From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sourabh Jain Date: Mon, 23 May 2022 14:06:42 +0530 Subject: [PATCH v8 3/7] crash: add generic infrastructure for crash hotplug support In-Reply-To: <20220505184603.1548-4-eric.devolder@oracle.com> References: <20220505184603.1548-1-eric.devolder@oracle.com> <20220505184603.1548-4-eric.devolder@oracle.com> Message-ID: <88ec248e-e00f-a84e-c652-97e49fbf2674@linux.ibm.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kexec@lists.infradead.org Hello Eric, On 06/05/22 00:15, Eric DeVolder wrote: > CPU and memory change notifications are received in order to > regenerate the elfcorehdr. > > To support cpu hotplug, a callback is registered to capture the > CPUHP_AP_ONLINE_DYN online and offline events via > cpuhp_setup_state_nocalls(). > > To support memory hotplug, a notifier is registered to capture the > MEM_ONLINE and MEM_OFFLINE events via register_memory_notifier(). > > The cpu callback and memory notifiers call handle_hotplug_event() > to handle the hot plug/unplug event. Then handle_hotplug_event() > dispatches the event to the architecture specific > arch_crash_handle_hotplug_event(). During the process, the > kexec_mutex is held. > > Signed-off-by: Eric DeVolder > --- > include/linux/crash_core.h | 10 +++++ > include/linux/kexec.h | 5 +++ > kernel/crash_core.c | 92 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 107 insertions(+) > > diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h > index de62a722431e..a240f84348aa 100644 > --- a/include/linux/crash_core.h > +++ b/include/linux/crash_core.h > @@ -84,4 +84,14 @@ int parse_crashkernel_high(char *cmdline, unsigned long long system_ram, > int parse_crashkernel_low(char *cmdline, unsigned long long system_ram, > unsigned long long *crash_size, unsigned long long *crash_base); > > +#define KEXEC_CRASH_HP_REMOVE_CPU 0 > +#define KEXEC_CRASH_HP_ADD_CPU 1 > +#define KEXEC_CRASH_HP_REMOVE_MEMORY 2 > +#define KEXEC_CRASH_HP_ADD_MEMORY 3 > +#define KEXEC_CRASH_HP_INVALID_CPU -1U > + > +struct kimage; > +void arch_crash_handle_hotplug_event(struct kimage *image, unsigned int hp_action, > + unsigned int cpu); > + > #endif /* LINUX_CRASH_CORE_H */ > diff --git a/include/linux/kexec.h b/include/linux/kexec.h > index f93f2591fc1e..5935bc78ed7f 100644 > --- a/include/linux/kexec.h > +++ b/include/linux/kexec.h > @@ -308,6 +308,11 @@ struct kimage { > struct purgatory_info purgatory_info; > #endif > > + bool hotplug_event; > + unsigned int offlinecpu; > + bool elfcorehdr_index_valid; > + int elfcorehdr_index; How about keeping above kimage elements under below config? #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_MEMORY_HOTPLUG) Thanks, Sourabh Jain