From: Daniel Axtens <dja@axtens•net>
To: Anshuman Khandual <khandual@linux•vnet.ibm.com>
Cc: linuxppc-dev@ozlabs•org, mikey@neuling•org, sukadev@linux•vnet.ibm.com
Subject: Re: [PATCH V8 03/10] powerpc, perf: Re organize BHRB processing
Date: Wed, 10 Jun 2015 14:36:16 +1000 [thread overview]
Message-ID: <1433910976.3096.26.camel@axtens.net> (raw)
In-Reply-To: <1433763511-5270-3-git-send-email-khandual@linux.vnet.ibm.com>
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> +void update_branch_entry(struct cpu_hw_events *cpuhw,
> + int index, u64 from, u64 to, int pred)
> +{
> + cpuhw->bhrb_entries[index].from = from;
> + cpuhw->bhrb_entries[index].to = to;
> + cpuhw->bhrb_entries[index].mispred = pred;
> + cpuhw->bhrb_entries[index].predicted = ~pred;
> +}
I realise you're copying existing code, but:
- could you please rename pred? If we assign .mispred to pred
and .predicted to ~pred, we should pick a different name for pred.
- I'm really uncomfortable with the bitwise inverting a signed integer.
Can you explain what is going on here? Looking at
include/uapi/linux/perf_event.h, this seems to be a single bit flag:
shouldn't this then be a logical flip rather than a bitwise one?
(Furthermore, looking at that header, why is pred an int at all? Why not
a bool?)
> +
> /* Processing BHRB entries */
> static void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw)
> {
> - u64 val;
> - u64 addr;
> + u64 val, addr, tmp;
Please don't use 'tmp' here. As far as I can tell, you use this variable
to compute the 'to' address. The name should reflect that.
Regards,
Daniel
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next prev parent reply other threads:[~2015-06-10 4:37 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-08 11:38 [PATCH V8 01/10] powerpc, perf: Drop the branch sample when 'from' cannot be fetched Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 02/10] powerpc, perf: Restore privillege level filter support for BHRB Anshuman Khandual
2015-06-10 3:43 ` Daniel Axtens
2015-06-10 12:08 ` Anshuman Khandual
2015-06-11 3:28 ` Daniel Axtens
2015-06-12 7:06 ` Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 03/10] powerpc, perf: Re organize BHRB processing Anshuman Khandual
2015-06-10 4:36 ` Daniel Axtens [this message]
2015-06-10 12:09 ` Anshuman Khandual
2015-06-11 3:32 ` Daniel Axtens
2015-06-12 7:05 ` Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 04/10] powerpc, perf: Re organize PMU based branch filter processing in POWER8 Anshuman Khandual
2015-06-10 5:07 ` Daniel Axtens
2015-06-10 12:09 ` Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 05/10] powerpc, perf: Change the name of HW PMU branch filter tracking variable Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 06/10] powerpc, lib: Add new branch analysis support functions Anshuman Khandual
2015-06-10 5:33 ` Daniel Axtens
2015-06-10 12:10 ` Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 07/10] powerpc, perf: Enable SW filtering in branch stack sampling framework Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 08/10] powerpc, perf: Change POWER8 PMU configuration to work with SW filters Anshuman Khandual
2015-06-10 5:49 ` Daniel Axtens
2015-06-10 12:10 ` Anshuman Khandual
2015-06-11 3:38 ` Daniel Axtens
2015-06-08 11:38 ` [PATCH V8 09/10] powerpc, perf: Enable privilege mode SW branch filters Anshuman Khandual
2015-06-11 1:19 ` Daniel Axtens
2015-06-12 7:04 ` Anshuman Khandual
2015-06-08 11:38 ` [PATCH V8 10/10] selftests, powerpc: Add test for BHRB branch filters (HW & SW) Anshuman Khandual
2015-06-09 5:41 ` Anshuman Khandual
2015-06-11 2:09 ` Daniel Axtens
2015-06-12 7:02 ` Anshuman Khandual
2015-06-12 7:26 ` Madhavan Srinivasan
2015-06-12 8:59 ` Anshuman Khandual
2015-06-10 3:21 ` [PATCH V8 01/10] powerpc, perf: Drop the branch sample when 'from' cannot be fetched Daniel Axtens
2015-06-10 12:02 ` Anshuman Khandual
2015-06-11 2:22 ` Daniel Axtens
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