| Message ID | 20240325054403.592298-4-sboyd@kernel.org (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | Fix a deadlock with clk_pm_runtime_get() | expand |
Hik On Sun, Mar 24, 2024 at 10:44 PM Stephen Boyd <sboyd@kernel.org> wrote: > > Initialize this kref once we allocate memory for the struct clk_core so > that we can reuse the release function to free any memory associated > with the structure. This mostly consolidates code, but also clarifies > that the kref lifetime exists once the container structure (struct > clk_core) is allocated instead of leaving it in a half-baked state for > most of __clk_core_init(). > > Cc: Douglas Anderson <dianders@chromium.org> > Signed-off-by: Stephen Boyd <sboyd@kernel.org> > --- > drivers/clk/clk.c | 28 +++++++++++++--------------- > 1 file changed, 13 insertions(+), 15 deletions(-) > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > index 9fc522c26de8..ee80b21f2824 100644 > --- a/drivers/clk/clk.c > +++ b/drivers/clk/clk.c > @@ -3959,8 +3959,6 @@ static int __clk_core_init(struct clk_core *core) > } > > clk_core_reparent_orphans_nolock(); > - > - kref_init(&core->ref); > out: > clk_pm_runtime_put(core); > unlock: > @@ -4189,6 +4187,16 @@ static void clk_core_free_parent_map(struct clk_core *core) > kfree(core->parents); > } > > +/* Free memory allocated for a struct clk_core */ > +static void __clk_release(struct kref *ref) > +{ > + struct clk_core *core = container_of(ref, struct clk_core, ref); > + > + clk_core_free_parent_map(core); > + kfree_const(core->name); > + kfree(core); > +} > + > static struct clk * > __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) > { > @@ -4209,6 +4217,8 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) > goto fail_out; > } > > + kref_init(&core->ref); > + > core->name = kstrdup_const(init->name, GFP_KERNEL); > if (!core->name) { > ret = -ENOMEM; > @@ -4263,12 +4273,10 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) > hw->clk = NULL; > > fail_create_clk: > - clk_core_free_parent_map(core); > fail_parents: > fail_ops: > - kfree_const(core->name); > fail_name: > - kfree(core); > + kref_put(&core->ref, __clk_release); > fail_out: > return ERR_PTR(ret); If it were me, I probably would have: * Removed "fail_out" and turned the one "goto fail_out" to just return the error. * Consolidated the rest of the labels into a single "fail" label. That's definitely just a style opinion though, and IMO the patch is fine as-is and overall cleans up the code. Reviewed-by: Douglas Anderson <dianders@chromium.org>
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 9fc522c26de8..ee80b21f2824 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3959,8 +3959,6 @@ static int __clk_core_init(struct clk_core *core) } clk_core_reparent_orphans_nolock(); - - kref_init(&core->ref); out: clk_pm_runtime_put(core); unlock: @@ -4189,6 +4187,16 @@ static void clk_core_free_parent_map(struct clk_core *core) kfree(core->parents); } +/* Free memory allocated for a struct clk_core */ +static void __clk_release(struct kref *ref) +{ + struct clk_core *core = container_of(ref, struct clk_core, ref); + + clk_core_free_parent_map(core); + kfree_const(core->name); + kfree(core); +} + static struct clk * __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) { @@ -4209,6 +4217,8 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) goto fail_out; } + kref_init(&core->ref); + core->name = kstrdup_const(init->name, GFP_KERNEL); if (!core->name) { ret = -ENOMEM; @@ -4263,12 +4273,10 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw) hw->clk = NULL; fail_create_clk: - clk_core_free_parent_map(core); fail_parents: fail_ops: - kfree_const(core->name); fail_name: - kfree(core); + kref_put(&core->ref, __clk_release); fail_out: return ERR_PTR(ret); } @@ -4348,16 +4356,6 @@ int of_clk_hw_register(struct device_node *node, struct clk_hw *hw) } EXPORT_SYMBOL_GPL(of_clk_hw_register); -/* Free memory allocated for a clock. */ -static void __clk_release(struct kref *ref) -{ - struct clk_core *core = container_of(ref, struct clk_core, ref); - - clk_core_free_parent_map(core); - kfree_const(core->name); - kfree(core); -} - /* * Empty clk_ops for unregistered clocks. These are used temporarily * after clk_unregister() was called on a clock and until last clock
Initialize this kref once we allocate memory for the struct clk_core so that we can reuse the release function to free any memory associated with the structure. This mostly consolidates code, but also clarifies that the kref lifetime exists once the container structure (struct clk_core) is allocated instead of leaving it in a half-baked state for most of __clk_core_init(). Cc: Douglas Anderson <dianders@chromium.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org> --- drivers/clk/clk.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-)