From 40e575b1d0b34b38519d361c10bdf8e0c688957b Mon Sep 17 00:00:00 2001 From: Ohad Ben-Cohen Date: Mon, 2 Jul 2012 20:20:53 +0300 Subject: [PATCH] remoteproc: remove the get_by_name/put API MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove rproc_get_by_name() and rproc_put(), and the associated remoteproc infrastructure that supports it (i.e. klist and friends), because: 1. No one uses them 2. Using them is highly discouraged, and any potential user will be deeply scrutinized and encouraged to move. If a user, that absolutely can't live with the direct boot/shutdown model, does show up one day, then bringing this functionality back is going to be trivial. At this point though, keeping this functionality around is way too much of a maintenance burden. Cc: Sjur Brændeland Cc: Loic Pallardy Cc: Ludovic BARRE Cc: Michal Simek Cc: Fernando Guzman Lugo Cc: Suman Anna Cc: Mark Grosen Acked-by: Stephen Boyd Signed-off-by: Ohad Ben-Cohen --- Documentation/remoteproc.txt | 27 +----- drivers/remoteproc/remoteproc_core.c | 130 --------------------------- include/linux/remoteproc.h | 3 - 3 files changed, 1 insertion(+), 159 deletions(-) diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt index ad6ded4bca5c..f33c3bbbc867 100644 --- a/Documentation/remoteproc.txt +++ b/Documentation/remoteproc.txt @@ -36,8 +36,7 @@ cost. Note: to use this function you should already have a valid rproc handle. There are several ways to achieve that cleanly (devres, pdata, the way remoteproc_rpmsg.c does this, or, if this becomes prevalent, we - might also consider using dev_archdata for this). See also - rproc_get_by_name() below. + might also consider using dev_archdata for this). void rproc_shutdown(struct rproc *rproc) - Power off a remote processor (previously booted with rproc_boot()). @@ -51,30 +50,6 @@ cost. which means that the @rproc handle stays valid even after rproc_shutdown() returns, and users can still use it with a subsequent rproc_boot(), if needed. - - don't call rproc_shutdown() to unroll rproc_get_by_name(), exactly - because rproc_shutdown() _does not_ decrement the refcount of @rproc. - To decrement the refcount of @rproc, use rproc_put() (but _only_ if - you acquired @rproc using rproc_get_by_name()). - - struct rproc *rproc_get_by_name(const char *name) - - Find an rproc handle using the remote processor's name, and then - boot it. If it's already powered on, then just immediately return - (successfully). Returns the rproc handle on success, and NULL on failure. - This function increments the remote processor's refcount, so always - use rproc_put() to decrement it back once rproc isn't needed anymore. - Note: currently rproc_get_by_name() and rproc_put() are not used anymore - by the rpmsg bus and its drivers. We need to scrutinize the use cases - that still need them, and see if we can migrate them to use the non - name-based boot/shutdown interface. - - void rproc_put(struct rproc *rproc) - - Decrement @rproc's power refcount and shut it down if it reaches zero - (essentially by just calling rproc_shutdown), and then decrement @rproc's - validity refcount too. - After this function returns, @rproc may _not_ be used anymore, and its - handle should be considered invalid. - This function should be called _iff_ the @rproc handle was grabbed by - calling rproc_get_by_name(). 3. Typical usage diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index c85db123ba0a..0c77c4fcf436 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -36,7 +36,6 @@ #include #include #include -#include #include #include #include @@ -44,25 +43,6 @@ #include "remoteproc_internal.h" -static void klist_rproc_get(struct klist_node *n); -static void klist_rproc_put(struct klist_node *n); - -/* - * klist of the available remote processors. - * - * We need this in order to support name-based lookups (needed by the - * rproc_get_by_name()). - * - * That said, we don't use rproc_get_by_name() at this point. - * The use cases that do require its existence should be - * scrutinized, and hopefully migrated to rproc_boot() using device-based - * binding. - * - * If/when this materializes, we could drop the klist (and the by_name - * API). - */ -static DEFINE_KLIST(rprocs, klist_rproc_get, klist_rproc_put); - typedef int (*rproc_handle_resources_t)(struct rproc *rproc, struct resource_table *table, int len); typedef int (*rproc_handle_resource_t)(struct rproc *rproc, void *, int avail); @@ -1217,10 +1197,6 @@ EXPORT_SYMBOL(rproc_boot); * which means that the @rproc handle stays valid even after rproc_shutdown() * returns, and users can still use it with a subsequent rproc_boot(), if * needed. - * - don't call rproc_shutdown() to unroll rproc_get_by_name(), exactly - * because rproc_shutdown() _does not_ decrement the refcount of @rproc. - * To decrement the refcount of @rproc, use rproc_put() (but _only_ if - * you acquired @rproc using rproc_get_by_name()). */ void rproc_shutdown(struct rproc *rproc) { @@ -1261,105 +1237,6 @@ out: } EXPORT_SYMBOL(rproc_shutdown); -/* will be called when an rproc is added to the rprocs klist */ -static void klist_rproc_get(struct klist_node *n) -{ - struct rproc *rproc = container_of(n, struct rproc, node); - - get_device(&rproc->dev); -} - -/* will be called when an rproc is removed from the rprocs klist */ -static void klist_rproc_put(struct klist_node *n) -{ - struct rproc *rproc = container_of(n, struct rproc, node); - - put_device(&rproc->dev); -} - -static struct rproc *next_rproc(struct klist_iter *i) -{ - struct klist_node *n; - - n = klist_next(i); - if (!n) - return NULL; - - return container_of(n, struct rproc, node); -} - -/** - * rproc_get_by_name() - find a remote processor by name and boot it - * @name: name of the remote processor - * - * Finds an rproc handle using the remote processor's name, and then - * boot it. If it's already powered on, then just immediately return - * (successfully). - * - * Returns the rproc handle on success, and NULL on failure. - * - * This function increments the remote processor's refcount, so always - * use rproc_put() to decrement it back once rproc isn't needed anymore. - * - * Note: currently this function (and its counterpart rproc_put()) are not - * being used. We need to scrutinize the use cases - * that still need them, and see if we can migrate them to use the non - * name-based boot/shutdown interface. - */ -struct rproc *rproc_get_by_name(const char *name) -{ - struct rproc *rproc; - struct klist_iter i; - int ret; - - /* find the remote processor, and upref its refcount */ - klist_iter_init(&rprocs, &i); - while ((rproc = next_rproc(&i)) != NULL) - if (!strcmp(rproc->name, name)) { - get_device(&rproc->dev); - break; - } - klist_iter_exit(&i); - - /* can't find this rproc ? */ - if (!rproc) { - pr_err("can't find remote processor %s\n", name); - return NULL; - } - - ret = rproc_boot(rproc); - if (ret < 0) { - put_device(&rproc->dev); - return NULL; - } - - return rproc; -} -EXPORT_SYMBOL(rproc_get_by_name); - -/** - * rproc_put() - decrement the refcount of a remote processor, and shut it down - * @rproc: the remote processor - * - * This function tries to shutdown @rproc, and it then decrements its - * refcount. - * - * After this function returns, @rproc may _not_ be used anymore, and its - * handle should be considered invalid. - * - * This function should be called _iff_ the @rproc handle was grabbed by - * calling rproc_get_by_name(). - */ -void rproc_put(struct rproc *rproc) -{ - /* try to power off the remote processor */ - rproc_shutdown(rproc); - - /* downref rproc's refcount */ - put_device(&rproc->dev); -} -EXPORT_SYMBOL(rproc_put); - /** * rproc_register() - register a remote processor * @rproc: the remote processor handle to register @@ -1389,9 +1266,6 @@ int rproc_register(struct rproc *rproc) if (ret < 0) return ret; - /* expose to rproc_get_by_name users */ - klist_add_tail(&rproc->node, &rprocs); - dev_info(dev, "%s is available\n", rproc->name); dev_info(dev, "Note: remoteproc is still under development and considered experimental.\n"); @@ -1417,7 +1291,6 @@ int rproc_register(struct rproc *rproc) if (ret < 0) { dev_err(dev, "request_firmware_nowait failed: %d\n", ret); complete_all(&rproc->firmware_loading_complete); - klist_remove(&rproc->node); } return ret; @@ -1573,9 +1446,6 @@ int rproc_unregister(struct rproc *rproc) list_for_each_entry_safe(rvdev, tmp, &rproc->rvdevs, node) rproc_remove_virtio_dev(rvdev); - /* the rproc is downref'ed as soon as it's removed from the klist */ - klist_del(&rproc->node); - device_del(&rproc->dev); return 0; diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index cbe8a51a21de..b88d6af5ba52 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -449,9 +449,6 @@ struct rproc_vdev { unsigned long gfeatures; }; -struct rproc *rproc_get_by_name(const char *name); -void rproc_put(struct rproc *rproc); - struct rproc *rproc_alloc(struct device *dev, const char *name, const struct rproc_ops *ops, const char *firmware, int len);