From 2c077fdfd09dffb31a890e5095c8ab205138a42e Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Mon, 25 Mar 2024 11:41:59 -0700 Subject: [PATCH] clk: Get runtime PM before walking tree for clk_summary [ Upstream commit 9d1e795f754db1ac3344528b7af0b17b8146f321 ] Similar to the previous commit, we should make sure that all devices are runtime resumed before printing the clk_summary through debugfs. Failure to do so would result in a deadlock if the thread is resuming a device to print clk state and that device is also runtime resuming in another thread, e.g the screen is turning on and the display driver is starting up. We remove the calls to clk_pm_runtime_{get,put}() in this path because they're superfluous now that we know the devices are runtime resumed. This also squashes a bug where the return value of clk_pm_runtime_get() wasn't checked, leading to an RPM count underflow on error paths. Fixes: 1bb294a7981c ("clk: Enable/Disable runtime PM for clk_summary") Cc: Taniya Das Cc: Douglas Anderson Signed-off-by: Stephen Boyd Link: https://lore.kernel.org/r/20240325184204.745706-6-sboyd@kernel.org Reviewed-by: Douglas Anderson Signed-off-by: Sasha Levin --- drivers/clk/clk.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 011e7632541f..4a67c0d4823c 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3321,9 +3321,7 @@ static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c, { struct clk_core *child; - clk_pm_runtime_get(c); clk_summary_show_one(s, c, level); - clk_pm_runtime_put(c); hlist_for_each_entry(child, &c->children, child_node) clk_summary_show_subtree(s, child, level + 1); @@ -3333,11 +3331,15 @@ static int clk_summary_show(struct seq_file *s, void *data) { struct clk_core *c; struct hlist_head **lists = s->private; + int ret; seq_puts(s, " enable prepare protect duty hardware connection\n"); seq_puts(s, " clock count count count rate accuracy phase cycle enable consumer id\n"); seq_puts(s, "---------------------------------------------------------------------------------------------------------------------------------------------\n"); + ret = clk_pm_runtime_get_all(); + if (ret) + return ret; clk_prepare_lock(); @@ -3346,6 +3348,7 @@ static int clk_summary_show(struct seq_file *s, void *data) clk_summary_show_subtree(s, c, 0); clk_prepare_unlock(); + clk_pm_runtime_put_all(); return 0; } @@ -3393,8 +3396,14 @@ static int clk_dump_show(struct seq_file *s, void *data) struct clk_core *c; bool first_node = true; struct hlist_head **lists = s->private; + int ret; + + ret = clk_pm_runtime_get_all(); + if (ret) + return ret; seq_putc(s, '{'); + clk_prepare_lock(); for (; *lists; lists++) { @@ -3407,6 +3416,7 @@ static int clk_dump_show(struct seq_file *s, void *data) } clk_prepare_unlock(); + clk_pm_runtime_put_all(); seq_puts(s, "}\n"); return 0;