summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorDaniel Jordan <daniel.m.jordan@oracle.com>2020-06-03 15:59:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:09:45 -0700
commit4611ce22468895acd61fee9ac1da810d60617d9a (patch)
treee5f71eeb19df9a835455734e6ec059433bf5854e /include
parentf1b192b117cd418bacf42a9583d7a01855a18fe5 (diff)
padata: allocate work structures for parallel jobs from a pool
padata allocates per-CPU, per-instance work structs for parallel jobs. A do_parallel call assigns a job to a sequence number and hashes the number to a CPU, where the job will eventually run using the corresponding work. This approach fit with how padata used to bind a job to each CPU round-robin, makes less sense after commit bfde23ce200e6 ("padata: unbind parallel jobs from specific CPUs") because a work isn't bound to a particular CPU anymore, and isn't needed at all for multithreaded jobs because they don't have sequence numbers. Replace the per-CPU works with a preallocated pool, which allows sharing them between existing padata users and the upcoming multithreaded user. The pool will also facilitate setting NUMA-aware concurrency limits with later users. The pool is sized according to the number of possible CPUs. With this limit, MAX_OBJ_NUM no longer makes sense, so remove it. If the global pool is exhausted, a parallel job is run in the current task instead to throttle a system trying to do too much in parallel. Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Josh Triplett <josh@joshtriplett.org> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Robert Elliott <elliott@hpe.com> Cc: Shile Zhang <shile.zhang@linux.alibaba.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zi Yan <ziy@nvidia.com> Link: http://lkml.kernel.org/r/20200527173608.2885243-4-daniel.m.jordan@oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r--include/linux/padata.h8
1 files changed, 1 insertions, 7 deletions
diff --git a/include/linux/padata.h b/include/linux/padata.h
index d50bd1a7756f..b4da88f8588c 100644
--- a/include/linux/padata.h
+++ b/include/linux/padata.h
@@ -24,7 +24,6 @@
* @list: List entry, to attach to the padata lists.
* @pd: Pointer to the internal control structure.
* @cb_cpu: Callback cpu for serializatioon.
- * @cpu: Cpu for parallelization.
* @seq_nr: Sequence number of the parallelized data object.
* @info: Used to pass information from the parallel to the serial function.
* @parallel: Parallel execution function.
@@ -34,7 +33,6 @@ struct padata_priv {
struct list_head list;
struct parallel_data *pd;
int cb_cpu;
- int cpu;
unsigned int seq_nr;
int info;
void (*parallel)(struct padata_priv *padata);
@@ -68,15 +66,11 @@ struct padata_serial_queue {
/**
* struct padata_parallel_queue - The percpu padata parallel queue
*
- * @parallel: List to wait for parallelization.
* @reorder: List to wait for reordering after parallel processing.
- * @work: work struct for parallelization.
* @num_obj: Number of objects that are processed by this cpu.
*/
struct padata_parallel_queue {
- struct padata_list parallel;
struct padata_list reorder;
- struct work_struct work;
atomic_t num_obj;
};
@@ -111,7 +105,7 @@ struct parallel_data {
struct padata_parallel_queue __percpu *pqueue;
struct padata_serial_queue __percpu *squeue;
atomic_t refcnt;
- atomic_t seq_nr;
+ unsigned int seq_nr;
unsigned int processed;
int cpu;
struct padata_cpumask cpumask;