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Date: Thu, 10 Jul 2014 20:44:16 +0200 From: Borislav Petkov <bp@...en8.de> To: Havard Skinnemoen <hskinnemoen@...gle.com> Cc: Tony Luck <tony.luck@...el.com>, Linux Kernel <linux-kernel@...r.kernel.org>, Ewout van Bekkum <ewout@...gle.com> Subject: Re: [PATCH 4/6] x86-mce: Add spinlocks to prevent duplicated MCP and CMCI reports. On Thu, Jul 10, 2014 at 11:03:43AM -0700, Havard Skinnemoen wrote: > For non-shared banks, we might risk some CPUs not being able to > poll their banks in a long time if they happen to be more or less > synchronized with a different CPU. This will also get worse with > shorter polling intervals, and with larger numbers of CPUs. No, I meant to do something like if (atomic_dec_and_test(&mce_banks[i].poll)) m.status = mce_rdmsrl(MSR_IA32_MCx_STATUS(i)); atomic_add_unless(&mce_banks[i].poll, 1, 1); so that you have only one CPU read the status register of mce_banks[i]. For non-shared banks, this will always work because no other CPU will dec that variable anyway. Or am I missing something...? -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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