user/sven/linux.git/include, branch v4.12.5

dentry name snapshots

2017-08-06T16:21:11Z

commit 49d31c2f389acfe83417083e1208422b4091cd9e upstream. take_dentry_name_snapshot() takes a safe snapshot of dentry name; if the name is a short one, it gets copied into caller-supplied structure, otherwise an extra reference to external name is grabbed (those are never modified). In either case the pointer to stable string is stored into the same structure. dentry must be held by the caller of take_dentry_name_snapshot(), but may be freely dropped afterwards - the snapshot will stay until destroyed by release_dentry_name_snapshot(). Intended use: struct name_snapshot s; take_dentry_name_snapshot(&s, dentry); ... access s.name ... release_dentry_name_snapshot(&s); Replaces fsnotify_oldname_...(), gets used in fsnotify to obtain the name to pass down with event. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

writeback: rework wb_[dec|inc]_stat family of functions

2017-07-27T22:10:23Z

commit 3e8f399da490e6ac20a3cfd6aa404c9aa961a9a2 upstream. Currently the writeback statistics code uses a percpu counters to hold various statistics. Furthermore we have 2 families of functions - those which disable local irq and those which doesn't and whose names begin with double underscore. However, they both end up calling __add_wb_stats which in turn calls percpu_counter_add_batch which is already irq-safe. Exploiting this fact allows to eliminated the __wb_* functions since they don't add any further protection than we already have. Furthermore, refactor the wb_* function to call __add_wb_stat directly without the irq-disabling dance. This will likely result in better runtime of code which deals with modifying the stat counters. While at it also document why percpu_counter_add_batch is in fact preempt and irq-safe since at least 3 people got confused. Link: http://lkml.kernel.org/r/1498029937-27293-1-git-send-email-nborisov@suse.com Signed-off-by: Nikolay Borisov Acked-by: Tejun Heo Reviewed-by: Jan Kara Cc: Josef Bacik Cc: Mel Gorman Cc: Jeff Layton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

percpu_counter: Rename __percpu_counter_add to percpu_counter_add_batch

2017-07-27T22:10:23Z

commit 104b4e5139fe384431ac11c3b8a6cf4a529edf4a upstream. Currently, percpu_counter_add is a wrapper around __percpu_counter_add which is preempt safe due to explicit calls to preempt_disable. Given how __ prefix is used in percpu related interfaces, the naming unfortunately creates the false sense that __percpu_counter_add is less safe than percpu_counter_add. In terms of context-safety, they're equivalent. The only difference is that the __ version takes a batch parameter. Make this a bit more explicit by just renaming __percpu_counter_add to percpu_counter_add_batch. This patch doesn't cause any functional changes. tj: Minor updates to patch description for clarity. Cosmetic indentation updates. Signed-off-by: Nikolay Borisov Signed-off-by: Tejun Heo Cc: Chris Mason Cc: Josef Bacik Cc: David Sterba Cc: Darrick J. Wong Cc: Jan Kara Cc: Jens Axboe Cc: linux-mm@kvack.org Cc: "David S. Miller" Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

sched/cputime: Accumulate vtime on top of nsec clocksource

2017-07-27T22:10:23Z

commit 2a42eb9594a1480b4ead9e036e06ee1290e5fa6d upstream. Currently the cputime source used by vtime is jiffies. When we cross a context boundary and jiffies have changed since the last snapshot, the pending cputime is accounted to the switching out context. This system works ok if the ticks are not aligned across CPUs. If they instead are aligned (ie: all fire at the same time) and the CPUs run in userspace, the jiffies change is only observed on tick exit and therefore the user cputime is accounted as system cputime. This is because the CPU that maintains timekeeping fires its tick at the same time as the others. It updates jiffies in the middle of the tick and the other CPUs see that update on IRQ exit: CPU 0 (timekeeper) CPU 1 ------------------- ------------- jiffies = N ... run in userspace for a jiffy tick entry tick entry (sees jiffies = N) set jiffies = N + 1 tick exit tick exit (sees jiffies = N + 1) account 1 jiffy as stime Fix this with using a nanosec clock source instead of jiffies. The cputime is then accumulated and flushed everytime the pending delta reaches a jiffy in order to mitigate the accounting overhead. [ fweisbec: changelog, rebase on struct vtime, field renames, add delta on cputime readers, keep idle vtime as-is (low overhead accounting), harmonize clock sources. ] Suggested-by: Thomas Gleixner Reported-by: Luiz Capitulino Tested-by: Luiz Capitulino Signed-off-by: Wanpeng Li Signed-off-by: Frederic Weisbecker Reviewed-by: Thomas Gleixner Acked-by: Rik van Riel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1498756511-11714-6-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

sched/cputime: Move the vtime task fields to their own struct

2017-07-27T22:10:23Z

commit bac5b6b6b11560f323e71d0ebac4061cfe5f56c0 upstream. We are about to add vtime accumulation fields to the task struct. Let's avoid more bloatification and gather vtime information to their own struct. Tested-by: Luiz Capitulino Signed-off-by: Frederic Weisbecker Reviewed-by: Thomas Gleixner Acked-by: Rik van Riel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1498756511-11714-5-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

sched/cputime: Rename vtime fields

2017-07-27T22:10:22Z

commit 60a9ce57e7c5ac1df3a39fb941022bbfa40c0862 upstream. The current "snapshot" based naming on vtime fields suggests we record some past event but that's a low level picture of their actual purpose which comes out blurry. The real point of these fields is to run a basic state machine that tracks down cputime entry while switching between contexts. So lets reflect that with more meaningful names. Tested-by: Luiz Capitulino Signed-off-by: Frederic Weisbecker Reviewed-by: Thomas Gleixner Acked-by: Rik van Riel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1498756511-11714-4-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

vtime, sched/cputime: Remove vtime_account_user()

2017-07-27T22:10:22Z

commit 1c3eda01a79b8e9237d91c52c5a75b20983f47c6 upstream. It's an unnecessary function between vtime_user_exit() and account_user_time(). Tested-by: Luiz Capitulino Signed-off-by: Frederic Weisbecker Reviewed-by: Thomas Gleixner Acked-by: Rik van Riel Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1498756511-11714-2-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Mel Gorman Signed-off-by: Greg Kroah-Hartman

vfio: New external user group/file match

2017-07-27T22:10:16Z

commit 5d6dee80a1e94cc284d03e06d930e60e8d3ecf7d upstream. At the point where the kvm-vfio pseudo device wants to release its vfio group reference, we can't always acquire a new reference to make that happen. The group can be in a state where we wouldn't allow a new reference to be added. This new helper function allows a caller to match a file to a group to facilitate this. Given a file and group, report if they match. Thus the caller needs to already have a group reference to match to the file. This allows the deletion of a group without acquiring a new reference. Signed-off-by: Alex Williamson Reviewed-by: Eric Auger Reviewed-by: Paolo Bonzini Tested-by: Eric Auger Signed-off-by: Greg Kroah-Hartman

PCI/MSI: Ignore affinity if pre/post vector count is more than min_vecs

2017-07-27T22:10:09Z

commit 6f9a22bc5775d231ab8fbe2c2f3c88e45e3e7c28 upstream. min_vecs is the minimum amount of vectors needed to operate in MSI-X mode which may just include the vectors that don't need affinity. Disabling affinity settings causes the qla2xxx driver scsi_add_host() to fail when blk_mq is enabled as the blk_mq_pci_map_queues() expects affinity masks on each vector. Fixes: dfef358bd1be ("PCI/MSI: Don't apply affinity if there aren't enough vectors left") Signed-off-by: Michael Hernandez Signed-off-by: Himanshu Madhani Signed-off-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman

iscsi-target: Add login_keys_workaround attribute for non RFC initiators

2017-07-27T22:10:08Z

commit 138d351eefb727ab9e41a3dc5f112ceb4f6e59f2 upstream. This patch re-introduces part of a long standing login workaround that was recently dropped by: commit 1c99de981f30b3e7868b8d20ce5479fa1c0fea46 Author: Nicholas Bellinger Date: Sun Apr 2 13:36:44 2017 -0700 iscsi-target: Drop work-around for legacy GlobalSAN initiator Namely, the workaround for FirstBurstLength ended up being required by Mellanox Flexboot PXE boot ROMs as reported by Robert. So this patch re-adds the work-around for FirstBurstLength within iscsi_check_proposer_for_optional_reply(), and makes the key optional to respond when the initiator does not propose, nor respond to it. Also as requested by Arun, this patch introduces a new TPG attribute named 'login_keys_workaround' that controls the use of both the FirstBurstLength workaround, as well as the two other existing workarounds for gPXE iSCSI boot client. By default, the workaround is enabled with login_keys_workaround=1, since Mellanox FlexBoot requires it, and Arun has verified the Qlogic MSFT initiator already proposes FirstBurstLength, so it's uneffected by this re-adding this part of the original work-around. Reported-by: Robert LeBlanc Cc: Robert LeBlanc Reviewed-by: Arun Easi Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman