From: Namhyung Kim <namhyung@kernel.org>
To: Robert Richter <rric@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Jiri Olsa <jolsa@redhat.com>,
linux-kernel@vger.kernel.org, Borislav Petkov <bp@suse.de>,
Robert Richter <robert.richter@linaro.org>
Subject: Re: [PATCH v2 03/14] perf: Add persistent event facilities
Date: Fri, 14 Jun 2013 11:15:13 +0900 [thread overview]
Message-ID: <87ehc530b2.fsf@sejong.aot.lge.com> (raw)
In-Reply-To: <1370968960-22527-4-git-send-email-rric@kernel.org> (Robert Richter's message of "Tue, 11 Jun 2013 18:42:29 +0200")
Hi Robert and Boris,
On Tue, 11 Jun 2013 18:42:29 +0200, Robert Richter wrote:
> From: Borislav Petkov <bp@alien8.de>
>
> Add a barebones implementation for registering persistent events with
> perf. For that, we don't destroy the buffers when they're unmapped;
> also, we map them read-only so that multiple agents can access them.
>
> Also, we allocate the event buffers at event init time and not at mmap
> time so that we can log samples into them regardless of whether there
> are readers in userspace or not.
>
> Changes made by Robert Richter <robert.richter@linaro.org>:
>
> * Fixing wrongly determined attribute size.
>
> * The default buffer size used to setup event buffers with perf tools
> is 512k. Using the same buffer size for persistent events. This also
> avoids failed mmap calls due to different buffer sizes.
>
> * Improve error reporting.
>
> * Returning -ENODEV if no file descriptor is found. An error code of
> -1 (-EPERM) is misleading in this case.
>
> * Adding cpu check to perf_get_persistent_event_fd()
>
> [ make percpu variable static ]
> Reported-by: Fengguang Wu <fengguang.wu@intel.com>
> Signed-off-by: Borislav Petkov <bp@suse.de>
> [ Fix attr size ]
> [ Setting default buffer size to 512k as in perf tools ]
> [ Print error code on failure when adding events ]
> [ Return resonable error code ]
> [ Adding cpu check to perf_get_persistent_event_fd() ]
> Reported-by: Jiri Olsa <jolsa@redhat.com>
> Signed-off-by: Robert Richter <robert.richter@linaro.org>
> Signed-off-by: Robert Richter <rric@kernel.org>
[SNIP]
> +int perf_add_persistent_event_by_id(int id)
> +{
> + struct perf_event_attr *attr;
> +
> + attr = kzalloc(sizeof(*attr), GFP_KERNEL);
> + if (!attr)
> + return -ENOMEM;
> +
> + attr->sample_period = 1;
> + attr->wakeup_events = 1;
> + attr->sample_type = PERF_SAMPLE_RAW;
> + attr->persistent = 1;
> + attr->config = id;
> + attr->type = PERF_TYPE_TRACEPOINT;
> + attr->size = sizeof(*attr);
> +
> + return perf_add_persistent_event(attr, CPU_BUFFER_NR_PAGES);
> +}
> +
> +int perf_get_persistent_event_fd(unsigned cpu, struct perf_event_attr *attr)
> +{
> + struct pers_event_desc *desc;
> +
> + if (cpu >= (unsigned)nr_cpu_ids)
> + return -EINVAL;
> +
> + list_for_each_entry(desc, &per_cpu(pers_events, cpu), plist)
> + if (desc->attr->config == attr->config)
> + return __alloc_persistent_event_fd(desc);
> +
So it only supports tracepoint events. Don't we need to add other types
of event?
Thanks,
Namhyung
> + return -ENODEV;
> +}
> +
> +
> +void __init persistent_events_init(void)
> +{
> + int i;
> +
> + for_each_possible_cpu(i)
> + INIT_LIST_HEAD(&per_cpu(pers_events, i));
> +}
next prev parent reply other threads:[~2013-06-14 2:15 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-11 16:42 [PATCH v2 00/14] perf, persistent: Kernel updates for perf tool integration Robert Richter
2013-06-11 16:42 ` [PATCH v2 01/14] perf, ring_buffer: Use same prefix Robert Richter
2013-06-11 16:42 ` [PATCH v2 02/14] perf: Add persistent events Robert Richter
2013-06-24 9:28 ` Peter Zijlstra
2013-06-24 19:24 ` Borislav Petkov
2013-06-25 8:46 ` Robert Richter
2013-06-11 16:42 ` [PATCH v2 03/14] perf: Add persistent event facilities Robert Richter
2013-06-14 2:15 ` Namhyung Kim [this message]
2013-06-14 7:20 ` Robert Richter
2013-06-24 9:32 ` Peter Zijlstra
2013-06-25 8:47 ` Robert Richter
2013-06-24 9:44 ` Peter Zijlstra
2013-06-25 8:41 ` Robert Richter
2013-06-24 9:48 ` Peter Zijlstra
2013-06-24 19:26 ` Borislav Petkov
2013-06-25 7:44 ` Peter Zijlstra
2013-06-25 9:24 ` Robert Richter
2013-06-25 9:37 ` Borislav Petkov
2013-06-25 10:51 ` Robert Richter
2013-06-25 15:29 ` Borislav Petkov
2013-06-25 16:14 ` Robert Richter
2013-06-11 16:42 ` [PATCH v2 04/14] MCE: Enable persistent event Robert Richter
2013-06-11 16:42 ` [PATCH v2 05/14] perf, persistent: Rework struct pers_event_desc Robert Richter
2013-06-11 16:42 ` [PATCH v2 06/14] perf, persistent: Remove rb_put() Robert Richter
2013-06-11 16:42 ` [PATCH v2 07/14] perf, persistent: Introduce get_persistent_event() Robert Richter
2013-06-11 16:42 ` [PATCH v2 08/14] perf, persistent: Reworking perf_get_persistent_event_fd() Robert Richter
2013-06-11 16:42 ` [PATCH v2 09/14] perf, persistent: Protect event lists with mutex Robert Richter
2013-06-11 16:42 ` [PATCH v2 10/14] perf, persistent: Avoid adding identical events Robert Richter
2013-06-11 16:42 ` [PATCH v2 11/14] perf, persistent: Implementing a persistent pmu Robert Richter
2013-06-11 16:42 ` [PATCH v2 12/14] perf, persistent: Name each persistent event Robert Richter
2013-06-11 16:42 ` [PATCH v2 13/14] perf, persistent: Exposing persistent events using sysfs Robert Richter
2013-06-14 2:36 ` Namhyung Kim
2013-06-14 8:57 ` Robert Richter
2013-06-11 16:42 ` [PATCH v2 14/14] perf, persistent: Allow multiple users for an event Robert Richter
2013-06-24 10:08 ` [PATCH v2 00/14] perf, persistent: Kernel updates for perf tool integration Peter Zijlstra
2013-06-25 10:46 ` Robert Richter
2013-06-24 10:22 ` Peter Zijlstra
2013-06-25 16:56 ` Robert Richter
2013-06-24 10:24 ` Peter Zijlstra
2013-06-24 15:25 ` Peter Zijlstra
2013-06-24 19:45 ` Ingo Molnar
2013-06-25 17:57 ` Robert Richter
2013-06-25 19:16 ` Borislav Petkov
2013-06-26 8:12 ` Robert Richter
2013-06-26 8:24 ` Borislav Petkov
2013-06-26 9:46 ` Ingo Molnar
2013-06-26 9:56 ` Borislav Petkov
2013-06-26 10:11 ` Robert Richter
2013-06-26 11:45 ` Ingo Molnar
2013-06-26 12:25 ` Ingo Molnar
2013-06-26 12:44 ` Robert Richter
2013-06-27 5:46 ` Namhyung Kim
2013-06-27 8:35 ` Borislav Petkov
2013-06-27 8:50 ` Ingo Molnar
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