From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: x86@kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
Kees Cook <keescook@chromium.org>
Subject: [patch 10/12] x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
Date: Thu, 04 Feb 2021 21:49:13 +0100 [thread overview]
Message-ID: <20210204211155.100196672@linutronix.de> (raw)
In-Reply-To: 20210204204903.350275743@linutronix.de
Now that all invocations of irq_exit_rcu() happen on the irq stack, turn on
CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK which causes the core code to invoke
__do_softirq() directly without going through do_softirq_own_stack().
That means do_softirq_own_stack() is only invoked from task context which
means it can't be on the irq stack. Remove the conditional from
run_softirq_on_irqstack_cond() and rename the function accordingly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/irq_stack.h | 19 ++++++++-----------
arch/x86/kernel/irq_64.c | 2 +-
3 files changed, 10 insertions(+), 12 deletions(-)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -187,6 +187,7 @@ config X86
select HAVE_HW_BREAKPOINT
select HAVE_IDE
select HAVE_IOREMAP_PROT
+ select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
--- a/arch/x86/include/asm/irq_stack.h
+++ b/arch/x86/include/asm/irq_stack.h
@@ -195,19 +195,16 @@
"call %P[__func] \n"
/*
- * Macro to invoke __do_softirq on the irq stack. Contrary to the above
- * the only check which is necessary is whether the interrupt stack is
- * in use already.
+ * Macro to invoke __do_softirq on the irq stack. This is only called from
+ * task context when bottom halfs are about to be reenabled and soft
+ * interrupts are pending to be processed. The interrupt stack cannot be in
+ * use here.
*/
-#define run_softirq_on_irqstack_cond() \
+#define run_softirq_on_irqstack() \
{ \
- if (__this_cpu_read(hardirq_stack_inuse)) { \
- __do_softirq(); \
- } else { \
- __this_cpu_write(hardirq_stack_inuse, true); \
- __call_on_irqstack(__do_softirq, ASM_CALL_SOFTIRQ); \
- __this_cpu_write(hardirq_stack_inuse, false); \
- } \
+ __this_cpu_write(hardirq_stack_inuse, true); \
+ __call_on_irqstack(__do_softirq, ASM_CALL_SOFTIRQ); \
+ __this_cpu_write(hardirq_stack_inuse, false); \
}
#else /* CONFIG_X86_64 */
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -76,5 +76,5 @@ int irq_init_percpu_irqstack(unsigned in
void do_softirq_own_stack(void)
{
- run_softirq_on_irqstack_cond();
+ run_softirq_on_irqstack();
}
next prev parent reply other threads:[~2021-02-05 1:02 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-04 20:49 [patch 00/12] x86/irq/64: Inline irq stack switching Thomas Gleixner
2021-02-04 20:49 ` [patch 01/12] x86/entry: Fix instrumentation annotation Thomas Gleixner
2021-02-05 12:02 ` Borislav Petkov
2021-02-04 20:49 ` [patch 02/12] x86/irq: Sanitize irq stack tracking Thomas Gleixner
2021-02-04 20:49 ` [patch 03/12] x86/irq/64: Adjust the per CPU irq stack pointer by 8 Thomas Gleixner
2021-02-05 13:53 ` Peter Zijlstra
2021-02-05 15:00 ` Thomas Gleixner
2021-02-04 20:49 ` [patch 04/12] x86/apic: Split out spurious handling code Thomas Gleixner
2021-02-04 20:49 ` [patch 05/12] x86/irq: Provide macro for inlining irq stack switching Thomas Gleixner
2021-02-08 15:06 ` Borislav Petkov
2021-02-08 20:42 ` Josh Poimboeuf
2021-02-09 15:12 ` Thomas Gleixner
2021-02-09 16:22 ` Josh Poimboeuf
2021-02-09 18:14 ` Thomas Gleixner
2021-02-04 20:49 ` [patch 06/12] x86/entry: Convert system vectors to irq stack macro Thomas Gleixner
2021-02-05 3:52 ` kernel test robot
2021-02-05 14:13 ` Peter Zijlstra
2021-02-07 8:15 ` [kbuild-all] " Rong Chen
2021-02-08 14:19 ` Borislav Petkov
2021-02-09 8:57 ` Rong Chen
2021-02-09 10:46 ` Borislav Petkov
2021-02-04 20:49 ` [patch 07/12] x86/entry: Convert device interrupts to inline stack switching Thomas Gleixner
2021-02-04 20:49 ` [patch 08/12] x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcall Thomas Gleixner
2021-02-05 7:28 ` kernel test robot
2021-02-04 20:49 ` [patch 09/12] x86/softirq: Remove indirection in do_softirq_own_stack() Thomas Gleixner
2021-02-04 20:49 ` Thomas Gleixner [this message]
2021-02-04 20:49 ` [patch 11/12] softirq: Allow inlining do_softirq_own_stack() Thomas Gleixner
2021-02-05 10:14 ` Lai Jiangshan
2021-02-05 11:38 ` Thomas Gleixner
2021-02-09 20:43 ` Thomas Gleixner
2021-02-04 20:49 ` [patch 12/12] x86/softirq/64: Inline do_softirq_own_stack() Thomas Gleixner
2021-02-08 21:47 ` [patch 00/12] x86/irq/64: Inline irq stack switching Kees Cook
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210204211155.100196672@linutronix.de \
--to=tglx@linutronix.de \
--cc=jpoimboe@redhat.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).