| Message ID | 20240103095006.608744-2-21cnbao@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/zswap & crypto/acompress: remove a couple of memcpy | expand |
On Wed, Jan 3, 2024 at 1:50 AM Barry Song <21cnbao@gmail.com> wrote: > > From: Barry Song <v-songbaohua@oppo.com> > > Almost all CPU-based compressors/decompressors are actually synchronous > though they support acomp APIs. While some hardware has hardware-based > accelerators to offload CPU's work such as hisilicon and intel/qat/, > their drivers are working in async mode. > Letting acomp's users know exactly if the acomp is really async will > help users know if the compression and decompression procedure can > sleep. > > Signed-off-by: Barry Song <v-songbaohua@oppo.com> > Tested-by: Chengming Zhou <zhouchengming@bytedance.com> > --- > crypto/acompress.c | 8 ++++++++ > include/crypto/acompress.h | 9 +++++++++ > 2 files changed, 17 insertions(+) > > diff --git a/crypto/acompress.c b/crypto/acompress.c > index 1c682810a484..99118e879a4a 100644 > --- a/crypto/acompress.c > +++ b/crypto/acompress.c > @@ -152,6 +152,14 @@ struct crypto_acomp *crypto_alloc_acomp_node(const char *alg_name, u32 type, > } > EXPORT_SYMBOL_GPL(crypto_alloc_acomp_node); > > +bool acomp_is_async(struct crypto_acomp *acomp) Is synchronous semantically the same as sleepable? IIUC synchronous code may still sleep, at least generally. The purpose of this change is to know whether we will sleep or not in the zswap code, so I suggest the code should be explicit about sleep-ability instead (e.g. acomp_is_sleepable or acomp_may_sleep).
On Tue, Jan 9, 2024 at 6:36 AM Yosry Ahmed <yosryahmed@google.com> wrote: > > On Wed, Jan 3, 2024 at 1:50 AM Barry Song <21cnbao@gmail.com> wrote: > > > > From: Barry Song <v-songbaohua@oppo.com> > > > > Almost all CPU-based compressors/decompressors are actually synchronous > > though they support acomp APIs. While some hardware has hardware-based > > accelerators to offload CPU's work such as hisilicon and intel/qat/, > > their drivers are working in async mode. > > Letting acomp's users know exactly if the acomp is really async will > > help users know if the compression and decompression procedure can > > sleep. > > > > Signed-off-by: Barry Song <v-songbaohua@oppo.com> > > Tested-by: Chengming Zhou <zhouchengming@bytedance.com> > > --- > > crypto/acompress.c | 8 ++++++++ > > include/crypto/acompress.h | 9 +++++++++ > > 2 files changed, 17 insertions(+) > > > > diff --git a/crypto/acompress.c b/crypto/acompress.c > > index 1c682810a484..99118e879a4a 100644 > > --- a/crypto/acompress.c > > +++ b/crypto/acompress.c > > @@ -152,6 +152,14 @@ struct crypto_acomp *crypto_alloc_acomp_node(const char *alg_name, u32 type, > > } > > EXPORT_SYMBOL_GPL(crypto_alloc_acomp_node); > > > > +bool acomp_is_async(struct crypto_acomp *acomp) > > Is synchronous semantically the same as sleepable? IIUC synchronous > code may still sleep, at least generally. The purpose of this change > is to know whether we will sleep or not in the zswap code, so I > suggest the code should be explicit about sleep-ability instead (e.g. > acomp_is_sleepable or acomp_may_sleep). Thanks, Tosry. sounds reasonable. I'd like to ask for Herbert's comment, do we have a better way to know if an acomp can sleep other than checking the below? return tfm->__crt_alg->cra_type == &crypto_acomp_type; Thanks Barry
diff --git a/crypto/acompress.c b/crypto/acompress.c index 1c682810a484..99118e879a4a 100644 --- a/crypto/acompress.c +++ b/crypto/acompress.c @@ -152,6 +152,14 @@ struct crypto_acomp *crypto_alloc_acomp_node(const char *alg_name, u32 type, } EXPORT_SYMBOL_GPL(crypto_alloc_acomp_node); +bool acomp_is_async(struct crypto_acomp *acomp) +{ + struct crypto_tfm *tfm = crypto_acomp_tfm(acomp); + + return tfm->__crt_alg->cra_type == &crypto_acomp_type; +} +EXPORT_SYMBOL_GPL(acomp_is_async); + struct acomp_req *acomp_request_alloc(struct crypto_acomp *acomp) { struct crypto_tfm *tfm = crypto_acomp_tfm(acomp); diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h index 574cffc90730..d91830c2d442 100644 --- a/include/crypto/acompress.h +++ b/include/crypto/acompress.h @@ -204,6 +204,15 @@ struct acomp_req *acomp_request_alloc(struct crypto_acomp *tfm); */ void acomp_request_free(struct acomp_req *req); +/** + * acomp_is_async() -- check if an acomp is asynchronous(can sleep) + * + * @tfm: ACOMPRESS tfm handle allocated with crypto_alloc_acomp() + * + * Return: true if the acomp is asynchronous, otherwise, false + */ +bool acomp_is_async(struct crypto_acomp *tfm); + /** * acomp_request_set_callback() -- Sets an asynchronous callback *