user/sven/linux.git/include/linux/stackdepot.h, branch v6.8.6

stackdepot: rename pool_index to pool_index_plus_1

2024-04-10T14:38:14Z

[ Upstream commit a6c1d9cb9a68bfa4512248419c4f4d880d19fe90 ] Commit 3ee34eabac2a ("lib/stackdepot: fix first entry having a 0-handle") changed the meaning of the pool_index field to mean "the pool index plus 1". This made the code accessing this field less self-documenting, as well as causing debuggers such as drgn to not be able to easily remain compatible with both old and new kernels, because they typically do that by testing for presence of the new field. Because stackdepot is a debugging tool, we should make sure that it is debugger friendly. Therefore, give the field a different name to improve readability as well as enabling debugger backwards compatibility. This is needed in 6.9, which would otherwise become an odd release with the new semantics and old name so debuggers wouldn't recognize the new semantics there. Fixes: 3ee34eabac2a ("lib/stackdepot: fix first entry having a 0-handle") Link: https://lkml.kernel.org/r/20240402001500.53533-1-pcc@google.com Link: https://linux-review.googlesource.com/id/Ib3e70c36c1d230dd0a118dc22649b33e768b9f88 Signed-off-by: Peter Collingbourne Acked-by: Vlastimil Babka Reviewed-by: Alexander Potapenko Acked-by: Marco Elver Acked-by: Oscar Salvador Cc: Andrey Konovalov Cc: Michal Hocko Cc: Omar Sandoval Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

lib/stackdepot: move stack_record struct definition into the header

2024-04-10T14:38:14Z

[ Upstream commit 8151c7a35d8bd8a12e93538ef7963ea209b6ab41 ] In order to move the heavy lifting into page_owner code, this one needs to have access to the stack_record structure, which right now sits in lib/stackdepot.c. Move it to the stackdepot.h header so page_owner can access stack_record's struct fields. Link: https://lkml.kernel.org/r/20240215215907.20121-3-osalvador@suse.de Signed-off-by: Oscar Salvador Reviewed-by: Marco Elver Reviewed-by: Vlastimil Babka Acked-by: Andrey Konovalov Cc: Alexander Potapenko Cc: Michal Hocko Signed-off-by: Andrew Morton Stable-dep-of: a6c1d9cb9a68 ("stackdepot: rename pool_index to pool_index_plus_1") Signed-off-by: Sasha Levin

lib/stackdepot: fix comment in include/linux/stackdepot.h

2023-12-29T19:58:42Z

As stack traces can now be evicted from the stack depot, remove the comment saying that they are never removed. Link: https://lkml.kernel.org/r/0ebe712d91f8d302a8947d3c9e9123bc2b1b8440.1703020707.git.andreyknvl@google.com Fixes: 108be8def46e ("lib/stackdepot: allow users to evict stack traces") Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Tetsuo Handa Cc: Vlastimil Babka Signed-off-by: Andrew Morton

lib/stackdepot: allow users to evict stack traces

2023-12-11T00:51:47Z

Add stack_depot_put, a function that decrements the reference counter on a stack record and removes it from the stack depot once the counter reaches 0. Internally, when removing a stack record, the function unlinks it from the hash table bucket and returns to the freelist. With this change, the users of stack depot can call stack_depot_put when keeping a stack trace in the stack depot is not needed anymore. This allows avoiding polluting the stack depot with irrelevant stack traces and thus have more space to store the relevant ones before the stack depot reaches its capacity. Link: https://lkml.kernel.org/r/1d1ad5692ee43d4fc2b3fd9d221331d30b36123f.1700502145.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Marco Elver Cc: Oscar Salvador Cc: Vlastimil Babka Signed-off-by: Andrew Morton

lib/stackdepot: add refcount for records

2023-12-11T00:51:46Z

Add a reference counter for how many times a stack records has been added to stack depot. Add a new STACK_DEPOT_FLAG_GET flag to stack_depot_save_flags that instructs the stack depot to increment the refcount. Do not yet decrement the refcount; this is implemented in one of the following patches. Do not yet enable any users to use the flag to avoid overflowing the refcount. This is preparatory patch for implementing the eviction of stack records from the stack depot. Link: https://lkml.kernel.org/r/a3fc14a2359d019d2a008d4ff8b46a665371ffee.1700502145.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Marco Elver Cc: Oscar Salvador Cc: Vlastimil Babka Signed-off-by: Andrew Morton

lib/stackdepot, kasan: add flags to __stack_depot_save and rename

2023-12-11T00:51:46Z

Change the bool can_alloc argument of __stack_depot_save to a u32 argument that accepts a set of flags. The following patch will add another flag to stack_depot_save_flags besides the existing STACK_DEPOT_FLAG_CAN_ALLOC. Also rename the function to stack_depot_save_flags, as __stack_depot_save is a cryptic name, Link: https://lkml.kernel.org/r/645fa15239621eebbd3a10331e5864b718839512.1700502145.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Marco Elver Cc: Oscar Salvador Cc: Vlastimil Babka Signed-off-by: Andrew Morton

lib/stackdepot: move documentation comments to stackdepot.h

2023-02-17T04:43:52Z

Move all interface- and usage-related documentation comments to include/linux/stackdepot.h. It makes sense to have them in the header where they are available to the interface users. [akpm@linux-foundation.org: grammar fix, per Alexander] Link: https://lkml.kernel.org/r/fbfee41495b306dd8881f9b1c1b80999c885e82f.1676063693.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Signed-off-by: Andrew Morton

lib/stackdepot: various comments clean-ups

2023-02-17T04:43:52Z

Clean up comments in include/linux/stackdepot.h and lib/stackdepot.c: 1. Rework the initialization comment in stackdepot.h. 2. Rework the header comment in stackdepot.c. 3. Various clean-ups for other comments. Also adjust whitespaces for find_stack and depot_alloc_stack call sites. No functional changes. Link: https://lkml.kernel.org/r/5836231b7954355e2311fc9b5870f697ea8e1f7d.1676063693.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Signed-off-by: Andrew Morton

lib/stacktrace, kasan, kmsan: rework extra_bits interface

2023-02-17T04:43:51Z

The current implementation of the extra_bits interface is confusing: passing extra_bits to __stack_depot_save makes it seem that the extra bits are somehow stored in stack depot. In reality, they are only embedded into a stack depot handle and are not used within stack depot. Drop the extra_bits argument from __stack_depot_save and instead provide a new stack_depot_set_extra_bits function (similar to the exsiting stack_depot_get_extra_bits) that saves extra bits into a stack depot handle. Update the callers of __stack_depot_save to use the new interace. This change also fixes a minor issue in the old code: __stack_depot_save does not return NULL if saving stack trace fails and extra_bits is used. Link: https://lkml.kernel.org/r/317123b5c05e2f82854fc55d8b285e0869d3cb77.1676063693.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Signed-off-by: Andrew Morton

lib/stackdepot, mm: rename stack_depot_want_early_init

2023-02-17T04:43:49Z

Rename stack_depot_want_early_init to stack_depot_request_early_init. The old name is confusing, as it hints at returning some kind of intention of stack depot. The new name reflects that this function requests an action from stack depot instead. No functional changes. [akpm@linux-foundation.org: update mm/kmemleak.c] Link: https://lkml.kernel.org/r/359f31bf67429a06e630b4395816a967214ef753.1676063693.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton