| Message ID | 20190418084253.337266121@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | stacktrace: Consolidate stack trace usage | expand |
On Thu, Apr 18, 2019 at 10:41:22AM +0200, Thomas Gleixner wrote: > The struct stack_trace indirection in the stack depot functions is a truly > pointless excercise which requires horrible code at the callsites. > > Provide interfaces based on plain storage arrays. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > Acked-by: Alexander Potapenko <glider@google.com> > --- > include/linux/stackdepot.h | 4 ++ > lib/stackdepot.c | 66 ++++++++++++++++++++++++++++++++------------- > 2 files changed, 51 insertions(+), 19 deletions(-) > > --- a/include/linux/stackdepot.h > +++ b/include/linux/stackdepot.h > @@ -26,7 +26,11 @@ typedef u32 depot_stack_handle_t; > struct stack_trace; > > depot_stack_handle_t depot_save_stack(struct stack_trace *trace, gfp_t flags); > +depot_stack_handle_t stack_depot_save(unsigned long *entries, > + unsigned int nr_entries, gfp_t gfp_flags); > > void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace); > +unsigned int stack_depot_fetch(depot_stack_handle_t handle, > + unsigned long **entries); > > #endif > --- a/lib/stackdepot.c > +++ b/lib/stackdepot.c > @@ -194,40 +194,56 @@ static inline struct stack_record *find_ > return NULL; > } > > -void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) > +/** > + * stack_depot_fetch - Fetch stack entries from a depot > + * Nit: kernel-doc will complain about missing description of @handle. > + * @entries: Pointer to store the entries address > + */ > +unsigned int stack_depot_fetch(depot_stack_handle_t handle, > + unsigned long **entries) > { > union handle_parts parts = { .handle = handle }; > void *slab = stack_slabs[parts.slabindex]; > size_t offset = parts.offset << STACK_ALLOC_ALIGN; > struct stack_record *stack = slab + offset; > > - trace->nr_entries = trace->max_entries = stack->size; > - trace->entries = stack->entries; > - trace->skip = 0; > + *entries = stack->entries; > + return stack->size; > +} > +EXPORT_SYMBOL_GPL(stack_depot_fetch); > + > +void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) > +{ > + unsigned int nent = stack_depot_fetch(handle, &trace->entries); > + > + trace->max_entries = trace->nr_entries = nent; > } > EXPORT_SYMBOL_GPL(depot_fetch_stack); > > /** > - * depot_save_stack - save stack in a stack depot. > - * @trace - the stacktrace to save. > - * @alloc_flags - flags for allocating additional memory if required. > + * stack_depot_save - Save a stack trace from an array > * > - * Returns the handle of the stack struct stored in depot. > + * @entries: Pointer to storage array > + * @nr_entries: Size of the storage array > + * @alloc_flags: Allocation gfp flags > + * > + * Returns the handle of the stack struct stored in depot Can you please s/Returns/Return:/ so that kernel-doc will recognize this as return section. > */ > -depot_stack_handle_t depot_save_stack(struct stack_trace *trace, > - gfp_t alloc_flags) > +depot_stack_handle_t stack_depot_save(unsigned long *entries, > + unsigned int nr_entries, > + gfp_t alloc_flags) > { > - u32 hash; > - depot_stack_handle_t retval = 0; > struct stack_record *found = NULL, **bucket; > - unsigned long flags; > + depot_stack_handle_t retval = 0; > struct page *page = NULL; > void *prealloc = NULL; > + unsigned long flags; > + u32 hash; > > - if (unlikely(trace->nr_entries == 0)) > + if (unlikely(nr_entries == 0)) > goto fast_exit; > > - hash = hash_stack(trace->entries, trace->nr_entries); > + hash = hash_stack(entries, nr_entries); > bucket = &stack_table[hash & STACK_HASH_MASK]; > > /* > @@ -235,8 +251,8 @@ depot_stack_handle_t depot_save_stack(st > * The smp_load_acquire() here pairs with smp_store_release() to > * |bucket| below. > */ > - found = find_stack(smp_load_acquire(bucket), trace->entries, > - trace->nr_entries, hash); > + found = find_stack(smp_load_acquire(bucket), entries, > + nr_entries, hash); > if (found) > goto exit; > > @@ -264,10 +280,10 @@ depot_stack_handle_t depot_save_stack(st > > spin_lock_irqsave(&depot_lock, flags); > > - found = find_stack(*bucket, trace->entries, trace->nr_entries, hash); > + found = find_stack(*bucket, entries, nr_entries, hash); > if (!found) { > struct stack_record *new = > - depot_alloc_stack(trace->entries, trace->nr_entries, > + depot_alloc_stack(entries, nr_entries, > hash, &prealloc, alloc_flags); > if (new) { > new->next = *bucket; > @@ -297,4 +313,16 @@ depot_stack_handle_t depot_save_stack(st > fast_exit: > return retval; > } > +EXPORT_SYMBOL_GPL(stack_depot_save); > + > +/** > + * depot_save_stack - save stack in a stack depot. > + * @trace - the stacktrace to save. > + * @alloc_flags - flags for allocating additional memory if required. > + */ > +depot_stack_handle_t depot_save_stack(struct stack_trace *trace, > + gfp_t alloc_flags) > +{ > + return stack_depot_save(trace->entries, trace->nr_entries, alloc_flags); > +} > EXPORT_SYMBOL_GPL(depot_save_stack); > >
On Thu, 18 Apr 2019, Mike Rapoport wrote: > On Thu, Apr 18, 2019 at 10:41:22AM +0200, Thomas Gleixner wrote: > > > > -void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) > > +/** > > + * stack_depot_fetch - Fetch stack entries from a depot > > + * > > Nit: kernel-doc will complain about missing description of @handle. Duh. > > + * @entries: Pointer to store the entries address > > + */ > > Can you please s/Returns/Return:/ so that kernel-doc will recognize this as > return section. Sure thing. Thanks, tglx
--- a/include/linux/stackdepot.h +++ b/include/linux/stackdepot.h @@ -26,7 +26,11 @@ typedef u32 depot_stack_handle_t; struct stack_trace; depot_stack_handle_t depot_save_stack(struct stack_trace *trace, gfp_t flags); +depot_stack_handle_t stack_depot_save(unsigned long *entries, + unsigned int nr_entries, gfp_t gfp_flags); void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace); +unsigned int stack_depot_fetch(depot_stack_handle_t handle, + unsigned long **entries); #endif --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -194,40 +194,56 @@ static inline struct stack_record *find_ return NULL; } -void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) +/** + * stack_depot_fetch - Fetch stack entries from a depot + * + * @entries: Pointer to store the entries address + */ +unsigned int stack_depot_fetch(depot_stack_handle_t handle, + unsigned long **entries) { union handle_parts parts = { .handle = handle }; void *slab = stack_slabs[parts.slabindex]; size_t offset = parts.offset << STACK_ALLOC_ALIGN; struct stack_record *stack = slab + offset; - trace->nr_entries = trace->max_entries = stack->size; - trace->entries = stack->entries; - trace->skip = 0; + *entries = stack->entries; + return stack->size; +} +EXPORT_SYMBOL_GPL(stack_depot_fetch); + +void depot_fetch_stack(depot_stack_handle_t handle, struct stack_trace *trace) +{ + unsigned int nent = stack_depot_fetch(handle, &trace->entries); + + trace->max_entries = trace->nr_entries = nent; } EXPORT_SYMBOL_GPL(depot_fetch_stack); /** - * depot_save_stack - save stack in a stack depot. - * @trace - the stacktrace to save. - * @alloc_flags - flags for allocating additional memory if required. + * stack_depot_save - Save a stack trace from an array * - * Returns the handle of the stack struct stored in depot. + * @entries: Pointer to storage array + * @nr_entries: Size of the storage array + * @alloc_flags: Allocation gfp flags + * + * Returns the handle of the stack struct stored in depot */ -depot_stack_handle_t depot_save_stack(struct stack_trace *trace, - gfp_t alloc_flags) +depot_stack_handle_t stack_depot_save(unsigned long *entries, + unsigned int nr_entries, + gfp_t alloc_flags) { - u32 hash; - depot_stack_handle_t retval = 0; struct stack_record *found = NULL, **bucket; - unsigned long flags; + depot_stack_handle_t retval = 0; struct page *page = NULL; void *prealloc = NULL; + unsigned long flags; + u32 hash; - if (unlikely(trace->nr_entries == 0)) + if (unlikely(nr_entries == 0)) goto fast_exit; - hash = hash_stack(trace->entries, trace->nr_entries); + hash = hash_stack(entries, nr_entries); bucket = &stack_table[hash & STACK_HASH_MASK]; /* @@ -235,8 +251,8 @@ depot_stack_handle_t depot_save_stack(st * The smp_load_acquire() here pairs with smp_store_release() to * |bucket| below. */ - found = find_stack(smp_load_acquire(bucket), trace->entries, - trace->nr_entries, hash); + found = find_stack(smp_load_acquire(bucket), entries, + nr_entries, hash); if (found) goto exit; @@ -264,10 +280,10 @@ depot_stack_handle_t depot_save_stack(st spin_lock_irqsave(&depot_lock, flags); - found = find_stack(*bucket, trace->entries, trace->nr_entries, hash); + found = find_stack(*bucket, entries, nr_entries, hash); if (!found) { struct stack_record *new = - depot_alloc_stack(trace->entries, trace->nr_entries, + depot_alloc_stack(entries, nr_entries, hash, &prealloc, alloc_flags); if (new) { new->next = *bucket; @@ -297,4 +313,16 @@ depot_stack_handle_t depot_save_stack(st fast_exit: return retval; } +EXPORT_SYMBOL_GPL(stack_depot_save); + +/** + * depot_save_stack - save stack in a stack depot. + * @trace - the stacktrace to save. + * @alloc_flags - flags for allocating additional memory if required. + */ +depot_stack_handle_t depot_save_stack(struct stack_trace *trace, + gfp_t alloc_flags) +{ + return stack_depot_save(trace->entries, trace->nr_entries, alloc_flags); +} EXPORT_SYMBOL_GPL(depot_save_stack);