From: "Liang, Kan" <kan.liang@linux.intel.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: acme@kernel.org, tglx@linutronix.de, mingo@redhat.com,
linux-kernel@vger.kernel.org, eranian@google.com,
jolsa@redhat.com, namhyung@kernel.org, ak@linux.intel.com,
luto@amacapital.net, Vlastimil Babka <vbabka@suse.cz>,
kirill@shutemov.name
Subject: Re: [PATCH V4 01/13] perf/core, x86: Add PERF_SAMPLE_DATA_PAGE_SIZE
Date: Fri, 1 Feb 2019 09:45:59 -0500 [thread overview]
Message-ID: <48363dcc-2047-e311-9da1-98b598a39df7@linux.intel.com> (raw)
In-Reply-To: <20190201092240.GB31498@hirez.programming.kicks-ass.net>
On 2/1/2019 4:22 AM, Peter Zijlstra wrote:
> On Thu, Jan 31, 2019 at 12:27:54PM -0800, kan.liang@linux.intel.com wrote:
>> diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
>> index 374a197..229a73b 100644
>> --- a/arch/x86/events/core.c
>> +++ b/arch/x86/events/core.c
>> @@ -2578,3 +2578,34 @@ void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
>> cap->events_mask_len = x86_pmu.events_mask_len;
>> }
>> EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability);
>> +
>> +u64 perf_get_page_size(u64 virt)
>> +{
>> + unsigned long flags;
>> + unsigned int level;
>> + pte_t *pte;
>> +
>> + if (!virt)
>> + return 0;
>> +
>> + /*
>> + * Interrupts are disabled, so it prevents any tear down
>> + * of the page tables.
>> + * See the comment near struct mmu_table_batch.
>> + */
>> + local_irq_save(flags);
>> + if (virt >= TASK_SIZE)
>> + pte = lookup_address(virt, &level);
>> + else {
>> + if (current->mm) {
>> + pte = lookup_address_in_pgd(pgd_offset(current->mm, virt),
>> + virt, &level);
>> + } else
>> + level = PG_LEVEL_NUM;
>> + }
>> + local_irq_restore(flags);
>> + if (level >= PG_LEVEL_NUM)
>> + return 0;
>> +
>> + return (u64)page_level_size(level);
>> +}
>
> *sigh* there really isn't anything x86 specific there.
OK. I will split the patch and move the common code to a dedicated patch
in V5. I will try the proposed code and do some tests on X86.
> >> diff --git a/kernel/events/core.c b/kernel/events/core.c
>> index 236bb8d..d233f45 100644
>> --- a/kernel/events/core.c
>> +++ b/kernel/events/core.c
>> @@ -6352,6 +6358,12 @@ static u64 perf_virt_to_phys(u64 virt)
>> return phys_addr;
>> }
>>
>> +/* Return page size of given virtual address. IRQ-safe required. */
>> +u64 __weak perf_get_page_size(u64 virt)
>> +{
>> + return 0;
>> +}
>> +
>> static struct perf_callchain_entry __empty_callchain = { .nr = 0, };
>>
>> struct perf_callchain_entry *
>
> How about something like so instead?
>
> (completely untested, will likely make your grandma eat puppies
That's not funny!
Kan
prev parent reply other threads:[~2019-02-01 14:46 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-31 20:27 [PATCH V4 01/13] perf/core, x86: Add PERF_SAMPLE_DATA_PAGE_SIZE kan.liang
2019-01-31 20:27 ` [PATCH V4 02/13] perf tools: Support new sample type for data page size kan.liang
2019-01-31 20:27 ` [PATCH V4 03/13] perf script: Support " kan.liang
2019-01-31 20:27 ` [PATCH V4 04/13] perf sort: Add sort option for " kan.liang
2019-01-31 20:27 ` [PATCH V4 05/13] perf mem: Factor out a function to generate sort order kan.liang
2019-01-31 20:27 ` [PATCH V4 06/13] perf mem: Clean up output format kan.liang
2019-01-31 20:28 ` [PATCH V4 07/13] perf mem: Support data page size kan.liang
2019-01-31 20:28 ` [PATCH V4 08/13] perf test: Add test case for PERF_SAMPLE_DATA_PAGE_SIZE kan.liang
2019-01-31 20:28 ` [PATCH V4 09/13] perf/core, x86: Add support for PERF_SAMPLE_CODE_PAGE_SIZE kan.liang
2019-01-31 20:28 ` [PATCH V4 10/13] perf tools: " kan.liang
2019-01-31 20:28 ` [PATCH V4 11/13] perf script: " kan.liang
2019-01-31 20:28 ` [PATCH V4 12/13] perf report: " kan.liang
2019-01-31 20:28 ` [PATCH V4 13/13] perf test: Add test case " kan.liang
2019-02-01 9:22 ` [PATCH V4 01/13] perf/core, x86: Add PERF_SAMPLE_DATA_PAGE_SIZE Peter Zijlstra
2019-02-01 10:03 ` Peter Zijlstra
2019-02-01 10:36 ` Kirill A. Shutemov
2019-02-01 12:43 ` Peter Zijlstra
2019-02-01 12:47 ` Peter Zijlstra
2019-02-01 16:16 ` Liang, Kan
2019-02-04 10:54 ` Peter Zijlstra
2019-02-06 20:23 ` Liang, Kan
2019-02-01 10:34 ` Kirill A. Shutemov
2019-02-01 14:45 ` Liang, Kan [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=48363dcc-2047-e311-9da1-98b598a39df7@linux.intel.com \
--to=kan.liang@linux.intel.com \
--cc=acme@kernel.org \
--cc=ak@linux.intel.com \
--cc=eranian@google.com \
--cc=jolsa@redhat.com \
--cc=kirill@shutemov.name \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=vbabka@suse.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).