aboutsummaryrefslogtreecommitdiffstats
path: root/module/zfs/dataset_kstats.c
Commit message (Collapse)AuthorAgeFilesLines
* Introduce kmem_scnprintf()Richard Yao2022-10-291-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | `snprintf()` is meant to protect against buffer overflows, but operating on the buffer using its return value, possibly by calling it again, can cause a buffer overflow, because it will return how many characters it would have written if it had enough space even when it did not. In a number of places, we repeatedly call snprintf() by successively incrementing a buffer offset and decrementing a buffer length, by its return value. This is a potentially unsafe usage of `snprintf()` whenever the buffer length is reached. CodeQL complained about this. To fix this, we introduce `kmem_scnprintf()`, which will return 0 when the buffer is zero or the number of written characters, minus 1 to exclude the NULL character, when the buffer was too small. In all other cases, it behaves like snprintf(). The name is inspired by the Linux and XNU kernels' `scnprintf()`. The implementation was written before I thought to look at `scnprintf()` and had a good name for it, but it turned out to have identical semantics to the Linux kernel version. That lead to the name, `kmem_scnprintf()`. CodeQL only catches this issue in loops, so repeated use of snprintf() outside of a loop was not caught. As a result, a thorough audit of the codebase was done to examine all instances of `snprintf()` usage for potential problems and a few were caught. Fixes for them are included in this patch. Unfortunately, ZED is one of the places where `snprintf()` is potentially used incorrectly. Since using `kmem_scnprintf()` in it would require changing how it is linked, we modify its usage to make it safe, no matter what buffer length is used. In addition, there was a bug in the use of the return value where the NULL format character was not being written by pwrite(). That has been fixed. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Richard Yao <[email protected]> Closes #14098
* Add support for per dataset zil stats and use wmsum countersixhamza2022-07-201-14/+33
| | | | | | | | | | | | | | | | ZIL kstats are reported in an inclusive way, i.e., same counters are shared to capture all the activities happening in zil. Added support to report zil stats for every datset individually by combining them with already exposed dataset kstats. Wmsum uses per cpu counters and provide less overhead as compared to atomic operations. Updated zil kstats to replace wmsum counters to avoid atomic operations. Reviewed-by: Christian Schwarz <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Alexander Motin <[email protected]> Signed-off-by: Ameer Hamza <[email protected]> Closes #13636
* Replace dead opensolaris.org license linkTino Reichardt2022-07-111-1/+1
| | | | | | | | | The commit replaces all findings of the link: http://www.opensolaris.org/os/licensing with this one: https://opensource.org/licenses/CDDL-1.0 Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Tino Reichardt <[email protected]> Closes #13619
* Remove bcopy(), bzero(), bcmp()наб2022-03-151-1/+1
| | | | | | | | | | bcopy() has a confusing argument order and is actually a move, not a copy; they're all deprecated since POSIX.1-2001 and removed in -2008, and we shim them out to mem*() on Linux anyway Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Ahelenia Ziemiańska <[email protected]> Closes #12996
* Introduce write-mostly sumsAlexander Motin2021-05-271-24/+24
| | | | | | | | | | | | | | | | | | | | | wmsum counters are a reduced version of aggsum counters, optimized for write-mostly scenarios. They do not provide optimized read functions, but instead allow much cheaper add function. The primary usage is infrequently read statistic counters, not requiring exact precision. The Linux implementation is directly mapped into percpu_counter KPI. The FreeBSD implementation is directly mapped into counter(9) KPI. In user-space due to lack of better implementation mapped to aggsum. Unfortunately neither Linux percpu_counter nor FreeBSD counter(9) provide sufficient functionality to completelly replace aggsum, so it still remains to be used for several hot counters. Reviewed-by: Paul Dagnelie <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Ryan Moeller <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Sponsored-By: iXsystems, Inc. Closes #12114
* Fix panic on DilOS with kstat per dataset statisticsIgor K2019-09-031-0/+1
| | | | | | | | | | | Account for ZFS_MAX_DATASET_NAME_LEN in kstat data size. This value is ignored in the Linux kstat code but resolves the issue for other platforms. Reviewed-by: Serapheim Dimitropoulos <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Igor Kozhukhov <[email protected]> Closes #9254 Closes #9151
* port async unlinked drain from illumos-nexentaAlek P2019-02-121-0/+29
| | | | | | | | | | | | | | | | | This patch is an async implementation of the existing sync zfs_unlinked_drain() function. This function is called at mount time and is responsible for freeing znodes that we didn't get to freeing before. We don't have to hold mounting of the dataset until the unlinked list is fully drained as is done now. Since we can process the unlinked set asynchronously this results in a better user experience when mounting a dataset with entries in the unlinked set. Reviewed by: Jorgen Lundman <[email protected]> Reviewed by: Tom Caputi <[email protected]> Reviewed by: Brian Behlendorf <[email protected]> Reviewed-by: Matt Ahrens <[email protected]> Reviewed by: Paul Dagnelie <[email protected]> Signed-off-by: Alek Pinchuk <[email protected]> Closes #8142
* Introduce read/write kstats per datasetSerapheim Dimitropoulos2018-08-201-0/+185
The following patch introduces a few statistics on reads and writes grouped by dataset. These statistics are implemented as kstats (backed by aggregate sums for performance) and can be retrieved by using the dataset objset ID number. The motivation for this change is to provide some preliminary analytics on dataset usage/performance. Reviewed-by: Richard Elling <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Reviewed by: Matthew Ahrens <[email protected]> Signed-off-by: Serapheim Dimitropoulos <[email protected]> Closes #7705