From cc57165874e938ef684d71ba7d36e7088b551489 Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Mon, 9 Jan 2006 20:51:41 -0800 Subject: [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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/crash.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/i386/kernel/crash.c') diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c index 10fe6569751e..f1e65c2ead6e 100644 --- a/arch/i386/kernel/crash.c +++ b/arch/i386/kernel/crash.c @@ -25,7 +25,6 @@ #include -note_buf_t crash_notes[NR_CPUS]; /* This keeps a track of which one is crashing cpu. */ static int crashing_cpu; @@ -72,7 +71,9 @@ static void crash_save_this_cpu(struct pt_regs *regs, int cpu) * squirrelled away. ELF notes happen to provide * all of that that no need to invent something new. */ - buf = &crash_notes[cpu][0]; + buf = (u32*)per_cpu_ptr(crash_notes, cpu); + if (!buf) + return; memset(&prstatus, 0, sizeof(prstatus)); prstatus.pr_pid = current->pid; elf_core_copy_regs(&prstatus.pr_reg, regs); -- cgit v1.2.3-59-g8ed1b