From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: [PATCH v11 9/9] cpuset: Allow reporting of sched domain generation info Date: Sun, 24 Jun 2018 15:30:40 +0800 Message-ID: <1529825440-9574-10-git-send-email-longman@redhat.com> References: <1529825440-9574-1-git-send-email-longman@redhat.com> Return-path: In-Reply-To: <1529825440-9574-1-git-send-email-longman@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tejun Heo , Li Zefan , Johannes Weiner , Peter Zijlstra , Ingo Molnar Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kernel-team@fb.com, pjt@google.com, luto@amacapital.net, Mike Galbraith , torvalds@linux-foundation.org, Roman Gushchin , Juri Lelli , Patrick Bellasi , Waiman Long This patch enables us to report sched domain generation information. If DYNAMIC_DEBUG is enabled, issuing the following command echo "file cpuset.c +p" > /sys/kernel/debug/dynamic_debug/control and setting loglevel to 8 will allow the kernel to show what scheduling domain changes are being made. Signed-off-by: Waiman Long --- kernel/cgroup/cpuset.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 07a5575..62b7e61 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -836,6 +836,23 @@ static int generate_sched_domains(cpumask_var_t **domains, return ndoms; } +#ifdef CONFIG_DEBUG_KERNEL +static inline void debug_print_domains(cpumask_var_t *doms, int ndoms) +{ + int i; + char buf[200]; + char *ptr, *end = buf + sizeof(buf) - 1; + + for (i = 0, ptr = buf, *end = '\0'; i < ndoms; i++) + ptr += snprintf(ptr, end - ptr, "dom%d=%*pbl ", i, + cpumask_pr_args(doms[i])); + + pr_debug("Generated %d domains: %s\n", ndoms, buf); +} +#else +static inline void debug_print_domains(cpumask_var_t *doms, int ndoms) { } +#endif + /* * Rebuild scheduler domains. * @@ -871,6 +888,7 @@ static void rebuild_sched_domains_locked(void) /* Generate domain masks and attrs */ ndoms = generate_sched_domains(&doms, &attr); + debug_print_domains(doms, ndoms); /* Have scheduler rebuild the domains */ partition_sched_domains(ndoms, doms, attr); -- 1.8.3.1