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14 commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
|
6c4aa896eb |
Performance events changes for v6.14:
- Seqlock optimizations that arose in a perf context and were
merged into the perf tree:
- seqlock: Add raw_seqcount_try_begin (Suren Baghdasaryan)
- mm: Convert mm_lock_seq to a proper seqcount ((Suren Baghdasaryan)
- mm: Introduce mmap_lock_speculate_{try_begin|retry} (Suren Baghdasaryan)
- mm/gup: Use raw_seqcount_try_begin() (Peter Zijlstra)
- Core perf enhancements:
- Reduce 'struct page' footprint of perf by mapping pages
in advance (Lorenzo Stoakes)
- Save raw sample data conditionally based on sample type (Yabin Cui)
- Reduce sampling overhead by checking sample_type in
perf_sample_save_callchain() and perf_sample_save_brstack() (Yabin Cui)
- Export perf_exclude_event() (Namhyung Kim)
- Uprobes scalability enhancements: (Andrii Nakryiko)
- Simplify find_active_uprobe_rcu() VMA checks
- Add speculative lockless VMA-to-inode-to-uprobe resolution
- Simplify session consumer tracking
- Decouple return_instance list traversal and freeing
- Ensure return_instance is detached from the list before freeing
- Reuse return_instances between multiple uretprobes within task
- Guard against kmemdup() failing in dup_return_instance()
- AMD core PMU driver enhancements:
- Relax privilege filter restriction on AMD IBS (Namhyung Kim)
- AMD RAPL energy counters support: (Dhananjay Ugwekar)
- Introduce topology_logical_core_id() (K Prateek Nayak)
- Remove the unused get_rapl_pmu_cpumask() function
- Remove the cpu_to_rapl_pmu() function
- Rename rapl_pmu variables
- Make rapl_model struct global
- Add arguments to the init and cleanup functions
- Modify the generic variable names to *_pkg*
- Remove the global variable rapl_msrs
- Move the cntr_mask to rapl_pmus struct
- Add core energy counter support for AMD CPUs
- Intel core PMU driver enhancements:
- Support RDPMC 'metrics clear mode' feature (Kan Liang)
- Clarify adaptive PEBS processing (Kan Liang)
- Factor out functions for PEBS records processing (Kan Liang)
- Simplify the PEBS records processing for adaptive PEBS (Kan Liang)
- Intel uncore driver enhancements: (Kan Liang)
- Convert buggy pmu->func_id use to pmu->registered
- Support more units on Granite Rapids
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2025-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull performance events updates from Ingo Molnar:
"Seqlock optimizations that arose in a perf context and were merged
into the perf tree:
- seqlock: Add raw_seqcount_try_begin (Suren Baghdasaryan)
- mm: Convert mm_lock_seq to a proper seqcount (Suren Baghdasaryan)
- mm: Introduce mmap_lock_speculate_{try_begin|retry} (Suren
Baghdasaryan)
- mm/gup: Use raw_seqcount_try_begin() (Peter Zijlstra)
Core perf enhancements:
- Reduce 'struct page' footprint of perf by mapping pages in advance
(Lorenzo Stoakes)
- Save raw sample data conditionally based on sample type (Yabin Cui)
- Reduce sampling overhead by checking sample_type in
perf_sample_save_callchain() and perf_sample_save_brstack() (Yabin
Cui)
- Export perf_exclude_event() (Namhyung Kim)
Uprobes scalability enhancements: (Andrii Nakryiko)
- Simplify find_active_uprobe_rcu() VMA checks
- Add speculative lockless VMA-to-inode-to-uprobe resolution
- Simplify session consumer tracking
- Decouple return_instance list traversal and freeing
- Ensure return_instance is detached from the list before freeing
- Reuse return_instances between multiple uretprobes within task
- Guard against kmemdup() failing in dup_return_instance()
AMD core PMU driver enhancements:
- Relax privilege filter restriction on AMD IBS (Namhyung Kim)
AMD RAPL energy counters support: (Dhananjay Ugwekar)
- Introduce topology_logical_core_id() (K Prateek Nayak)
- Remove the unused get_rapl_pmu_cpumask() function
- Remove the cpu_to_rapl_pmu() function
- Rename rapl_pmu variables
- Make rapl_model struct global
- Add arguments to the init and cleanup functions
- Modify the generic variable names to *_pkg*
- Remove the global variable rapl_msrs
- Move the cntr_mask to rapl_pmus struct
- Add core energy counter support for AMD CPUs
Intel core PMU driver enhancements:
- Support RDPMC 'metrics clear mode' feature (Kan Liang)
- Clarify adaptive PEBS processing (Kan Liang)
- Factor out functions for PEBS records processing (Kan Liang)
- Simplify the PEBS records processing for adaptive PEBS (Kan Liang)
Intel uncore driver enhancements: (Kan Liang)
- Convert buggy pmu->func_id use to pmu->registered
- Support more units on Granite Rapids"
* tag 'perf-core-2025-01-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
perf: map pages in advance
perf/x86/intel/uncore: Support more units on Granite Rapids
perf/x86/intel/uncore: Clean up func_id
perf/x86/intel: Support RDPMC metrics clear mode
uprobes: Guard against kmemdup() failing in dup_return_instance()
perf/x86: Relax privilege filter restriction on AMD IBS
perf/core: Export perf_exclude_event()
uprobes: Reuse return_instances between multiple uretprobes within task
uprobes: Ensure return_instance is detached from the list before freeing
uprobes: Decouple return_instance list traversal and freeing
uprobes: Simplify session consumer tracking
uprobes: add speculative lockless VMA-to-inode-to-uprobe resolution
uprobes: simplify find_active_uprobe_rcu() VMA checks
mm: introduce mmap_lock_speculate_{try_begin|retry}
mm: convert mm_lock_seq to a proper seqcount
mm/gup: Use raw_seqcount_try_begin()
seqlock: add raw_seqcount_try_begin
perf/x86/rapl: Add core energy counter support for AMD CPUs
perf/x86/rapl: Move the cntr_mask to rapl_pmus struct
perf/x86/rapl: Remove the global variable rapl_msrs
...
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Suren Baghdasaryan
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4bbb6df62c |
tools: fix atomic_set() definition to set the value correctly
Currently vma test is failing because of the new vma_assert_attached()
assertion. The check is failing because previous refcount_set() inside
vma_mark_attached() is a NoOp. Fix the definition of atomic_set() to
correctly set the value of the atomic.
Link: https://lkml.kernel.org/r/20241227222220.1726384-1-surenb@google.com
Fixes:
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Suren Baghdasaryan
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eb449bd969 |
mm: convert mm_lock_seq to a proper seqcount
Convert mm_lock_seq to be seqcount_t and change all mmap_write_lock variants to increment it, in-line with the usual seqcount usage pattern. This lets us check whether the mmap_lock is write-locked by checking mm_lock_seq.sequence counter (odd=locked, even=unlocked). This will be used when implementing mmap_lock speculation functions. As a result vm_lock_seq is also change to be unsigned to match the type of mm_lock_seq.sequence. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Link: https://lkml.kernel.org/r/20241122174416.1367052-2-surenb@google.com |
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Lorenzo Stoakes
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c14f8046cd |
tools: testing: add additional vma_internal.h stubs
Patch series "fix error handling in mmap_region() and refactor", v3. The mmap_region() function is somewhat terrifying, with spaghetti-like control flow and numerous means by which issues can arise and incomplete state, memory leaks and other unpleasantness can occur. This series goes to great lengths to simplify how mmap_region() works and to avoid unwinding errors late on in the process of setting up the VMA for the new mapping, and equally avoids such operations occurring while the VMA is in an inconsistent state. This series builds on the previously submitted hotfix patches (see link to v2 below) which addresses the most critical issues around mmap_region(), and further works to improve mmap_region() complexity, stability, and testability. This series moves the code to mm/vma.c to render it userland testable, refactors and simplifies it into smaller functions that are significantly more readable. It additionally avoids performing an attempt at a second merge mid-way through allocating a new VMA, a dubious proposition at best and one that is highly subject to subtle bugs. Rather than do this, we simply note that we ought to retry the merge and do this as a final step. This patch (of 3): Add some additional vma_internal.h stubs in preparation for __mmap_region() being moved to mm/vma.c. Without these the move would result in the tests no longer compiling. Link: https://lkml.kernel.org/r/cover.1729858176.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/74b27e159e261d2ac1fe66a130edad1d61fdc176.1729858176.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jann Horn <jannh@google.com> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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7146de5ff5 |
tools: testing: fix phys_addr_t size on 64-bit systems
The phys_addr_t size is predicated on whether CONFIG_PHYS_ADDR_T_64BIT is
set or not.
In the VMA tests, virt_to_phys() from tools/include/linux casts a volatile
void * pointer to phys_addr_t, if CONFIG_PHYS_ADDR_T_64BIT is not set,
this will be 32-bit and trigger a warning.
Obviously this might also lead to truncation, which we would rather avoid.
Fix this by adjusting the generation of generated/bit-length.h to generate
a CONFIG_PHYS_ADDR_T{bits}BIT define.
This does result in the generation of the useless CONFIG_PHYS_ADDR_T_32BIT
define for 32-bit systems, but this should have no effect, and makes
implementation of this easier.
This resolves the issue and the warning.
[lorenzo.stoakes@oracle.com: VMA tests not properly importing bit-length.h]
Link: https://lkml.kernel.org/r/a6183df9-3108-4d59-8128-4fc6c14e22a5@lucifer.local
Link: https://lkml.kernel.org/r/20241017165638.95602-1-lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Tested-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Lorenzo Stoakes
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e8133a7799 |
tools: testing: add expand-only mode VMA test
Add a test to assert that VMG_FLAG_JUST_EXPAND functions as expected - that is, when the VMA iterator is positioned at the previous VMA and no VMAs proceed it, we observe an expansion with all state as expected. Explicitly place a prior VMA that would otherwise fail this test if the mode were not enabled (as it would traverse to the previous-previous VMA). Link: https://lkml.kernel.org/r/d2f88330254a6448092412bf7dfe077a579ab0dc.1729174352.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jann Horn <jannh@google.com> Cc: kernel test robot <oliver.sang@intel.com> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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01c373e9a5 |
mm: rework vm_ops->close() handling on VMA merge
In commit |
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Lorenzo Stoakes
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cc8cb3697a |
mm: refactor vma_merge() into modify-only vma_merge_existing_range()
The existing vma_merge() function is no longer required to handle what were previously referred to as cases 1-3 (i.e. the merging of a new VMA), as this is now handled by vma_merge_new_vma(). Additionally, simplify the convoluted control flow of the original, maintaining identical logic only expressed more clearly and doing away with a complicated set of cases, rather logically examining each possible outcome - merging of both the previous and subsequent VMA, merging of the previous VMA and merging of the subsequent VMA alone. We now utilise the previously implemented commit_merge() function to share logic with vma_expand() de-duplicating code and providing less surface area for bugs and confusion. In order to do so, we adjust this function to accept parameters specific to merging existing ranges. Link: https://lkml.kernel.org/r/2cf6016b7bfcc4965fc3cde10827560c42e4f12c.1725040657.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Mark Brown <broonie@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Bert Karwatzki <spasswolf@web.de> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kees Cook <kees@kernel.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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cacded5e42 |
mm: avoid using vma_merge() for new VMAs
Abstract vma_merge_new_vma() to use vma_merge_struct and rename the resultant function vma_merge_new_range() to be clear what the purpose of this function is - a new VMA is desired in the specified range, and we wish to see if it is possible to 'merge' surrounding VMAs into this range rather than having to allocate a new VMA. Note that this function uses vma_extend() exclusively, so adopts its requirement that the iterator point at or before the gap. We add an assert to this effect. This is as opposed to vma_merge_existing_range(), which will be introduced in a subsequent commit, and provide the same functionality for cases in which we are modifying an existing VMA. In mmap_region() and do_brk_flags() we open code scenarios where we prefer to use vma_expand() rather than invoke a full vma_merge() operation. Abstract this logic and eliminate all of the open-coding, and also use the same logic for all cases where we add new VMAs to, rather than ultimately use vma_merge(), rather use vma_expand(). Doing so removes duplication and simplifies VMA merging in all such cases, laying the ground for us to eliminate the merging of new VMAs in vma_merge() altogether. Also add the ability for the vmg to track state, and able to report errors, allowing for us to differentiate a failed merge from an inability to allocate memory in callers. This makes it far easier to understand what is happening in these cases avoiding confusion, bugs and allowing for future optimisation. Also introduce vma_iter_next_rewind() to allow for retrieval of the next, and (optionally) the prev VMA, rewinding to the start of the previous gap. Introduce are_anon_vmas_compatible() to abstract individual VMA anon_vma comparison for the case of merging on both sides where the anon_vma of the VMA being merged maybe compatible with prev and next, but prev and next's anon_vma's may not be compatible with each other. Finally also introduce can_vma_merge_left() / can_vma_merge_right() to check adjacent VMA compatibility and that they are indeed adjacent. Link: https://lkml.kernel.org/r/49d37c0769b6b9dc03b27fe4d059173832556392.1725040657.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: Mark Brown <broonie@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Bert Karwatzki <spasswolf@web.de> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kees Cook <kees@kernel.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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fc21959f74 |
mm: abstract vma_expand() to use vma_merge_struct
The purpose of the vmg is to thread merge state through functions and avoid egregious parameter lists. We expand this to vma_expand(), which is used for a number of merge cases. Accordingly, adjust its callers, mmap_region() and relocate_vma_down(), to use a vmg. An added purpose of this change is the ability in a future commit to perform all new VMA range merging using vma_expand(). Link: https://lkml.kernel.org/r/4bc8c9dbc9ca52452ef8e587b28fe555854ceb38.1725040657.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Mark Brown <broonie@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Bert Karwatzki <spasswolf@web.de> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kees Cook <kees@kernel.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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2f1c6611b0 |
mm: introduce vma_merge_struct and abstract vma_merge(),vma_modify()
Rather than passing around huge numbers of parameters to numerous helper
functions, abstract them into a single struct that we thread through the
operation, the vma_merge_struct ('vmg').
Adjust vma_merge() and vma_modify() to accept this parameter, as well as
predicate functions can_vma_merge_before(), can_vma_merge_after(), and the
vma_modify_...() helper functions.
Also introduce VMG_STATE() and VMG_VMA_STATE() helper macros to allow for
easy vmg declaration.
We additionally remove the requirement that vma_merge() is passed a VMA
object representing the candidate new VMA. Previously it used this to
obtain the mm_struct, file and anon_vma properties of the proposed range
(a rather confusing state of affairs), which are now provided by the vmg
directly.
We also remove the pgoff calculation previously performed vma_modify(),
and instead calculate this in VMG_VMA_STATE() via the vma_pgoff_offset()
helper.
Link: https://lkml.kernel.org/r/a955aad09d81329f6fbeb636b2dd10cde7b73dab.1725040657.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Bert Karwatzki <spasswolf@web.de>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Lorenzo Stoakes
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955db39676 |
tools: add VMA merge tests
Add a variety of VMA merge unit tests to assert that the behaviour of VMA merge is correct at an abstract level and VMAs are merged or not merged as expected. These are intentionally added _before_ we start refactoring vma_merge() in order that we can continually assert correctness throughout the rest of the series. In order to reduce churn going forward, we backport the vma_merge_struct data type to the test code which we introduce and use in a future commit, and add wrappers around the merge new and existing VMA cases. Link: https://lkml.kernel.org/r/1c7a0b43cfad2c511a6b1b52f3507696478ff51a.1725040657.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Mark Brown <broonie@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Bert Karwatzki <spasswolf@web.de> Cc: Jeff Xu <jeffxu@chromium.org> Cc: Jiri Olsa <olsajiri@gmail.com> Cc: Kees Cook <kees@kernel.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Paul Moore <paul@paul-moore.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Lorenzo Stoakes
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4e52a60ac5 |
tools: improve vma test Makefile
Patch series "mm: remove vma_merge()", v3. The infamous vma_merge() function has been the cause of a great deal of pain, bugs and confusion for a very long time. It is subtle, contains many corner cases, tries to do far too much and is as a result very fragile. The fact that the function requires there to be a numbering system to cover each possible eventuality with references to each in the many branches of its implementation as to which case you are looking at speaks to all this. Some of this complexity is inherent - unfortunately there is no getting away from the need to figure out precisely how to execute the merge, whether we need to remove VMAs, whether it is safe to do so, what constitutes a mergeable VMA and so on. However, a lot of the complexity is not inherent but instead a product of the function's 'organic' development. Liam has gone to great lengths to improve the situation as a part of his maple tree implementation, greatly improving the readability of the code, and Vlastimil and myself have additionally gone to lengths to try to improve things further. However, with the availability of userland VMA testing, it now becomes possible to perform a rather more significant refactoring while maintaining confidence in its correct operation. An attempt was previously made by Vlastimil [0] to eliminate vma_merge(), however it was rather - brutal - and an astute reader might refer to the date of that patch for insight as to its intent. This series instead divides merge operations into two natural kinds - merges which occur when a NEW vma is being added to the address space, and merges which occur when a vma is being MODIFIED. Happily, the vma_expand() function introduced by Liam, which has the capacity for also deleting a subsequent VMA, covers each of the NEW vma cases. By abstracting the actual final commit of changes to a VMA to its own function, commit_merge() and writing a wrapper around vma_expand() for new VMA cases vma_merge_new_range(), we can avoid having to use vma_merge() for these instances altogether. By doing so we are also able to then de-duplicate all existing merge logic in mmap_region() and do_brk_flags() and have everything invoke this new function, so we universally take the same approach to merging new VMAs. Having done so, we can then completely rework vma_merge() into vma_merge_existing_range() and use this for the instances where a merge is proposed for a region of an existing VMA. This eliminates vma_merge() and its numbered cases and instead divides things into logical cases - merge both, merge left, merge right (the latter 2 being either partial or full merges). The code is heavily annotated with ASCII diagrams and greatly simplified in comparison to the existing vma_merge() function. Having made this change, we take the opportunity to address an issue with merging VMAs possessing a vm_ops->close() hook - commit |
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Lorenzo Stoakes
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9325b8b5a1 |
tools: add skeleton code for userland testing of VMA logic
Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |