| Message ID | 167eb2bd947d9c04b0f6f1a5495ce4a99eeab598.1686210112.git.viresh.kumar@linaro.org |
|---|---|
| State | Accepted |
| Commit | 167eb2bd947d9c04b0f6f1a5495ce4a99eeab598 |
| Headers | show |
| Series | [1/2] OPP: Staticize `lazy_opp_tables` in of.c | expand |
On Thu, Jun 08, 2023 at 01:13:23PM +0530, Viresh Kumar wrote: > The `opp_table_lock` lock is already used to protect the list elsewhere, > use it while adding or removing entries from it. > > Reported-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com> > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > Stephan: Can you please give this a try ? Thanks, works fine for me. (Note that I don't have any races or corruption without this patch either so the testing result might not mean too much.) The patch also looks good! Tested-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com> > > drivers/opp/of.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) > > diff --git a/drivers/opp/of.c b/drivers/opp/of.c > index c740a907ef76..ac2179d5da4c 100644 > --- a/drivers/opp/of.c > +++ b/drivers/opp/of.c > @@ -21,7 +21,7 @@ > > #include "opp.h" > > -/* OPP tables with uninitialized required OPPs */ > +/* OPP tables with uninitialized required OPPs, protected by opp_table_lock */ > static LIST_HEAD(lazy_opp_tables); > > /* > @@ -148,7 +148,10 @@ static void _opp_table_free_required_tables(struct opp_table *opp_table) > > opp_table->required_opp_count = 0; > opp_table->required_opp_tables = NULL; > + > + mutex_lock(&opp_table_lock); > list_del(&opp_table->lazy); > + mutex_unlock(&opp_table_lock); > } > > /* > @@ -197,8 +200,15 @@ static void _opp_table_alloc_required_tables(struct opp_table *opp_table, > } > > /* Let's do the linking later on */ > - if (lazy) > + if (lazy) { > + /* > + * The OPP table is not held while allocating the table, take it > + * now to avoid corruption to the lazy_opp_tables list. > + */ > + mutex_lock(&opp_table_lock); > list_add(&opp_table->lazy, &lazy_opp_tables); > + mutex_unlock(&opp_table_lock); > + } > else > _update_set_required_opps(opp_table); > > -- > 2.31.1.272.g89b43f80a514 >
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index 7046487dc6f4..9f918077cd62 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -29,9 +29,6 @@ */ LIST_HEAD(opp_tables); -/* OPP tables with uninitialized required OPPs */ -LIST_HEAD(lazy_opp_tables); - /* Lock to allow exclusive modification to the device and opp lists */ DEFINE_MUTEX(opp_table_lock); /* Flag indicating that opp_tables list is being updated at the moment */ diff --git a/drivers/opp/of.c b/drivers/opp/of.c index 8246e9b7afe7..c740a907ef76 100644 --- a/drivers/opp/of.c +++ b/drivers/opp/of.c @@ -21,6 +21,9 @@ #include "opp.h" +/* OPP tables with uninitialized required OPPs */ +static LIST_HEAD(lazy_opp_tables); + /* * Returns opp descriptor node for a device node, caller must * do of_node_put(). diff --git a/drivers/opp/opp.h b/drivers/opp/opp.h index 2a057c42ddf4..eb71385d96c1 100644 --- a/drivers/opp/opp.h +++ b/drivers/opp/opp.h @@ -26,7 +26,7 @@ struct regulator; /* Lock to allow exclusive modification to the device and opp lists */ extern struct mutex opp_table_lock; -extern struct list_head opp_tables, lazy_opp_tables; +extern struct list_head opp_tables; /* OPP Config flags */ #define OPP_CONFIG_CLK BIT(0)
`lazy_opp_tables` is only used in of.c, move it there and mark it `static`. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- drivers/opp/core.c | 3 --- drivers/opp/of.c | 3 +++ drivers/opp/opp.h | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-)