Messages in this thread Patch in this message | | | From | Frederic Weisbecker <> | Subject | [PATCH 2/3] housekeeping: Add basic isolcpus flags | Date | Wed, 25 Oct 2017 05:27:16 +0200 |
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Add flags to control nohz and domain isolations from "isolcpus=", in order to centralize the isolation features to a common interface. Domain isolation remains the default so not to break the existing isolcpus boot paramater behaviour.
Further flags in the future may include 0hz (1hz tick offload) and timers, workqueue, RCU, kthread, watchdog, likely all merged together in a common flag ("async"?). In any case, this will have to be modifiable by cpusets.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Galbraith <efault@gmx.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Wanpeng Li <kernellwp@gmail.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> --- kernel/housekeeping.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/kernel/housekeeping.c b/kernel/housekeeping.c index 88bd83b..8c53c66 100644 --- a/kernel/housekeeping.c +++ b/kernel/housekeeping.c @@ -11,6 +11,7 @@ #include <linux/init.h> #include <linux/kernel.h> #include <linux/static_key.h> +#include <linux/ctype.h> DEFINE_STATIC_KEY_FALSE(housekeeping_overriden); EXPORT_SYMBOL_GPL(housekeeping_overriden); @@ -122,6 +123,29 @@ __setup("nohz_full=", housekeeping_nohz_full_setup); static int __init housekeeping_isolcpus_setup(char *str) { - return housekeeping_setup(str, HK_FLAG_DOMAIN); + unsigned int flags = 0; + + while (isalpha(*str)) { + if (!strncmp(str, "nohz,", 5)) { + str += 5; + flags |= HK_FLAG_TICK; + continue; + } + + if (!strncmp(str, "domain,", 7)) { + str += 7; + flags |= HK_FLAG_DOMAIN; + continue; + } + + pr_warn("isolcpus: Error, unknown flag\n"); + return 0; + } + + /* Default behaviour for isolcpus without flags */ + if (!flags) + flags |= HK_FLAG_DOMAIN; + + return housekeeping_setup(str, flags); } __setup("isolcpus=", housekeeping_isolcpus_setup); -- 2.7.4
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