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2023-12-22entry: Move syscall_enter_from_user_mode() to header fileSven Schnelle1-31/+1
To allow inlining of syscall_enter_from_user_mode(), move it to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-4-svens@linux.ibm.com
2023-12-22entry: Move enter_from_user_mode() to header fileSven Schnelle1-23/+3
To allow inlining of enter_from_user_mode(), move it to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-3-svens@linux.ibm.com
2023-12-22entry: Move exit to usermode functions to header fileSven Schnelle1-43/+9
To allow inlining, move exit_to_user_mode() to entry-common.h. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20231218074520.1998026-2-svens@linux.ibm.com
2023-12-22bpf: Avoid unnecessary use of comma operator in verifierSimon Horman1-1/+1
Although it does not seem to have any untoward side-effects, the use of ';' to separate to assignments seems more appropriate than ','. Flagged by clang-17 -Wcomma No functional change intended. Compile tested only. Signed-off-by: Simon Horman <horms@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Dave Marchevsky <davemarchevsky@fb.com> Link: https://lore.kernel.org/bpf/20231221-bpf-verifier-comma-v1-1-cde2530912e9@kernel.org
2023-12-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netPaolo Abeni13-413/+144
Cross-merge networking fixes after downstream PR. Adjacent changes: drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c 23c93c3b6275 ("bnxt_en: do not map packet buffers twice") 6d1add95536b ("bnxt_en: Modify TX ring indexing logic.") tools/testing/selftests/net/Makefile 2258b666482d ("selftests: add vlan hw filter tests") a0bc96c0cd6e ("selftests: net: verify fq per-band packet limit") Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-12-21Merge tag 'trace-v6.7-rc6-2' of ↵Linus Torvalds2-2/+13
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix another kerneldoc warning - Fix eventfs files to inherit the ownership of its parent directory. The dynamic creation of dentries in eventfs did not take into account if the tracefs file system was mounted with a gid/uid, and would still default to the gid/uid of root. This is a regression. - Fix warning when synthetic event testing is enabled along with startup event tracing testing is enabled * tag 'trace-v6.7-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing / synthetic: Disable events after testing in synth_event_gen_test_init() eventfs: Have event files and directories default to parent uid and gid tracing/synthetic: fix kernel-doc warnings
2023-12-21ring-buffer: Use subbuf_order for buffer page maskingSteven Rostedt (Google)1-8/+11
The comparisons to PAGE_SIZE were all converted to use the buffer->subbuf_order, but the use of PAGE_MASK was missed. Convert all the PAGE_MASK usages over to: (PAGE_SIZE << cpu_buffer->buffer->subbuf_order) - 1 Link: https://lore.kernel.org/linux-trace-kernel/20231219173800.66eefb7a@gandalf.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Fixes: 139f84002145 ("ring-buffer: Page size per ring buffer") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21tracing: Update subbuffer with kilobytes not page orderSteven Rostedt (Google)1-13/+25
Using page order for deciding what the size of the ring buffer sub buffers are is exposing a bit too much of the implementation. Although the sub buffers are only allocated in orders of pages, allow the user to specify the minimum size of each sub-buffer via kilobytes like they can with the buffer size itself. If the user specifies 3 via: echo 3 > buffer_subbuf_size_kb Then the sub-buffer size will round up to 4kb (on a 4kb page size system). If they specify: echo 6 > buffer_subbuf_size_kb The sub-buffer size will become 8kb. and so on. Link: https://lore.kernel.org/linux-trace-kernel/20231219185631.809766769@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21ring-buffer: Just update the subbuffers when changing their allocation orderSteven Rostedt (Google)1-17/+71
The ring_buffer_subbuf_order_set() was creating ring_buffer_per_cpu cpu_buffers with the new subbuffers with the updated order, and if they all successfully were created, then they the ring_buffer's per_cpu buffers would be freed and replaced by them. The problem is that the freed per_cpu buffers contains state that would be lost. Running the following commands: 1. # echo 3 > /sys/kernel/tracing/buffer_subbuf_order 2. # echo 0 > /sys/kernel/tracing/tracing_cpumask 3. # echo 1 > /sys/kernel/tracing/snapshot 4. # echo ff > /sys/kernel/tracing/tracing_cpumask 5. # echo test > /sys/kernel/tracing/trace_marker Would result in: -bash: echo: write error: Bad file descriptor That's because the state of the per_cpu buffers of the snapshot buffer is lost when the order is changed (the order of a freed snapshot buffer goes to 0 to save memory, and when the snapshot buffer is allocated again, it goes back to what the main buffer is). In operation 2, the snapshot buffers were set to "disable" (as all the ring buffers CPUs were disabled). In operation 3, the snapshot is allocated and a call to ring_buffer_subbuf_order_set() replaced the per_cpu buffers losing the "record_disable" count. When it was enabled again, the atomic_dec(&cpu_buffer->record_disable) was decrementing a zero, setting it to -1. Writing 1 into the snapshot would swap the snapshot buffer with the main buffer, so now the main buffer is "disabled", and nothing can write to the ring buffer anymore. Instead of creating new per_cpu buffers and losing the state of the old buffers, basically do what the resize does and just allocate new subbuf pages into the new_pages link list of the per_cpu buffer and if they all succeed, then replace the old sub buffers with the new ones. This keeps the per_cpu buffer descriptor in tact and by doing so, keeps its state. Link: https://lore.kernel.org/linux-trace-kernel/20231219185630.944104939@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Fixes: f9b94daa542a ("ring-buffer: Set new size of the ring buffer sub page") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21ring-buffer: Keep the same size when updating the orderSteven Rostedt (Google)1-1/+4
The function ring_buffer_subbuf_order_set() just updated the sub-buffers to the new size, but this also changes the size of the buffer in doing so. As the size is determined by nr_pages * subbuf_size. If the subbuf_size is increased without decreasing the nr_pages, this causes the total size of the buffer to increase. This broke the latency tracers as the snapshot needs to be the same size as the main buffer. The size of the snapshot buffer is only expanded when needed, and because the order is still the same, the size becomes out of sync with the main buffer, as the main buffer increased in size without the tracing system knowing. Calculate the nr_pages to allocate with the new subbuf_size to be buffer_size / new_subbuf_size. Link: https://lore.kernel.org/linux-trace-kernel/20231219185630.649397785@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Fixes: f9b94daa542a ("ring-buffer: Set new size of the ring buffer sub page") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21tracing: Stop the tracing while changing the ring buffer subbuf sizeSteven Rostedt (Google)1-3/+10
Because the main buffer and the snapshot buffer need to be the same for some tracers, otherwise it will fail and disable all tracing, the tracers need to be stopped while updating the sub buffer sizes so that the tracers see the main and snapshot buffers with the same sub buffer size. Link: https://lore.kernel.org/linux-trace-kernel/20231219185630.353222794@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Fixes: 2808e31ec12e ("ring-buffer: Add interface for configuring trace sub buffer size") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21tracing: Update snapshot order along with main buffer orderSteven Rostedt (Google)1-2/+43
When updating the order of the sub buffers for the main buffer, make sure that if the snapshot buffer exists, that it gets its order updated as well. Link: https://lore.kernel.org/linux-trace-kernel/20231219185630.054668186@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21ring-buffer: Make sure the spare sub buffer used for reads has same sizeSteven Rostedt (Google)1-0/+11
Now that the ring buffer specifies the size of its sub buffers, they all need to be the same size. When doing a read, a swap is done with a spare page. Make sure they are the same size before doing the swap, otherwise the read will fail. Link: https://lore.kernel.org/linux-trace-kernel/20231219185629.763664788@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21ring-buffer: Do no swap cpu buffers if order is differentSteven Rostedt (Google)1-0/+3
As all the subbuffer order (subbuffer sizes) must be the same throughout the ring buffer, check the order of the buffers that are doing a CPU buffer swap in ring_buffer_swap_cpu() to make sure they are the same. If the are not the same, then fail to do the swap, otherwise the ring buffer will think the CPU buffer has a specific subbuffer size when it does not. Link: https://lore.kernel.org/linux-trace-kernel/20231219185629.467894710@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21ring-buffer: Clear pages on error in ring_buffer_subbuf_order_set() failureSteven Rostedt (Google)1-0/+1
On failure to allocate ring buffer pages, the pointer to the CPU buffer pages is freed, but the pages that were allocated previously were not. Make sure they are freed too. Link: https://lore.kernel.org/linux-trace-kernel/20231219185629.179352802@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Fixes: f9b94daa542a ("tracing: Set new size of the ring buffer sub page") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21tracing / synthetic: Disable events after testing in synth_event_gen_test_init()Steven Rostedt (Google)1-0/+11
The synth_event_gen_test module can be built in, if someone wants to run the tests at boot up and not have to load them. The synth_event_gen_test_init() function creates and enables the synthetic events and runs its tests. The synth_event_gen_test_exit() disables the events it created and destroys the events. If the module is builtin, the events are never disabled. The issue is, the events should be disable after the tests are run. This could be an issue if the rest of the boot up tests are enabled, as they expect the events to be in a known state before testing. That known state happens to be disabled. When CONFIG_SYNTH_EVENT_GEN_TEST=y and CONFIG_EVENT_TRACE_STARTUP_TEST=y a warning will trigger: Running tests on trace events: Testing event create_synth_test: Enabled event during self test! ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1 at kernel/trace/trace_events.c:4150 event_trace_self_tests+0x1c2/0x480 Modules linked in: CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.7.0-rc2-test-00031-gb803d7c664d5-dirty #276 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:event_trace_self_tests+0x1c2/0x480 Code: bb e8 a2 ab 5d fc 48 8d 7b 48 e8 f9 3d 99 fc 48 8b 73 48 40 f6 c6 01 0f 84 d6 fe ff ff 48 c7 c7 20 b6 ad bb e8 7f ab 5d fc 90 <0f> 0b 90 48 89 df e8 d3 3d 99 fc 48 8b 1b 4c 39 f3 0f 85 2c ff ff RSP: 0000:ffffc9000001fdc0 EFLAGS: 00010246 RAX: 0000000000000029 RBX: ffff88810399ca80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffffb9f19478 RDI: ffff88823c734e64 RBP: ffff88810399f300 R08: 0000000000000000 R09: fffffbfff79eb32a R10: ffffffffbcf59957 R11: 0000000000000001 R12: ffff888104068090 R13: ffffffffbc89f0a0 R14: ffffffffbc8a0f08 R15: 0000000000000078 FS: 0000000000000000(0000) GS:ffff88823c700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000001f6282001 CR4: 0000000000170ef0 Call Trace: <TASK> ? __warn+0xa5/0x200 ? event_trace_self_tests+0x1c2/0x480 ? report_bug+0x1f6/0x220 ? handle_bug+0x6f/0x90 ? exc_invalid_op+0x17/0x50 ? asm_exc_invalid_op+0x1a/0x20 ? tracer_preempt_on+0x78/0x1c0 ? event_trace_self_tests+0x1c2/0x480 ? __pfx_event_trace_self_tests_init+0x10/0x10 event_trace_self_tests_init+0x27/0xe0 do_one_initcall+0xd6/0x3c0 ? __pfx_do_one_initcall+0x10/0x10 ? kasan_set_track+0x25/0x30 ? rcu_is_watching+0x38/0x60 kernel_init_freeable+0x324/0x450 ? __pfx_kernel_init+0x10/0x10 kernel_init+0x1f/0x1e0 ? _raw_spin_unlock_irq+0x33/0x50 ret_from_fork+0x34/0x60 ? __pfx_kernel_init+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> This is because the synth_event_gen_test_init() left the synthetic events that it created enabled. By having it disable them after testing, the other selftests will run fine. Link: https://lore.kernel.org/linux-trace-kernel/20231220111525.2f0f49b0@gandalf.local.home Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Tom Zanussi <zanussi@kernel.org> Fixes: 9fe41efaca084 ("tracing: Add synth event generation test module") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reported-by: Alexander Graf <graf@amazon.com> Tested-by: Alexander Graf <graf@amazon.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-21bpf: Re-support uid and gid when mounting bpffsDaniel Borkmann1-2/+51
For a clean, conflict-free revert of the token-related patches in commit d17aff807f84 ("Revert BPF token-related functionality"), the bpf fs commit 750e785796bb ("bpf: Support uid and gid when mounting bpffs") was undone temporarily as well. This patch manually re-adds the functionality from the original one back in 750e785796bb, no other functional changes intended. Testing: # mount -t bpf -o uid=65534,gid=65534 bpffs ./foo # ls -la . | grep foo drwxrwxrwt 2 nobody nogroup 0 Dec 20 13:16 foo # mount -t bpf bpffs on /root/foo type bpf (rw,relatime,uid=65534,gid=65534) Also, passing invalid arguments for uid/gid are properly rejected as expected. Fixes: d17aff807f84 ("Revert BPF token-related functionality") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Christian Brauner <brauner@kernel.org> Cc: Jie Jiang <jiejiang@chromium.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/bpf/20231220133805.20953-1-daniel@iogearbox.net
2023-12-21Merge branch 'vfs.file'Christian Brauner2-2/+2
Bring in the changes to the file infrastructure for this cycle. Mostly cleanups and some performance tweaks. * file: remove __receive_fd() * file: stop exposing receive_fd_user() * fs: replace f_rcuhead with f_task_work * file: remove pointless wrapper * file: s/close_fd_get_file()/file_close_fd()/g * Improve __fget_files_rcu() code generation (and thus __fget_light()) * file: massage cleanup of files that failed to open Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-21watch_queue: fix kcalloc() arguments orderDmitry Antipov1-1/+1
When compiling with gcc version 14.0.0 20231220 (experimental) and W=1, I've noticed the following warning: kernel/watch_queue.c: In function 'watch_queue_set_size': kernel/watch_queue.c:273:32: warning: 'kcalloc' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Wcalloc-transposed-args] 273 | pages = kcalloc(sizeof(struct page *), nr_pages, GFP_KERNEL); | ^~~~~~ Since 'n' and 'size' arguments of 'kcalloc()' are multiplied to calculate the final size, their actual order doesn't affect the result and so this is not a bug. But it's still worth to fix it. Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Link: https://lore.kernel.org/r/20231221090139.12579-1-dmantipov@yandex.ru Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-21posix-timers: Get rid of [COMPAT_]SYS_NI() usesLinus Torvalds2-45/+14
Only the posix timer system calls use this (when the posix timer support is disabled, which does not actually happen in any normal case), because they had debug code to print out a warning about missing system calls. Get rid of that special case, and just use the standard COND_SYSCALL interface that creates weak system call stubs that return -ENOSYS for when the system call does not exist. This fixes a kCFI issue with the SYS_NI() hackery: CFI failure at int80_emulation+0x67/0xb0 (target: sys_ni_posix_timers+0x0/0x70; expected type: 0xb02b34d9) WARNING: CPU: 0 PID: 48 at int80_emulation+0x67/0xb0 Reported-by: kernel test robot <oliver.sang@intel.com> Reviewed-by: Sami Tolvanen <samitolvanen@google.com> Tested-by: Sami Tolvanen <samitolvanen@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-12-21wait: Remove uapi header file from main header fileMatthew Wilcox (Oracle)2-1/+4
There's really no overlap between uapi/linux/wait.h and linux/wait.h. There are two files which rely on the uapi file being implcitly included, so explicitly include it there and remove it from the main header file. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Christian Brauner <brauner@kernel.org>
2023-12-21plist: Split out plist_types.hKent Overstreet3-0/+3
Trimming down sched.h dependencies: we don't want to include more than the base types. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-12-21sched.h: move pid helpers to pid.hKent Overstreet2-2/+4
This is needed for killing the sched.h dependency on rcupdate.h, and pid.h is a better place for this code anyways. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-12-21kernel/numa.c: Move logging out of numa.hKent Overstreet2-0/+27
Moving these stub functions to a .c file means we can kill a sched.h dependency on printk.h. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-12-21kernel/fork.c: add missing includeKent Overstreet1-0/+1
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-12-21crash_core: remove duplicated including of kexec.hWang Jinchao1-1/+0
Remove second include of linux/kexec.h Link: https://lkml.kernel.org/r/202312151654+0800-wangjinchao@xfusion.com Signed-off-by: Wang Jinchao <wangjinchao@xfusion.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21kexec: use ALIGN macro instead of open-coding itYuntao Wang1-2/+2
Use ALIGN macro instead of open-coding it to improve code readability. Link: https://lkml.kernel.org/r/20231212142706.25149-1-ytcoode@gmail.com Signed-off-by: Yuntao Wang <ytcoode@gmail.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21fork: remove redundant TASK_UNINTERRUPTIBLEKevin Hao1-1/+1
TASK_KILLABLE already includes TASK_UNINTERRUPTIBLE, so there is no need to add a separate TASK_UNINTERRUPTIBLE. Link: https://lkml.kernel.org/r/20231208084115.1973285-1-haokexin@gmail.com Signed-off-by: Kevin Hao <haokexin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21kexec_file: print out debugging message if requiredBaoquan He2-6/+13
Then when specifying '-d' for kexec_file_load interface, loaded locations of kernel/initrd/cmdline etc can be printed out to help debug. Here replace pr_debug() with the newly added kexec_dprintk() in kexec_file loading related codes. And also print out type/start/head of kimage and flags to help debug. Link: https://lkml.kernel.org/r/20231213055747.61826-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Conor Dooley <conor@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21kexec_file: add kexec_file flag to control debug printingBaoquan He2-0/+5
Patch series "kexec_file: print out debugging message if required", v4. Currently, specifying '-d' on kexec command will print a lot of debugging informationabout kexec/kdump loading with kexec_load interface. However, kexec_file_load prints nothing even though '-d' is specified. It's very inconvenient to debug or analyze the kexec/kdump loading when something wrong happened with kexec/kdump itself or develper want to check the kexec/kdump loading. In this patchset, a kexec_file flag is KEXEC_FILE_DEBUG added and checked in code. If it's passed in, debugging message of kexec_file code will be printed out and can be seen from console and dmesg. Otherwise, the debugging message is printed like beofre when pr_debug() is taken. Note: **** ===== 1) The code in kexec-tools utility also need be changed to support passing KEXEC_FILE_DEBUG to kernel when 'kexec -s -d' is specified. The patch link is here: ========= [PATCH] kexec_file: add kexec_file flag to support debug printing http://lists.infradead.org/pipermail/kexec/2023-November/028505.html 2) s390 also has kexec_file code, while I am not sure what debugging information is necessary. So leave it to s390 developer. Test: **** ==== Testing was done in v1 on x86_64 and arm64. For v4, tested on x86_64 again. And on x86_64, the printed messages look like below: -------------------------------------------------------------- kexec measurement buffer for the loaded kernel at 0x207fffe000. Loaded purgatory at 0x207fff9000 Loaded boot_param, command line and misc at 0x207fff3000 bufsz=0x1180 memsz=0x1180 Loaded 64bit kernel at 0x207c000000 bufsz=0xc88200 memsz=0x3c4a000 Loaded initrd at 0x2079e79000 bufsz=0x2186280 memsz=0x2186280 Final command line is: root=/dev/mapper/fedora_intel--knightslanding--lb--02-root ro rd.lvm.lv=fedora_intel-knightslanding-lb-02/root console=ttyS0,115200N81 crashkernel=256M E820 memmap: 0000000000000000-000000000009a3ff (1) 000000000009a400-000000000009ffff (2) 00000000000e0000-00000000000fffff (2) 0000000000100000-000000006ff83fff (1) 000000006ff84000-000000007ac50fff (2) ...... 000000207fff6150-000000207fff615f (128) 000000207fff6160-000000207fff714f (1) 000000207fff7150-000000207fff715f (128) 000000207fff7160-000000207fff814f (1) 000000207fff8150-000000207fff815f (128) 000000207fff8160-000000207fffffff (1) nr_segments = 5 segment[0]: buf=0x000000004e5ece74 bufsz=0x211 mem=0x207fffe000 memsz=0x1000 segment[1]: buf=0x000000009e871498 bufsz=0x4000 mem=0x207fff9000 memsz=0x5000 segment[2]: buf=0x00000000d879f1fe bufsz=0x1180 mem=0x207fff3000 memsz=0x2000 segment[3]: buf=0x000000001101cd86 bufsz=0xc88200 mem=0x207c000000 memsz=0x3c4a000 segment[4]: buf=0x00000000c6e38ac7 bufsz=0x2186280 mem=0x2079e79000 memsz=0x2187000 kexec_file_load: type:0, start:0x207fff91a0 head:0x109e004002 flags:0x8 --------------------------------------------------------------------------- This patch (of 7): When specifying 'kexec -c -d', kexec_load interface will print loading information, e.g the regions where kernel/initrd/purgatory/cmdline are put, the memmap passed to 2nd kernel taken as system RAM ranges, and printing all contents of struct kexec_segment, etc. These are very helpful for analyzing or positioning what's happening when kexec/kdump itself failed. The debugging printing for kexec_load interface is made in user space utility kexec-tools. Whereas, with kexec_file_load interface, 'kexec -s -d' print nothing. Because kexec_file code is mostly implemented in kernel space, and the debugging printing functionality is missed. It's not convenient when debugging kexec/kdump loading and jumping with kexec_file_load interface. Now add KEXEC_FILE_DEBUG to kexec_file flag to control the debugging message printing. And add global variable kexec_file_dbg_print and macro kexec_dprintk() to facilitate the printing. This is a preparation, later kexec_dprintk() will be used to replace the existing pr_debug(). Once 'kexec -s -d' is specified, it will print out kexec/kdump loading information. If '-d' is not specified, it regresses to pr_debug(). Link: https://lkml.kernel.org/r/20231213055747.61826-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20231213055747.61826-2-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Conor Dooley <conor@kernel.org> Cc: Joe Perches <joe@perches.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21sync mm-stable with mm-hotfixes-stable to pick up depended-upon changesAndrew Morton2-6/+7
2023-12-21kexec: select CRYPTO from KEXEC_FILE instead of depending on itArnd Bergmann1-1/+2
All other users of crypto code use 'select' instead of 'depends on', so do the same thing with KEXEC_FILE for consistency. In practice this makes very little difference as kernels with kexec support are very likely to also include some other feature that already selects both crypto and crypto_sha256, but being consistent here helps for usability as well as to avoid potential circular dependencies. This reverts the dependency back to what it was originally before commit 74ca317c26a3f ("kexec: create a new config option CONFIG_KEXEC_FILE for new syscall"), which changed changed it with the comment "This should be safer as "select" is not recursive", but that appears to have been done in error, as "select" is indeed recursive, and there are no other dependencies that prevent CRYPTO_SHA256 from being selected here. Link: https://lkml.kernel.org/r/20231023110308.1202042-2-arnd@kernel.org Fixes: 74ca317c26a3f ("kexec: create a new config option CONFIG_KEXEC_FILE for new syscall") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Eric DeVolder <eric_devolder@yahoo.com> Tested-by: Eric DeVolder <eric_devolder@yahoo.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Conor Dooley <conor@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21kexec: fix KEXEC_FILE dependenciesArnd Bergmann1-0/+1
The cleanup for the CONFIG_KEXEC Kconfig logic accidentally changed the 'depends on CRYPTO=y' dependency to a plain 'depends on CRYPTO', which causes a link failure when all the crypto support is in a loadable module and kexec_file support is built-in: x86_64-linux-ld: vmlinux.o: in function `__x64_sys_kexec_file_load': (.text+0x32e30a): undefined reference to `crypto_alloc_shash' x86_64-linux-ld: (.text+0x32e58e): undefined reference to `crypto_shash_update' x86_64-linux-ld: (.text+0x32e6ee): undefined reference to `crypto_shash_final' Both s390 and x86 have this problem, while ppc64 and riscv have the correct dependency already. On riscv, the dependency is only used for the purgatory, not for the kexec_file code itself, which may be a bit surprising as it means that with CONFIG_CRYPTO=m, it is possible to enable KEXEC_FILE but then the purgatory code is silently left out. Move this into the common Kconfig.kexec file in a way that is correct everywhere, using the dependency on CRYPTO_SHA256=y only when the purgatory code is available. This requires reversing the dependency between ARCH_SUPPORTS_KEXEC_PURGATORY and KEXEC_FILE, but the effect remains the same, other than making riscv behave like the other ones. On s390, there is an additional dependency on CRYPTO_SHA256_S390, which should technically not be required but gives better performance. Remove this dependency here, noting that it was not present in the initial Kconfig code but was brought in without an explanation in commit 71406883fd357 ("s390/kexec_file: Add kexec_file_load system call"). [arnd@arndb.de: fix riscv build] Link: https://lkml.kernel.org/r/67ddd260-d424-4229-a815-e3fcfb864a77@app.fastmail.com Link: https://lkml.kernel.org/r/20231023110308.1202042-1-arnd@kernel.org Fixes: 6af5138083005 ("x86/kexec: refactor for kernel/Kconfig.kexec") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Eric DeVolder <eric_devolder@yahoo.com> Tested-by: Eric DeVolder <eric_devolder@yahoo.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Conor Dooley <conor@kernel.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-21bpf: Use c->unit_size to select target cache during freeHou Tao1-94/+11
At present, bpf memory allocator uses check_obj_size() to ensure that ksize() of allocated pointer is equal with the unit_size of used bpf_mem_cache. Its purpose is to prevent bpf_mem_free() from selecting a bpf_mem_cache which has different unit_size compared with the bpf_mem_cache used for allocation. But as reported by lkp, the return value of ksize() or kmalloc_size_roundup() may change due to slab merge and it will lead to the warning report in check_obj_size(). The reported warning happened as follows: (1) in bpf_mem_cache_adjust_size(), kmalloc_size_roundup(96) returns the object_size of kmalloc-96 instead of kmalloc-cg-96. The object_size of kmalloc-96 is 96, so size_index for 96 is not adjusted accordingly. (2) the object_size of kmalloc-cg-96 is adjust from 96 to 128 due to slab merge in __kmem_cache_alias(). For SLAB, SLAB_HWCACHE_ALIGN is enabled by default for kmalloc slab, so align is 64 and size is 128 for kmalloc-cg-96. SLUB has a similar merge logic, but its object_size will not be changed, because its align is 8 under x86-64. (3) when unit_alloc() does kmalloc_node(96, __GFP_ACCOUNT, node), ksize() returns 128 instead of 96 for the returned pointer. (4) the warning in check_obj_size() is triggered. Considering the slab merge can happen in anytime (e.g, a slab created in a new module), the following case is also possible: during the initialization of bpf_global_ma, there is no slab merge and ksize() for a 96-bytes object returns 96. But after that a new slab created by a kernel module is merged to kmalloc-cg-96 and the object_size of kmalloc-cg-96 is adjust from 96 to 128 (which is possible for x86-64 + CONFIG_SLAB, because its alignment requirement is 64 for 96-bytes slab). So soon or later, when bpf_global_ma frees a 96-byte-sized pointer which is allocated from bpf_mem_cache with unit_size=96, bpf_mem_free() will free the pointer through a bpf_mem_cache in which unit_size is 128, because the return value of ksize() changes. The warning for the mismatch will be triggered again. A feasible fix is introducing similar APIs compared with ksize() and kmalloc_size_roundup() to return the actually-allocated size instead of size which may change due to slab merge, but it will introduce unnecessary dependency on the implementation details of mm subsystem. As for now the pointer of bpf_mem_cache is saved in the 8-bytes area (or 4-bytes under 32-bit host) above the returned pointer, using unit_size in the saved bpf_mem_cache to select the target cache instead of inferring the size from the pointer itself. Beside no extra dependency on mm subsystem, the performance for bpf_mem_free_rcu() is also improved as shown below. Before applying the patch, the performances of bpf_mem_alloc() and bpf_mem_free_rcu() on 8-CPUs VM with one producer are as follows: kmalloc : alloc 11.69 ± 0.28M/s free 29.58 ± 0.93M/s percpu : alloc 14.11 ± 0.52M/s free 14.29 ± 0.99M/s After apply the patch, the performance for bpf_mem_free_rcu() increases 9% and 146% for kmalloc memory and per-cpu memory respectively: kmalloc: alloc 11.01 ± 0.03M/s free 32.42 ± 0.48M/s percpu: alloc 12.84 ± 0.12M/s free 35.24 ± 0.23M/s After the fixes, there is no need to adjust size_index to fix the mismatch between allocation and free, so remove it as well. Also return NULL instead of ZERO_SIZE_PTR for zero-sized alloc in bpf_mem_alloc(), because there is no bpf_mem_cache pointer saved above ZERO_SIZE_PTR. Fixes: 9077fc228f09 ("bpf: Use kmalloc_size_roundup() to adjust size_index") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/bpf/202310302113.9f8fe705-oliver.sang@intel.com Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231216131052.27621-2-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-12-20PM: hibernate: Repair excess function parameter description warningRandy Dunlap1-1/+0
Function swsusp_close() does not have any parameters, so remove the description of parameter @exclusive to prevent this warning. swap.c:1573: warning: Excess function parameter 'exclusive' description in 'swsusp_close' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-12-20PM: sleep: Remove obsolete comment from unlock_system_sleep()Kevin Hao1-16/+0
With the freezer changes introduced by commit f5d39b020809 ("freezer,sched: Rewrite core freezer logic"), the comment in unlock_system_sleep() has become obsolete, there is no need to retain it. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-12-20tracing/synthetic: fix kernel-doc warningsRandy Dunlap1-2/+2
scripts/kernel-doc warns about using @args: for variadic arguments to functions. Documentation/doc-guide/kernel-doc.rst says that this should be written as @...: instead, so update the source code to match that, preventing the warnings. trace_events_synth.c:1165: warning: Excess function parameter 'args' description in '__synth_event_gen_cmd_start' trace_events_synth.c:1714: warning: Excess function parameter 'args' description in 'synth_event_trace' Link: https://lore.kernel.org/linux-trace-kernel/20231220061226.30962-1-rdunlap@infradead.org Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Fixes: 35ca5207c2d11 ("tracing: Add synthetic event command generation functions") Fixes: 8dcc53ad956d2 ("tracing: Add synth_event_trace() and related functions") Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-12-20timers: Fix nextevt calculation when no timers are pendingAnna-Maria Behnsen1-2/+11
When no timer is queued into an empty timer base, the next_expiry will not be updated. It was originally calculated as base->clk + NEXT_TIMER_MAX_DELTA When the timer base stays empty long enough (> NEXT_TIMER_MAX_DELTA), the next_expiry value of the empty base suggests that there is a timer pending soon. This might be more a kind of a theoretical problem, but the fix doesn't hurt. Use only base->next_expiry value as nextevt when timers are pending. Otherwise nextevt will be jiffies + NEXT_TIMER_MAX_DELTA. As all information is in place, update base->next_expiry value of the empty timer base as well. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-13-anna-maria@linutronix.de
2023-12-20timers: Rework idle logicThomas Gleixner1-20/+20
To improve readability of the code, split base->idle calculation and expires calculation into separate parts. While at it, update the comment about timer base idle marking. Thereby the following subtle change happens if the next event is just one jiffy ahead and the tick was already stopped: Originally base->is_idle remains true in this situation. Now base->is_idle turns to false. This may spare an IPI if a timer is enqueued remotely to an idle CPU that is going to tick on the next jiffy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-12-anna-maria@linutronix.de
2023-12-20timers: Use already existing function for forwarding timer baseAnna-Maria Behnsen1-8/+2
There is an already existing function for forwarding the timer base. Forwarding the timer base is implemented directly in get_next_timer_interrupt() as well. Remove the code duplication and invoke __forward_timer_base() instead. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-11-anna-maria@linutronix.de
2023-12-20timers: Split out forward timer base functionalityAnna-Maria Behnsen1-6/+10
Forwarding timer base is done when the next expiry value is calculated and when a new timer is enqueued. When the next expiry value is calculated the jiffies value is already available and does not need to be reread a second time. Splitting out the forward timer base functionality to make it executable via both contextes - those where jiffies are already known and those, where jiffies need to be read. No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-10-anna-maria@linutronix.de
2023-12-20timers: Clarify check in forward_timer_base()Anna-Maria Behnsen1-4/+7
The current check whether a forward of the timer base is required can be simplified by using an already existing comparison function which is easier to read. The related comment is outdated and was not updated when the check changed in commit 36cd28a4cdd0 ("timers: Lower base clock forwarding threshold"). Use time_before_eq() for the check and replace the comment by copying the comment from the same check inside get_next_timer_interrupt(). Move the precious information of the outdated comment to the proper place in __run_timers(). No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-9-anna-maria@linutronix.de
2023-12-20timers: Move store of next event into __next_timer_interrupt()Anna-Maria Behnsen1-5/+6
Both call sites of __next_timer_interrupt() store the return value directly in base->next_expiry. Move the store into __next_timer_interrupt() and to make its purpose more clear, rename the function to next_expiry_recalc(). No functional change. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-8-anna-maria@linutronix.de
2023-12-20timers: Do not IPI for deferrable timersAnna-Maria Behnsen1-9/+6
Deferrable timers do not prevent CPU from going idle and are not taken into account on idle path. Sending an IPI to a remote CPU when a new first deferrable timer was enqueued will wake up the remote CPU but nothing will be done regarding the deferrable timers. Drop IPI completely when a new first deferrable timer was enqueued. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-7-anna-maria@linutronix.de
2023-12-20tracing/timers: Add tracepoint for tracking timer base is_idle flagAnna-Maria Behnsen1-3/+11
When debugging timer code the timer tracepoints are very important. There is no tracepoint when the is_idle flag of the timer base changes. Instead of always adding manually trace_printk(), add tracepoints which can be easily enabled whenever required. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-6-anna-maria@linutronix.de
2023-12-20tracing/timers: Enhance timer_start tracepointAnna-Maria Behnsen1-1/+1
For starting a timer, the timer is enqueued into a bucket of the timer wheel. The bucket expiry is the defacto expiry of the timer but it is not equal the timer expiry because of increasing granularity when bucket is in a higher level of the wheel. To be able to figure out in a trace whether a timer expired in time or not, the bucket expiry time is required as well. Add bucket expiry time to the timer_start tracepoint and thereby simplify the arguments. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-5-anna-maria@linutronix.de
2023-12-20tick-sched: Warn when next tick seems to be in the pastAnna-Maria Behnsen1-0/+4
When the next tick is in the past, the delta between basemono and the next tick gets negativ. But the next tick should never be in the past. The negative effect of a wrong next tick might be a stop of the tick and timers might expire late. To prevent expensive debugging when changing underlying code, add a WARN_ON_ONCE into this code path. To prevent complete misbehaviour, also reset next_tick to basemono in this case. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-4-anna-maria@linutronix.de
2023-12-20tick/sched: Cleanup confusing variablesAnna-Maria Behnsen1-6/+5
tick_nohz_stop_tick() contains the expires (u64 variable) and tick (ktime_t) variable. In the beginning the value of expires is written to tick. Afterwards none of the variables is changed. They are only used for checks. Drop the not required variable tick and use always expires instead. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-3-anna-maria@linutronix.de
2023-12-20tick-sched: Fix function names in commentsAnna-Maria Behnsen1-5/+5
When referencing functions in comments, it might be helpful to use full function names (including the prefix) to be able to find it when grepping. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/r/20231201092654.34614-2-anna-maria@linutronix.de
2023-12-20ring-buffer: Read and write to ring buffers with custom sub buffer sizeTzvetomir Stoyanov (VMware)3-38/+81
As the size of the ring sub buffer page can be changed dynamically, the logic that reads and writes to the buffer should be fixed to take that into account. Some internal ring buffer APIs are changed: ring_buffer_alloc_read_page() ring_buffer_free_read_page() ring_buffer_read_page() A new API is introduced: ring_buffer_read_page_data() Link: https://lore.kernel.org/linux-trace-devel/20211213094825.61876-6-tz.stoyanov@gmail.com Link: https://lore.kernel.org/linux-trace-kernel/20231219185628.875145995@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> [ Fixed kerneldoc on data_page parameter in ring_buffer_free_read_page() ] Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>