| Message ID | 20211016165616.95849-1-xhao@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/damon/core: Optimize kdamod.%d thread creation code | expand |
On 2021/10/17 上午12:56, Xin Hao wrote: > When the ctx->adaptive_targets list is empty, > i did some test on monitor_on interface like this. > > echo on > /sys/kernel/debug/damon/monitor_on > [ 851.988307] damon: kdamond (5390) starts > > Though the ctx->adaptive_targets list is empty, but the > kthread_run still be called, and the kdamond.x thread still > be created, this is meaningless, so t Sorry there made a mistake, i will send a new one. > > So there adds a judgment. only if the ctx->adaptive_targets > list is not empty, and ctx->kdamond pointer is NULL, then call > the __damon_start function. > > Signed-off-by: Xin Hao <xhao@linux.alibaba.com> > --- > mm/damon/core.c | 30 ++++++++++++++++++------------ > 1 file changed, 18 insertions(+), 12 deletions(-) > > diff --git a/mm/damon/core.c b/mm/damon/core.c > index 30e9211f494a..998c707fdca2 100644 > --- a/mm/damon/core.c > +++ b/mm/damon/core.c > @@ -107,6 +107,11 @@ void damon_add_target(struct damon_ctx *ctx, struct damon_target *t) > list_add_tail(&t->list, &ctx->adaptive_targets); > } > > +static int damon_target_empty(struct damon_ctx *ctx) > +{ > + return list_empty(&ctx->adaptive_targets); > +} > + > static void damon_del_target(struct damon_target *t) > { > list_del(&t->list); > @@ -307,15 +312,14 @@ static int __damon_start(struct damon_ctx *ctx) > int err = -EBUSY; > > mutex_lock(&ctx->kdamond_lock); > - if (!ctx->kdamond) { > + ctx->kdamond_stop = false; > + ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", > + nr_running_ctxs); > + if (IS_ERR(ctx->kdamond)) { > + err = PTR_ERR(ctx->kdamond); > + ctx->kdamond = 0; > + } else { > err = 0; > - ctx->kdamond_stop = false; > - ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", > - nr_running_ctxs); > - if (IS_ERR(ctx->kdamond)) { > - err = PTR_ERR(ctx->kdamond); > - ctx->kdamond = 0; > - } > } > mutex_unlock(&ctx->kdamond_lock); > > @@ -347,10 +351,12 @@ int damon_start(struct damon_ctx **ctxs, int nr_ctxs) > } > > for (i = 0; i < nr_ctxs; i++) { > - err = __damon_start(ctxs[i]); > - if (err) > - break; > - nr_running_ctxs++; > + if (!damon_target_empty(ctxs[i]) && !ctxs[i]->kdamond) { > + err = __damon_start(ctxs[i]); > + if (err) > + break; > + nr_running_ctxs++; > + } > } > mutex_unlock(&damon_lock); >
diff --git a/mm/damon/core.c b/mm/damon/core.c index 30e9211f494a..998c707fdca2 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -107,6 +107,11 @@ void damon_add_target(struct damon_ctx *ctx, struct damon_target *t) list_add_tail(&t->list, &ctx->adaptive_targets); } +static int damon_target_empty(struct damon_ctx *ctx) +{ + return list_empty(&ctx->adaptive_targets); +} + static void damon_del_target(struct damon_target *t) { list_del(&t->list); @@ -307,15 +312,14 @@ static int __damon_start(struct damon_ctx *ctx) int err = -EBUSY; mutex_lock(&ctx->kdamond_lock); - if (!ctx->kdamond) { + ctx->kdamond_stop = false; + ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", + nr_running_ctxs); + if (IS_ERR(ctx->kdamond)) { + err = PTR_ERR(ctx->kdamond); + ctx->kdamond = 0; + } else { err = 0; - ctx->kdamond_stop = false; - ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", - nr_running_ctxs); - if (IS_ERR(ctx->kdamond)) { - err = PTR_ERR(ctx->kdamond); - ctx->kdamond = 0; - } } mutex_unlock(&ctx->kdamond_lock); @@ -347,10 +351,12 @@ int damon_start(struct damon_ctx **ctxs, int nr_ctxs) } for (i = 0; i < nr_ctxs; i++) { - err = __damon_start(ctxs[i]); - if (err) - break; - nr_running_ctxs++; + if (!damon_target_empty(ctxs[i]) && !ctxs[i]->kdamond) { + err = __damon_start(ctxs[i]); + if (err) + break; + nr_running_ctxs++; + } } mutex_unlock(&damon_lock);
When the ctx->adaptive_targets list is empty, i did some test on monitor_on interface like this. echo on > /sys/kernel/debug/damon/monitor_on [ 851.988307] damon: kdamond (5390) starts Though the ctx->adaptive_targets list is empty, but the kthread_run still be called, and the kdamond.x thread still be created, this is meaningless, so t So there adds a judgment. only if the ctx->adaptive_targets list is not empty, and ctx->kdamond pointer is NULL, then call the __damon_start function. Signed-off-by: Xin Hao <xhao@linux.alibaba.com> --- mm/damon/core.c | 30 ++++++++++++++++++------------ 1 file changed, 18 insertions(+), 12 deletions(-)