path: root/kernel/kexec.c
diff options
authorVivek Goyal <vgoyal@in.ibm.com>2006-01-09 20:51:41 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-10 08:01:26 -0800
commitcc57165874e938ef684d71ba7d36e7088b551489 (patch)
treee1847f5547a7a426214e9ef0719eab908ee305d7 /kernel/kexec.c
parent82409411571ad89d271dc46f7fa26149fad9efdf (diff)
[PATCH] kdump: dynamic per cpu allocation of memory for saving cpu registers
- In case of system crash, current state of cpu registers is saved in memory in elf note format. So far memory for storing elf notes was being allocated statically for NR_CPUS. - This patch introduces dynamic allocation of memory for storing elf notes. It uses alloc_percpu() interface. This should lead to better memory usage. - Introduced based on Andi Kleen's and Eric W. Biederman's suggestions. - This patch also moves memory allocation for elf notes from architecture dependent portion to architecture independent portion. Now crash_notes is architecture independent. The whole idea is that size of memory to be allocated per cpu (MAX_NOTE_BYTES) can be architecture dependent and allocation of this memory can be architecture independent. Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/kexec.c')
1 files changed, 16 insertions, 0 deletions
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 2c95848fbce..1197de8b2a9 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -26,6 +26,9 @@
#include <asm/system.h>
#include <asm/semaphore.h>
+/* Per cpu memory for storing cpu states in case of system crash. */
+note_buf_t* crash_notes;
/* Location of the reserved area for the crash kernel */
struct resource crashk_res = {
.name = "Crash kernel",
@@ -1060,3 +1063,16 @@ void crash_kexec(struct pt_regs *regs)
xchg(&kexec_lock, 0);
+static int __init crash_notes_memory_init(void)
+ /* Allocate memory for saving cpu registers. */
+ crash_notes = alloc_percpu(note_buf_t);
+ if (!crash_notes) {
+ printk("Kexec: Memory allocation for saving cpu register"
+ " states failed\n");
+ return -ENOMEM;
+ }
+ return 0;