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path: root/drivers/scsi/fnic/fnic_trace.c
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2023-12-13scsi: fnic: Define stats to track multiqueue (MQ) IOsKaran Tilak Kumar
Define an array to track IOs for the different queues, print the IO stats in fnic get stats data. Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com> Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com> Link: https://lore.kernel.org/r/20231211173617.932990-9-kartilak@cisco.com Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-07-05scsi: fnic: Use vmalloc_array() and vcalloc()Julia Lawall
Use vmalloc_array() and vcalloc() to protect against multiplication overflows. The changes were done using the following Coccinelle semantic patch: // <smpl> @initialize:ocaml@ @@ let rename alloc = match alloc with "vmalloc" -> "vmalloc_array" | "vzalloc" -> "vcalloc" | _ -> failwith "unknown" @@ size_t e1,e2; constant C1, C2; expression E1, E2, COUNT, x1, x2, x3; typedef u8; typedef __u8; type t = {u8,__u8,char,unsigned char}; identifier alloc = {vmalloc,vzalloc}; fresh identifier realloc = script:ocaml(alloc) { rename alloc }; @@ ( alloc(x1*x2*x3) | alloc(C1 * C2) | alloc((sizeof(t)) * (COUNT), ...) | - alloc((e1) * (e2)) + realloc(e1, e2) | - alloc((e1) * (COUNT)) + realloc(COUNT, e1) | - alloc((E1) * (E2)) + realloc(E1, E2) ) // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/20230627144339.144478-8-Julia.Lawall@inria.fr Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2023-03-16scsi: fnic: Switch to use %ptTsAndy Shevchenko
Use %ptTs instead of open-coded variant to print contents of time64_t type in human readable form. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20230314145813.66112-1-andriy.shevchenko@linux.intel.com Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-10treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE ↵Thomas Gleixner
(part 1) Based on the normalized pattern: this program is free software you may redistribute it and/or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license the software is provided as is without warranty of any kind express or implied including but not limited to the warranties of merchantability fitness for a particular purpose and noninfringement in no event shall the authors or copyright holders be liable for any claim damages or other liability whether in an action of contract tort or otherwise arising from out of or in connection with the software or the use or other dealings in the software extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-18scsi: fnic: Rudimentary spelling fixesBhaskar Chowdhury
Rudimentary typo fixes throughout the fnic_trace.c file. Link: https://lore.kernel.org/r/20210317092240.927822-1-unixbhaskar@gmail.com Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-03-17scsi: fnic: Use scnprintf() for avoiding potential buffer overflowTakashi Iwai
Since snprintf() returns the would-be-output size instead of the actual output size, the succeeding calls may go beyond the given buffer limit. Fix it by replacing with scnprintf(). Link: https://lore.kernel.org/r/20200315094241.9086-4-tiwai@suse.de Cc: "James E . J . Bottomley" <jejb@linux.ibm.com> Cc: "Martin K . Petersen" <martin.petersen@oracle.com> Cc: Satish Kharat <satishkh@cisco.com> Cc: Sesidhar Baddela <sebaddel@cisco.com> Cc: Karan Tilak Kumar <kartilak@cisco.com> Cc: linux-scsi@vger.kernel.org Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-08-30scsi: fnic: print port speed only at driver init or speed changeJohn Pittman
Port speed printing was added by commit d948e6383ec3 ("scsi: fnic: Add port speed stat to fnic debug stats"). As currently configured, this will cause the port speed to be printed to syslog every 2 seconds. To prevent log spamming, only print the vnic port speed at driver initialization and if the speed changes. Also clean up a small typo in fnic_trace.c. Fixes: d948e6383ec3 ("scsi: fnic: Add port speed stat to fnic debug stats") Signed-off-by: John Pittman <jpittman@redhat.com> Reviewed-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-01-29scsi: fnic: no need to check return value of debugfs_create functionsGreg Kroah-Hartman
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Satish Kharat <satishkh@cisco.com> Cc: Sesidhar Baddela <sebaddel@cisco.com> Cc: Karan Tilak Kumar <kartilak@cisco.com> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: linux-scsi@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-01-22scsi: fnic: fnic stats for max CQs processed and ISR timeSatish Kharat
This change is to add fnic stats for the max number of CQs (corresponding to copy WQ) processed in a given interrupt, max time taken by the ISR. Signed-off-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-01-22scsi: fnic: Add port speed stat to fnic debug statsSatish Kharat
This patch adds the current fnic port speed stat to fnic debug stats. Signed-off-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07scsi: fnic: Use vzallocSabyasachi Gupta
Replaced vmalloc + memset with vzalloc Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com> Acked-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-06-12treewide: Use array_size() in vmalloc()Kees Cook
The vmalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vmalloc(a * b) with: vmalloc(array_size(a, b)) as well as handling cases of: vmalloc(a * b * c) with: vmalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vmalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vmalloc( - sizeof(u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vmalloc( - sizeof(char) * COUNT + COUNT , ...) | vmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vmalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vmalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vmalloc(C1 * C2 * C3, ...) | vmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vmalloc(C1 * C2, ...) | vmalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-04-18scsi: fnic: fix spelling mistake in fnic stats "Abord" -> "Abort"Colin Ian King
Trivial fix to spelling mistake in fnic stats message text. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-01-22scsi: fnic: use 64-bit timestampsArnd Bergmann
struct timespec is deprecated since it overflows in 2038 on 32-bit architectures, so we should use timespec64 consistently. I'm slightly adapting the format strings here, to make sure we print the nanoseconds with the correct number of leading zeroes. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-06-27scsi: fnic: added timestamp reporting in fnic debug statsSatish Kharat
Added the timestamps for 1. current timestamp 2. last fnic stats read timestamp 3. last fnic stats reset timestamp and the deltas since last stats read and last reset in fnic stats. fnic stats uses debugfs Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-03-23scsi: fnic: Adding debug IO and Abort latency counter to fnic statsSatish Kharat
The IO and Abort latency counter counts the time taken to complete the IO and abort command into broad buckets. This is not intended for performance measurement, just a debug statistic. current_max_io_time tries to keep track of the maximum time an IO has taken to complete if it is > 30sec. Signed-off-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-03-23scsi: fnic: Adding Check Condition counter to misc fnicstatsSatish Kharat
Just a simple counter of number of check conditions encountered on that host. Signed-off-by: Satish Kharat <satishkh@cisco.com> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08scsi: fnic: Use time64_t to represent trace timestampsDeepa Dinamani
Trace timestamps use struct timespec and CURRENT_TIME which are not y2038 safe. These timestamps are only part of the trace log on the machine and are not shared with the fnic. Replace then with y2038 safe struct timespec64 and ktime_get_real_ts64(), respectively. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Cc: Hiral Patel <hiralpat@cisco.com> Cc: Suma Ramars <sramars@cisco.com> Cc: Brian Uchino <buchino@cisco.com> Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: linux-scsi@vger.kernel.org Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-06-03x86/mm: Decouple <linux/vmalloc.h> from <asm/io.h>Stephen Rothwell
Nothing in <asm/io.h> uses anything from <linux/vmalloc.h>, so remove it from there and fix up the resulting build problems triggered on x86 {64|32}-bit {def|allmod|allno}configs. The breakages were triggering in places where x86 builds relied on vmalloc() facilities but did not include <linux/vmalloc.h> explicitly and relied on the implicit inclusion via <asm/io.h>. Also add: - <linux/init.h> to <linux/io.h> - <asm/pgtable_types> to <asm/io.h> ... which were two other implicit header file dependencies. Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [ Tidied up the changelog. ] Acked-by: David Miller <davem@davemloft.net> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Vinod Koul <vinod.koul@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Colin Cross <ccross@android.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: James E.J. Bottomley <JBottomley@odin.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Kristen Carlson Accardi <kristen@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Suma Ramars <sramars@cisco.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-20Fnic: Memcopy only mimumum of data or trace bufferHiral Shah
In case of receive path, we do not have eth header or fcoe header available when we take a trace so we fill the fc trace buffer with 0xff for both values. We copy only mimimum of received data or trace buffer size - fc header - eth and fcoe header - Increment fnic version from 1.6.0.12 to 1.6.0.13 Signed-off-by: Hiral Shah <hishah@cisco.com> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Anil Chintalapati <achintal@cisco.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-07Merge tag 'scsi-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI updates from James Bottomley: "This patch set consists of the usual driver updates (megaraid_sas, arcmsr, be2iscsi, lpfc, mpt2sas, mpt3sas, qla2xxx, ufs) plus several assorted fixes and miscellaneous updates (including the pci_msix_enable_range() changes that have been pending for a while)" * tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (202 commits) scsi: add a CONFIG_SCSI_MQ_DEFAULT option ufs: definitions for phy interface ufs: tune bkops while power managment events ufs: Add support for clock scaling using devfreq framework ufs: Add freq-table-hz property for UFS device ufs: Add support for clock gating ufs: refactor configuring power mode ufs: add UFS power management support ufs: introduce well known logical unit in ufs ufs: manually add well known logical units ufs: Active Power Mode - configuring bActiveICCLevel ufs: improve init sequence ufs: refactor query descriptor API support ufs: add voting support for host controller power ufs: Add clock initialization support ufs: Add regulator enable support ufs: Allow vendor specific initialization scsi: don't add scsi_device if its already visible scsi: fix the type for well known LUs scsi: fix comment in struct Scsi_Host definition ...
2014-09-16fnic: assign FIP_ALL_FCF_MACS to fcoe_all_fcfsHiral Shah
1) Assgning FIP_ALL_FCF_MACS to fcoe_all_fcfs allows VLAN request to be sent to correct Mac address for VLAN Discovery otherwise VLAN request will be sent to invalid address hence FLOGI never happens. 2) Simplify the copy_and_format_trace_data code and log the correct Link event for fnic control path tracing in case of link status UP->UP. 3) Increment Fnic driver version Signed-off-by: Hiral Shah <hishah@cisco.com> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-09-01treewide: fix errors in printkMasanari Iida
This patch fix spelling typo in printk. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-05-19fnic: fnic Control Path Trace UtilityHiral Shah
Fnic Ctlr Path Trace utility is a tracing functionality built directly into fnic driver to trace the control path frames like discovery, FLOGI request/reply, PLOGI request/reply, link event etc. It will be one trace file for all fnics. It will help us to debug and resolve the discovery and initialization related issues in more convenient way. This trace information includes time stamp, Host Number, Frame type, Frame Length and Frame. By default,64 pages are allocated but we can change the number of allocated pages by module parameter fnic_fc_trace_max_page. Each entry is of 256 byte and available entries are depends on allocated number of pages. We can turn on or off the fnic control path trace functionality by module paramter fc_trace_enable and/or reset the trace contain by module paramter fc_trace_clear. Signed-off-by: Hiral Shah <hishah@cisco.com> Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2013-10-25[SCSI] fnic: Fnic Statistics CollectionHiral Patel
This feature gathers active and cumulative per fnic stats for io, abort, terminate, reset, vlan discovery path and it also includes various important stats for debugging issues. It also provided debugfs and ioctl interface for user to retrieve these stats. It also provides functionality to reset cumulative stats through user interface. Signed-off-by: Hiral Patel <hiralpat@cisco.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-02-22[SCSI] fnic: Fnic Trace UtilityHiral Patel
Fnic Trace utility is a tracing functionality built directly into fnic driver to trace events. The benefit that trace buffer brings to fnic driver is the ability to see what it happening inside the fnic driver. It also provides the capability to trace every IO event inside fnic driver to debug panics, hangs and potentially IO corruption issues. This feature makes it easy to find problems in fnic driver and it also helps in tracking down strange bugs in a more manageable way. Trace buffer is shared across all fnic instances for this implementation. Signed-off-by: Hiral Patel <hiralpat@cisco.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>