* [PATCH 0/2] locking/lockdep: A few cleanups @ 2018-12-28 5:01 Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 1/2] locking/lockdep: Simplify mark_held_locks() Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names Frederic Weisbecker 0 siblings, 2 replies; 5+ messages in thread From: Frederic Weisbecker @ 2018-12-28 5:01 UTC (permalink / raw) To: LKML; +Cc: Frederic Weisbecker, Ingo Molnar, Peter Zijlstra Just a few simplification and code cleanup. Frederic Weisbecker (2): locking/lockdep: Simplify mark_held_locks() locking/lockdep: Provide enum lock_usage_bit mask names kernel/locking/lockdep.c | 54 +++++++++++++------------------------- kernel/locking/lockdep_internals.h | 4 +++ 2 files changed, 22 insertions(+), 36 deletions(-) -- 2.7.4 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH 1/2] locking/lockdep: Simplify mark_held_locks() 2018-12-28 5:01 [PATCH 0/2] locking/lockdep: A few cleanups Frederic Weisbecker @ 2018-12-28 5:02 ` Frederic Weisbecker 2019-01-21 11:31 ` [tip:locking/core] " tip-bot for Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names Frederic Weisbecker 1 sibling, 1 reply; 5+ messages in thread From: Frederic Weisbecker @ 2018-12-28 5:02 UTC (permalink / raw) To: LKML; +Cc: Frederic Weisbecker, Ingo Molnar, Peter Zijlstra The enum mark_type appears a bit artificial here. We can directly pass the base enum lock_usage_bit value to mark_held_locks(). All we need then is to add the read index for each lock if necessary. It makes the code clearer. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> --- kernel/locking/lockdep.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 5c837a5..118a554 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2709,35 +2709,28 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, return 1; } -enum mark_type { -#define LOCKDEP_STATE(__STATE) __STATE, -#include "lockdep_states.h" -#undef LOCKDEP_STATE -}; - /* * Mark all held locks with a usage bit: */ static int -mark_held_locks(struct task_struct *curr, enum mark_type mark) +mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit) { - enum lock_usage_bit usage_bit; struct held_lock *hlock; int i; for (i = 0; i < curr->lockdep_depth; i++) { + enum lock_usage_bit hlock_bit = base_bit; hlock = curr->held_locks + i; - usage_bit = 2 + (mark << 2); /* ENABLED */ if (hlock->read) - usage_bit += 1; /* READ */ + hlock_bit += 1; /* READ */ - BUG_ON(usage_bit >= LOCK_USAGE_STATES); + BUG_ON(hlock_bit >= LOCK_USAGE_STATES); if (!hlock->check) continue; - if (!mark_lock(curr, hlock, usage_bit)) + if (!mark_lock(curr, hlock, hlock_bit)) return 0; } @@ -2758,7 +2751,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) * We are going to turn hardirqs on, so set the * usage bit for all held locks: */ - if (!mark_held_locks(curr, HARDIRQ)) + if (!mark_held_locks(curr, LOCK_ENABLED_HARDIRQ)) return; /* * If we have softirqs enabled, then set the usage @@ -2766,7 +2759,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) * this bit from being set before) */ if (curr->softirqs_enabled) - if (!mark_held_locks(curr, SOFTIRQ)) + if (!mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ)) return; curr->hardirq_enable_ip = ip; @@ -2880,7 +2873,7 @@ void trace_softirqs_on(unsigned long ip) * enabled too: */ if (curr->hardirqs_enabled) - mark_held_locks(curr, SOFTIRQ); + mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ); current->lockdep_recursion = 0; } -- 2.7.4 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [tip:locking/core] locking/lockdep: Simplify mark_held_locks() 2018-12-28 5:02 ` [PATCH 1/2] locking/lockdep: Simplify mark_held_locks() Frederic Weisbecker @ 2019-01-21 11:31 ` tip-bot for Frederic Weisbecker 0 siblings, 0 replies; 5+ messages in thread From: tip-bot for Frederic Weisbecker @ 2019-01-21 11:31 UTC (permalink / raw) To: linux-tip-commits Cc: peterz, frederic, akpm, torvalds, hpa, linux-kernel, tglx, will.deacon, mingo, paulmck Commit-ID: 436a49ae7b693161c4fdf98b575ef16243dc2dfa Gitweb: https://git.kernel.org/tip/436a49ae7b693161c4fdf98b575ef16243dc2dfa Author: Frederic Weisbecker <frederic@kernel.org> AuthorDate: Fri, 28 Dec 2018 06:02:00 +0100 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Mon, 21 Jan 2019 11:18:54 +0100 locking/lockdep: Simplify mark_held_locks() The enum mark_type appears a bit artificial here. We can directly pass the base enum lock_usage_bit value to mark_held_locks(). All we need then is to add the read index for each lock if necessary. It makes the code clearer. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/1545973321-24422-2-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/locking/lockdep.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index e805fe3bf87f..1dcd8341e35b 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2709,35 +2709,28 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, return 1; } -enum mark_type { -#define LOCKDEP_STATE(__STATE) __STATE, -#include "lockdep_states.h" -#undef LOCKDEP_STATE -}; - /* * Mark all held locks with a usage bit: */ static int -mark_held_locks(struct task_struct *curr, enum mark_type mark) +mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit) { - enum lock_usage_bit usage_bit; struct held_lock *hlock; int i; for (i = 0; i < curr->lockdep_depth; i++) { + enum lock_usage_bit hlock_bit = base_bit; hlock = curr->held_locks + i; - usage_bit = 2 + (mark << 2); /* ENABLED */ if (hlock->read) - usage_bit += 1; /* READ */ + hlock_bit += 1; /* READ */ - BUG_ON(usage_bit >= LOCK_USAGE_STATES); + BUG_ON(hlock_bit >= LOCK_USAGE_STATES); if (!hlock->check) continue; - if (!mark_lock(curr, hlock, usage_bit)) + if (!mark_lock(curr, hlock, hlock_bit)) return 0; } @@ -2758,7 +2751,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) * We are going to turn hardirqs on, so set the * usage bit for all held locks: */ - if (!mark_held_locks(curr, HARDIRQ)) + if (!mark_held_locks(curr, LOCK_ENABLED_HARDIRQ)) return; /* * If we have softirqs enabled, then set the usage @@ -2766,7 +2759,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip) * this bit from being set before) */ if (curr->softirqs_enabled) - if (!mark_held_locks(curr, SOFTIRQ)) + if (!mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ)) return; curr->hardirq_enable_ip = ip; @@ -2880,7 +2873,7 @@ void trace_softirqs_on(unsigned long ip) * enabled too: */ if (curr->hardirqs_enabled) - mark_held_locks(curr, SOFTIRQ); + mark_held_locks(curr, LOCK_ENABLED_SOFTIRQ); current->lockdep_recursion = 0; } ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names 2018-12-28 5:01 [PATCH 0/2] locking/lockdep: A few cleanups Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 1/2] locking/lockdep: Simplify mark_held_locks() Frederic Weisbecker @ 2018-12-28 5:02 ` Frederic Weisbecker 2019-01-21 11:31 ` [tip:locking/core] " tip-bot for Frederic Weisbecker 1 sibling, 1 reply; 5+ messages in thread From: Frederic Weisbecker @ 2018-12-28 5:02 UTC (permalink / raw) To: LKML; +Cc: Frederic Weisbecker, Ingo Molnar, Peter Zijlstra It makes the code more self-explanatory and tells throughout the code what magic number refers to: * state (Hardirq/Softirq) * direction (used in or enabled above state) * read or write We can even remove some comments that were compensating for the lack of those constant names. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> --- kernel/locking/lockdep.c | 33 +++++++++++---------------------- kernel/locking/lockdep_internals.h | 4 ++++ 2 files changed, 15 insertions(+), 22 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 118a554..115d43e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1624,29 +1624,18 @@ static const char *state_rnames[] = { static inline const char *state_name(enum lock_usage_bit bit) { - return (bit & 1) ? state_rnames[bit >> 2] : state_names[bit >> 2]; + return (bit & LOCK_USAGE_READ_MASK) ? state_rnames[bit >> 2] : state_names[bit >> 2]; } static int exclusive_bit(int new_bit) { - /* - * USED_IN - * USED_IN_READ - * ENABLED - * ENABLED_READ - * - * bit 0 - write/read - * bit 1 - used_in/enabled - * bit 2+ state - */ - - int state = new_bit & ~3; - int dir = new_bit & 2; + int state = new_bit & LOCK_USAGE_STATE_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * keep state, bit flip the direction and strip read. */ - return state | (dir ^ 2); + return state | (dir ^ LOCK_USAGE_DIR_MASK); } static int check_irq_usage(struct task_struct *curr, struct held_lock *prev, @@ -2662,8 +2651,8 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, enum lock_usage_bit new_bit) { int excl_bit = exclusive_bit(new_bit); - int read = new_bit & 1; - int dir = new_bit & 2; + int read = new_bit & LOCK_USAGE_READ_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * mark USED_IN has to look forwards -- to ensure no dependency @@ -2687,19 +2676,19 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, * states. */ if ((!read || !dir || STRICT_READ_CHECKS) && - !usage(curr, this, excl_bit, state_name(new_bit & ~1))) + !usage(curr, this, excl_bit, state_name(new_bit & ~LOCK_USAGE_READ_MASK))) return 0; /* * Check for read in write conflicts */ if (!read) { - if (!valid_state(curr, this, new_bit, excl_bit + 1)) + if (!valid_state(curr, this, new_bit, excl_bit + LOCK_USAGE_READ_MASK)) return 0; if (STRICT_READ_CHECKS && - !usage(curr, this, excl_bit + 1, - state_name(new_bit + 1))) + !usage(curr, this, excl_bit + LOCK_USAGE_READ_MASK, + state_name(new_bit + LOCK_USAGE_READ_MASK))) return 0; } @@ -2723,7 +2712,7 @@ mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit) hlock = curr->held_locks + i; if (hlock->read) - hlock_bit += 1; /* READ */ + hlock_bit += LOCK_USAGE_READ_MASK; BUG_ON(hlock_bit >= LOCK_USAGE_STATES); diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index 88c847a..2ebb9d0 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -22,6 +22,10 @@ enum lock_usage_bit { LOCK_USAGE_STATES }; +#define LOCK_USAGE_READ_MASK 1 +#define LOCK_USAGE_DIR_MASK 2 +#define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK)) + /* * Usage-state bitmasks: */ -- 2.7.4 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* [tip:locking/core] locking/lockdep: Provide enum lock_usage_bit mask names 2018-12-28 5:02 ` [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names Frederic Weisbecker @ 2019-01-21 11:31 ` tip-bot for Frederic Weisbecker 0 siblings, 0 replies; 5+ messages in thread From: tip-bot for Frederic Weisbecker @ 2019-01-21 11:31 UTC (permalink / raw) To: linux-tip-commits Cc: mingo, will.deacon, paulmck, tglx, peterz, torvalds, linux-kernel, hpa, frederic, akpm Commit-ID: bba2a8f1f974a45ca6ceaf688b2be7bc1c418a2f Gitweb: https://git.kernel.org/tip/bba2a8f1f974a45ca6ceaf688b2be7bc1c418a2f Author: Frederic Weisbecker <frederic@kernel.org> AuthorDate: Fri, 28 Dec 2018 06:02:01 +0100 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Mon, 21 Jan 2019 11:18:56 +0100 locking/lockdep: Provide enum lock_usage_bit mask names It makes the code more self-explanatory and tells throughout the code what magic number refers to: - state (Hardirq/Softirq) - direction (used in or enabled above state) - read or write We can even remove some comments that were compensating for the lack of those constant names. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/1545973321-24422-3-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/locking/lockdep.c | 33 +++++++++++---------------------- kernel/locking/lockdep_internals.h | 4 ++++ 2 files changed, 15 insertions(+), 22 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 1dcd8341e35b..608f74ed8bb9 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1624,29 +1624,18 @@ static const char *state_rnames[] = { static inline const char *state_name(enum lock_usage_bit bit) { - return (bit & 1) ? state_rnames[bit >> 2] : state_names[bit >> 2]; + return (bit & LOCK_USAGE_READ_MASK) ? state_rnames[bit >> 2] : state_names[bit >> 2]; } static int exclusive_bit(int new_bit) { - /* - * USED_IN - * USED_IN_READ - * ENABLED - * ENABLED_READ - * - * bit 0 - write/read - * bit 1 - used_in/enabled - * bit 2+ state - */ - - int state = new_bit & ~3; - int dir = new_bit & 2; + int state = new_bit & LOCK_USAGE_STATE_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * keep state, bit flip the direction and strip read. */ - return state | (dir ^ 2); + return state | (dir ^ LOCK_USAGE_DIR_MASK); } static int check_irq_usage(struct task_struct *curr, struct held_lock *prev, @@ -2662,8 +2651,8 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, enum lock_usage_bit new_bit) { int excl_bit = exclusive_bit(new_bit); - int read = new_bit & 1; - int dir = new_bit & 2; + int read = new_bit & LOCK_USAGE_READ_MASK; + int dir = new_bit & LOCK_USAGE_DIR_MASK; /* * mark USED_IN has to look forwards -- to ensure no dependency @@ -2687,19 +2676,19 @@ mark_lock_irq(struct task_struct *curr, struct held_lock *this, * states. */ if ((!read || !dir || STRICT_READ_CHECKS) && - !usage(curr, this, excl_bit, state_name(new_bit & ~1))) + !usage(curr, this, excl_bit, state_name(new_bit & ~LOCK_USAGE_READ_MASK))) return 0; /* * Check for read in write conflicts */ if (!read) { - if (!valid_state(curr, this, new_bit, excl_bit + 1)) + if (!valid_state(curr, this, new_bit, excl_bit + LOCK_USAGE_READ_MASK)) return 0; if (STRICT_READ_CHECKS && - !usage(curr, this, excl_bit + 1, - state_name(new_bit + 1))) + !usage(curr, this, excl_bit + LOCK_USAGE_READ_MASK, + state_name(new_bit + LOCK_USAGE_READ_MASK))) return 0; } @@ -2723,7 +2712,7 @@ mark_held_locks(struct task_struct *curr, enum lock_usage_bit base_bit) hlock = curr->held_locks + i; if (hlock->read) - hlock_bit += 1; /* READ */ + hlock_bit += LOCK_USAGE_READ_MASK; BUG_ON(hlock_bit >= LOCK_USAGE_STATES); diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index 88c847a41c8a..2ebb9d0ea91c 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -22,6 +22,10 @@ enum lock_usage_bit { LOCK_USAGE_STATES }; +#define LOCK_USAGE_READ_MASK 1 +#define LOCK_USAGE_DIR_MASK 2 +#define LOCK_USAGE_STATE_MASK (~(LOCK_USAGE_READ_MASK | LOCK_USAGE_DIR_MASK)) + /* * Usage-state bitmasks: */ ^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-01-21 11:32 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2018-12-28 5:01 [PATCH 0/2] locking/lockdep: A few cleanups Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 1/2] locking/lockdep: Simplify mark_held_locks() Frederic Weisbecker 2019-01-21 11:31 ` [tip:locking/core] " tip-bot for Frederic Weisbecker 2018-12-28 5:02 ` [PATCH 2/2] locking/lockdep: Provide enum lock_usage_bit mask names Frederic Weisbecker 2019-01-21 11:31 ` [tip:locking/core] " tip-bot for Frederic Weisbecker
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