From: Max Filippov <jcmvbkbc@gmail.com>
To: Chris Zankel <chris@zankel.net>
Cc: Marc Gauthier <marc@tensilica.com>,
linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org,
Max Filippov <jcmvbkbc@gmail.com>
Subject: [PATCH v2 05/11] xtensa: check thread flags atomically on return from user exception
Date: Fri, 30 Aug 2013 19:34:57 +0400 [thread overview]
Message-ID: <1377876903-27860-6-git-send-email-jcmvbkbc@gmail.com> (raw)
In-Reply-To: <1377876903-27860-1-git-send-email-jcmvbkbc@gmail.com>
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 <jcmvbkbc@gmail.com>
---
Changes v1->v2:
- remove unneeded call to trace_hardirqs_off from the loop after
rsil a2, LOCKLEVEL
arch/xtensa/kernel/entry.S | 39 +++++++++++++++++++++------------------
1 files changed, 21 insertions(+), 18 deletions(-)
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 9298742..03709ef 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
--
1.7.7.6
next prev parent reply other threads:[~2013-08-30 15:35 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-30 15:34 [PATCH v2 00/11] xtensa queue 2013/08/30 Max Filippov
2013-08-30 15:34 ` [PATCH v2 01/11] xtensa: kernel: add "asm/ftrace.h" for pass compiling Max Filippov
2013-08-30 15:34 ` [PATCH v2 02/11] xtensa: fix arch spinlock function names Max Filippov
2013-08-30 15:34 ` [PATCH v2 03/11] xtensa: fix __delay for small loop count Max Filippov
2013-08-30 15:34 ` [PATCH v2 04/11] xtensa: fix build warning Max Filippov
2013-08-30 15:34 ` Max Filippov [this message]
2013-08-30 15:34 ` [PATCH v2 06/11] xtensa: enable kernel preemption Max Filippov
2013-08-30 15:34 ` [PATCH v2 07/11] xtensa: keep a3 and excsave1 on entry to exception handlers Max Filippov
2013-08-30 15:35 ` [PATCH v2 08/11] xtensa: new fast_alloca handler Max Filippov
2013-08-30 15:35 ` [PATCH v2 09/11] xtensa: don't use echo -e needlessly Max Filippov
2013-08-30 15:35 ` [PATCH v2 10/11] xtensa: fix !CONFIG_XTENSA_CALIBRATE_CCOUNT build failure Max Filippov
2013-08-30 15:35 ` [PATCH v2 11/11] xtensa: remove CCOUNT_PER_JIFFY Max Filippov
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