From de8e71ca4f2e17329f6718ae88d5c8336cb249ee Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 27 Aug 2011 22:39:09 +0100 Subject: ARM: pm: only use preallocated page table during resume Only use the preallocated page table during the resume, not while suspending. This avoids the overhead of having to switch unnecessarily to the resume page table in the suspend path. Tested-by: Santosh Shilimkar Tested-by: Shawn Guo Tested-by: Lorenzo Pieralisi Signed-off-by: Russell King --- arch/arm/kernel/suspend.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'arch/arm/kernel/suspend.c') diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c index 0a33f109549d..2beda56e4574 100644 --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -24,14 +24,17 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) return -EINVAL; /* - * Temporarily switch the page tables to our suspend page - * tables, which contain the temporary identity mapping - * required for resuming. + * Provide a temporary page table with an identity mapping for + * the MMU-enable code, required for resuming. On successful + * resume (indicated by a zero return code), we need to switch + * back to the correct page tables. */ - cpu_switch_mm(suspend_pgd, mm); - ret = __cpu_suspend(0, PHYS_OFFSET - PAGE_OFFSET, arg, fn); - cpu_switch_mm(mm->pgd, mm); - local_flush_tlb_all(); + ret = __cpu_suspend(virt_to_phys(suspend_pgd), + PHYS_OFFSET - PAGE_OFFSET, arg, fn); + if (ret == 0) { + cpu_switch_mm(mm->pgd, mm); + local_flush_tlb_all(); + } return ret; } -- cgit v1.2.3