From: Peter Zijlstra <peterz@infradead.org>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, Kyle Huey <me@kylehuey.com>,
Alexandre Chartre <alexandre.chartre@oracle.com>,
Robert O'Callahan <rocallahan@gmail.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
Frederic Weisbecker <frederic@kernel.org>,
Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <sean.j.christopherson@intel.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Petr Mladek <pmladek@suse.com>,
Steven Rostedt <rostedt@goodmis.org>,
Joel Fernandes <joel@joelfernandes.org>,
Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Juergen Gross <jgross@suse.com>, Brian Gerst <brgerst@gmail.com>,
Andy Lutomirski <luto@kernel.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Daniel Thompson <daniel.thompson@linaro.org>,
Peter Zijlstra <peterz@infradead.org>
Subject: [PATCH 11/13] x86/debug: Simplify hw_breakpoint_handler()
Date: Wed, 02 Sep 2020 15:26:00 +0200 [thread overview]
Message-ID: <20200902133201.292906672@infradead.org> (raw)
In-Reply-To: 20200902132549.496605622@infradead.org
This is called with interrupts disabled, there's no point in using
get_cpu() and per_cpu().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kernel/hw_breakpoint.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -487,7 +487,7 @@ EXPORT_SYMBOL_GPL(hw_breakpoint_restore)
*/
static int hw_breakpoint_handler(struct die_args *args)
{
- int i, cpu, rc = NOTIFY_STOP;
+ int i, rc = NOTIFY_STOP;
struct perf_event *bp;
unsigned long dr6;
unsigned long *dr6_p;
@@ -505,12 +505,10 @@ static int hw_breakpoint_handler(struct
return NOTIFY_DONE;
/*
- * Assert that local interrupts are disabled
* Reset the DRn bits in the virtualized register value.
* The ptrace trigger routine will add in whatever is needed.
*/
current->thread.debugreg6 &= ~DR_TRAP_BITS;
- cpu = get_cpu();
/* Handle all the breakpoints that were triggered */
for (i = 0; i < HBP_NUM; ++i) {
@@ -525,7 +523,7 @@ static int hw_breakpoint_handler(struct
*/
rcu_read_lock();
- bp = per_cpu(bp_per_reg[i], cpu);
+ bp = this_cpu_read(bp_per_reg[i]);
/*
* Reset the 'i'th TRAP bit in dr6 to denote completion of
* exception handling
@@ -560,8 +558,6 @@ static int hw_breakpoint_handler(struct
(dr6 & (~DR_TRAP_BITS)))
rc = NOTIFY_DONE;
- put_cpu();
-
return rc;
}
next prev parent reply other threads:[~2020-09-02 13:57 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-02 13:25 [PATCH 00/13] x86/debug: Untangle handle_debug() Peter Zijlstra
2020-09-02 13:25 ` [PATCH 01/13] x86/entry: Fix AC assertion Peter Zijlstra
2020-09-02 15:58 ` Brian Gerst
2020-09-02 16:24 ` Jürgen Groß
2020-09-02 16:31 ` peterz
2020-09-02 17:02 ` Brian Gerst
2020-09-02 16:26 ` Andrew Cooper
2020-09-04 13:16 ` [tip: x86/urgent] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 02/13] x86/debug: Allow a single level of #DB recursion Peter Zijlstra
2020-09-02 23:59 ` Sasha Levin
2020-09-03 16:12 ` Josh Poimboeuf
2020-09-02 13:25 ` [PATCH 03/13] x86/debug: Sync BTF earlier Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 04/13] x86/debug: Move kprobe_debug_handler() into exc_debug_kernel() Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 05/13] x86/debug: Remove handle_debug(.user) argument Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 06/13] x86/debug: Simplify #DB signal code Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 07/13] x86/debug: Move historical SYSENTER junk into exc_debug_kernel() Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 08/13] x86/debug: Move cond_local_irq_enable() block into exc_debug_user() Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 09/13] x86/debug: Remove the historical junk Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:25 ` [PATCH 10/13] x86/debug: Remove aout_dump_debugregs() Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:26 ` Peter Zijlstra [this message]
2020-09-04 13:16 ` [tip: x86/entry] x86/debug: Simplify hw_breakpoint_handler() tip-bot2 for Peter Zijlstra
2020-09-02 13:26 ` [RFC][PATCH 12/13] x86/debug: Support negative polarity DR6 bits Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-02 13:26 ` [RFC][PATCH 13/13] x86/debug: Change thread.debugreg6 to thread.virtual_dr6 Peter Zijlstra
2020-09-04 13:16 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-09-03 15:21 ` [PATCH 00/13] x86/debug: Untangle handle_debug() Daniel Thompson
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