[v3,02/36] crypto_pool: Add crypto_pool_reserve_scratch()
Commit Message
Instead of having build-time hardcoded constant, reallocate scratch
area, if needed by user. Different algos, different users may need
different size of temp per-CPU buffer. Only up-sizing supported for
simplicity.
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
crypto/Kconfig | 6 ++++
crypto/crypto_pool.c | 77 ++++++++++++++++++++++++++++++++++---------
include/crypto/pool.h | 3 +-
3 files changed, 69 insertions(+), 17 deletions(-)
Comments
Hi Dmitry,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on 4dc12f37a8e98e1dca5521c14625c869537b50b6]
url: https://github.com/intel-lab-lkp/linux/commits/Dmitry-Safonov/net-tcp-Add-TCP-AO-support/20221028-045452
base: 4dc12f37a8e98e1dca5521c14625c869537b50b6
patch link: https://lore.kernel.org/r/20221027204347.529913-3-dima%40arista.com
patch subject: [PATCH v3 02/36] crypto_pool: Add crypto_pool_reserve_scratch()
config: sparc-allyesconfig
compiler: sparc64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/77f338ef8d76766e86b5b0b722a2a54fd2973c93
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Dmitry-Safonov/net-tcp-Add-TCP-AO-support/20221028-045452
git checkout 77f338ef8d76766e86b5b0b722a2a54fd2973c93
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=sparc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
>> crypto/crypto_pool.c:31: warning: expecting prototype for crypto_pool_reserve_scratch(). Prototype was for FREE_BATCH_SIZE() instead
vim +31 crypto/crypto_pool.c
25
26 /* Slow-path */
27 /**
28 * crypto_pool_reserve_scratch - re-allocates scratch buffer, slow-path
29 * @size: request size for the scratch/temp buffer
30 */
> 31 #define FREE_BATCH_SIZE 64
32 int crypto_pool_reserve_scratch(unsigned long size)
33 {
34 void *free_batch[FREE_BATCH_SIZE];
35 int cpu, err = 0;
36 unsigned int i = 0;
37
38 mutex_lock(&cpool_mutex);
39 if (size == scratch_size) {
40 for_each_possible_cpu(cpu) {
41 if (per_cpu(crypto_pool_scratch, cpu))
42 continue;
43 goto allocate_scratch;
44 }
45 mutex_unlock(&cpool_mutex);
46 return 0;
47 }
48 allocate_scratch:
49 size = max(size, scratch_size);
50 cpus_read_lock();
51 for_each_possible_cpu(cpu) {
52 void *scratch, *old_scratch;
53
54 scratch = kmalloc_node(size, GFP_KERNEL, cpu_to_node(cpu));
55 if (!scratch) {
56 err = -ENOMEM;
57 break;
58 }
59
60 old_scratch = per_cpu(crypto_pool_scratch, cpu);
61 /* Pairs with crypto_pool_get() */
62 WRITE_ONCE(*per_cpu_ptr(&crypto_pool_scratch, cpu), scratch);
63 if (!cpu_online(cpu)) {
64 kfree(old_scratch);
65 continue;
66 }
67 free_batch[i++] = old_scratch;
68 if (i == FREE_BATCH_SIZE) {
69 cpus_read_unlock();
70 synchronize_rcu();
71 while (i > 0)
72 kfree(free_batch[--i]);
73 cpus_read_lock();
74 }
75 }
76 cpus_read_unlock();
77 if (!err)
78 scratch_size = size;
79 mutex_unlock(&cpool_mutex);
80
81 if (i > 0) {
82 synchronize_rcu();
83 while (i > 0)
84 kfree(free_batch[--i]);
85 }
86 return err;
87 }
88 EXPORT_SYMBOL_GPL(crypto_pool_reserve_scratch);
89
@@ -1397,6 +1397,12 @@ config CRYPTO_POOL
help
Per-CPU pool of crypto requests ready for usage in atomic contexts.
+config CRYPTO_POOL_DEFAULT_SCRATCH_SIZE
+ hex "Per-CPU default scratch area size"
+ depends on CRYPTO_POOL
+ default 0x100
+ range 0x100 0x10000
+
if !KMSAN # avoid false positives from assembly
if ARM
source "arch/arm/crypto/Kconfig"
@@ -1,13 +1,14 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include <crypto/pool.h>
+#include <linux/cpu.h>
#include <linux/kref.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/percpu.h>
#include <linux/workqueue.h>
-static unsigned long scratch_size = DEFAULT_CRYPTO_POOL_SCRATCH_SZ;
+static unsigned long scratch_size = CONFIG_CRYPTO_POOL_DEFAULT_SCRATCH_SIZE;
static DEFINE_PER_CPU(void *, crypto_pool_scratch);
struct crypto_pool_entry {
@@ -22,26 +23,69 @@ static struct crypto_pool_entry cpool[CPOOL_SIZE];
static unsigned int cpool_populated;
static DEFINE_MUTEX(cpool_mutex);
-static int crypto_pool_scratch_alloc(void)
+/* Slow-path */
+/**
+ * crypto_pool_reserve_scratch - re-allocates scratch buffer, slow-path
+ * @size: request size for the scratch/temp buffer
+ */
+#define FREE_BATCH_SIZE 64
+int crypto_pool_reserve_scratch(unsigned long size)
{
- int cpu;
-
- lockdep_assert_held(&cpool_mutex);
+ void *free_batch[FREE_BATCH_SIZE];
+ int cpu, err = 0;
+ unsigned int i = 0;
+ mutex_lock(&cpool_mutex);
+ if (size == scratch_size) {
+ for_each_possible_cpu(cpu) {
+ if (per_cpu(crypto_pool_scratch, cpu))
+ continue;
+ goto allocate_scratch;
+ }
+ mutex_unlock(&cpool_mutex);
+ return 0;
+ }
+allocate_scratch:
+ size = max(size, scratch_size);
+ cpus_read_lock();
for_each_possible_cpu(cpu) {
- void *scratch = per_cpu(crypto_pool_scratch, cpu);
+ void *scratch, *old_scratch;
- if (scratch)
+ scratch = kmalloc_node(size, GFP_KERNEL, cpu_to_node(cpu));
+ if (!scratch) {
+ err = -ENOMEM;
+ break;
+ }
+
+ old_scratch = per_cpu(crypto_pool_scratch, cpu);
+ /* Pairs with crypto_pool_get() */
+ WRITE_ONCE(*per_cpu_ptr(&crypto_pool_scratch, cpu), scratch);
+ if (!cpu_online(cpu)) {
+ kfree(old_scratch);
continue;
+ }
+ free_batch[i++] = old_scratch;
+ if (i == FREE_BATCH_SIZE) {
+ cpus_read_unlock();
+ synchronize_rcu();
+ while (i > 0)
+ kfree(free_batch[--i]);
+ cpus_read_lock();
+ }
+ }
+ cpus_read_unlock();
+ if (!err)
+ scratch_size = size;
+ mutex_unlock(&cpool_mutex);
- scratch = kmalloc_node(scratch_size, GFP_KERNEL,
- cpu_to_node(cpu));
- if (!scratch)
- return -ENOMEM;
- per_cpu(crypto_pool_scratch, cpu) = scratch;
+ if (i > 0) {
+ synchronize_rcu();
+ while (i > 0)
+ kfree(free_batch[--i]);
}
- return 0;
+ return err;
}
+EXPORT_SYMBOL_GPL(crypto_pool_reserve_scratch);
static void crypto_pool_scratch_free(void)
{
@@ -138,7 +182,6 @@ int crypto_pool_alloc_ahash(const char *alg)
/* slow-path */
mutex_lock(&cpool_mutex);
-
for (i = 0; i < cpool_populated; i++) {
if (cpool[i].alg && !strcmp(cpool[i].alg, alg)) {
if (kref_read(&cpool[i].kref) > 0) {
@@ -263,7 +306,11 @@ int crypto_pool_get(unsigned int id, struct crypto_pool *c)
return -EINVAL;
}
ret->req = *this_cpu_ptr(cpool[id].req);
- ret->base.scratch = this_cpu_read(crypto_pool_scratch);
+ /*
+ * Pairs with crypto_pool_reserve_scratch(), scartch area is
+ * valid (allocated) until crypto_pool_put().
+ */
+ ret->base.scratch = READ_ONCE(*this_cpu_ptr(&crypto_pool_scratch));
return 0;
}
EXPORT_SYMBOL_GPL(crypto_pool_get);
@@ -4,8 +4,6 @@
#include <crypto/hash.h>
-#define DEFAULT_CRYPTO_POOL_SCRATCH_SZ 128
-
struct crypto_pool {
void *scratch;
};
@@ -20,6 +18,7 @@ struct crypto_pool_ahash {
struct ahash_request *req;
};
+int crypto_pool_reserve_scratch(unsigned long size);
int crypto_pool_alloc_ahash(const char *alg);
void crypto_pool_add(unsigned int id);
void crypto_pool_release(unsigned int id);