From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760881Ab2EKRHL (ORCPT ); Fri, 11 May 2012 13:07:11 -0400 Received: from s15943758.onlinehome-server.info ([217.160.130.188]:34769 "EHLO mail.x86-64.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760817Ab2EKRHC (ORCPT ); Fri, 11 May 2012 13:07:02 -0400 Date: Fri, 11 May 2012 19:06:47 +0200 From: Borislav Petkov To: Mauro Carvalho Chehab Cc: Linux Edac Mailing List , Linux Kernel Mailing List , Doug Thompson , Steven Rostedt , Frederic Weisbecker , Ingo Molnar Subject: Re: [PATCH v.23-2] RAS: use tracepoint to handle hw issues Message-ID: <20120511170647.GA17299@aftab.osrc.amd.com> References: <1336683628-12954-1-git-send-email-mchehab@redhat.com> <1336748054-21325-1-git-send-email-mchehab@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1336748054-21325-1-git-send-email-mchehab@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>From Documentation/SubmittingPatches: "2) Describe your changes. Describe the technical detail of the change(s) your patch includes. Be as specific as possible." "use tracepoint to handle hw issues" is not specific - it is bullshit bingo with a random word generator. I'm getting tired of this crap: either take the suggestion as is, without randomly changing it for no reason whatsoever, or give a good reason why it is not a good suggestion and propose a better one! Randomly changing it in the next version of the patch for another, even crappier one doesn't help. On Fri, May 11, 2012 at 11:54:14AM -0300, Mauro Carvalho Chehab wrote: > Add a new tracepoint-based hardware events report method for > reporting Memory Controller events. > > Part of the description bellow is shamelessly copied from Tony > Luck's notes about the Hardware Error BoF during LPC 2010 [1]. > Tony, thanks for your notes and discussions to generate the > h/w error reporting requirements. > > [1] http://lwn.net/Articles/416669/ > > We have several subsystems & methods for reporting hardware errors: > > 1) EDAC ("Error Detection and Correction"). In its original form > this consisted of a platform specific driver that read topology > information and error counts from chipset registers and reported > the results via a sysfs interface. > > 2) mcelog - x86 specific decoding of machine check bank registers > reporting in binary form via /dev/mcelog. Recent additions make use > of the APEI extensions that were documented in version 4.0a of the > ACPI specification to acquire more information about errors without > having to rely reading chipset registers directly. A user level > programs decodes into somewhat human readable format. > > 3) drivers/edac/mce_amd.c - this driver hooks into the mcelog path and > decodes errors reported via machine check bank registers in AMD > processors to the console log using printk(); > > Each of these mechanisms has a band of followers ... and none > of them appear to meet all the needs of all users. > > As part of a RAS subsystem, let's encapsulate the memory error hardware > events into a trace facility. > > The tracepoint printk will be displayed like: > > mc_event: (Corrected|Uncorrected|Fatal) error:[error msg] on memory stick "[label]" ([location] [edac_mc detail] [driver_detail]) > > Where: > [error msg] is the driver-specific error message > (e. g. "memory read", "bus error", ...); > [location] is the location in terms of memory controller and > branch/channel/slot, channel/slot or csrow/channel; > [label] is the memory stick label; > [edac_mc detail] describes the address location of the error > and the syndrome; > [driver detail] is driver-specifig error message details, > when needed/provided (e. g. "area:DMA", ...) > > For example: > > mc_event: Corrected error:memory read on memory stick "DIMM_1A" (mc:0 channel:0 slot:0 page:0x586b6e offset:0xa66 grain:32 syndrome:0x0 area:DMA) > > Of course, any userspace tools meant to handle errors should not parse > the above data. They should, instead, use the binary fields provided by > the tracepoint, mapping them directly into their MIBs. > > NOTE: The original patch was providing an additional mechanism for > MCA-based trace events that also contained MCA error register data. > Hoever, as no agreement was reached so far for the MCA-based trace > events, for now, let's add events only for memory errors. > A latter patch is planned to change the tracepoint, for those types > of event. > > Reviewed-by: Aristeu Rozanski > Cc: Doug Thompson > Cc: Steven Rostedt > Cc: Frederic Weisbecker > Cc: Ingo Molnar > Signed-off-by: Mauro Carvalho Chehab > --- > drivers/edac/edac_core.h | 2 +- > drivers/edac/edac_mc.c | 25 ++++++++++---- > include/ras/ras_event.h | 78 ++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 97 insertions(+), 8 deletions(-) > create mode 100644 include/ras/ras_event.h > > diff --git a/drivers/edac/edac_core.h b/drivers/edac/edac_core.h > index f06ce9a..eee7360 100644 > --- a/drivers/edac/edac_core.h > +++ b/drivers/edac/edac_core.h > @@ -468,7 +468,7 @@ void edac_mc_handle_error(const enum hw_event_mc_err_type type, > const int layer2, > const char *msg, > const char *other_detail, > - const void *mcelog); > + const void *arch_log); > > /* > * edac_device APIs > diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c > index e5b5563..0153cd98 100644 > --- a/drivers/edac/edac_mc.c > +++ b/drivers/edac/edac_mc.c > @@ -33,6 +33,10 @@ > #include "edac_core.h" > #include "edac_module.h" > > +#define CREATE_TRACE_POINTS > +#define TRACE_INCLUDE_PATH ../../include/ras > +#include > + > /* lock to memory controller's control array */ > static DEFINE_MUTEX(mem_ctls_mutex); > static LIST_HEAD(mc_devices); > @@ -381,6 +385,7 @@ struct mem_ctl_info *edac_mc_alloc(unsigned mc_num, > * which will perform kobj unregistration and the actual free > * will occur during the kobject callback operation > */ > + > return mci; > } > EXPORT_SYMBOL_GPL(edac_mc_alloc); > @@ -982,7 +987,7 @@ void edac_mc_handle_error(const enum hw_event_mc_err_type type, > const int layer2, > const char *msg, > const char *other_detail, > - const void *mcelog) > + const void *arch_log) > { > /* FIXME: too much for stack: move it to some pre-alocated area */ > char detail[80], location[80]; > @@ -1119,21 +1124,27 @@ void edac_mc_handle_error(const enum hw_event_mc_err_type type, > } > > /* Memory type dependent details about the error */ > - if (type == HW_EVENT_ERR_CORRECTED) { > + if (type == HW_EVENT_ERR_CORRECTED) > snprintf(detail, sizeof(detail), > "page:0x%lx offset:0x%lx grain:%d syndrome:0x%lx", > page_frame_number, offset_in_page, > grain, syndrome); > - edac_ce_error(mci, pos, msg, location, label, detail, > - other_detail, enable_per_layer_report, > - page_frame_number, offset_in_page, grain); > - } else { > + else > snprintf(detail, sizeof(detail), > "page:0x%lx offset:0x%lx grain:%d", > page_frame_number, offset_in_page, grain); > > + /* Report the error via the trace interface */ > + trace_mc_event(type, mci->mc_idx, msg, label, location, > + detail, other_detail); > + > + /* Report the error via the edac_mc_printk() interface */ > + if (type == HW_EVENT_ERR_CORRECTED) > + edac_ce_error(mci, pos, msg, location, label, detail, > + other_detail, enable_per_layer_report, > + page_frame_number, offset_in_page, grain); > + else > edac_ue_error(mci, pos, msg, location, label, detail, > other_detail, enable_per_layer_report); > - } > } > EXPORT_SYMBOL_GPL(edac_mc_handle_error); > diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h > new file mode 100644 > index 0000000..66f6a43 > --- /dev/null > +++ b/include/ras/ras_event.h > @@ -0,0 +1,78 @@ > +#undef TRACE_SYSTEM > +#define TRACE_SYSTEM ras > +#define TRACE_INCLUDE_FILE ras_event > + > +#if !defined(_TRACE_HW_EVENT_MC_H) || defined(TRACE_HEADER_MULTI_READ) > +#define _TRACE_HW_EVENT_MC_H > + > +#include > +#include > +#include > + > +/* > + * Hardware Events Report > + * > + * Those events are generated when hardware detected a corrected or > + * uncorrected event, and are meant to replace the current API to report > + * errors defined on both EDAC and MCE subsystems. > + * > + * FIXME: Add events for handling memory errors originated from the > + * MCE subsystem. > + */ > + > +/* > + * Hardware-independent Memory Controller specific events > + */ > + > +/* > + * Default error mechanisms for Memory Controller errors (CE and UE) > + */ > +TRACE_EVENT(mc_event, > + > + TP_PROTO(const unsigned int err_type, > + const unsigned int mc_index, > + const char *error_msg, > + const char *label, > + const char *location, > + const char *core_detail, > + const char *driver_detail), > + > + TP_ARGS(err_type, mc_index, error_msg, label, location, > + core_detail, driver_detail), > + > + TP_STRUCT__entry( > + __field( unsigned int, err_type ) > + __field( unsigned int, mc_index ) > + __string( msg, error_msg ) > + __string( label, label ) > + __string( detail, core_detail ) > + __string( location, location ) > + __string( driver_detail, driver_detail ) > + ), > + > + TP_fast_assign( > + __entry->err_type = err_type; > + __entry->mc_index = mc_index; > + __assign_str(msg, error_msg); > + __assign_str(label, label); > + __assign_str(location, location); > + __assign_str(detail, core_detail); > + __assign_str(driver_detail, driver_detail); > + ), > + > + TP_printk("%s error:%s on memory stick \"%s\" (mc:%d %s %s %s)", > + (__entry->err_type == HW_EVENT_ERR_CORRECTED) ? "Corrected" : > + ((__entry->err_type == HW_EVENT_ERR_FATAL) ? > + "Fatal" : "Uncorrected"), > + __get_str(msg), > + __get_str(label), > + __entry->mc_index, > + __get_str(location), > + __get_str(detail), > + __get_str(driver_detail)) > +); > + > +#endif /* _TRACE_HW_EVENT_MC_H */ > + > +/* This part must be outside protection */ > +#include > -- > 1.7.8 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-edac" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551