lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-Id: <1356799386-4212-26-git-send-email-fweisbec@gmail.com> Date: Sat, 29 Dec 2012 17:43:04 +0100 From: Frederic Weisbecker <fweisbec@...il.com> To: LKML <linux-kernel@...r.kernel.org> Cc: Frederic Weisbecker <fweisbec@...il.com>, Alessio Igor Bogani <abogani@...nel.org>, Andrew Morton <akpm@...ux-foundation.org>, Chris Metcalf <cmetcalf@...era.com>, Christoph Lameter <cl@...ux.com>, Geoff Levand <geoff@...radead.org>, Gilad Ben Yossef <gilad@...yossef.com>, Hakan Akkan <hakanakkan@...il.com>, Ingo Molnar <mingo@...nel.org>, "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>, Paul Gortmaker <paul.gortmaker@...driver.com>, Peter Zijlstra <peterz@...radead.org>, Steven Rostedt <rostedt@...dmis.org>, Thomas Gleixner <tglx@...utronix.de> Subject: [PATCH 25/27] rcu: Don't keep the tick for RCU while in userspace If we are interrupting userspace, we don't need to keep the tick for RCU: quiescent states don't need to be reported because we soon run in userspace and local callbacks are handled by the nocb threads. CHECKME: Do the nocb threads actually handle the global grace period completion for local callbacks? Signed-off-by: Frederic Weisbecker <fweisbec@...il.com> Cc: Alessio Igor Bogani <abogani@...nel.org> Cc: Andrew Morton <akpm@...ux-foundation.org> Cc: Chris Metcalf <cmetcalf@...era.com> Cc: Christoph Lameter <cl@...ux.com> Cc: Geoff Levand <geoff@...radead.org> Cc: Gilad Ben Yossef <gilad@...yossef.com> Cc: Hakan Akkan <hakanakkan@...il.com> Cc: Ingo Molnar <mingo@...nel.org> Cc: Paul E. McKenney <paulmck@...ux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@...driver.com> Cc: Peter Zijlstra <peterz@...radead.org> Cc: Steven Rostedt <rostedt@...dmis.org> Cc: Thomas Gleixner <tglx@...utronix.de> --- kernel/time/tick-sched.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 0e1ebff..76d1b08 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -22,6 +22,7 @@ #include <linux/module.h> #include <linux/irq_work.h> #include <linux/posix-timers.h> +#include <linux/context_tracking.h> #include <asm/irq_regs.h> @@ -604,10 +605,9 @@ static bool can_stop_full_tick(int cpu) /* * Keep the tick if we are asked to report a quiescent state. - * This must be further optimized (avoid checks for local callbacks, - * ignore RCU in userspace, etc... + * This must be further optimized (avoid checks for local callbacks) */ - if (rcu_pending(cpu)) { + if (!context_tracking_in_user() && rcu_pending(cpu)) { trace_printk("Can't stop: RCU pending\n"); return false; } -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists