/vdso32-syms.lds
> LD arch/x86/vdso/built-in.o
> LD arch/x86/built-in.o
> LD vmlinux.o
> MODPOST vmlinux.o
> GEN .version
> CHK include/linux/compile.h
> UPD include/linux/compile.h
> CC init/version.o
> LD init/built-in.o
> LD .tmp_vmlinux1
> KSYM .tmp_kallsyms1.S
> AS .tmp_kallsyms1.o
> LD .tmp_vmlinux2
> KSYM .tmp_kallsyms2.S
> AS .tmp_kallsyms2.o
> LD vmlinux
> SYSMAP System.map
> SYSMAP .tmp_System.map
> VOFFSET arch/x86/boot/voffset.h
> OBJCOPY arch/x86/boot/compressed/vmlinux.bin
> GZIP arch/x86/boot/compressed/vmlinux.bin.gz
> MKPIGGY arch/x86/boot/compressed/piggy.S
> AS arch/x86/boot/compressed/piggy.o
> LD arch/x86/boot/compressed/vmlinux
> ZOFFSET arch/x86/boot/zoffset.h
> AS arch/x86/boot/header.o
> CC arch/x86/boot/version.o
> LD arch/x86/boot/setup.elf
> OBJCOPY arch/x86/boot/setup.bin
> OBJCOPY arch/x86/boot/vmlinux.bin
> BUILD arch/x86/boot/bzImag
> Setup is 11148 bytes (padded to 11264 bytes).
> System is 1759 kB
> CRC f583db84
> Kernel: arch/x86/boot/bzImage is ready (#3)
> Building modules, stage 2.
> MODPOST 1 modules
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org <mailto:Kernelnewbies@kernelnewbies.org>
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
> Am also pretty sure it does not compile everything.
>
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
indeed it doesn't compile everything but a lot (or all?) modules for
example. A build with very little changes lasts more than half the time
a fresh clean build lasts. But I don't seem to do anything wrong then,
just wanted to check if I can do something about it. thanks!!
martin
^ permalink raw reply [flat|nested] 7+ messages in thread
* Rebuild a changed kernel quickly with make?
2013-07-04 6:33 Rebuild a changed kernel quickly with make? Martin Kepplinger
2013-07-04 6:53 ` Warlich, Christof
@ 2013-07-04 18:18 ` Valdis.Kletnieks at vt.edu
2013-07-09 7:46 ` Srinivas Ganji
2 siblings, 0 replies; 7+ messages in thread
From: Valdis.Kletnieks at vt.edu @ 2013-07-04 18:18 UTC (permalink / raw)
To: kernelnewbies
On Thu, 04 Jul 2013 08:33:00 +0200, Martin Kepplinger said:
> When I change something in the kernel and just hit make from toplevel
> dir, it always compiles everything again, no matter if it wasn't changed
> at all in the meantime.
It *really* depends on which CONFIG_ variable you change.
If you change some CONFIG_ variables like the ones that control whether
a specific module is built, the rebuild may in fact only compile 1 or 2
.c files and link the module into a .ko and be done. Maybe a few more
if you have /proc/config.gz enabled, because then it has to rebuild and
relink the data for that into the kernel.
THe gotcha is that changing other CONFIG_ variables can result in almost
everything being rebuilt - for instance, if you change a CONFIG_ that
controls a #ifdef in sched.h or one of the base networking headers, that
will cause a recompile of everything that includes that .h (and pretty
much everybody and their pet llama ends up including sched.h indirectly).
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 865 bytes
Desc: not available
Url : http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20130704/d6a21077/attachment.bin
^ permalink raw reply [flat|nested] 7+ messages in thread
* Rebuild a changed kernel quickly with make?
2013-07-04 6:33 Rebuild a changed kernel quickly with make? Martin Kepplinger
2013-07-04 6:53 ` Warlich, Christof
2013-07-04 18:18 ` Valdis.Kletnieks at vt.edu
@ 2013-07-09 7:46 ` Srinivas Ganji
2013-07-09 14:21 ` Valdis.Kletnieks at vt.edu
2 siblings, 1 reply; 7+ messages in thread
From: Srinivas Ganji @ 2013-07-09 7:46 UTC (permalink / raw)
To: kernelnewbies
Hi Martin,
You can pass the name of the target to the make for building only the
specified files and objects. Suppose, if I changed some modifications in
storage files, then I need to do make as shown below, from the top level
directory i.e. /usr/src/<linux-kernel>/
make M=drivers/usb/storage
I hope this helps to you. I got the same problem earlier and I fixed like
this.
Thank you,
Regards,
Srinivas
On Thu, Jul 4, 2013 at 12:03 PM, Martin Kepplinger <martink@posteo.de>wrote:
> Hi.
>
> When I change something in the kernel and just hit make from toplevel
> dir, it always compiles everything again, no matter if it wasn't changed
> at all in the meantime.
> I thought make should be able to make a second build time really quick.
> What am I doing wrong? Is there a make target I don't know of? I don't
> type in any, just make.
>
> thanks,
>
> martin
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20130709/07bc3a7d/attachment.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* Rebuild a changed kernel quickly with make?
2013-07-09 7:46 ` Srinivas Ganji
@ 2013-07-09 14:21 ` Valdis.Kletnieks at vt.edu
0 siblings, 0 replies; 7+ messages in thread
From: Valdis.Kletnieks at vt.edu @ 2013-07-09 14:21 UTC (permalink / raw)
To: kernelnewbies
On Tue, 09 Jul 2013 13:16:53 +0530, Srinivas Ganji said:
> You can pass the name of the target to the make for building only the
> specified files and objects. Suppose, if I changed some modifications in
> storage files, then I need to do make as shown below, from the top level
> directory i.e. /usr/src/<linux-kernel>/
>
> make M=drivers/usb/storage
>
> I hope this helps to you. I got the same problem earlier and I fixed like
> this.
This is good for testing, but do *not* bet on this producing a working kernel.
It's possible to build a module that doesn't match the rest of
your kernel, resulting in hard-to-debug oopses.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 865 bytes
Desc: not available
Url : http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20130709/f9ecbab1/attachment.bin
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2013-07-09 14:21 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-07-04 6:33 Rebuild a changed kernel quickly with make? Martin Kepplinger
2013-07-04 6:53 ` Warlich, Christof
2013-07-04 9:13 ` David kiarie
2013-07-04 12:59 ` Martin Kepplinger
2013-07-04 18:18 ` Valdis.Kletnieks at vt.edu
2013-07-09 7:46 ` Srinivas Ganji
2013-07-09 14:21 ` Valdis.Kletnieks at vt.edu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).