From aea8e7c80ab50305257838bfb04f91a76cf9fec7 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Mon, 26 Aug 2013 15:12:58 +0400 Subject: xtensa: check thread flags atomically on return from user exception Check pending signals and rescheduling thread flags with interrupts disabled, and don't enable them if no flags are set. Call trace_hardirqs_on after thread flags handling, so that rescheduling is done and hardirqs tracking flag is updated in the correct task context. Signed-off-by: Max Filippov Signed-off-by: Chris Zankel --- arch/xtensa/kernel/entry.S | 39 +++++++++++++++++++++------------------ 1 file changed, 21 insertions(+), 18 deletions(-) diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 9298742f0fd0..03709ef2f3ce 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -423,29 +423,14 @@ common_exception: .global common_exception_return common_exception_return: -#ifdef CONFIG_TRACE_IRQFLAGS - l32i a4, a1, PT_DEPC - /* Double exception means we came here with an exception - * while PS.EXCM was set, i.e. interrupts disabled. - */ - bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f - l32i a4, a1, PT_EXCCAUSE - bnei a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f - /* We came here with an interrupt means interrupts were enabled - * and we'll reenable them on return. - */ - movi a4, trace_hardirqs_on - callx4 a4 1: -#endif + rsil a2, LOCKLEVEL /* Jump if we are returning from kernel exceptions. */ -1: l32i a3, a1, PT_PS + l32i a3, a1, PT_PS _bbci.l a3, PS_UM_BIT, 4f - rsil a2, 0 - /* Specific to a user exception exit: * We need to check some flags for signal handling and rescheduling, * and have to restore WB and WS, extra states, and all registers @@ -465,6 +450,7 @@ common_exception_return: /* Call do_signal() */ + rsil a2, 0 movi a4, do_notify_resume # int do_notify_resume(struct pt_regs*) mov a6, a1 callx4 a4 @@ -472,6 +458,7 @@ common_exception_return: 3: /* Reschedule */ + rsil a2, 0 movi a4, schedule # void schedule (void) callx4 a4 j 1b @@ -483,7 +470,23 @@ common_exception_return: movi a4, check_tlb_sanity callx4 a4 #endif -4: /* Restore optional registers. */ +4: +#ifdef CONFIG_TRACE_IRQFLAGS + l32i a4, a1, PT_DEPC + /* Double exception means we came here with an exception + * while PS.EXCM was set, i.e. interrupts disabled. + */ + bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f + l32i a4, a1, PT_EXCCAUSE + bnei a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f + /* We came here with an interrupt means interrupts were enabled + * and we'll reenable them on return. + */ + movi a4, trace_hardirqs_on + callx4 a4 +1: +#endif + /* Restore optional registers. */ load_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT -- cgit v1.2.3-55-g7522