lkml.org 
[lkml]   [2016]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH V3 02/10] ras: acpi/apei: cper: generic error data entry v3 per ACPI 6.1
From
Date
Hello Russell,

Thank you for the feedback! Responses below


On 10/11/2016 12:52 PM, Russell King - ARM Linux wrote:
> On Fri, Oct 07, 2016 at 03:31:14PM -0600, Tyler Baicar wrote:
>> +static void cper_estatus_print_section_v300(const char *pfx,
>> + const struct acpi_hest_generic_data_v300 *gdata)
>> +{
>> + __u8 hour, min, sec, day, mon, year, century, *timestamp;
>> +
>> + if (gdata->validation_bits & ACPI_HEST_GEN_VALID_TIMESTAMP) {
>> + timestamp = (__u8 *)&(gdata->time_stamp);
>> + memcpy(&sec, timestamp, 1);
>> + memcpy(&min, timestamp + 1, 1);
>> + memcpy(&hour, timestamp + 2, 1);
>> + memcpy(&day, timestamp + 4, 1);
>> + memcpy(&mon, timestamp + 5, 1);
>> + memcpy(&year, timestamp + 6, 1);
>> + memcpy(&century, timestamp + 7, 1);
> This is utterly silly. Why are you using memcpy() to access individual
> bytes of a u8 pointer? What's wrong with:
>
> sec = timestamp[0];
> min = timestamp[1];
> hour = timestamp[2];
> day = timestamp[4];
> mon = timestamp[5];
> year = timestamp[6];
> century = timestamp[7];
>
> or even do the conversion here:
>
> sec = bcd2bin(timestamp[0]);
> ... etc ...
Yes, that will be a lot cleaner especially with moving the conversion here.
>
>> + printk("%stime: ", pfx);
>> + printk("%7s", 0x01 & *(timestamp + 3) ? "precise" : "");
>> + printk(" %02d:%02d:%02d %02d%02d-%02d-%02d\n",
>> + bcd2bin(hour), bcd2bin(min), bcd2bin(sec),
>> + bcd2bin(century), bcd2bin(year), bcd2bin(mon),
>> + bcd2bin(day));
>> + }
> It's also a good idea to (as much as possible) keep to single printk()
> statements - which makes the emission of the string more atomic wrt
> other CPUs and contexts. So, this should probably become (with the
> conversion being done at the assignment of sec etc):
>
> printk("%stime: %7s %02d:%02d:%02d %02d%02d-%02d-%02d\n",
> pfx, 0x01 & timestamp[3] ? "precise" : "",
> hour, min, sec, century, year, mon, day);
>
> which, IMHO, looks a lot nicer and doesn't risk some other printk()
> getting between each individual part of the line.
I will make this change in the next version. This printk does look a lot
nicer and avoids other prints from getting in the middle (I actually
just saw that happen in testing a couple days ago)
>> +}
>> +
>> static void cper_estatus_print_section(
>> - const char *pfx, const struct acpi_hest_generic_data *gdata, int sec_no)
>> + const char *pfx, struct acpi_hest_generic_data *gdata, int sec_no)
>> {
>> uuid_le *sec_type = (uuid_le *)gdata->section_type;
>> __u16 severity;
>> char newpfx[64];
>>
>> + if ((gdata->revision >> 8) >= 0x03)
>> + cper_estatus_print_section_v300(pfx,
>> + (const struct acpi_hest_generic_data_v300 *)gdata);
>> +
>> severity = gdata->error_severity;
>> printk("%s""Error %d, type: %s\n", pfx, sec_no,
>> cper_severity_str(severity));
> Not sure why you have the "" here - %sError works just as well and the
> "" is just obfuscation - the compiler will eliminate the double-double
> quote and merge the strings anyway.
>
I will remove the "" in the next version.

Thanks,
Tyler

--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.

\
 
 \ /
  Last update: 2016-10-13 00:19    [W:0.166 / U:0.608 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site