| Message ID | 20221013184028.129486-5-leobras@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | CPU isolation improvements | expand |
Friendly ping (for this single patch) On Thu, Oct 13, 2022 at 3:41 PM Leonardo Bras <leobras@redhat.com> wrote: > > Currently pcrypt_aead_init_tfm() will pick callback cpus (ctx->cb_cpu) > from any online cpus. Later padata_reorder() will queue_work_on() the > chosen cb_cpu. > > This is undesired if the chosen cb_cpu is listed as isolated (i.e. using > isolcpus=... or nohz_full=... kernel parameters), since the work queued > will interfere with the workload on the isolated cpu. > > Make sure isolated cpus are not used for pcrypt. > > Signed-off-by: Leonardo Bras <leobras@redhat.com> > --- > crypto/pcrypt.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/crypto/pcrypt.c b/crypto/pcrypt.c > index 9d10b846ccf73..0162629a03957 100644 > --- a/crypto/pcrypt.c > +++ b/crypto/pcrypt.c > @@ -16,6 +16,7 @@ > #include <linux/kobject.h> > #include <linux/cpu.h> > #include <crypto/pcrypt.h> > +#include <linux/sched/isolation.h> > > static struct padata_instance *pencrypt; > static struct padata_instance *pdecrypt; > @@ -175,13 +176,15 @@ static int pcrypt_aead_init_tfm(struct crypto_aead *tfm) > struct pcrypt_instance_ctx *ictx = aead_instance_ctx(inst); > struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm); > struct crypto_aead *cipher; > + const cpumask_t *hk_wq = housekeeping_cpumask(HK_TYPE_WQ); > > cpu_index = (unsigned int)atomic_inc_return(&ictx->tfm_count) % > - cpumask_weight(cpu_online_mask); > + cpumask_weight_and(hk_wq, cpu_online_mask); > > - ctx->cb_cpu = cpumask_first(cpu_online_mask); > + ctx->cb_cpu = cpumask_first_and(hk_wq, cpu_online_mask); > for (cpu = 0; cpu < cpu_index; cpu++) > - ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask); > + ctx->cb_cpu = cpumask_next_and(ctx->cb_cpu, hk_wq, > + cpu_online_mask); > > cipher = crypto_spawn_aead(&ictx->spawn); > > -- > 2.38.0 >
diff --git a/crypto/pcrypt.c b/crypto/pcrypt.c index 9d10b846ccf73..0162629a03957 100644 --- a/crypto/pcrypt.c +++ b/crypto/pcrypt.c @@ -16,6 +16,7 @@ #include <linux/kobject.h> #include <linux/cpu.h> #include <crypto/pcrypt.h> +#include <linux/sched/isolation.h> static struct padata_instance *pencrypt; static struct padata_instance *pdecrypt; @@ -175,13 +176,15 @@ static int pcrypt_aead_init_tfm(struct crypto_aead *tfm) struct pcrypt_instance_ctx *ictx = aead_instance_ctx(inst); struct pcrypt_aead_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_aead *cipher; + const cpumask_t *hk_wq = housekeeping_cpumask(HK_TYPE_WQ); cpu_index = (unsigned int)atomic_inc_return(&ictx->tfm_count) % - cpumask_weight(cpu_online_mask); + cpumask_weight_and(hk_wq, cpu_online_mask); - ctx->cb_cpu = cpumask_first(cpu_online_mask); + ctx->cb_cpu = cpumask_first_and(hk_wq, cpu_online_mask); for (cpu = 0; cpu < cpu_index; cpu++) - ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask); + ctx->cb_cpu = cpumask_next_and(ctx->cb_cpu, hk_wq, + cpu_online_mask); cipher = crypto_spawn_aead(&ictx->spawn);
Currently pcrypt_aead_init_tfm() will pick callback cpus (ctx->cb_cpu) from any online cpus. Later padata_reorder() will queue_work_on() the chosen cb_cpu. This is undesired if the chosen cb_cpu is listed as isolated (i.e. using isolcpus=... or nohz_full=... kernel parameters), since the work queued will interfere with the workload on the isolated cpu. Make sure isolated cpus are not used for pcrypt. Signed-off-by: Leonardo Bras <leobras@redhat.com> --- crypto/pcrypt.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)