On 2021-03-19 15:23:26, Pavel Tatashin wrote: > kmsg_dump(KMSG_DUMP_SHUTDOWN) is called before > machine_restart(), machine_halt(), machine_power_off(), the only one that > is missing is machine_kexec(). > > The dmesg output that it contains can be used to study the shutdown > performance of both kernel and systemd during kexec reboot. > > Here is example of dmesg data collected after kexec: > > root@dplat-cp22:~# cat /sys/fs/pstore/dmesg-ramoops-0 | tail > ... > <6>[ 70.914592] psci: CPU3 killed (polled 0 ms) > <5>[ 70.915705] CPU4: shutdown > <6>[ 70.916643] psci: CPU4 killed (polled 4 ms) > <5>[ 70.917715] CPU5: shutdown > <6>[ 70.918725] psci: CPU5 killed (polled 0 ms) > <5>[ 70.919704] CPU6: shutdown > <6>[ 70.920726] psci: CPU6 killed (polled 4 ms) > <5>[ 70.921642] CPU7: shutdown > <6>[ 70.922650] psci: CPU7 killed (polled 0 ms) > > Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > Reviewed-by: Petr Mladek <pmladek@xxxxxxxx> > Reviewed-by: Bhupesh Sharma <bhsharma@xxxxxxxxxx> Reviewed-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx> Tyler > Acked-by: Baoquan He <bhe@xxxxxxxxxx> > --- > kernel/kexec_core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c > index a0b6780740c8..6ee4a1cf6e8e 100644 > --- a/kernel/kexec_core.c > +++ b/kernel/kexec_core.c > @@ -37,6 +37,7 @@ > #include <linux/compiler.h> > #include <linux/hugetlb.h> > #include <linux/objtool.h> > +#include <linux/kmsg_dump.h> > > #include <asm/page.h> > #include <asm/sections.h> > @@ -1179,6 +1180,7 @@ int kernel_kexec(void) > machine_shutdown(); > } > > + kmsg_dump(KMSG_DUMP_SHUTDOWN); > machine_kexec(kexec_image); > > #ifdef CONFIG_KEXEC_JUMP > -- > 2.25.1 > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
