git: 3e00f4ab107d - stable/13 - ddb: print the actual syscall name

The branch stable/13 has been updated by mhorne:

URL: https://cgit.FreeBSD.org/src/commit/?id=3e00f4ab107d68d5f7782c8bdeeead41cb06b38b

commit 3e00f4ab107d68d5f7782c8bdeeead41cb06b38b
Author:     Mitchell Horne <mhorne@FreeBSD.org>
AuthorDate: 2022-10-28 21:20:05 +0000
Commit:     Mitchell Horne <mhorne@FreeBSD.org>
CommitDate: 2022-11-06 14:54:46 +0000

    ddb: print the actual syscall name
    
    Some architectures will pretty-print a system call trap in the
    backtrace. Rather than printing the symbol, use the syscallname()
    function to pull the string from the sv_syscallnames array corresponding
    to the process. This simplifies the function somewhat.
    
    Mostly, this will result in dropping the "sys" prefix, e.g. "sys_exit"
    will now be printed simply as "exit".
    
    Make two minor tweaks to the function signature: use a u_int for the
    syscall number since this is a more correct type (see the 'code' member
    of struct syscall_args), and make the thread pointer the first argument.
    The latter is more natural and conventional.
    
    Suggested by:   jrtc27
    Reviewed by:    jrtc27, markj, jhb
    MFC after:      1 week
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D37200
    
    (cherry picked from commit aba921bd9e1869dae9ae4cc6e0c048f997401034)
---
 sys/amd64/amd64/db_trace.c |  2 +-
 sys/ddb/db_sym.c           | 18 +++++-------------
 sys/ddb/db_sym.h           |  2 +-
 sys/i386/i386/db_trace.c   |  2 +-
 sys/riscv/riscv/db_trace.c |  2 +-
 5 files changed, 9 insertions(+), 17 deletions(-)

diff --git a/sys/amd64/amd64/db_trace.c b/sys/amd64/amd64/db_trace.c
index 1eae53f3d06d..ebda172994be 100644
--- a/sys/amd64/amd64/db_trace.c
+++ b/sys/amd64/amd64/db_trace.c
@@ -218,7 +218,7 @@ db_nextframe(struct amd64_frame **fp, db_addr_t *ip, struct thread *td)
 			break;
 		case SYSCALL:
 			db_printf("--- syscall");
-			db_decode_syscall(tf->tf_rax, td);
+			db_decode_syscall(td, tf->tf_rax);
 			break;
 		case INTERRUPT:
 			db_printf("--- interrupt");
diff --git a/sys/ddb/db_sym.c b/sys/ddb/db_sym.c
index 43a0b5447479..19aba9f7abb2 100644
--- a/sys/ddb/db_sym.c
+++ b/sys/ddb/db_sym.c
@@ -485,23 +485,15 @@ db_sym_numargs(c_db_sym_t sym, int *nargp, char **argnames)
 }
 
 void
-db_decode_syscall(int number, struct thread *td)
+db_decode_syscall(struct thread *td, u_int number)
 {
 	struct proc *p;
-	c_db_sym_t sym;
-	db_expr_t diff;
-	sy_call_t *f;
-	const char *symname;
 
-	db_printf(" (%d", number);
+	db_printf(" (%u", number);
 	p = (td != NULL) ? td->td_proc : NULL;
-	if (p != NULL && 0 <= number && number < p->p_sysent->sv_size) {
-		f = p->p_sysent->sv_table[number].sy_call;
-		sym = db_search_symbol((db_addr_t)f, DB_STGY_ANY, &diff);
-		if (sym != DB_SYM_NULL && diff == 0) {
-			db_symbol_values(sym, &symname, NULL);
-			db_printf(", %s, %s", p->p_sysent->sv_name, symname);
-		}
+	if (p != NULL) {
+		db_printf(", %s, %s", p->p_sysent->sv_name,
+		    syscallname(p, number));
 	}
 	db_printf(")");
 }
diff --git a/sys/ddb/db_sym.h b/sys/ddb/db_sym.h
index 7ad7fb71f970..76dd0a5837de 100644
--- a/sys/ddb/db_sym.h
+++ b/sys/ddb/db_sym.h
@@ -105,6 +105,6 @@ bool		X_db_sym_numargs(db_symtab_t *, c_db_sym_t, int *, char **);
 void		X_db_symbol_values(db_symtab_t *symtab, c_db_sym_t sym,
 		    const char **namep, db_expr_t *valuep);
 
-void		db_decode_syscall(int number, struct thread *td);
+void		db_decode_syscall(struct thread *td, u_int number);
 
 #endif /* !_DDB_DB_SYM_H_ */
diff --git a/sys/i386/i386/db_trace.c b/sys/i386/i386/db_trace.c
index aee90ee058de..47057906fa58 100644
--- a/sys/i386/i386/db_trace.c
+++ b/sys/i386/i386/db_trace.c
@@ -372,7 +372,7 @@ db_nextframe(struct i386_frame **fp, db_addr_t *ip, struct thread *td)
 		break;
 	case SYSCALL:
 		db_printf("--- syscall");
-		db_decode_syscall(tf->tf_eax, td);
+		db_decode_syscall(td, tf->tf_eax);
 		break;
 	case INTERRUPT:
 		db_printf("--- interrupt");
diff --git a/sys/riscv/riscv/db_trace.c b/sys/riscv/riscv/db_trace.c
index ef8698917021..295d8631ab2e 100644
--- a/sys/riscv/riscv/db_trace.c
+++ b/sys/riscv/riscv/db_trace.c
@@ -97,7 +97,7 @@ db_stack_trace_cmd(struct thread *td, struct unwind_state *frame)
 				    tf->tf_scause & SCAUSE_CODE);
 			} else if (tf->tf_scause == SCAUSE_ECALL_USER) {
 				db_printf("--- syscall");
-				db_decode_syscall(td->td_sa.code, td);
+				db_decode_syscall(td, td->td_sa.code);
 				db_printf("\n");
 			} else {
 				db_printf("--- exception %ld, tval = %#lx\n",